World Surface Coatings Abstracts (WSCA) - Highlights 2008

January · February · March · April · May · June · July · August · September

WSCA Highlights of the Month - October 2008

The October 2008 issue of WSCA contains abstracts of 624 articles including the following examples:

Section 53 Weathering, Corrosion, Etc

SINGH D D N & YADAV S Role of tannic acid-based rust converter on formation of passive film on zinc-rich coating exposed in simulated concrete pore solution. Surface & Coatings Tech. 2008, Vol 202 No 8, 1526-42.
Reinforcing elements were coated with tannic acid-based rust converter and then coated with zinc dust paint. Prior to the application of the rust converter the surfaces of the specimens were prerusted in pure water, water solution of sodium chloride and water solution of sodium sulphate. Electrochemical measurements were performed using a test electrolyte obtained by dissolving sodium hydroxide, calcium oxide and potassium hydroxide in double distilled water, the solutions being blended with chloride ions. Zinc-rich coating over a layer of tannic acid-based rust converter was observed to have considerable improvement in corrosion resistance exposed to synthetic concrete pore solution having 1% chloride ions. It was established that this improvement is due to the increase in pH of the corroding interface as a result of outward diffusion of acidic components of unreacted rust converter from the coating. A passive layer of hydrozincite was observed to form on the coated surface which provides effective protection to the rebars. The investigations also indicated that due to the formation of compact passive film during initial periods of exposure of zinc coating in concrete environments, there exists little change of deposition of bulky corrosion products at the coating/concrete interface. The rust converter was prepared by mixing phosphoric acid, tannic acid and acetone. 41 refs. (WSCA Item Number 08/05907)

Section 71 Other Properties and Testing Methods

WANG X, BERGGREN M & INGANAS O Dynamic control of surface energy and topography of microstructured conductive polymer films. Langmuir 2008, Vol 24 No 11, 5942-8.
Microstructured surfaces of polymers, including conductive or insulating polymers, were prepared in order to control their surface energy and topography. Pillar and mesh-like patterned polypyrrole and insulating polymer on, e.g, poly(3,4-ethylenedioxythiophene)/polystyrenesulphonate surfaces serve as surface switches, which may be electrochemically modified from dewetting to wetting conditions, with marked changes in contact angle, by varying the topography. The method may have application in electronically controlled cell growth. 25 refs. (WSCA Item Number 08/06038)

Section 73 Industrial and Other Hazards

YU Y & OTHERS Exploring the immunotoxicity of carbon nanotubes. Nanoscale Res. Lett. 2008, Vol 3 No 8, 271-7.
Some existing studies assessing carbon nanotubes' toxicity to immune system are discussed, including both in vivo and in vitro studies, and causes of immunotoxicity and its control are discussed. It is concluded that available data strongly suggest that carbon nanotubes enter cells, cause production of reactive oxygen species, and interact with the immune systems. A better understanding of the mechanisms of carbon nanotubes' interaction with immune systems considered to be needed for developing and optimising biocompatible nanomedicine carriers. 56 refs. (WSCA Item Number 08/06053)

Section 79 Radiation Curing

CHENG S & CHASSER A High performance ultraviolet-curable organic/inorganic hybrid coatings for plastics. Proc. RadTech UV & EB Conf, Chicago 2008, Paper, 5 pp.
Organic/inorganic nanohybrid coatings were formulated by incorporating different types of inorganic nanoparticles/acrylate dispersions into a control acrylate mixture. The appropriate addition of inorganic nanoparticles provides greatly enhanced abrasion resistance and chemical resistance, and as the inorganic content increases, the hybrid system exhibits good ceramic-like abrasion resistance while maintaining good adhesion to plastics substrates. Due to the small particle size and homogeneous particle dispersion, the coatings exhibit good optical clarity. The introduction of inorganic nanoparticles provides improved eco-friendliness due to the lowered usage of petroleum based chemicals in coating products. Potential applications for these high-performance hybrid coatings include consumer electronics, appliances, motor vehicle parts, and optical lenses. (WSCA Item Number 08/06072)

Reviews of the following books also appeared in the October 2008 issue of WSCA: the full book reviews can be read on the library catalogue page of the PRA web site.

CZAJKA C Europaint 2009. Etai, Gentilly (France) 2008, 456 pp.
(WSCA Item Number 08/06204)

DOLPHIN T (EDITOR) Product Finishing Directory and Handbook 2008-2009. Hill Media Ltd, Tring (Herts) 2008, 337 pp.
(WSCA Item Number 08/06205)

GUILD R Victorian House Book: a Practical Guide to Home Repair and Decoration. 4th Edition. Sheldrake Press, London 2008, 320 pp. (ISBN 978-1-873329-40-6). Price œ30.00.
(WSCA Item Number 08/06208)

HALL C H Chemistry of Paints and Paint Vehicles. Van Nostrand Co, New York 1906 (Reprint published by Read Books, 2008), 134 pp. (ISBN 978-1-40979-341-0). Price œ3.22.
(WSCA Item Number 08/06209)

PROVDER T & BAGHDACHI J (EDITORS) Smart Coatings. ACS Symposium Series 957, American Chemical Society, Washington 2007, 202 pp. (ISBN 978-0-8412-7429-7). Price œ90.00.
(WSCA Item Number 08/06211)

SCHWALM R Ultraviolet Coatings: Basics, Recent Developments and New Applications. Elsevier, Amsterdam 2007, 310 pp. (ISBN 978-0444-52979-4). Price œ120.
Item Number 08/06213)

TALBERT R Paint Technology Handbook. CRC Press, Boca Raton (Florida) 2007, 240 pp. (ISBN 978-1-57444-703-3). Price œ73.14.
(WSCA Item Number 08/06214)

TRACTON A A (EDITOR) Coatings Technology: Fundamentals, Testing, and Processing Techniques. CRC Press, Boca Raton (Florida) 2007, 408 pp. (ISBN 1-4200-4406-0). Price œ75.99.
(WSCA Item Number 08/06215)

For further information on WSCA please contact Dr Norman Morgan

top

WSCA Highlights of the Month - September 2008

The September 2008 issue of WSCA contains abstracts of 620 articles including the following examples:

