World Surface Coatings Abstracts (WSCA) - Highlights 2005

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WSCA Highlights of the Month - December 2005

The December 2005 issue of WSCA contains abstracts of 753 articles including the following examples:

Section 02 Patents: Pigments, Extenders, Dyestuffs and Phosphors

ROHM & HAAS CO Nanocomposite compositions and methods for making and using same. United States Patent 6914095: Off. Gaz. 2005, Vol 1296 No 1.
A process is disclosed for preparing an aqueous nanocomposite dispersion. The process involves providing at least one first ethylenically-unsatd. monomer, providing an aqueous clay dispersion comprising an at least partially exfoliated clay and, optionally, at least one second ethylenically-unsatd. monomer, wherein the clay has a first exchangeable cation, adding a multivalent second cation to the aqueous clay dispersion, wherein at least a portion of the second cation exchanges with at least a portion of the first cation to form a modified aqueous clay dispersion, combining the first ethylenically-unsatd. monomer and the modified aqueous clay dispersion, and polymerising at least a portion of the first or second monomer to form the aqueous nanocomposite dispersion. At least one of the first or the second ethylenically-unsatd. monomer comprises a polar monomer. (WSCA Item Number 05/07704)

Section 31 Paints, Varnishes and Lacquers (General)

DE JOUSSINEAU G, PETIT J-P & BARQUINS M Simulation of the flaking paint due to internal stresses: a simple model. Internat. J. Adhes. Adhesives 2005, Vol 25 No 6, 518-26.
A simple theoretical and experimental model is presented to explain the flaking off of paints, from a pre-existing defect, due to the influence of internal stresses provoked by the variation of ambient temperature and a long or strong illumination. The experimental model is constructed of two superimposed rubber strips, one of them being submitted to an instantaneous elongation or to a constant speed of strain. The detachment of the other strip, that represents the peeling and the flaking off of the paint layer, is measured and analysed using concepts of fracture mechanics, such as the strain energy release rate, in order to determine the conditions of stability and propagation of a crack at the interface, and to draw a master curve representing the dissipation function as a function of the crack propagation speed. 10 refs. (WSCA Item Number 05/07873)

Section 53 Weathering, Corrosion, Etc

HENDERSON K, HUNT R W G, SPITLER K & BOISSEAU J Etch damage to motor vehicle coatings. JCT CoatingsTech 2005, Vol 2 No 18, 38-43.
The complex problem of the influence of exposure conditions on paint damage due to etch was investigated. Statistical evidence was obtained that the general assumption that acid moisture evaporates on the surface, concentrating acidity, thereby decomposing the coating and leaving a non-reversible ring, or water spot, is valid. It appears that evaporating dew is a much more significant contributor to etching than rain, and there is also some evidence that thermal shocks of 10 deg. C in a 15-20 minute interval may also contribute to etching, and also that rain may even mitigate the etching problem by washing the residue from the surface. The year was regarded by the industry as a severe season. (WSCA Item Number 05/08033)

Section 67 Mechanical and Rheological Properties

MAHLI D M, WEGNER J M, GLASS J E & PHILLIPS D G Water-borne latex coatings of colour. I. Component influences on viscosity decreases. JCT Research 2005, Vol 2 No 8, 627-34.
The influence of surfactants on viscosity variations in water-borne latex coatings was examined. Aqueous solutions containing large quantities of five different surfactants, and the smallest particle size of the colourants, carbon black, were prepared. Large quantities of surfactant were used to allow for adsorption on, and stabilisation of carbon black. When traditional associative polymers were used to thicken carbon black dispersions, viscosity decreases were not observed, for most of the surfactant is adsorbed on the carbon black's surface. There was enough surfactant, however, to promote viscosity decrease in the case of comb hydrophobically-modified urethane thickened carbon black dispersion. The effect was also examined of addition of surfactant compositions containing carbon black to pastel water-borne coatings containing vinyl acrylic latex, titanium dioxide, etc. Pastel paints containing carbon black, a yellow azo pigment and a red azo pigment were also compared. 23 refs. (WSCA Item Number 05/08180)

Section 71 Other Properties and Testing Methods

NOSAKA A Y & NOSAKA Y Characteristics of water absorbed on titanium dioxide photocatalytic surfaces as studied by proton nuclear magnetic resonance spectroscopy. Bull. Chem. Soc. Japan 2005, Vol 78 No 9, 1595-607.
A review is presented of research on the characteristics of adsorbed water molecules and the photocatalytic reaction sites of incorporated organic molecules on various titanium dioxide photocatalysts in powder and film forms by means of proton NMR. It is noted that the absorbed water may be categorised into four distinctively different water species, i.e, rigid water species with restricted mobility near the solid surface, less mobile water molecules in the intermediate water layer, relatively mobile water molecules in the outer water layer and loosely absorbed water molecules which exchange slowly with gaseous water molecules in air. The temperature dependence of the NMR signal to a small quantity of ethanol molecules incorporated in titanium dioxide suggests that the actual photocatalytic reaction site may be these adsorbed water regions. The surface conversion of hydrophilic properties of titanium dioxide films induced by photoirradiation is well reflected in the NMR signal change. The enhancement of water molecularly adsorbed on titanium dioxide films is evidently detected on ultraviolet irradiation; this phenomenon has been difficult to elucidate so far with alternative spectroscopic techniques. 99 refs. (WSCA Item Number 05/08259)

Reviews of the following books also appeared in the December 2005 issue of WSCA: the full book reviews can be read on the Library Catalogue page of the PRA web site.

Section Books

HEILEN W Silicone Resins and their Combinations. Vincentz Network, Hannover 2005, 101 pp. (ISBN 3-87870-794-0). Price 99 euros. (WSCA Item Number 05/08400)

MARTIN J W, RYNTZ R A & DICKIE R A (EDITORS) Service Life Prediction: Challenging the Status Quo. Federation of Societies for Coatings Technology, Blue Bell (Pennsylvania) 2005, 431 pp. (ISBN 0-934010-60-9). Price $195 (FSCT members $150). (WSCA Item Number 05/08401)

For further information on WSCA please contact the Editor: Dr Norman Morgan

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WSCA Highlights of the Month - November 2005

The November 2005 issue of WSCA contains abstracts of 730 articles including the following examples:

Section 03 Oils, Waxes and Related Materials

QUINTERO C, MENDON S K, SMITH O W & THAMES S F: Miniemulsion polymerisation of vegetable oil macromonomers. (Proc. 32nd Internat. Waterborne, High-Solids & Powder Coatings Symposium, New Orleans 2005, Paper, 43-53.)
A soyabean oil-based vegetable oil macromonomer (VOMM) was used as a copolymerisable hydrophobe in miniemulsion polymerisation. Monomer droplets were stabilised prior to polymerisation via catastrophic phase inversion to form stable and small droplets (100 nm). Dynamic light scattering analysis was used to confirm miniemulsion stability. A coagulum-free latex was obtained after polymerisation. Surface tension measurements and light scattering techniques were used to confirm that monomer droplet nucleation was the dominant mechanism. Gel content testing indicated the formation of a highly branched or cross-linked network upon film application. The miniemulsion technique permitted vegetable oil macromonomer incorporation as high as 35 wt. % into the polymer backbone. 26 refs. (WSCA Item Number 05/06950)

