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In addition to asbestos, numerous other materials of interest to the paint industry have been subjected to toxicological inquiry. Thus, glycidyl ethers, representative of which are epoxy resins and reactive diluents and plasticizers such as phenyl glycidyl ether or butyl glycidyl ether may be health hazards according to the National Institute for Occupational Safety and Health. This has been pointed out in an article in Modern Paint & Coatings [69,3 (1979) p. 66].

Epoxy resins are compounds which contain in their molecule more than one 1,2 epoxy group capable of undergoing polyreactions, referred to as curing reactions. The presence of epoxy groups may be either internal, terminal or on cyclic structures. Polyreactions take place at varying temperatures from low room temperature cure to high temperature cure systems upon addition of curing agents such as amines, amides or carboxylic acid anhydrides. The uncured resins which range from low viscosity liquids to high melting solids, soluble in organic solvents, become insoluble, infusible hard materials on curing due to crosslinked structure of the cured products.

The purpose of this study is the development of sustainable and low-formaldehyde emission wood adhesive formulations.

Three-step urea formaldehyde (UF) resin has been in situ modified with calcium lignosulfonate (LS) and/or 1,4 butanediol diglycidyl ether (GE). The structural, chemical, thermal and morphological characterizations were carried out on resin samples. These resins have been applied for particleboard pressing, and UF, UF-LS and UF-GE were evaluated as P2 classes according to EN 312.

The results show that the improved LS- or diglycidyl ether-modified UF wood adhesives were successful in their adhesive capacity, and the formaldehyde content of the final product was obtained as low as 8 mg/100 g. This paper highlights that the presented adhesive formulations could be a potential eco-friendly and cost-effective alternative to formaldehyde-based wood adhesives for interior particleboard production.

Combination of LS and GE resulted in weaker mechanical properties and fulfilled P1 class particleboards due to temperature and duration conditions. Therefore, in situ usage of LS or GE in UF resins is highly recommended for particleboard pressing. Formaldehyde content of particleboards was determined with the perforator method according to EN 12460-5 and all of the particleboards exhibited E1 class. LS was more efficient in decreasing formaldehyde content than GE.

This study provides the application of particleboards with low formaldehyde emission.

The developed LS- and diglycidyl ether-modified UF resins made it possible to obtain boards with significantly low formaldehyde content compared with commercial resins.

The developed formaldehyde-based resin formulation made it possible to produce laboratory-scale board prototypes using LS or GE without sacrificing of press factors and panel quality.

The purpose of this paper is to develop a flexible, as well as a rigid, polyurethane (PU) product using polyols derived from renewable resource for suitable application.

Cardanol is converted into corresponding glycidyl ether by reacting it with epichlorohydrin. The resulting glycidyl ether is hydrolysed to the corresponding diol in the presence of a heteropolyacid, which acted as a catalyst. The diol obtained is used for synthesising PU's by reacting it with various mole ratios of toluene diisocyanate (TDI) and isophorone diisocyanate (IPDI) and their physicomechanical, chemical and morphological properties are studied.

The polyol selected for the present paper has unique structural characteristics such as C15 chain length, which contributes to flexibility, and an aromatic ring, which imparts rigidity in the final application of resulting PU. By choosing optimum ratio of NCO/OH, it is possible to obtain a system, which can be used for the development of a flexible as well as a rigid polymer for suitable application.

The cardanol and dodecatungstosilic acid used are of a particular grade and of a particular manufacturer. Furthermore, it could be obtained from different sources and of different grades. The spectral studies done are purely qualitative. Gloss is tested for the samples at 600, whereas other angles can also be used.

The method developed provided a simple and practical solution to improve performance characteristics of PU resins, which also proves to be cost effective.

The PU product developed due to its enhanced coating properties can be used in various surface‐coating applications.

Epoxy resins have probably provided more interesting chemistry than any other polymer the paint industry uses. In this category of interesting chemistry is Russian work [World Surface Coatings Abstracts (1978) Abstract No. 1558] which describes the preparation of structurally coloured epoxy resins — i.e. of epoxy resins which are inherently coloured. The work involves condensing bisphenol A and epichlorohydrin in the presence of small amounts (0.1 to 0.5 weight per cent) of a coloured co‐monomer dye. The dye, for example, can be the glycidyl ether of alpha aminoanthroquinone. Coloured products resulted which presumably would provide coatings with intrinsic colour. Of course, this colour could be modified by extrinsic dyes and pigments. The concept of producing coloured polymers is not a new one. One approach to making black polyethylene for black film is to carry out the polymerisation of the ethylene in a fluid bed of carbon particles. The carbon particles presumably serve as a nucleus around which the polymer forms and at the same time serves to impart a black colour to the polymer particle. This technology has never been commercialised but it is certainly of interest to the paint chemist for it presents a new concept in carrying out a major objective of the paint industry — namely, to impart colour to solutions of polymers.