Section 09 Natural Resins

ANON New biorefineries could provide raw material for coatings: lignin. JCT CoatingsTech 2008, Vol 5 No 3, 28-9.
Lignin production and properties is discussed, it being noted that biorefineries converting linocellulosic biomass to ethanol may provide another material with potential value for additive, resin, and coating producers. Sulphur-free lignin exhibits desirable properties for numerous applications such as coatings, adhesives, etc. (WSCA Item Number 08/05050)

Section 30 Patents: Cellulose Products

FRAUNHOFER GES FORDERUNG ANGEWANDTEN FORSCHUNG EV; FIT GMBH Starch-based coating materials with controllable dissolution behaviour, their production and use. World (PCT) Patent Application 20(WSCA Item Number 08/014914, 40 pp.
A coating and/or potting material is disclosed, which comprises a starch derivative which has been O-alkylated at least partly with an ethylamino functionality at a hydroxyl group. A process for producing the coating and/or envelope material is also claimed. Use of the material as a protective coating, specifically as an anti-graffiti coating, is also claimed. Specific claims relate to insolubility in water at pH of 8 or greater, and to increased solubility at pH less than 8. (In German) (WSCA Item Number 08/05101)

Section 35 Water-borne Paints and their Components

HOLTMANN F & LIGHT M Water-based coatings: meeting current and future technical demands. Farbe Lack 2008, Vol 114 No 7, 24 (2 pp).
Some of the current and future demands placed on water-based coatings are described. It is expected that there will be requirements for water-based coatings to dry faster, be more durable, and be made using renewable materials. Some of the other factors that are important for producers of water-based coatings, including the rising costs of energy and raw materials, are also outlined. (In German) (WSCA Item Number 08/05108)

Section 37 Solventless and Powder Coatings

SCHMIDT T Increasing the scratch resistance of powder coatings. JOT/Oberflaeche 2008, Vol 48 No 4, 56-7.
A new technique is described which is reported to increase the scratch resistance of powder coatings by over 100 percent. The new process uses hard particles, which are coated in a soft shell. The soft shell prevents problems during the powder production and application process, and it is only during the curing of the coating that the soft shell melts, leaving the hard particles in the coating to improve the scratch resistance. This development opens the way for a significant extension of the areas of application for powder coatings. (In German) (WSCA Item Number 08/05128)

Section 79 Radiation Curing

AMERIO E & OTHERS Scratch resistance of nano-silica reinforced acrylic coatings. Progr. Org. Coat. 2008, Vol 62 No 2, 129-33.
Organic/inorganic hybrid coatings were obtained by a dual-curing process combining the sol/gel reaction with the UV-induced polymerisation technique by starting from bisphenol A ethoxylate (15 ethylene oxide/phenol) dimethacrylate (BEMA), as organic network former, methacryloyloxypropyltrimethoxysilane (MEMO), as coupling agent and tetraethoxysilane (TEOS), as inorganic silica network precursor. Good scratch-resistant coatings were obtained by the UV and sol/gel dual-curing process. In comparison, coatings with poor scratch resistance were obtained by dispersing preformed nano-silica into the acrylic resin, indicating the key role played by the morphology of the inorganic filler and its interaction with the organic matrix. 19 refs. (WSCA Item Number 08/05454)

top

WSCA Highlights of the Month - August 2008

The August 2008 issue of WSCA contains abstracts of 607 articles including the following examples:

Section 02 Patents: Pigments, Extenders, Dyestuffs and Phosphors

BRETON SPA Process for the production of titanium dioxide using aqueous fluoride. European Patent Application 1841694, 23 pp.
A process is disclosed for the production of titanium dioxide. The process comprises the steps of reacting the titanium ore containing iron with an aqueous ammonium fluoride solution, filtering the aqueous dispersion thus obtained with consequent separation of a solid residue and an aqueous solution containing titanium salts, subjecting the aqueous solution thus obtained to hydrolysis, the hydrolysis comprising a first stage at pH 7.0-8.5 and a second stage at pH 10.0-13.0, filtering the aqueous dispersion thus obtained and subjecting the solid residue to pyrohydrolysis, the pyrohydrolysis comprising a first stage at a maximum temperature of 450 deg. C and a second stage at a maximum temperature of 1000 deg. C. (WSCA Item Number 08/04381)

Section 17 Oxygenated Polymers

STAVA V, VESELY D & KALENDA P Catalytic effects of transition metals in the form of the salts of organic acids in the cross-linking of alkyds. Pig. Resin Tech. 2008, Vol 37 No 2, 67-72.
The drying effects were investigated of cobalt, manganous and mixed salts for their catalytic action in cross-linking reactions occurring during the creation of an alkyd resin film. It was found that cobalt was extremely active at the beginning of the autooxidation reaction as well as during the later stages of film curing. After 60 days of measurements, the greatest hardness of all the monitored systems was displayed by the film containing cobaltous drier. The catalytic abilities of the manganese may be activated with organic ligand, e.g, 2,2'-dipyridyl. The properties of such a system during the initial stages of autooxidation are comparable to those of the driers of cobalt. If suppler and softer coatings are required, manganese driers offer an optimum solution. 12 refs. (WSCA Item Number 08/04448)

Section 63 Paints, Etc for Other Specific Uses

RAJ R Coatings for medical application. Paintindia 2008, Vol 58 No 4, 75 (14 pp).
The use of coatings in both short-term and long-term medical applications is described, including coating characteristics, classification, application methods, polymers, polymer degradation, etc. Short-term uses include medical seals, pressure sensors and transducers, guide-wires, catheters, mandrels, brain probes, and needles. Long-term or permanent uses include electronic circuits, cardiac-assist devices, and pipette and microplate trays and covers. Methods of applying the coating are discussed. Biodegradable polymers for medical applications are listed. The general criteria for selecting a polymer for use as a biomaterial is to match the mechanical properties and the time of degradation to the need of the application. Specific polymers, including polyglycolide, polylactide, poly(epsilon-caprolactone), poly(dioxanone), poly(glyconate) and polyphenylene, are discussed. Polymers for coating drug-eluting stents and for tablets are discussed in detail. 11 refs. (WSCA Item Number 08/04674)