Section 53 Weathering, Corrosion, Etc

CHALLENER C: Government coatings research: fundamental to performance. (JCT CoatingsTech 2005, Vol 2 No 17, 32-6.)
Coatings research activities within the United States Department of Defence and NASA are discussed; they address critical issues facing the military and upcoming space exploration initiatives. Corrosion detection and control, environmentally friendly/compliant technologies, and rapid cure topcoats lie at the centre of many projects within the Army, Navy, Air Force and NASA coating research laboratories. Emphasis is given to the study of corrosion-resistant coatings. Corrosion has been identified as one of the largest components of life-cycle costs for weapon systems and a major cause of downtime for critical military assets. Chemical agent-resistant coatings are being developed by the Army. The Navy is considered to have the challenge of maintaining functional antifouling coatings, which have recently come under scrutiny by global regulatory agencies. The Navy is investigating biocides and other technologies as alternatives to their currently used copper-based antifoulants in order to be prepared for any further changes in regulations. Environmental concerns and the need to obtain low volatile organic compound (VOC) levels are a centre of much of the research in military coatings. (WSCA Item Number 05/07253)

PHALKE A V & GANGOTRI L T: Powder coatings based on bitumen and rosin. (Paintindia 2005, Vol 55 No 5, 63 (4 pp).)
Thermoplastic powder coatings based on bitumen and rosin were prepared by choosing six different combinations. The blends were found to provide good film properties such as adhesion, scratch hardness, water and salt water resistance, and resistance to humidity. These thermoplastic powder coatings did not require the application of any primer on metal surfaces. The 60:40 (bitumen/rosin) blend was found to provide maximum scratch hardness. The stoving temperature of the coating was kept at 130 deg. C for 30 minutes. The coatings were black in colour, smooth and semi-glossy. 13 refs. (WSCA Item Number 05/07275)

Section 55 Fouling and Microbiological Attack

YEBRA D M, KIIL S, DAM-JOHANSEN K & WEINELL C: Reaction rate estimation of controlled-release antifouling paint binders: rosin-based systems. (Progr. Org. Coat. 2005, Vol 53 No 4, 256-75.)
The reaction mechanisms and the rate of reaction with sea water were investigated for a zinc carboxylate of a synthetic rosin compound. Two experimental procedures are presented to measure the reaction rates (gravimetry of exposed resin samples, and atomic absorption spectrometry of liquid samples). A kinetic rate expression was obtained for the rate. The formation of copper resinate during cuprous oxide dispersion in the presence of the zinc carboxylate was also measured. 40 refs. (WSCA Item Number 05/07313)

KIWI J & NADTOCHENKO V: Evidence for the mechanism of photocatalytic degradation of the bacterial wall membrane at the titanium dioxide by attenuated total reflection (ATR)/Fourier transform infrared (FTIR) spectroscopy. (Langmuir 2005, Vol 21 No 10, 4631-41.)
Photocatalytic peroxidation of components of the Escherichia coli cell and of some of its components, within porous titanium dioxide films, was investigated by an infrared spectroscopic technique, which permitted identification of products. Fast reactions of the generated charge carriers were monitored by laser kinetic spectroscopy, which revealed the reactivity of the positive photochemical sites. Peptidoglycan was the most resistant class of membrane wall components. 42 refs. (WSCA Item Number 05/07302)

Reviews of the following books also appeared in the November 2005 issue of WSCA: the full book reviews can be read on the Library Catalogue page of the PRA web site.

ANON: BP Statistical Review of World Energy 2005. (BP plc, London 2005, 41 pp. (Also www.bp.com/statisticalreview).)
(WSCA Item Number 05/07647)

ANON: Adhesives Market UK 2005. (AMA Research Ltd, Cheltenham 2005, 126 pp. Price £595.00.)
(WSCA Item Number 05/07648)

For further information on WSCA please contact the Editor: Dr Norman Morgan

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WSCA Highlights of the Month - October 2005

The October 2005 issue of WSCA contains abstracts of 732 articles including the following examples:

Section 55 Fouling and Microbiological Attack

DALSIN J & MESSERSMITH P B: Bioinspired antifouling polymers. (Materials Today 2005, Vol 8 No 9, 38-46.)
Experimental efforts that demonstrate the use of mussel adhesive protein-mimetic polymers for reducing or preventing fouling of surfaces are presented. Dihydroxyphenylaniline-functionalised polyethylene glycol, a N-substituted glycine oligomer coupled to a short functional peptide and grafting directly on a surface are considered. The postulation is noted that non-fouling surfaces should be electrically neutral, hydrophilic, and possess hydrogen bond acceptors but not hydrogen bond donors; although exceptions to these rules have been observed, many polymers with antifouling properties possess most of these traits. 94 refs. (WSCA Item Number 05/06571)

Section 63 Paints, Etc for Specific Uses

KOEPSEL R, LELE B & RUSSELL A J: Reactive bioplastics: enzymes in polymer matrices. (Proc. European Coatings Conf. 'Smart Coatings IV', Berlin 2005, 87-100.)
The properties of proteins imbedded in polymers were investigated with the goal of producing bioplastic smart coatings. The basic bioplastic design centres on the multipoint incorporation of proteins and enzymes within a polyurethane matrix. Under sufficiently mild conditions the activity of the enzyme may be maintained. Bioplastic formulations were produced which were able to perform a number of enzymatic functions, decontaminate chemical agents, and specifically bind bacteria or proteins. Coatings made from these materials retained a portion of the enzymatic activity but they were highly impermeable and this limited the access of the enzyme to its substrate. New chemistries were developed to modify the proteins and allow them to migrate to the surface of the coating during curing. This resulted in a significant increase in activity. The effect was also examined of creating porous films using a water-soluble polyether as porogen. Other investigations involved capture of enzyme by antibody or avidin in the film, and capture of Escherichia coli. (WSCA Item Number 05/06608)

ZHOU Z, WU B & MEYERHOFF M E: Novel heparinised polyurethane coatings with controlled nitric oxide release. (ACS, Div. of PMSE, Papers 2005, Vol 93, 260-1.)
The development is presented of a new generation of nitric oxide releasing polyurethane coatings that employ diazenium diolate nitric oxide release chemistry in combination with surface-immobilised active heparin. Continuous nitric oxide release may be initiated upon water uptake by the polyurethane, yielding nitric oxide release from a lipophilic nitric oxide donor (N-diazenium diolated dibutylhexanediamine) that is doped within an underlying polymeric layer of the coating. At the same time, on the outermost surface of the trilayer coating (the lowest layer being a dense polyurethane layer), porcine heparin is tethered to the surface via a polyethylene oxide (PEO) spacer with amide linkages. 11 refs. (WSCA Item Number 05/06614)

Section 71 Properties and Testing Methods

OTTS D B, CUEVA-PARRA L A, PANDEY R B & URBAN M W: Film formation from aqueous polyurethane dispersions of reactive hydrophobic and hydrophilic components: spectroscopic studies and Monte Carlo simulations. (Langmuir 2005, Vol 21 No 9, 4034-42.)
The combination of internal reflection infrared imaging spectroscopy with attenuated total reflectance Fourier transform infrared spectroscopy and atomic force microscopy, etc, revealed further details of surface morphology and compositional variation across the water-borne film thickness. The polyurethane was applied as a 45% solids composition having an isocyanate/hydroxyl ratio of 2.0. The coating contained both hydrophobic and hydrophilic components, which generated roughness by a stratified deposition at the film/air interface. The simultaneous stratification of hydrophobic components, together with evaporation of water caused a meta-stable interfacial layering and consequent dewetting of the surface. Roughness was enhanced by higher concentrations of water in the cross-linking film. 22 refs. (WSCA Item Number 05/06726)