During recent years, various hydantoin based heterocyclic glycidyl amine resins have been developed. In these resins the presence of nitrogen containing heterocycle provides extensive variation in polarity, viscosity and hydrophobicity by the choice of alkyl groups. Most of these resins have low viscosity, high polarity and long pot life ensuring easy wetting and good adhesion. These resins can provide useful properties for casting, fibrous reinforcement, adhesives and coatings. In the present work, two resins, 1‐glycidyl‐ 3‐glycidyloxymethyl‐5, 5‐dimethylhydantoin and 1‐glycidyl‐3‐(2‐glycidyloxybutyl)‐5, 5‐dimethylhydantoin have been prepared using 5, 5‐dimethylhydantoin as the starting raw material. The resins have also been characterised for their various physical and chemical properties.

The flammability of epoxy resin is a major disadvantage in applications that require flame resistance. Epoxy monomers and hardeners containing flame-retardant elements are molecularly incorporated in the resin network are expected to exhibit better flame resistance than those borne on an additive approach. In recent years, because of health and environmental regulation, the use of waterborne coatings has received many attentions. However, waterborne epoxy resin curing agent with excellent flame retardancy has been seldom reported. The paper aims to study the preparation of waterborne P-N-containing epoxy resin curing agent and its performances (P-N – phosphorous and nitrogen).

Waterborne P-N-containing epoxy curing agent was prepared in this study using reactive flame retardant 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-xa-10-phosphaphenanthrene-10-oxide, liquid epoxy resin, triethylenetetramine and butyl glycidyl ether at the mole ratio of 1.0:2.0:2.0:2.0.

The results show that the epoxy thermoset from the prepared P-N-containing curing agent presents good flame retardancy and can pass the V-1 rating, and the cured epoxy thermoset film presents excellent performances such as water resistance, adhesion, impact resistance and pencil hardness. This study provides useful suggestions for the application of the water-borne flame retardancy epoxy resins in coating industry.

Each step of products during the preparation of waterborne P-N-containing epoxy curing agent cannot be accurately tested.

This method for synthesis of waterborne P-N-containing epoxy curing agent is novel and could be used for various applications in epoxy coating industry.

Oleochemicals are materials not derived from petroleum, but from the main chemical components of animal, marine and vegetable oils, glycerides, and include the fatty acids themselves and glycerol, and many derivatives, e.g. fatty alcohols, fatty amides, fatty amines, fatty acid esters, sulphur derivatives, phosphorous derivatives, polyoxyethylated and polyoxypropylated materials, etc.

Behind every successful technology is a great body of scientific knowledge. The paint industry managed to get along pretty well from the time of the Egyptians until World War I, a span of approximately 5,000 years, without much scientific insight. Indeed, the empirical approach to paint formulation could hardly be criticised. When one visits museums of Egyptology today, one sees coatings formulated three to five thousand years ago which are bright coloured and which still have good adhesion and film integrity. But coating mummy cases in a very dry climate is considerably less demanding than coating missiles which find themselves in a hostile environment. Although paint for mummy cases, houses, and barns and even the first assembly‐line‐produced automobiles could be made without much scientific understanding, it is fair to say that coatings for the exacting demands of modern technology could never have evolved without an understanding of the scientific principles on which the modern coatings industry is based. The scientific basis for the modern coatings industry is found in an understanding of polymer chemistry, an understanding of the chemistry of solvents, a knowledge of the chemistry of pigments, and a large body of physical chemistry relating to solubility, rheology, adhesion, cohesion, and many other important phenomena.

Acrylic resins are formulated into protective coatings in several ways. Most important volumewise are waterborne formulations based either on pure acrylics or on acrylic‐vinyl copolymers. Second most important are solvent‐based enamels and lacquers widely used for product finishes particularly in the automotive and appliance industries. An innovation of a decade or so ago is proving popular in this area, namely two component coatings based on hydroxyl‐containing acrylics and di‐ or polyisocyanates. These combine many of the good features of acrylics and urethanes and provide hard thermoset coatings. Yet they cure at temperatures as low as ambient.