Section 73 Industrial and Other Hazards

BAO V W W & OTHERS Synergistic toxic effects of zinc pyrithione and copper to three marine species: implications on setting appropriate water quality criteria. Marine Pollution Bull. 2008, Vol 57 No 6, 616-23.
The combined effects of zinc pyrithione and copper used in antifouling paints as a substitute for tributyltin, on marine organisms, were investigated. The toxicities of zinc pyrithione alone and in combination with copper to the diatom Thalassiosira pseudonana, polychaete larvae Hydroides elegans and amphipod Elasmopus rapax were examined. Zinc pyrithione and copper resulted in a strong synergistic effect with the isobologram interaction parameter being greater than 1 for all test species. The combined toxicity of zinc pyrithione and copper was successfully modelled using the non-parametric response surface and its contour. Such synergistic effects may be partly due to the formation of copper pyrithione. It is considered inadequate to assess the ecological risk of zinc pyrithione to marine organisms solely based on the toxicity data generated from the biocide alone. To better protect marine resources, it is advocated to develop appropriate water quality criteria for zinc pyrithione with the consideration of its compelling synergistic effects with copper at environmentally realistic concentrations. 35 refs. (WSCA Item Number 08/04780)

Section 87 Legislation and Other Official Publications

KAMBANIS S Determination of the polymeric nature of rosin derivatives for REACH (registration, evaluation, authorisation and restriction of chemicals). Proc. 29th FATIPEC Congress, Ghent (Belgium) 2008, Paper 92, 8 pp.
The polymeric nature of rosin derivatives was determined in order to assess whether they are exempt from REACH (registration, evaluation, authorisation and restriction of chemicals) regulations. It is noted that according to the latest REACH proposal, exempted polymers must fulfil the requirements that at least 50% (area) of the molecular weight distribution curve must be larger than the sum of three monomer units plus another monomer unit covalently bound to each other, and that the molecules with the same molecular weight (single gel permeation chromatography peak) must represent less than 50% of the molecular weight distribution. Examination of molecular weight parameters of rosin esters showed that they are not polymers, while maleic, fumaric and phenolic-modified derivatives are polymers provided that their acid values are low. (WSCA Item Number 08/04957)

top

WSCA Highlights of the Month - July 2008

The July 2008 issue of WSCA contains abstracts of 602 articles including the following examples:

Section 53 Weathering, Corrosion, Etc

JUBETE E, LIAUW C M, JACOBSON K & ALLEN N S Degradation of carboxylated styrene/butadiene rubber-based water-borne paints. I. Effect of talc filler and titanium dioxide pigment on ultraviolet stability. Polym. Deg. & Stabil. 2007, Vol 92 No 8, 1611-21.
The photodegradation was investigated of coatings containing a proprietary rubber binder and containing talc and rutile titanium dioxide (both separately and in combination). An imaging chemiluminescence method was also used to depth profile the oxidation. Self-supported films (2 mm thickness) were cast. Both the wavelength of the UV source and the presence of filler and pigment were found to influence the degradation process and the propensity for cross-linking of the surface. At relatively low levels (less than 50 phr), talc showed an optimum UV stabilising effect at the irradiated surface. At higher levels the stabilising effect reduced, attributed to the presence of iron impurities in the talc. After prolonged exposure a reduction in solvent swelling and increase in Tg was observed. This was also manifest by surface hardening, being attributed to loss of the 1,4-trans- and 1,2-vinyl unsaturation in the polymer backbone due to cross-linking of the copolymer. Increase in talc level was shown to temper this Tg increase and imaging luminescence studies showed that the talc protected the core regions of the film from oxidation via a physical barrier effect. As expected the presence of titanium dioxide significantly retarded surface oxidation with a slow growth of carbonyl absorption bands being in evidence. Whilst a similar loss of vinyl unsaturation was observed, surface hardening (cross-linking) was not observed indicating that a different mechanism was in operation. (WSCA Item Number 08/04071)

Section 55 Fouling and Microbiological Attack

VAN DEN BULCKE J & OTHERS Three-dimensional imaging and analysis of infested coated wood with X-ray submicron computed tomography. Internat. Biodet. Biodeg. 2008, Vol 61 No 3, 278-86.
Coated pine sapwood infested with the blue stain fungus Aureobasidium pullulans was visualised in three dimensions using X-ray computed tomography with submicrometre resolution. Scanning and subsequent reconstruction took less than half an hour and generated an intensity matrix of 483 by 483 by 322 voxels. In addition to imaging and localisation of the fungus, accessibility of the wood structure, basic anatomical properties of the wood and characteristics of the coating were determined on the three-dimensional data stack using image processing. It is considered that X-ray biotomography as a non-invasive imaging tool for scientists in general, and mycologists, wood and coating researchers in particular, offers new possibilities for revealing science. 40 refs. (WSCA Item Number 08/04102)

Section 69 Analytical Methods

SAVAGE L M Fluorescence correlation spectroscopy helps to track individual molecules during polystyrene formation. Photonics 2008, Vol 42 No 2, 97-8.
Research by a Belgian university and a German institute is summarised (Woll D and others, Angewandte Chemie International 2008, Vol 47 No 4, 783-7) in which workers combined fluorescence correlation spectroscopy (FCS) with wide-field microscopy to watch polymerisation transpire at the single molecule level. They studied styrene, polymerising the material either with or without cross-linker, and using probes comprising derivatives of perylenediimide, a very stable fluorescent dye with high quantum yield. The scientists followed the polymerisation of the styrene molecules by detecting changes in the diffusion constant of dye molecules as they moved first among the monomers in solution, then within the matrices formed by the emerging polymer. As polymerisation proceeded, the motion of the dye molecules slowed because they had less freedom of movement. (WSCA Item Number 08/04180)