Section 79 Radiation Curing

SUBRAMANIAN R, RATCLIFF K, GAMBINO C & DVORCHAK M: Low energy ultraviolet-A radiation-curable refinish primers and clear coats. (J. Coatings Tech. 2005, Vol 2 No 15, 38-41.)
The use of ultraviolet-A (UVA) radiation-curable raw materials for primers and clear coats was investigated. Various aliphatic urethane acrylates were screened for the right combination of coatings properties using high throughput screening. The few predicted formulations were subjected to rigorous performance tests to identify combinations that have fast dry time, adhesion, and sanding characteristics. An ultraviolet A-curable refinish solvent-borne primer was successfully developed and evaluated. The primers had fast cure time combined with good solvent resistance and sanding characteristics. The initial salt-fog and humidity resistance evaluation showed good performance compared to a traditional epoxy primer system. A combination of hard and soft urethane acrylics resulted in a UV-curable refinish clear coat with good coating performance. (WSCA Item Number 05/06802)

Reviews of the following books also appeared in the October 2005 issue of WSCA: the full book reviews can be read on the Library Catalogue page of the PRA web site.

CORNELL R M & SCHWERTMANN U: Iron Oxides: Structure, Properties, Reactions, Occurrences and Uses. (Second, Completely Revised and Extended Edition). (Wiley-VCH Verlag GmbH, Weinheim (Germany) 2003, 703 pp. (ISBN: 3-527-30274-3). Price £180.) (WSCA Item Number 05/06915)

HAMLEY I W (EDITOR): Developments in Block Copolymer Science and Technology. (John Wiley & Sons Ltd, Chichester 2004, 367 pp. (ISBN 0-470-84335-7). Price £95.00 (142.50 euros).) (WSCA Item Number 05/06916)

HOLMBERG K, JONSSON B, KRONBERG B & LINDMAN B: Surfactants and Polymers in Aqueous Solution, 2nd Edition. (John Wiley & Sons Ltd, Chichester 2003,545 pp. (ISBN 0-471-49883-1). Price £85.00 (127.50 euros).) (WSCA Item Number 05/06917)

SCHIERS J & LONG T E: Modern Polyesters: Chemistry and Technology of Polyesters and Copolyesters. (John Wiley & Sons Ltd, Chichester 2003, 750 pp. (ISBN 0-471-49856-4). Price £185.00 (277.50 euros).) (WSCA Item Number 05/06918)

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WSCA Highlights of the Month - September 2005

The September 2005 issue of WSCA contains abstracts of 711 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

ADDAMO M & OTHERS Preparation and photoactivity of nanostructured titanium dioxide particles obtained by hydrolysis of titanium(IV) chloride. Colloids & Surfaces 2005, Vol A265 No 1, 23-31.
The preparation of nanostructured polycrystalline titanium dioxide photocatalysts obtained by hydrolysis of titanium(IV) chloride in very mild conditions is reported. Several samples were prepared as suspensions or colloidal dispersions by using titanium(IV) chloride/water volume ratios ranging between 1:1 and 1:100. The samples were characterised by X-ray diffraction analysis, specific surface area determination, diffuse reflectance spectroscopy and scanning electron microscopy. 4-Nitrophenol photodegradation was used as a probe reaction to test the photoactivity of the catalysts. Some samples revealed a photoactivity higher than that of commercially-produced materials in similar experimental conditions and the most photoactive one was that prepared by using a titanium(IV) chloride/water volume ratio equal to 1:50. A dialysis process was performed in some cases to reduce the number of chloride ions present in the system. The presence of chloride ions appeared to be dramatically detrimental for commercially-produced materials while a lower influence was found for the home-prepared samples. 51 refs. (WSCA Item Number 05/05474)

Section 19 Halogenated Polymers

DREHER W R, SINGH A & URBAN M W Effect of perfluoroalkyl chain length on synthesis and film formation of fluorine-containing colloidal dispersions. Macromol. 2005, Vol 38 No 11, 4666-72.
The development of a new family of colloidal dispersions that exhibit non-spherical shapes and are capable of forming stable polymeric dispersions and films is reported. Heptadecafluorodecyl methacrylate, heptadecafluorodecyl acrylate, heptadecafluoro-1-decene (FD), heptafluorobutyl acrylate and heptafluorobutyl methacrylate were copolymerised with methyl methacrylate and n-butyl acrylate monomers, resulting in the formation of stable colloidal dispersions that contain up to 8.5% (weight/weight) of fluorine-containing polymer. The presence of a specified fluorinated surfactant (used together with sodium dodecyl sulphate) allowed for production of non-spherical, monomodal colloidal particles possessing fluorine-containing blocks near the exterior of the particles. Characterisation methods showed that the length of the perfluoroalkyl side chain in fluorine-containing monomers was directly related to surface concentration levels in coalesced films. The investigations also showed that the incorporation of each fluorine-containing monomer generates surface properties with enhanced water repellency as well as significant decreases of the kinetic coefficient of friction. 36 refs. (WSCA Item Number 05/05574)

Section 54 Patents: Weathering, Corrosion, Etc

MEIJI UNIVERSITY Silicon-containing zinc-rich hybrid Japanese lacquer composition. Japanese Unexamined Patent 2004/256696.
A method is disclosed to provide a new rustproof coating composition which has improved adhesion to steel materials as a result of a synergistic effect of the chelation of iron by the anion effect of Urushiol contained in a Japanese lacquer liquid and a sacrificial anode effect of zinc powder. A rust preventive agent compatible with environment may be obtained by adding a silane compound or a silicate compound with one substitution and three functionalities to a purified Japanese lacquer with reduced moisture (Kurome-Urushi) or a Japanese lacquer prepared by heating the same at 90-100 deg. C for 2-3 hours to hybridise them, and adding zinc powder alone or in combination with aluminium powder, magnesium powder, a suspending agent and an appropriate amount of a diluent. (WSCA Item Number 05/05787)

Section 75 Pollution and Utilisation of Wastes

TURLEY P A, FENN R J, RITTER J C & CALLOW M E Pyrithiones as antifoulants: environmental fate and loss of toxicity. Biofouling 2005, Vol 21 No 1, 31-40.
The environmental fate and the loss of toxicity of two important antifouling actives, zinc pyrithione and copper pyrithione were investigated using a bioassay study and an outdoor microcosm study. The bioassay used inhibition of the growth of a marine diatom (Amphora coffeaeformis) to measure the toxicity of the pyrithiones over time in sterile, natural, and sediment-supplemented sea water. In natural sea water and sediment-supplemented sea water in the dark and in sterile sea water exposed to light, growth inhibition was reduced at rates corresponding to the rapid degradation rates for zinc and copper pyrithones measured in previous aquatic metabolism, die-away, and photolysis studies. Similarly, the bioassay results from sterile sea water in the dark were consistent with the slower degradation rates measured in abiotic hydrolysis studies. In addition to corroborating the rapid degradation of pyrithione upon exposure to light or sediment, the loss of toxicity indicated that the degradation products were not toxic at the concentrations produced from the dose, which was much higher than predicted environmental concentrations. To supplement environmental fate studies designed to elucidate single-pathway transformations, a microcosm study was conducted to integrate all of the degradation pathways. The study used two sediment and water systems, one of which was dosed during the day and the other at night. The pyrithione degraded rapidly in the water phase, with very little accumulation in the sediment. Pyridine-2-sulphonic acid (I) and carbon dioxide were the only detectable degradation products 30 days after dosing. Aquatic toxicity studies with (I) showed no observable effect at concentrations at least three orders of magnitude higher than those for either zinc pyrithione or copper pyrithone. As a result, the worst-case environmental concentration of (I) is expected to be far below the no observable effect concentration. 25 refs. (WSCA Item Number 05/06027)

