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The color painting of ancient buildings has high historical and artistic value but is prone to aging due to long-term outdoor exposure. The purpose of this study is to develop a new type of sealing coating to mitigate the impact of ultraviolet (UV) light on color painting.

The new coating was subjected to a 500-h UV-aging test. Compared with the existing acrylic resin Primal AC33, the UV aging behavior of the new coating, such as color difference and gloss, was studied with aging time. The Fourier infrared spectra of the coatings were analyzed after the UV-aging test.

Compared with AC33, the antiaging performance of SF8 was substantially improved. SF8 has a lower color difference value and better light retention and hydrophobicity. The Fourier transform infrared spectroscopy results showed that the C-F bond and Si-O bonds in the resin of the optimized sealing coating protected the main chain C-C structure from degradation during the aging process; thus, the resin maintained good stability. The hindered amine light stabilizer TN292 added to the coating inhibited the antiaging process by trapping active free radicals.

To address the problem of UV aging of oil-decorated colored paintings, a new type of sealing coating with excellent antiaging properties was developed, laying the foundation for its demonstration application on the surface of ancient buildings.

Chemists at Cornell University have developed a series of monomolecular and polymeric precursors that photolyze to yield amine catalysts. These compounds could find use as additives in ultraviolet‐cured coatings and adhesives.

The purpose of this paper is to describe the ageing behaviour of acrylate‐based resins for stereolithography (SL) technology using different test methods and to investigate these effects on polymers.

Controlling the polymer degradation requires an understanding of many different phenomena, including the different chemical mechanisms underlying structural changes in polymer macromolecules, the influences of polymer morphology, the complexities of oxidation chemistry and the complex reaction pathways of polymer additives. Several ageing characterization experiments are given.

The paper covers the ageing process analysis of acrylate‐based polymers. An overview of the ageing behaviour is given, along with the bandwidth of material characteristics for a prolonged lifetime of this material class.

For research and development in the field of rapid prototyping (RP) materials data about ageing behaviour and environmental effects are crucial. The authors show possible methods for measuring these effects and discuss the consequences in material research using a recently developed biocompatible SL resin as an example.

The study of the ageing behaviour of polymers is important for understanding their usability, storage, lifetime and recycling. The presented polymeric formulations are able to meet the growing demand for both soft and stiff manufacturing resin materials in the engineering and medical fields.

The analysis of the ageing behaviour of polymer materials is an important issue for engineering applications, recycling of post‐consumer plastic waste, as well as the use of polymers as biological implants and matrices for drug delivery and the lifetime of an article. The paper gives an overview of details involving ageing behaviour and their meaning for applications of acrylate‐based SL resins and is therefore of high importance to people with interest in long‐term behaviour and ageing of RP materials.

The purpose of this paper is to study the resistance of wood-polypropylene and wood-wollastonite-polypropylene composites containing pigments to natural weathering.

Natural weathering of composites was conducted in Finnish climatic conditions for one year. The colour of the composites was determined with a spectrophotometer, the morphology of the composite surface was analysed by scanning electron microscopy (SEM), and the changes in the polymer structure in surface layer of the composites were analysed with differential scanning calorimetry (DSC). Charpy impact strength was determined with an impact tester.

The pigments used in this study reduced the colour change of the composites exposed to outdoor weathering as compared with the un-coloured composite. The carbon black pigment was more effective than the iron oxide pigment. Moreover, only the carbon black pigment was found to reduce the degradation of the surface layer of the composites. The addition of the carbon black pigment had a positive effect on the dimensional stability of the composites in a water absorption test. Only the combination of the carbon black pigment and wollastonite resulted in a composite which was capable to retain its Charpy impact strength both after one year of outdoor weathering and cyclic treatment.

This study is a part of continuous research on the development of wood-polymer composites (WPUs) suitable for outdoor applications in Finnish climatic conditions. The first part of the study, which has been published earlier, showed the results of weathering of composites in accelerated tests in comparison with 1,000 hours outdoor exposure during summer time (June and July). Outdoor weathering limited to 1,000 hours cannot give an objective view on the weathering behaviour of composites in Finnish climatic conditions. The results of the current study were obtained from one-year outdoor exposure of composites.

The wood-polypropylene composite made with the combination of the carbon black pigment and wollastonite can be recommended for outdoor applications. The study provides useful information on the resistance of wood-polypropylene composites to weathering in Finnish climatic conditions.

The purpose of this work was to study the effect of different wood surface preparations on the wetting and adhesion of coating.

In this research, six different chemical preparations to evaluate the photostability and properties of wood coating. Also, the effect of the same wood treatments on the properties of the coating, i.e. wetting, adhesion and the permeability of two types of coatings, was investigated.

As a result, benzoyl chloride and chromic acid were found to be the most effective photostabilizing preparations. Solvent-based polyurethane was more compatible with the prepared wood surfaces compared with water-based alkyd coatings.

Chemical modifications of wood surfaces affected the wetting of various coatings.

Various surface properties could be changed using preparation that affects important coating properties.

Unfortunately, the properties of transparent wood coatings used outdoors disappear through the early years of use, essentially due to the wood substrate’s photodegradation.

Wood is a widespread substrate because of its comfortable handling, availability, proper cost of preparation and its good mechanical strength because of its density. Architects and designers tend to use wood in the construction of green buildings. However, this material is disposed to weathering while using outdoors and it should be solved.

Making Fine Powders ‐ Extremely fine and uniform particles, of 5–50 nanometers, have been produced by a process being developed at Battelle Pacific Northwest Laboratories. Researchers have used the technique to synthesize new, highly dispersed catalysts with a high surface area. It offers a way to make other products which have improved properties: ceramic ball bearings and gears which are stronger and more durable than those available today, and pigments for paints and inks.

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.

The degradation of coatings is, of course, a major area of interest for paint chemists. One of the coatings that degrades, much to the consumer's despair, is automotive coatings. The degradation of an acrylic‐melamine, cross‐linked coating containing finely dispersed pigment, metallic flake, and other additives was studied by English and Spinelli (Organic Coatings and Applied Polymer Science Proceedings, preprints of papers presented by the Division of Organic Coatings and Plastics Chemistry at the American Chemical Society, 185th National Meeting, Seattle, Washington, March 20–25, 1983, p. 733) using diffuse reflectance infra‐red spectroscopy. They found that the degradation is facilitated near the surface by ultra‐violet light and that there is a cleavage of the nitrogen‐carbon bond on the methoxymethylamino moities. Much of the degradation appears to take place at the surface level and degradation of bonds does not lead to significant self‐condensation of the degraded materials. The authors indicate that they are currently using MMR techniques to identify the products of degradation.