Section 79 Radiation Curing

PATEL K I, PARMAR R J & PARMAR J S Novel binder system for ultraviolet-curable coatings based on tobacco seed (Nicotiana rustica) oil derivatives as a renewable resource. J. Appl. Polym. Sci. 2008, Vol 107 No 1, 71-81.
The use of tobacco seed (Nicotiana rustica) oil in the synthesis of radiation-curable coatings was investigated. The alcoholysis of oil in various ratios with polyhydroxyl compounds was performed to prepare novel polyols, and these different polyols were reacted further with excess polyisocyanate to produce isocyanate-terminated prepolymers. The prepolymer were further reacted with hydroxyethyl methacrylate to produce urethane acrylate oligomers. The radiation-curable coating compositions were then prepared by the mixing of these oligomers with different reactive diluents, photoinitiators, and activators. These coating compositions were examined for their various physical and film characteristics, and certain coating compositions from tobacco seed oil were found to show good overall coating properties. The work was done in the light that most polymers industrially produced nowadays are based on petroleum, which is a limited resource. Developing new procedures for making polymers based on natural renewable resources is a current theme. 20 refs. (WSCA Item Number 08/04259)

Reviews of the following books also appeared in the July 2008 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 June 2008. BP plc, London 2008, 48 pp. (Available from www.bp.com). (WSCA Item Number 08/04360)

MITTAL K L (EDITOR) Contact Angle, Wettability and Adhesion, Volume 5. VSP BV, Leiden & Boston 2008, 308 pp. (ISBN 978-90-04-15864-1). Price 133.00 euros, $194.00. (WSCA Item Number 08/04361)

PFAFF G & OTHERS Special Effect Pigments. 2nd Revised Edition. Vincentz Network, Hannover 2008, 218 pp. (ISBN 978-3-86630-905-0). Price 149 euros. (WSCA Item Number 08/04362)

POTH U Automotive Coatings Formulation. Vincentz Network, Hannover 2008, 237 pp. (ISBN 978-3-86630-904-3). Price 119 euros. (WSCA Item Number 08/04363)

top

WSCA Highlights of the Month - June 2008

The June 2008 issue of WSCA contains abstracts of 636 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

MOORES S New titanium dioxide process breakthrough. Ind. Minerals 2008, No 489, 22.
A greener, faster and cheaper processing technique to extract titanium dioxide pigment from ilmenite and rutile feedstock is discussed. It is claimed that the new process will yield 97% purity titanium dioxide compared with the industry average of 85% through the established sulphate and chloride processes. The process involves three key steps. Complex mineral ores are roasted in air in the temperature range of 800-900 deg. C in the presence of alkali to change their chemical structure, in the first step. Any impurities are washed off in a bath of running water, leached with acid, and safely recovered to produce valuable new by-products for industrial uses. The synthetic rutile left behind is then reacted with 20 times less the usual amount of chlorine gas to produce white titanium dioxide powder. (WSCA Item Number 08/03152)

Section 07 Driers and Minor Additives

GRAYSTONE J Progress in the development and evaluation of coating additives. Proc. PRA Additives for Coatings Conf. 'Innovation in Formulation', Frankfurt 2008, Paper 1, 20 pp.
A review is presented that considers examples of developments that have been necessary for additives to maintain their crucial role in the current economic and environmental climate. Influential factors, nanotechnology, microencapsulation, sol/gel techniques, adapting to changing binder technology, development for environmental and sustainability reasons, additives to facilitate colour delivery, newer methodologies for evaluating additives, combinatorial methods, service life prediction, etc are considered. The demand for additives in the coatings industry has never been higher due to legislative pressures and the move to compliant coatings that are sustainable and have minimal environmental impact. New functionality is also required for both established and emerging markets. New additives are being released on the market to meet these demands but pressure is being placed on formulators for evaluation and exploitation. Development is aided by new instrumental techniques and, under some circumstances, in deploying combinatorial methodologies of experimentation. Improved methods for service life prediction are able to shorten the timescale of development and improve confidence in long-term performance. 54 refs. (WSCA Item Number 08/03222)

Section 73 Industrial and Other Hazards

BONNARD N, FALCY M, JARGOT D & PASQUIER E 1-Methoxy-2-propanol and its acetate. Fiche Toxicol. No 221, 2008, 6 pp. (ISBN 978-2-7389-1662-2, Institut National de Recherche et de Securite, available from www.inrs.fr). Print version 2 euros.
Toxic/fire hazards are described together with relevant French regulations, first-aid, precautions in storage and handling, physical and chemical properties, detection and determination in air, European Union, French, German and US exposure limits, and uses. Risk phrases and Chemical Abstracts registry, etc numbers are provided. The compounds are irritants to humans for mucous membranes in the case of exposure above 100 ppm; a central nervous system effect is only apparent at concentrations above 1000 ppm. No other effects have been published for humans. Reference is made to toxicity of 2-methoxy-1-propanol and its acetate, and to levels in 1-methoxy-2-propanol (acetate). (In French with 23 refs.) (WSCA Item Number 08/03631)

Section 87 Legislation and Other Official Publications

ZHOU H & GE X Registrations for chemicals exported to China. China Chemical Reporter 2008, Vol 19 Nos 4/5, 12-4.
International and Chinese regulations on the use of chemicals are outlined, and the current situation in China is explained. China requires producers or importers of new chemical substances to carry out notification procedures and to obtain environmental administration registration certification before production or import. The evaluation and licence process is described, and the Chinese supervision system is outlined. The scheme applies to pharmaceutical raw materials, cosmetics, food packaging, antiseptics for drinking water and chemicals used in toys. (WSCA Item Number 08/03755)

Section 88 Standards and Specifications

BRITISH STANDARDS INSTITUTION Paints, varnishes and plastics: determination of non-volatile matter content. BS EN ISO 3251, 2008, 16 pp. (ISBN 978-0-580-57647-8, available for purchase at www.bsi-global.com). Price £72.00. (WSCA Item Number 08/03756)

Reviews of the following books also appeared in the June 2008 issue of WSCA: book reviews can be read on the Library Catalogue page of the PRA web site.