Section 80 Patents: Radiation Curing

DSM IP ASSETS BV Radiation-curable coating composition for optical fibre with reduced attenuation loss. European Patent Application 1497380, 33 pp. (Also PCT WO 03/091346).
A radiation-curable coating composition is disclosed. It comprises a radiation-curable oligomer comprising a backbone derived from polypropylene glycol and a dimer acid-based polyester polyol. The coating composition, when cured, has a hardening temperature of -10 deg. C to about 20 deg. C and a modulus measured at the hardening temperature of lower than 5.0 MPa, or has a hardening temperature of from -20 deg. C to about 30 deg. C and a modulus measured at the hardening temperature of lower than 20.0 MPa, or has a hardening temperature of lower than about 30 deg. C and a modulus measured at the hardening temperature of lower than 70.0 MPa. Use of the coating as a primary coating for optical fibres is also claimed. The temperature at which the coating material begins the transition from its rubbery state (soft) to its glassy state (hard) is referred to as 'the hardening temperature'. (WSCA Item Number 05/06058)

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WSCA Highlights of the Month - August 2005

The August 2005 issue of WSCA contains abstracts of 729 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

ANON Nanotechnology in coatings: good things come in small packages. Coatings Mag. 2005, Vol 26 No 2, 14 (8 pp).
Developments by various companies are presented. Nanomaterials, particles that are 80,000 times smaller than the width of a human hair, are being used to enhance paint and coating functionalities and to create a new generation of 'smart' products. The current round of new nano-based coatings emerging on the market place fall into the 'enhanced function' category. These are coatings formulated with nanoparticles such as zinc oxides, tin oxides and silicates, which impart significantly better scratch and abrasion resistance. Since these nanoparticles are under 100 nm, they are below the wavelength of visible light. Therefore they may be incorporated into clear coats without affecting the translucency of the formulation. Nano-based coatings are also playing a role in cleaning up the environment. A specific company has launched a new paint that soaks up noxious gases from motor vehicles; the paint is based on the company's spherical nanoparticles (30 nm wide) of titanium dioxide and calcium carbonate. The polysiloxane base is considered porous enough to allow nitrogen oxide to diffuse through it and adhere to the titanium dioxide particles. The particles absorb ultraviolet light and use the energy to convert nitrogen oxides to nitric acid. This acid is either washed away in the rain or neutralised by the alkaline calcium carbonate particles. (WSCA Item Number 05/04747)

Section 17 Oxygenated Polymers

RAMAN V I & PALMESE G R Nanoporous thermosetting polymers. Langmuir 2005, Vol 21 No 4, 1539-46.
Porous, cured epoxy/methacrylate gels were prepared by reactive encapsulation of solvent (tetrahydrofuran was suitable) at 60 deg. C. During the process the solution became turbid, indicating phase separation. The gels were extracted with pressurised carbon dioxide and dried with the supercritical solvent. These steps avoided collapse of the porous structure. Pore size ranged from 1 to 50 nm, depending on the content of solvent. Furthermore, chemical reactivity of the pores could be introduced by grafting various functional groups, e.g, acrylate. (WSCA Item Number 05/04845)

Section 20 Patents: Halogenated Polymers

LORD CORP Room temperature-curable fluoropolymer coating. United States Patent 6838407: Off. Gaz. 2005, Vol 1290 No 1.
A coating composition is disclosed that is made from a mixture of two parts. The first part comprises a solution in organic solvent of a graft-reaction product of a fluoroelastomer (selected from a polymer of 1,1-dihydroperfluorobutyl acrylate, copolymer of vinylidene fluoride and chlorotrifluoroethylene, copolymer of vinylidene fluoride and hexafluoropropylene, copolymer of vinylidene fluoride and hydropentafluoropropylene, copolymer of tetrafluoroethylene and propylene, terpolymers of vinylidene fluoride, hexafluoropropylene, and tetrafluoroethylene, terpolymer of vinylidene fluoride, tetrafluoroethylene and perfluorovinyl ether, terpolymer of vinylidene fluoride, tetrafluoroethylene, and propylene, and a terpolymer of vinylidene fluoride and hydropentafluoropropylene and tetrafluoroethylene), and a grafting agent grafted to the fluoroelastomer via a primary amine group. The grafting agent contains at least one active hydrogen-containing group. The second part comprises a curing agent that contains at least one isocyanate group or a group bearing an isocyanate group that bonds to an active hydrogen-bearing group of the fluoroelastomer, and a reactive cross-linking group that bonds to another active hydrogen-bearing group of the fluoroelastomer. (WSCA Item Number 05/04865)

Section 35 Water-borne Paints and their Components

CASTAING J-C, BOUSSEAU J N & BEURDELEY P Gloss and hardness build-up during water evaporation. Comparison of three binders: latex, alkyd emulsions and water-borne hybrid binder. Proc. PRA 8th Nurnberg Congress 'Creative Advances in Coatings Technology' (PRA, Teddington/Vincentz Verlag, Hanover/Forschungsinstitut fur Pigmente und Lacke, Stuttgart), Nurnberg 2005, Vol 1, 223-30.
An acrylic latex paint, a medium-oil alkyd based on soyabean fatty acids and a hybrid based on an alkyd/acrylic polymer dispersion were investigated. Drying behaviour of the three water-borne systems was examined by laser profilometry and colorimetry to monitor roughness and flocculation/coalescence, respectively. (WSCA Item Number 05/04910)

Reviews of the following books also appeared in the August 2005 issue of WSCA: the full book reviews can be read on the Library Catalogue page of the PRA web site.

DOLPHIN T (EDITOR) Product Finishing Directory and Handbook 2005-2006. Hill Media Ltd, Tring (Herts) 2005, 282 pp.
(WSCA Item Number 05/05471)

GOODSHIP V & OGAR E O Polymer Processing with Supercritical Fluids. Rapra Review Reports, Rapra Technology Ltd 2004, Vol 15 No 8, 138 pp. (ISBN 1-859-494-7). Price œ85 ($153, 136 euros).
(WSCA Item Number 05/05472)

WEAVER R E F Practical Math for Protective Coatings Industry. SSPC 03-05. SSPC: The Society for Protective Coatings, Pittsburgh 2003, 231 pp. (ISBN 1-889060-74-7). Price $65.00 (SSPC Members $45.50).
(WSCA Item Number 05/05473)

For further information on WSCA please contact the Editor: Dr Norman Morgan

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WSCA Highlights of the Month - July 2005

The July 2005 issue of WSCA contains abstracts of 702 articles including the following examples:

Section 49 Pretreatment and Application

KNUSEL C Flow simulations in automobile coating. Besser Lackieren 2005, February 18, Automotive Supplement, 5.
The use of computational fluid dynamics (CFD) in relation to coating processes in the motor vehicle industry is described. The technology is used to simulate a number of processes, including the heating curves for automobile components and the air flow in spray booths. (In German) (WSCA Item Number 05/04353)

