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Photochromic surface coating on textiles may create new fashion opportunities. It also enhances the ultraviolet (UV) protection ability of the coated products. In this study, a spirooxazine dye and a silane that bears a long alkyl chain have been used to produce hybrid photochromic silica coatings on wool fabrics. Four stabilisers are added separately to the photochromic silica coatings to examine their influence on photostability and photochromic behaviour. It is found that the addition of UV stabilisers slightly reduces the photochromic response speed and photochromic absorption. However, the addition of UV stabilisers to the photochromic coating considerably improves the photochromic lifetime. Among the four UV stabilisers studied, the quencher results in the best improvement to photostability with the lowest reduction in photochromic absorption.

The purpose of this paper is to study natural and accelerated weathering of wood-polypropylene (WF-PP) and wood-wollastonite-polypropylene composites made with and without carbon black.

Natural weathering was conducted in Ruokolahti, Finland in the time of year when solar radiation was maximal. The accelerated weathering tests included exposure to a xenon-arc source with and without spray, and a cyclic test consisting of water immersion–freeze–thaw stages.

Both the type of weathering and the formulation of the composite determined the degree of change in their properties. Weathering, including xenon-arc exposure with spray resulted in much higher changes of colour of non-pigmented composites compared to natural weathering or xenon-arc weathering without spray. Both UV irradiation and moisture had an adverse effect on the Charpy impact strength of non-pigmented composites. Carbon black containing composites performed better than non-pigmented composites.

This study is a part of an ongoing research on the development of wood-polymer composites (WPCs) suitable for outdoor applications in Finnish climatic conditions. Outdoor weathering limited to 1,000 h cannot be used for the prediction of the service life of composites and was used here solely for comparative purposes.

This paper will help to understand the effect of different weathering factors on the behaviour of WF-PP and wood-wollastonite-polypropylene composites made with and without carbon black (as UV stabiliser). The study demonstrated that while accelerated weathering tests provided useful information on the resistance of WF-PP composites to different weathering factors, they cannot be used alone to predict the behaviour of WPCs meant for outdoor application.

The total utilisable resources of carbon in the biosphere are enormous by any standards. In the atmosphere alone there are about 700 billion tons of carbon as carbon dioxide and in the oceans there are stored 35,000 billion tons of available carbon dioxide. These two reserves alone amount to about four times the estimated total reserves of carbon in the form of coal and oil. The essential difference between these alternative sources of carbon is that whereas the carbon in the biological cycle is being continuously circulated in a system in which the total amount of carbon remains sensibly constant (there is a further 30,000 billion tons of carbon in the form of biological organic matter), the carbon in the form of coal and oil reserves are being rapidly depleted with consequent escalating cost and the lifetime of this source of chemicals and energy is variously estimated as being between 20 and 50 years.

Officers and Council of the British Colour Makers Association for the year 1979/80 will be:— Chairman; Mr. M. A. Kerr, Ciba‐Geigy (P&A) Co. Pigments Division. Vice‐Chairman; Mr. G. R. Streatfield, Blythe Colours Ltd. Honorary Treasurer; Mr. F. B. Mortimer‐Ford, Horace Cory & Co. Ltd. Members: Mr. W. B. Cork, Reckitts Colours Ltd. Mr. A. R. Dauwe, Imperial Chemical Industries Ltd. Dr. M. Hill, Manox Ltd. Mr. B. R. Howe, Burrell Colours Ltd. Mr. E. H. Leadbeater, E. P. Bray & Co. Ltd. Mr. A. Pearce, Williams (Hounslow) Ltd. Mr. P. Perkin, Ellis Jones & Co. (Stock‐port) Ltd. Secretary; Mr. A. G. Wyatt.

The results of research conducted into air‐dried terpolymer films shows the effect of various factors on degradation under accelerated weathering conditions

Now being marketed in the UK by Cetema Ltd are the Nafturan 2000 series of potting resins for protecting electrical and electronic components against humidity. The Nafturan 2000 products are solvent‐free two‐component resins based on polyurethane elastomer. They can be cured at room temperature to give a flexible and reliable protective barrier resin which is completely resistant to humidity.

Coatings are subject to photoaging during their lifetime. Ultraviolet radiations absorbing additives (UVAs) and hindered amine light stabilisers (HALS) often are added to improve their performance. To improve performance of coatings, it is important to use optimum quantity of such additives.

In this study, hydroxyl‐terminated polyester was synthesised and then crosslinked using isophoronediisocyanate. These clear coats were then stabilised with various additives such as Tinuvin 1130, 123 and 292. The synergistic effect of these additives was also studied. The optical properties of coatings such as yellowness, whiteness and gloss of coatings were studied after exposing these coatings to various environments such as QUV weathering, direct UV and xenon arc.

The results showed that the coatings stabilised with combination of additives performed better than the unstabilised coatings as well as single additive coatings. A synergism was observed when using a combination of the UVAs and HALS.

The additives used were found to be compatible with the binder systems under study and was not found to be universally compatible with all resins.

UV degradation is a major concern in coatings both aesthetically and functionally. This study aimed at optimising the concentrations of UV stabilisers in order to increase the effective life time of exterior coatings.

UV stabilisers are routinely used in coatings for exterior applications. However, our aim was to optimise the concentrations of these additives in the coating so as to reduce the cost while keeping the performance of the coatings unaffected. By studying the synergy of the additives, we have also optimised their concentrations to further increase the life of the coatings.

Surfex '88 is the first UK exhibition with the new Akzo Corporate Identity to operate in a more market orientated structure. Within the chemical division of Akzo a group has been formed to promote the wide range of Akzo chemicals for coatings applications. Among the products that can be discussed will be:

The purpose of this paper is to study the effect of acrylated guar gum (GG) compared with GG in acrylic emulsions with reference to its viscosity, film properties such as mechanical strength, weathering properties and clarity.

The acrylate derivatives were synthesised and characterised and then incorporated in acrylic emulsions and their rheology studied. Films were analysed for their clarity and mechanical properties. The films were then subjected to UV radiation and the influence of these additives on the weathering properties was studied.

The viscosity of acrylated GGs in emulsions was lower than that of GG in emulsion because of the increased hydrophobic nature and hence reduced water‐binding capacity. The mechanical properties of acrylated GGs were superior compared with GG due to increased compatibility of the additive with the polymer binder. This was further confirmed with increased clarity of the films. Acrylated GG was found to act as a protective additive with reference to UV degradation of the coatings.

The performance of these additives was analysed on un‐pigmented coating formulations, which may not conform with pigmented coatings.

These biodegradable additives synthesised from renewable resources could be used to increase the mechanical strength as UV stabilisers and in some cases also as rheology modifiers.

The use of acrylated polysaccharides to increase mechanical and weathering properties allows the use of biodegradable, renewable resources as opposed to petroleum‐based compounds.