ANON Global Industrial Coatings Market 2006-2020. Irfab/PRA, Brussels/Hampton 2008, 686 pages. Price 50,000 euros (PRA member discount is 20%) for full study (CD and printed set), individual chapters also available as Adobe Acrobat (pdf) files. (WSCA Item Number 08/03760)

SEPEUR S, LARYEA N, GOEDICKE S & GROSS F Nanotechnology: Technical Basics and Applications. Vincentz Network, Hannover 2008, 168 pp. (ISBN 978-3-86630-906-7). Price 149.00 euros. (WSCA Item Number 08/03761)

top

WSCA Highlights of the Month - May 2008

The May 2008 issue of WSCA contains abstracts of 611 articles including the following examples:

Section 35 Water-borne Paints and their Components

BROWNING s & OTHERS Extending the open-time of water-borne trim paints. Surface Coatings Austral. 2008, Vol 45 Nos 1/2, 12-8.
It is felt that the open-time and wet-edge time of water-borne trim paints need to be improved in order to obtain the same high quality level that was possible with conventional solvent-borne trim paints. New methods are described that may be used to investigate the fundamental aspects of the open-time of paint films. This was based on a falling wave analyser, which was used for quantitative determination of the levelling and sagging behaviour of paints during drying and curing. The influence of binder and co-binder composition and morphology was also examined. A hybrid polymer was developed with a central self-crosslinking polymer with attached phase inverting lobes. The influence of pigment type and additive package on the application properties was investigated. The new insights led to the development of a new hybrid binder concept that offers significantly improved open time. (WSCA Item Number 08/02697)

Section 55 Fouling and Microbiological Attack

FINLAY J A & OTHERS Settlement of Ulva zoospores on patterned fluorinated and (polyethylene glycol-modified) monolayer surfaces. Langmuir 2008, Vol 24 No 2, 503-10.
Silicon wafers were chemically modified to provide, mainly, squared patterns coated with stripes of alternating perfluoroalkyl or polyoxyethylene chains, on a uniform background of either of the modifications. The stripe width decreased from 500 to 2 micrometres. The Ulva spores were selective in their preference for attachment substrate, greater densities being found on the fluorinated stripes than on the hydrophilic ones. However, their response depended on the stripe width and the chemistry of the background. Spore settlement was reduced on patterns of contrasting wettability, below a certain size, as compared with a totally hydrophobic surface. This result may assist the development of practical antifouling paints. 38 refs. (WSCA Item Number 08/02855)

RENTROP C, WOUTERS M, WILLEMSEN P & DONNELLY G Novel biocide-free nanostructured antifouling coatings: is nano able to do the job? Proc. European Coatings Conf. 'Marine Coatings', Berlin 2008, 109-20.
Clay particles (montmorillonite and sepiolite) were organically modified, and distributed in a sol/gel matrix obtained by hydrolysis of 20 mole % tetraethoxysilane and 80 mole % of methyltriethoxysilane. The effect of the concentration of various modified particles in sol/gel based coatings was examined with respect to morphological changes. Some coatings were exposed to marine bacteria and evaluated by determination of their antifouling and fouling release properties. 20 refs. (WSCA Item Number 08/02857)

Section 79 Radiation Curing

SCHERZER T, KNOLLE W & NAUMOV S Flame retardants as photoinitiators. Farbe Lack 2008, Vol 114 No 1, 40-4.
A new development is described whereby brominated acrylates may be used to initiate the UV curing of acrylate coatings. The chemical background to the process is provided, and experimental results are presented. Brominated acrylates are used as flame retardant additives, and when they are exposed to UV light, radicals are released, which are able to initiate the UV curing of acrylate coatings. Therefore, coatings which contain brominated acrylates, do not require additional photoinitiators. (In German) (WSCA Item Number 08/03033)

Reviews of the following books also appeared in the May 2008 issue of WSCA: book reviews can be read on the Library Catalogue page of the PRA web site.

F BALL & CO Recommended adhesives guide 2008. F Ball & Co, Leek (Staffs) 2008, 94 pp.
(WSCA Item Number 08/03131)

HETHERINGTON L E & OTHERS European Mineral Statistics 2002-2006. British Geological Survey, Keyworth (Nottingham) 2008, 351 pp. (ISBN 978-0-85272-617-4), available at www.mineralsuk.com). Price (print version) £55.00.
(WSCA Item Number 08/03132)

HETHERINGTON L E & OTHERS World Mineral Production 2002-2006. British Geological Survey, Keyworth (Nottingham) 2008, 114 pp. (ISBN 978-0-85272-615-0, available from www.mineralsuk.com). Price (print version) £30.00.
(WSCA Item Number 08/03133)

KROL P Linear Polyurethanes. Koninklijke Brill NV, Leiden (Netherlands) 2008, 256 pp. (ISBN 978-90-04-16124-5). Price 134.00 euros, $200.00. (Orders through Turpin Distribution Services, Biggleswade, UK).
(WSCA Item Number 08/03134)

US DEPARTMENT OF THE INTERIOR & US GEOLOGICAL SURVEY Mineral Commodity Summaries 2008. US Government Printing Office, Washington 2008, 202 pp. (Also available as http://minerals.usgs.gov/minerals/pubs/mcs/2008.pdf).
(WSCA Item Number 08/03135)

top

WSCA Highlights of the Month - April 2008

The April 2008 issue of WSCA contains abstracts of 599 articles including the following examples:

Section 49 Pretreatment and Application

DIJKSTRA D J & OTHERS Relationship between rheological properties and spraying behaviour of polymer dispersions. Macromol. Symposia 2007, Vol 249-250 No 1, 647-53.
The influence of different thickener systems on the spraying behaviour of adhesive-grade polyurethane dispersions was examined. A capillary break-up extensional rheometer was used to determine the extensional viscosity of a number of systems and a comparison was drawn with shear rheology data. A proprietary polyurethane dispersion was used in combination with three different classes of thickener, namely an associative polyurethane thickener, a water-soluble polyacrylate and a water-soluble polyvinylpyrrolidone. The differences in shear rheology for the three different thickeners were found not to be representative of the spraying behaviour. The associative thickener showed only minor changes to the spray pattern, whereas the higher MW soluble thickeners changed the spraying angle and the amount of overspray dramatically. Determination of the elongation viscosity by the rheometer proved to be of little use to predict the spraying behaviour of thickened dispersions. Oscillatory rheometry was shown to be a more appropriate method for measuring the elastic properties of these thickened dispersions. The storage modulus determined in oscillation mode corresponded with the length of the extended spray fan and the reduced overspray determined in spraying experiments. 12 refs. (WSCA Item Number 08/02204)