Section 53 Weathering, Corrosion, Etc

EL-MAHDY G A & KIM K B Monitoring of initial stages of atmospheric zinc corrosion in simulated acid rain solution under wet/dry cyclic conditions. J. Sci. Eng. Corros. 2005, Vol 61 No 5, 420-7.
The exposure of zinc samples in simulated acid rain solution was investigated under periodic wet/dry conditions using an alternating current impedance technique. The influence of relative humidity (RH), temperature, and surface inclination on the atmospheric corrosion of zinc is described. The polarisation resistance reciprocal decreased rapidly during the initial stages and slowly attained a steady state as the overall exposure time progressed. The experiment results showed a pronounced dependence of reciprocal polarisation resistance on relative humidity. Two main components were identified in the corrosion products on zinc surfaces at 95% RH, namely hydrozincite and hydrated zinc hydroxysulphate; at 60% RH the main products were hydrozincite and simonkolleite. Exposure in the presence of carbonate anions gives rise to more protective corrosion products than it does in a nitrate anion solution. 45 refs. (WSCA Item Number 05/04388)

PROSEK T & THIERRY D Mobility and mode of inhibition of chromate at defected areas of organic coatings under atmospheric conditions. J. Sci. Eng. Corros. 2004, Vol 60 No 12, 1122-33.
The ability of chromate as an anticorrosive pigment incorporated into primer coatings to inhibit the corrosion of galvanised steel was investigated using cell modelling conditions at defects of painted sheets. The experiments were performed at different temperatures (4, 22 and 40 deg. C) and chloride concentrations (1 mmole/litre and 10 mmole/litre) with coatings releasing 20-100 mg/sq. m chromate per 48 hours. The chromate pigment was strontium chromate. After 1-48 hours, the solutions were analysed by ion chromatography and the metals samples were examined using Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX) and X-ray absorption near edge structure spectroscopy (XANES). The results showed that chromate was transported from the pigmented primer to the bare metal surface and formed a protective layer on it; moreover, an enrichment of the pit centres with chromium was found with EDX, suggesting the ability of chromate to seek the active, or formerly active, corrosion sites and preferentially adsorb at these locations. 29 refs. (WSCA Item Number 05/04404)

Section 87 Legislation and Other Official Publications

ROGERS A European Union restrictions on solvents will counter substance abuse. Health & Safety at Work 2005, Vol 27 No 5, 9.
A directive approved by members of the European parliament on 13th April 2005 requires that the toluene content of adhesives and spray paints sold to the public must be less than 0.1 %. The US Environmental Protection Agency has proposed that the reference concentration of toluene could be eased to 10 mg/cu. m. Meanwhile, the new European Union directive will also restrict the use of trichlorobenzene which is used mainly as an intermediate in the manufacture of herbicides and as a process solvent in closed systems. To a lesser extent, it is used as a dye carrier and corrosion inhibitor. (WSCA Item Number 05/04737)

Reviews of the following books also appeared in the July 2005 issue of WSCA.

ANON Flooring Industry Yearbook 2005. Marketplace Publishing Ltd, London 2005, 106 pp. Price £9.95. (WSCA Item Number 05/04743)

JILEK J H Directory of Paint Manufacturers in Central & Eastern Europe. PRA Coatings Technology Centre, Hampton 2005 . (Package includes a printed version and CD-ROM). Price £300.00. (WSCA Item Number 05/04744)

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WSCA Highlights of the Month - June 2005

The June 2005 issue of WSCA contains abstracts of 599 articles including the following examples:

Section 36 Patents: Water-borne Paints and their Components

ICI Thickened aqueous coating compositions containing film-forming polymeric binder. European Patent Application 1368438, 43 pp. (Also PCT 02/062904).
Thickened water-borne coating compositions are disclosed. They provide films with reduced water sensitivity. The compsns. contain film-forming binder and high proportion of autoxidisable macromolecular (associative) thickener, with groups hydrophilic at chosen pH, having low shear viscosity on dispersion in water, preferably a cellulose-free autoxidisable thickener. A preferred technique for introducing the autoxidisable groups involves copolymerising a derivative of a long-chain unsatd. fatty acid. The copolymerisable compound containing the fatty acid may be the diester formed by reacting the long-chain fatty acid with the oxirane group in an unsatd. glycidyl carboxylate. Other techniques exist for introducing autoxidisable moieties into a thickener macromolecule. The compsn. may contain a polyunsatd. compound (specifically claimed is a compound that contains polybutadiene moieties). The compsn. also contains drier which catalyses autoxidation of long-chain unsatd. fatty acids or copolymerised diesters and polybutadiene groups. Preparation and uses are also claimed. (WSCA Item Number 05/03568)

Section 53 Weathering, Corrosion, Etc

DEVAPAL D, PACKIRISAMY S, KORULLA R M & NINAN K N Atomic oxygen-resistant coating from poly(tetramethyldisilylene-co-styrene). J. Appl. Polym. Sci. 2004, Vol 94 No 6, 2368-75.
A polydisilahydrocarbon, namely, poly(tetramethyldisilylene-co-styrene), synthesised from dimethyldichlorosilane and styrene in a 2 to 1 mole ratio under dechlorination conditions was evaluated as an atomic oxygen (AO)-resistant coating for polyimide film and carbon/polyimide composite. Exposure of the polymer coating on a quartz plate to an atomic oxygen fluence of 2.1 times ten to the power twenty-one atoms/sq. cm resulted in practically no mass loss, indicating the atomic oxygen resistance of the polymer. A 10% solution of the polymer in toluene was applied on aluminised polyimide film to obtain a coating thickness of 5 micrometres on the unaluminised surface. In a similar way, the coating was applied on a carbon/polyimide composite. The coated and uncoated samples of film and carbon-polyimide composite were exposed to atomic oxygen in a plasma barrel system and losses were investigated. Scanning electron microscopy (SEM) suggested that the coating offers good protection to the substrates. The formation of cracks on some portions of the coating was noticed. 47 refs. (WSCA Item Number 05/03688)

TUKEN T, YAZICI B & ERBIL M Polypyrrole/polythiophene coating for copper protection. Progr. Org. Coat. 2005, Vol 53 No 1, 38-45.
A polypyrrole film was formed on copper electrode by electrochemical synthesis from monomer-containing oxalic acid aqueous solution. Then a polythiophene top coating was synthesised electrochemically on the polypyrrole-coated copper electrode. It was shown that the polypyrrole/polythiophene coating could provide important protection against copper corrosion for considerable immersion periods. 31 refs. (WSCA Item Number 05/03714)

Section 69 Analytical Methods

BELL S E J, FIDO L A, SPEERS S J & ARMSTRONG W J Rapid forensic analysis and identification of 'lilac' architectural finishes using Raman spectroscopy. Appl. Spectrosc. 2005, Vol 59 No 1, 100-8.
The potential of Raman spectroscopy to discriminate between architectural finishes (household paint) was investigated using a test set of 51 'lilac' paints and three different excitation wavelengths. The spectra obtained with visible excitation typically displayed a series of intense Raman bands on a featureless fluorescence background but the spectra of all the paints examined had essentially identical bands. With 785 nm excitation, although the same bands that dominated the 514 nm spectra were still observed, other bands with comparable intensity also appeared. The two strongest scattering constituents were identified as a dioxazine dye, Violet 23, and beta-copper phthalocyanine. A scatter plot of the intensities of marker bands for these constituents (normalised to the strong rutile bands that were always present) showed that, despite the fact that the sample set spanned a wide range of rutile/dioxazine dye/phthalocyanine ratios, many of the samples had very similar ratios and could not be discriminated. However, all the samples (even those with similar relative proportions of the main constituents) could be discriminated on the basis of their minor constituents, either by manually measuring band intensities or through the creation and searching of spectral libraries. 33 refs. (WSCA Item Number 05/03833)