Section 53 Weathering, Corrosion, Etc

MALLEGOL J, POELMAN M & OLIVIER M G Influence of ultraviolet-weathering on corrosion resistance of prepainted steel. Progr. Org. Coat. 2008, Vol 61 Nos 2/4, 126-35.
An investigation was performed with the aim of showing the influence of the photo-oxidation of painted layers on their barrier effect. Nine different coatings were exposed to ultraviolet radiation in an accelerated weathering device, prior to salt spray exposure. The coatings photo-oxidation was determined by Fourier infrared (FTIR) depth-profiling and the evolution of the barrier properties was followed both by a standard salt spray test and by electrochemical impedance spectroscopy. A good correlation was observed between coating photo-oxidation (FTIR depth profiling), loss of protective effect (impedance measurements) and the resistance to blistering (salt fog exposure) for the different coatings under investigation. It is concluded that depth profiling is of prime importance in determining the degradation of a coating undergoing weathering tests and that measurements of surface gloss may be of less importance. In the paint systems examined, the primers were polyester- or polyurethane-based, and the topcoats were polyester-based. 32 refs. (WSCA Item Number 08/02254)

Section 63 Paints, Etc for Other Specific Uses

MASCARENHAS M Current development of paints for spacecraft applications. Paintindia 2007, Vol 57 No 12, 83 (5 pp).
The requirements that spacecraft paints and coatings must fulfil, together with the types of paints that find use in space research, are discussed. Some of the important characteristics that a paint must display to be successful in space applications are resistance to abrasion and other types of mechanical damage due to micrometeorite impacts, flexible and tough so that it does not crack and flake as it is flexed due to mechanical and thermal strains, resistance to atomic oxygen, ability to withstand vacuum, corpuscular and electromagnetic radiation, resistance to wide temperature extremes, and stability during long-term service in a space environment. Emphasis is given to insulating ceramic coatings, thermal control paints, corrosion-resistant paint, temperature-sensitive and pressure-sensitive paints, and cryogenic paints. 11 refs. (WSCA Item Number 08/02310)

Section 79 Radiation Curing

DAVIDSON R S Medical applications of radiation curing. RadTech News 2007, No 3, 6 (7 pp).
A review is presented on the use of radiation curing and radiation-curable compositions in dentistry, opthalmics, adhesives (for external and internal use), surgery (including implants and equipment), tissue engineering (scaffolds for cell growth), drug delivery, analytical devices, etc. Reference to photopolymerisation is included. (WSCA Item Number 08/02431)

Reviews of the following books also appeared in the April 2008 issue of WSCA: book reviews can be read on the Library Catalogue page of the PRA web site.

BRUNE B (EDITOR) European Coatings Directory 2008. Special Issue: Powder Coatings. Vincenz Network, Hannover 2008, 90 pp.
(WSCA Item Number 08/02521)

HEILIG M Deutsches Taschenbuch fur Maler und Lackierer 2008 (German Handbook for Painters 2008). 2 volumes. Verlag Georg D W Callwey, Munchen 2008, 272, 128 pp. (ISBN 978-3-7667-1753-5). Price 15 euros.
(WSCA Item Number 08/02522)

INDUSTRY STATISTICS LTD World Paint File. Fourth Edition. DMG World Media (UK) Ltd, Redhill (Surrey) 2006, 400 pp. (ISBN 1-84313-025-4). Price £999.00 (1578 euros).
(WSCA Item Number 08/02523)

KUEHNI R G & SCHWARZ A Color Ordered: a Survey of Color Order Systems from Antiquity to the Present. Oxford University Press, New York 2008, 391 pp. (ISBN 978-0-19-518968-1). Price 360.00.
(WSCA Item Number 08/02524)

top

WSCA Highlights of the Month - March 2008

The March 2008 issue of WSCA contains abstracts of 610 articles including the following examples:

Section 02 Patents: Pigments, Extenders, Dyestuffs and Phosphors

OMYA DEVELOPMENT AG Composites of inorganic and/or organic microparticles and nano-dolomite particles. World (PCT) Patent Application 2007/141271, 73 pp.
Composites are disclosed, which comprise inorganic and/or organic pigments and/or fillers in the form of microparticles, the surface of which is coated at least partially with finely divided nano-dolomite with the help of binders based on copolymers comprising as monomers one or more dicarboxylic acids and one or more monomers from the group of diamines, triamines, dialkanolamines or trialkanolamines. A method for producing such composites, aqueous slurries thereof, their use, and the use of the binders for coating the microparticles with nano-dolomite are also claimed. Use of the composites in fillers and coatings, especially paper coatings, is also claimed. (WSCA Item Number 08/01363)

Section 04 Patents: Oils, Waxes and Related Materials

ZHANG G Natural plant type paint and its preparation method. Chinese Patent 1786095.
A natural plant type coating and its preparation method are disclosed. The coating is formed from high-molecular film-forming material, pigment, adjuvant and solvent. It is characterised in that the oil material adopted in the high-molecular film-forming material contains 30-40 parts of linseed oil, 35-45 parts of limonene, 5-15 parts of polybasic alcohol, polybasic acid which comprises 8-15 parts of phthalic anhydride and 2-5 parts of trimellitic anhydride, adjuvant comprising 0.02-0.1 parts of catalyst lithium hydroxide, drier comprising 1-3 parts of composite rare earth, and solvent containing 5-10 parts of pine cone oil and 5-10 parts of terpineol. The raw materials are mixed to obtain the film-forming material. A slurry material is formed by mixing deionised water, 18-35 parts of pigment titanium dioxide, drying, dispersing, anti-freezing, defoaming, anticorrosion and film-forming adjuvants, talc and natural calcium carbonate. 10-20 parts of film-forming material are employed to make emulsion, deionised water, the slurry material and thickening agent are added, and mixed so as to obtain the coating. (WSCA Item Number 08/01375)

Section 22 Patents: Nitrogenous Polymers

SIKA TECHNOLOGY AG Volatile organic compound (VOC) free or low VOC polyurethane coating. European Patent Application 1876196, 19 pp. (Also PCT WO 20(WSCA Item Number 08/000831).
Humidity-hardening compounds containing at least one polyurethane polymer are disclosed. They contain an isocyanate group, at least one polyimine of specified general formula in an amount of at least 22 wt. %, in relation to the sum of the components of the compound which contain the isocyanate group, as well as, if necessary, a polyisocyanate oligomer. The humidity-hardening compound is particularly suitable for providing coatings and linings. The use of the imines makes possible VOC-free or VOC poor compounds, which is a substantial advantage for indoor applications. (In German) (WSCA Item Number 08/01467)

Section 55 Fouling and Microbiological Attack

CHANG Q & OTHERS Bactericidal mechanism of silver/aluminium oxide against Escherichia coli. Langmuir 2007, Vol 23 No 22, 11197-9.
Escherichia coli cells became severely disrupted by contact with the prepared silver/aluminium oxide bactericide. In contrast, little change in the cells resulted from treatment with aqueous silver ions. Furthermore, prior treatment of the binary biocide with superoxide dismutase and/or catalase, which respectively deactivate superoxide anion radicals and hydrogen peroxide, weakened the bactericidal efficacy of the modified aluminium oxide. Hence, it was concluded that the bactericide acted by a catalysed oxidation of the bacterial cells. Ultraviolet irradiation weakened this, whilst blackening the initially white bactericide. This indicated that silver oxide was beneficial for the bactericidal activity. Synergy of the two components in the cell disruption was also identified. 14 refs. (WSCA Item Number 08/01632)

Section 64 Patents: Paints, Etc for Other Specific Uses

ADVANCED CARDIOVASCULAR SYSTEMS INC Bioabsorbable, biobeneficial polyester polymers for stent coatings. United States Patent 7301001: Off. Gaz. 2007, Vol 1324 No 4.
A polymer is disclosed comprising an alcoholic moiety derived from an aliphatic diol, triol, or polyol, an acidic moiety derived from a polycarboxylic acid (I), and a biobeneficial moiety. The biobeneficial moiety is derived from polypropylene glycol, proprietary surfactants, block copolymers comprising polyethylene glycol and polypropylene glycol, hydroxy-functional polyvinylpyrrolidone, dextrin, sodium hyaluronate, hyaluronic acid, elastin, water-soluble heparin, water-soluble elastin, tropoelastin, poly(2-hydroxyethyl methylmethacrylate), heparin, hirudin, sulphonated polystyrene, superoxide dismutase mimetics, antioxidants, or free radical scavengers. The polycarboxylic acid (I) is selected from the acidic moiety derived from at least one diacid selected from straight chain aliphatic diacids having 2 to 20 C atoms, terephthalic acid, fumaric acid, citric acid, citramalic acid, tricarballylic acid, tartaric acid, isophthalic acid, 1,6-bis(p-carboxyphenoxy)hexane, 1,3-bis(p-phenoxycarboxy)propane, 1,4-bis(p-phenoxycarboxy)butane, and oligomeric diacids with anhydride bonds in the backbone. (WSCA Item Number 08/01685)

top

WSCA Highlights of the Month - February 2008

The February 2008 issue of WSCA contains abstracts of 603 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

BURGIO L & OTHERS Spherical copper resinate on Coromandel objects: analysis and conservation of matt green paint. Studies Conservat. 2007, Vol 52, No 4, 241-54.
An unusual green pigment was found on a seventeenth-century kuan cai (Coromandel) lacquer screen at the Victoria and Albert Museum, London. The particles were perfectly spherical and translucent, with the appearance of green fish roe. Analysis revealed that the pigment was a copper resinate, produced by reacting a copper salt with a resin, probably from a Pinus species. The binding medium for the pigment is proteinaceous. In light or olive green areas, the pigment is mixed with lead white, and the paint is glossy and well-preserved. In contrast, in the dark green areas where the pigment was used alone, the paint is matt and powdery and there is significant paint loss and abrasion. The problem of consolidation of the powdery paint, while still preserving the matt appearance of the surface, was resolved by the use of immiscible solvents and consolidant. 45 refs. (WSCA Item Number 08/00716)

SHI X & GAN Z Preparation and characterisation of polypropylene carbonate/montmorillonite nanocomposites by solution intercalation. Europ. Polym. J. 2007, Vol 43 No 12, 4852-8.
Nanocomposites of polypropylene carbonate of stated molecular weight, together with various proportions of organically-modified montmorillonite, exhibited, e.g, tensile strength and a glass transition temperature higher than those of the unmodified silicate. Thus, the improved properties were 23.1 MPa and 34 deg. C, which is 13 deg. higher than that of the polycarbonate alone. The optimum content in the nanocomposites of layered, modified silicate, containing cetyltrimethylammonium cations, was 4% by wt. 20 refs. (WSCA Item Number 08/00735)

Section 03 Oils, Waxes and Related Materials

KOBAYASHI S, UYAMA H, TSUJIMOTO T & KUWABARA M New synthesis of functional polymers using renewable resources from plant oils. ACS, Polym. Preprints 2007, Vol 48 No 2, 830-1.
The production of functional polymeric materials using renewable resources mainly based on plant oils is examined and the lipase-catalysed polyester synthesis from natural alcohols and fatty acids is described together with the green nanocomposite synthesis from plant oils. Thus, reaction of divinyl sebacate with triols such as glycerol, and of sorbitol with divinyl sebacate, and incorporation of unsaturated fatty acid or epoxidised fatty acid in the polyester, are considered in the former synthesis. In the latter, green nanocomposites showing elasticity were prepared as an organic/inorganic hybrid material by acid-catalysed curing of epoxidised plant oils in the presence of organophilic clay or with a silane compound. 12 refs. (WSCA Item Number 08/00772)

Section 53 Weathering, Corrosion, Etc

LEE C-H, SHIN C-S & BAEK K-K Electrochemical impedance spectroscopy studied to evaluate coatings for ballast tanks and splash zones. J. Protect. Coat. Linings 2007, Vol 24 No 10, 17 (3 pp).
Electrochemical impedance spectroscopy (EIS) was adopted to quantitatively and effectively select coating systems having optimised performance for the protection of water ballast tanks of ships and the splash zone of offshore structures. Several epoxy and epoxy/polyurethane coating systems were tested using a wet/dry cyclic exposure to accelerate their degradation. A plausible prediction model for determining the remaining lifetime of coating systems was also proposed. The electrochemical impedance spectroscopy measurements were carried out in natural sea water at room temperature. By using electrochemical impedance spectroscopy it was found possible to predict the lifetime of coatings by determining the time taken for their impedance to fall to about 10 to the power 7 ohms/sq. cm. It was also concluded that the use of temperatures higher than the glass transition temperature (Tg) of the coating to accelerate coating degradation in a wet/dry cyclic test causes unrealistic and unpredictable results. (WSCA Item Number 08/01025)