Section 88 Standards and Specifications

BRITISH STANDARDS INSTITUTION Paints and varnishes: determination of the volatile organic compound content of low volatile organic compound emulsion paints (in-cans volatile organic compounds). BS EN ISO 17895, 2005, 11 pp. (ISBN 0-580-45889-X). Price œ64.00.
A gas chromatographic method is specified that is applicable to volatile organic compound contents between 0.01% and 0.1% (by mass). The organic compounds in a small amount of thinned sample are fully evaporated in a head-space injector and then are determined by gas chromatographic analysis. (WSCA Item Number 05/04036)

Books

SSPC SOCIETY FOR PROTECTIVE COATINGS Systems and Specifications: SSPC Painting Manual. Volume 2. 2005 Edition. SSPC: The Society for Protective Coatings, Pittsburg 2005, 900 pp. (SSPC 04-13, ISBN 1-889060-81-X). Price $250.00 ($175.50 SSPC members).
The new 2005 edition of 'Systems and Specifications' is a complete, up-to-date collection of SSPC standards, guides, specifications, and other consensus documents for the cleaning and preparation of steel and concrete surfaces, the selection and application of protective coating systems, the composition and performance capabilities of paints and coatings, and other materials, processes, and technologies. The new edition comes as a set of tab-indexed, loose-leaf documents held in a three-ring binder. It is also available as a collection of searchable, printable pdf files on CD-ROM. (WSCA Item Number 05/04042)

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WSCA Highlights of the Month - May 2005

The May 2005 issue of WSCA contains abstracts of 648 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

ANON: Synthetic aluminium silicate reduces titanium dioxide. (Ind. Minerals 2005, No 449, 25.)
Advantages of synthetic aluminium silicate are noted, as are its higher binder demand and the need to be mixed with coarse fillers such as talc to create matt finish. In USA and Asia, natural raw materials such as china clay are used to provide the necessary properties; in Europe, and especially Germany, synthetic aluminium oxide is used. (WSCA Item Number 05/02796)

Section 06 Patents: Solvents, Plasticisers and Intermediates

FACULTES UNIVERSITAIRES NOTRE-DAME DE LA PAIX: Nanocomposites: products, process for obtaining them and uses thereof. ( European Patent Application 1483201, 28 pp. (Also PCT 03/078315).)
Nanocomposites are disclosed which comprise polymers, carbon nanotubes and layered silicate nanoparticles. Processes for obtaining the nanocomposites, and their uses in fire-resistant structures, as flame retardants, as antistatic materials, as anti-crack materials in surface coatings, etc, are also claimed. (WSCA Item Number 05/02855)

Section 17 Oxygenated Polymers

HEDFORS C & OTHERS: Thiol end-functionalisation of poly(epsilon-caprolactone), catalysed by Candida antarctica lipase B. (Macromol. 2005, Vol 38 No 3, 647-9.)
Syntheses are described of polycaprolactone having a single thiol end group on each polymer chain. Initiation of enzyme-catalysed ring-opening polymerisation of caprolactone by mercaptoethanol provided the thiol group at the start of polymerisation, when a number-average molecular weight of 3000 was obtained. Alternatively, the hydroxyl end group of polycaprolactone, again catalytically prepared in presence of the lipase enzyme, was reacted with either 3-thiobutyrolactone or 3-mercaptopropionic acid (I). Both these terminations yielded an omega-mercapto-polyester carboxylic acid. Reaction with (I), which was carried out without solvent, provided the highest number-average MW, of about 6800. 17 refs. (WSCA Item Number 05/02906)

Section 63 Paints, Etc for Other Specific Uses

SCHEERDER J, VISSCHER N, NABUURS T & OVERBEEK A: Novel, water-based fluorinated coatings with good anti-graffiti properties. (Proc. Federation of Societies for Coatings Technology 82nd Annual Meeting 'Challenge, Change, Opportunity', Chicago (Illinois) 2004, Paper 6, 16 pp.)
Novel water-based, cross-linkable fluorinated polymers are discussed that form coatings with good anti-graffiti properties. The synthesis of the binders from acrylic monomers and the surface and bulk properties of their coatings are described, cross-linking being by isocyanates. The surface properties were characterised in terms of surface tension (from static contact angle measurements) and the distribution of the fluorine atoms throughout the coating (X-ray photoelectron spectroscopy (XPS)). Bulk properties were investigated by determination of cross-link density by dynamic mechanical thermal analysis (DMTA). The effect of the cross-linking conditions on the cross-link density and the anti-graffiti properties are discussed. The results indicated that a combined action of surface and bulk properties provides these coatings with their good anti-graffiti properties. The applicability of these polymers as protective coatings for metal and concrete surfaces was demonstrated. 11 refs. (WSCA Item Number 05/03136)

Section 88 Standards and Specifications

AMERICAN SOCIETY FOR TESTING AND MATERIALS: Standard practice for evaluating accelerated efflorescence of latex coatings. (ASTM D 7072-04, 2005 Annual Book of ASTM Standards, Vol 06.02, 854-5.)
This practice covers the evaluation of the degree to which a latex paint resists the formation of efflorescence and alkali burn-out on the exposed paint surface. Panels known to have a level of salts capable of being easily and quickly transported to the paint surface are used. Since tinted paints show the efflorescence most clearly, all white paints should be tinted before application. The panel is placed face down over the surface of the test chamber which contains heated water, so that moisture condenses and remains on the painted surface of the panel for a period of 48 hours. After drying at ambient conditions, the panels are rated for the degree of efflorescence which has formed. (WSCA Item Number 05/03418)

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WSCA Highlights of the Month - April 2005

The April 2005 issue of WSCA contains abstracts of 703 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

FELLER A & CHRISTIAN H-D: Filling up paint. (Polym. Paint Col. J. 2005, Vol 195 No 4484, 26 (4 pp).)
The use is discussed of precipitated aluminium silicates which, on account of their marked fine-particle nature and porosity, possess a high oil absorption value, which in turn reduces the critical pigment volume concentration of the formulation. The high oil absorption of the aluminium silicates is not necessarily detrimental to the mechanical properties of an emulsion paint. Aluminium silicates therefore allow more efficient utilisation of titanium dioxide white pigments in emulsion paints. Use of aluminium silicate with other fillers is discussed, as is replacement of calcined kieselguhr and use with talc. (WSCA Item Number 05/02094)

Section 05 Solvents, Plasticisers and Intermediates

DOWLING A P: Development of nanotechnologies. (NanoToday 2004, December, 30-5.)
A summary is provided of the key findings and recommendations of a Royal Society/Royal Academy of Engineering report on nanotechnology. The report is enthusiastic about the great potential benefits of nanotechnologies. Uncertainties associated with the health and environmental impacts of free, manufactured nanoparticles and nanotubes are discussed. It recommends research to understand better their toxicology and exposure pathways and actions to restrict exposure of humans and the environment to free, manufactured nanoparticles and nanotubes until they are better understood. The need for public dialogue about the development of nanotechnologies is highlighted. The original report is available from http://www.nanotec.org.uk/FinalReport.htm 13 refs. (WSCA Item Number 05/02131)