SHI X, FERNANDO B M D & CROLL S G Concurrent physical ageing and degradation of cross-linked systems in accelerated weathering: examination of thermal cycling and cross-link density effect. Proc. Federation of Societies for Coating Technology '2007 FutureCoat' (ICE 2007) Conf, Toronto 2007, Paper, 19 pp.
Two cross-linked coating systems (polyurethane and epoxy) were investigated in order to compare different chemical composition, their glass transition temperature, and their thermal response in accelerated weathering. During thermal cycling, physical ageing measured by enthalpy recovery exhibited different trends in the two coatings. A rejuvenation mechanism was observed in the coating with a glass transition temperature between the top and bottom limits of the exposure cycle, continued ageing being observed for the coating with a high glass transition temperature. Stress relaxation tests detected ageing and memory behaviour over periods comparable with accelerated weathering cycles. It is considered that when various coatings are evaluated, simply judging their performance under the same weathering environment is not reliable since polymer relaxation behaviour depends on the relationship between the exposure temperatures and the glass transition temperature of each polymer. 41 refs. (WSCA Item Number 08/01031)

A review of the following book also appeared in the February 2008 issue of WSCA: book reviews can be read on the Library Catalogue page of the PRA web site.

STREITBERGER H-J & DOSSEL K-F Automotive Paints and Coatings. 2nd Edition. Wiley-VCH Verlag GmbH, Weinheim 2008, 493 pp. (ISBN 978-3-527-30971-9). Price £110.00 (154.00 euros)
(WSCA Item Number 08/01315)

top

WSCA Highlights of the Month - January 2008

The January 2008 issue of WSCA contains abstracts of 712 articles including the following examples:

Section 01 Pigments, Extenders, Dyestuffs and Phosphors

KROGER N & OTHERS Bio-enabled synthesis of amorphous and crystalline titanium dioxide at ambient temperature and neutral hydrogen ion concentration (pH). ACS, Div. of PMSE, Papers 2007, Vol 96, 71-2.
It was demonstrated that recombinant proteins, encoded by selected regions of silaffin genes from diatoms, exhibit titanium dioxide-forming, as well as silica-forming activities. The substrate was a titanium complex. The unique molecular characteristics of one of the recombinant silaffin enabled the synthesis of rutile titanium dioxide at ambient temperature and pH 7. The protein-induced rutile formation is expected to enable previously inaccessible pathways for the synthesis of photonic materials. (WSCA Item Number 08/00018)

Section 49 Pretreatment and Application

ELLIOTT P T, STEFFENHAGEN M J & GLASS J E Spray applications. III. Assessment of viscosities at high shear rates and dynamic uniaxial extensional viscosities on fan nozzle air sprayability. J. Coatings Tech. Res. 2007, Vol 4 No 4, 341-9.
Water-soluble polymer blends of high molecular volume hydroxyethylcellulose/high molecular volume polyoxyethylene and low molecular volume hydroxyethylcellulose/high molecular volume polyoxyethylene were prepared with similar low shear viscosities but different high shear rate viscosities. The three solutions within a set of blends all had essentially the same low and high shear viscosities, surface tension and elasticity, but different dynamic uniaxial extensional viscosities; this allowed the role of high shear rates and dynamic uniaxial extensional viscosity to be separated in their influence on atomisation and sprayability. It was determined through visual analysis of air spray (55 pounds per square inch, fan nozzle) patterns that the dynamic uniaxial extensional viscosity is the dominant parameter in controlling the atomisation and sprayability of these simple water-soluble polymer blends. It was found that the low molecular volume hydroxyethylcellulose blends with high molecular volume polyoxyethylene produced higher dynamic uniaxial extensional viscosity. 19 refs. (WSCA Item Number 08/00324)

GEHRKE J, DRUMMER B & BAUER H K Powder coating on metal parts using eddy current curing. Besser Lackieren 2007, Vol 9 No 11, 16.
The application of eddy current curing to powder coatings applied to metal parts is described. Eddy current techniques have previously been used for coating removal, and for precleaning, and the results of a research project into their use for curing of powder coatings are provided. The eddy currents generated cause an increase in temperature in the metals to be coated, thus providing sufficient energy to cure the applied powder coatings. Due to the more rapid warming than may be achieved in conventional ovens, there are potential cost, time and energy savings from using eddy current curing. (In German) (WSCA Item Number 08/00326)

Section 69 Analytical Methods

KEUNE K & BOON J J Analytical imaging studies of cross-sections of paintings affected by lead soap aggregate formation. Studies Conservat. 2007, Vol 52 No 3, 161-76.
Paint cross-sections from five paintings affected by lead soaps were examined by the analytical imaging techniques of Fourier transform infrared spectroscopy, secondary ion mass spectroscopy and scanning electron microscopy combined with X-ray analysis. Interactions between the reactive components in paints forming lead soaps are discussed, as are multilayered paint systems with various lead-containing pigments, remineralisation inside lead soaps aggregates, and chloride inside lead soap aggregates. It is concluded that the various case studies demonstrate that one general scenario describing all aspects of the lead soap aggregates is unable to be given yet, the difficulty being that although formation of lead soaps is straightforward, the conditions under which this is happening are so multifaceted. 36 refs. (WSCA Item Number 08/00516)

Section 87 Legislation and Other Official Publications

ANON REACH (registration, evaluation and authorisation of chemicals): the basics. UK REACH Competent Authority Leaflet No 5, 2008, 4 pp. (Available at www.hse.gov.uk/reach/resources/basics.pdf).
The key stages in the REACH (registration, evaluation and authorisation of chemicals) process are described, considering preregistration, registration, evaluation, and authorisation. Reference is also made to restrictions, to classification and labelling, and to safety data sheets. (WSCA Item Number 08/00677)

For further information on WSCA please contact Dr Norman Morgan

Previous years: 2007 2006