Section 15 Hydrocarbon Polymers

CAILLE J-R, DEBUIGNE A & JEROME R: Controlled radical polymerisation of styrene by quinone transfer radical polymerisation (QTRP). (Macromol. 2005, Vol 38 No 1, 27-32.)
Radical polymerisation of styrene was controlled at 100 deg. C, in presence of phenanthrenequinone and a catalytic amount of cobalt(II) acetylacetonate. Effective resumption of styrene polymerisation by preformed oligomer, predictability of molecular weight from the molar monomer/quinone ratio, etc, were observed up to at least 50% conversion. A four-step reaction mechanism, involving initial formation of a persistent, coloured, radical, from the quinone and cobalt(II), is suggested. The investigation is being extended to other ortho-quinones and catalysts, in order to define potential and limits of the reaction. 20 refs. (WSCA Item Number 05/02163)

Section 75 Pollution and Utilisation of Wastes

HARINO H & OTHERS: Accumulation of butyltin compounds in benthic biota of the Mersey Estuary. (Marine Pollution Bull. 2005, Vol 50 No 2, 222-5.)
Samples were collected from the southern shoreline of the Mersey Estuary and a range of key benthic indicators were sampled for butyltins (BT) including sediment-dwelling polychaetes Nereis diversicolour and bivalves S. plana, Mascoma balthica, M. arenaria, Cerastiderna edule, together with epibenthic mussels Mytilus edulis, snails L littorea, and seaweed Fucus vesiculosus. Concentrations of butyltin compounds determined in benthic organisms at individual sites are tabulated and the average composition of butyltin for each species is shown. Total butyltin concentrations, and in particular tributyltin (TBT), in sediment-dwelling bivalves were generally higher than those in the epibenthic molluscs. Butyltin concentrations were highest in M. arenaria and were dominated by tributyltin. 24 refs. (WSCA Item Number 05/02671)

Section 88 Standards and Specifications

PAGELLA C, FUMI D, GALLI R & DE FAVERI D M: Italian standard for coatings in the food industry. (Proc. PRA 'Hygienic Coatings and Surfaces' Conf, Paris 2005, Paper 4, 11 pp.)
An outline of the recently-issued standard UNI 11021 to assess the characteristics of coatings in a food manufacturing or distribution environment is presented, and experimental results obtained during its development are provided. Existing standard test methods for controlling hazardous substances release potential and to assess coatings properties such as dirt pick-up, hiding power, wet scrub resistance or resistance to chemicals and cleaning agents are used or adapted, and new specific test methods were developed for cleanability, release of odours and mildew growth resistance. 16 refs. (WSCA Item Number 05/02795)

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WSCA Highlights of the Month - March 2005

The March 2005 issue of WSCA contains abstracts of 692 articles including the following examples:

Section 18 Patents: Oxygenated Polymers

SIGMA COATINGS BV: Air-drying paint compositions comprising carbohydrate-based polyesters. ( European Patent Application 1470178, 33 pp. (Also PCT 03/064498).)
The invention relates to a polyester obtainable by transesterification of a carbohydrate or an acyl ester thereof, an alkyl ester of a drying fatty acid, semi-drying fatty acid or mixture thereof, and an alkyl ester of a non-aromatic polycarboxylic acid. The carbohydrate is, e.g, sucrose or trehalose. The invention further relates to the preparation of the polyester by a process comprising the step of transesterification or interesterification. Use of the polyester as a binder in paints and varnishes is also claimed. (WSCA Item Number 05/01498)

Section 64 Patents: Paints, Etc for Other Specific Uses

CREAVIS GESELLSCHAFT FUR TECHNOLOGIE UND INNOVATION MBH: Self-cleaning coating from hydrophobic structures and method for its production. ( European Patent Application 1249280, 8 pp. (Also US Patent Application 20020150724).)
Self-cleaning surfaces with (partially) hydrophobic structure are disclosed. They comprise (sub-)microparticles of specified size protruding from matrix comprising heat- and/or radiation-cured coating, the particles having nanometre-scale protuberances/depressions/fissures. (Doped) silicate, metal oxide, silica, metallic powder and/or polymeric fissured particles may be used and applied to wet uncured coating film. Application processes and coated substrates are also claimed. (In German) (WSCA Item Number 05/01733)

Section 71 Other Properties and Testing Methods

FATH A: Effect coatings: easy to clean, dirt resistant, release and lotus effect properties. (Metalloberflaeche 2004, Vol 58 No 9, 46-50.)
Methods of testing easy-to-clean and release coatings are discussed, considering self-cleaning/soiling resistance, contact angles and water pearling, rub resistance, easy-to-clean properties determination and fingerprint resistance. (In German) (WSCA Item Number 05/01821)

Section 81 Economics

BHASKARAN R, PALANISWAMY N, RENGASWAMY N S & JAYACHANDRAN M Review of differing approaches used to estimate the cost of corrosion (and their relevance in the development of modern corrosion prevention and control strategies). Anti-Corros. 2005, Vol 52 No 1, 29-41.
Four well-known approaches to analysis of cost of corrosion, i.e, the Uhlig method, the Hoar method (based mainly on direct interaction with industries and corrosion experts), NBS-BCL input/output method and net present value method are considered in detail. Figures are provided for various countries (Australia, India, Japan, UK and USA) and industry sectors. It is concluded that all of the approaches enabled an estimation of the direct cost of corrosion but that, however, the indirect cost of corrosion invariably is worked out on a speculative basis. 18 refs. (WSCA Item Number 05/01971)

Section 85 Education, Training and Information

LEE S, CHANG L-M & CHEN P-H: Performance comparison of bridge coating defect recognition methods. (J. Sci. Eng. Corros. 2005, Vol 61 No 1, 12-20.)
Several defect recognition methods are evaluated in relation to their rust recognition performance. The methods involve image analysis and fall into two categories. One method uses artificial intelligence methods such as neural networks and fuzzy logic as the backbone for recognition, whilst the others apply statistical approaches to detect rust areas. Illumination is considered in some of the proposed methods to determine how it affects the recognition results. 11 refs. (WSCA Item Number 05/02061)

Reviews of the following books also appeared in the March 2005 issue of WSCA: the full book reviews can be read on the Library Catalogue page of the PRA web site.

ANON: Environmental Consultancy Directory 2005. (Environmental Data Services Ltd, London 2005 2005, No 12, 140 pp. (ISBN 0-907673-22-8). Price £60.) (WSCA Item Number 05/02088)

IMPACT MARKETING CONSULTANTS INC: Rauch Guide to the US Paint Industry. Fourth Edition. 2004-06. (Impact Marketing Consultants Inc, Vermont 2004, 316 pp. (ISBN 0-932157-12-3). Price $595 (Download Softcopy $895).) (WSCA Item Number 05/02089)

INFORMATION RESEARCH LTD: Profile of the Central and Eastern European paint industry. 2nd Edition. (Information Research Ltd, London 2004, 243 pp. Price 3000 euros.) WSCA Item Number 05/02090)

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WSCA Highlights of the Month - February 2005

The February 2005 issue of WSCA contains abstracts of 698 articles including the following examples:

Section 39 Adhesive Compositions

GRIGSBY W J, FERGUSEN C J, FRANICH R A & RUSSELL G T: Evaluation of latex adhesives containing hydrophobic cores and polyvinyl acetate shells: potential to improve polyvinyl acetate performance. (Internat. J. Adhes. Adhesives 2005, Vol 25 No 2, 127-37.)
Various experimental polyvinyl acetate latices containing relatively rigid polystyrene (PS) domains were investigated in order to evaluate whether the presence of polystyrene domains improves the performance, especially the creep resistance, of polyvinyl acetate adhesives. The effects of a range of polystyrene contents, polystyrene/polyvinyl acetate morphologies and core/shell polymerisation approaches were examined by evaluating thin-film mechanical properties and adhesive performance. The results showed that up to 50% polystyrene (by mass) may be incorporated into a polyvinyl acetate latex without compromising adhesive strength. Mechanical testing of films indicated the presence of polystyrene maintains film performance at elevated temperature (60 deg. C). Polymers formed using a chain transfer agent during the second-stage styrene polymerisation had a concentric core/shell morphology and these performed better than either copolymers having an acorn morphology or a simple blend of polystyrene and polyvinyl acetate. Incorporation of polystyrene domains into a commercial polyvinyl acetate adhesive was also examined. 20 refs. (WSCA Item Number 05/00872)

Section 63 Paints, Etc for Other Specific Uses

BIEVER C: Get to Mars in a month with a solar super-sail. (New Sci. 2005, Vol 185 No 2484, 23.)
It is proposed that a spacecraft equipped with a solar sail coated with a specially formulated paint could reach Mars in a month. The suggestion arose from work on solar sails in which a sail exposed to microwave radiation experienced a stronger force on the sail than expected from photon impact. It was discovered that heat from the microwave beam caused carbon monoxide to be released from the surface, and the additional force arose from the recoil of the gas molecules. The proposed system involves the use of a solar sail coated with a paint which releases a light gas such as hydrogen on exposure to high temperature, the heat being provided by a powerful microwave beam projected from the earth. Recoil of the released gas from the surface of the sail would accelerate the spacecraft to high speed in a relatively short time. (WSCA Item Number 05/01064)

Section 67 Mechanical and Rheological Properties

TYAGI S, LEE J Y, BUXTON G A & BALAZS A C: Using nanocomposite coatings to heal surface defects. (Macromol. 2004, Vol 37 No 24, 9160-8.)
Calculations from molecular dynamics simulations, of a surface having a nanoscopic notch and which is coated with a polymer film containing a nano-sized filler, indicated that a relatively large fraction by volume would become situated in the notch. A depletion attraction between the surface and the particles is induced within the molten polymer; by varying the size of the nanoparticles, it was determined that the depletion attraction between the particles and the notch is more pronounced for the larger particles. The morphology derived from the simulation was used as input to the lattice model, from which mechanical properties of the coating were determined. It was found that localisation of the particles in the notch reduced stress at the notch tip. 32 refs. (WSCA Item Number 05/01140)

Section 73 Industrial and Other Hazards

SONG L, SEEGER A & SANTOS-SACCHI J: On membrane motor activity and chloride flux in the outer hair cell: lessons learned from the environmental toxin tributyltin. (Biophys J. BioFAST 2004, December 13. (Available at http://www.biophysj.org/cgi/rapidpdf/biophysj.104.053579v1).)
The effect of tributyltin on intracellular chloride exchange across the outer hair cell lateral membrane in the ears of mammals was examined. Guinea pigs were used in the study. It was concluded that tributyltin had rapid and profound effects on outer hair cell non-linear capacitance, which are directly related to tributyltin's ability to transport chloride across the membrane. This is shown to result in reduced cochlear amplification, and a reduction in auditory sensitivity. The results are said to identify a new environmental threat to marine mammal communication. (WSCA Item Number 05/01236)

Section 79 Radiation Curing

NEO W K, CHAN-PARK M B, GAO J X & DONG L: Effects of silicone acrylate on morphology, kinetics and surface composition of photopolymerised acrylate mixtures. (Langmuir 2004, Vol 20 No 25, 11,073-83.)
The curing of photopolymerisable acrylate compositions as films on a nickel substrate, was investigated by X-ray photoelectron spectroscopy. The major component was an oligoethylene glycol diacrylate. Some of the compositions also contained up to 5% of a silicone hexaacrylate. In these, the slower-curing siliconised component phase-separated as micelles, which migrated to the metal/resin interface. The influence of the initial components on gelation time and the composition at the metal interface were quantified by a designed experiment. Statistical predictive models for new compositions were also provided. (WSCA Item Number 05/01284)

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WSCA Highlights of the Month - January 2005

The January 2005 issue contains abstracts of 700 articles including the following examples:

Section 02 Patents: Pigments, Extenders, Dyestuffs and Phosphors

BAYER CHEMICALS AG: Pigment compositions. ( European Patent Application 1454964, 8 pp.)
Pigment preparations are disclosed. They comprise at least one pigment, at least one polyethyleneimine which is alkoxylated (especially ethoxylated and propoxylated and/or butoxylated), and at least one condensation product. The condensation product is based on aromatics that are sulphonated, aldehydes and/or ketones, and optionally one or more compounds selected from non-sulphonated aromatics, urea and urea derivatives. (In German) (WSCA Item Number 05/00022)

Section 07 Driers and Minor Additives

KNOEF J: Use of coating additives in environmentally friendlier coatings. (Proc. 9th Symposium on Paints, (Association of Greek Chemists), Athens 2004, 119-31.)
Recent developments regarding the additives on offer and how they are used are discussed: special consideration is paid to the use of additives in non-volatile organic compound (non-VOC) and water-borne paints. Topics include coalescing agents, thickeners, anti-skinning agents, cobalt-free driers, steric stabilisation, etc. (WSCA Item Number 05/00053)

Section 36 Patents: Water-borne Paints and their Components

SK KAKEN CO: Water paint composition for interior use. ( Japanese Unexamined Patent 2004/002647.)
A method is disclosed to provide a paint with good storage stability, and capable of forming a coating nice to touch or smell and with good physical characteristics in relation to moisture absorption, desorption, or the like. A mixture is produced of 100 parts by wt. (in terms of solid content) of a resin liquid cationic aqueous dispersion having pH not higher than 7, and 10-500 parts by wt. of vegetable particulates. The vegetable particulates are preferably bleached vegetable particulates. The use of vegetable particulates different in bleach degree, or in colour, enables expression in various colours. (WSCA Item Number 05/00164)

Section 55 Fouling and Microbiological Attack

WIEGEMANN M & WATERMANN B: Impact of desiccation on the adhesion of barnacles attached to non-stick coating. (Biofouling 2004, Vol 20 No 3, 147-53.)
The influence of desiccation of the barnacle adhesive on measurements of adhesion strength of settled organisms, e.g. barnacles, used to assess the effectiveness of fouling-release coatings on ships' hulls, was investigated. The shear forces required to remove barnacles of the genus Balanus increased during the course of desiccation up to the point when the barnacles suddenly self-detached. The increase was thought to be due to the rising cohesive strength of the adhesive. Growing tensile forces within the weakly cross-linked adhesive, however, are suggested to have led to self-detachment. The shear forces required to remove barnacles of the genus Elminius were generally low and did not differ significantly during the course of desiccation. The different results may be attributed to specific base morphologies. It was concluded that measuring the adhesion strength of members of the Balanidae on non-stick surfaces in air could produce flawed results due to the influence of desiccation of the barnacle adhesive. The investigations have also provided new insights into the characteristics of barnacle adhesive. 17 refs. (WSCA Item Number 05/00355)

Section 87 Legislation and Other Official Publications

ANON: Drugged paint: cocaine as thickener. (Farbe Lack 2004, Vol 110 No 10, 10.)
Colombian authorities seized 10 tonnes of building paints just before they were loaded on to a container ship, finding the paint suspiciously thick. Analysis proved the 'thickener' to have been high grade cocaine. (In German) (WSCA Item Number 05/00684)

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Previous years: 2004