Low cost, environment friendly epoxy soybean oil, in recent years has become a research hotspot in the field of coatings at home and abroad, including UV light (curing) radical curing epoxy soybean oil acrylate coatings obtained good results, domestic modified epoxy soybean oil for epoxy soybean oil acrylate and acrylic ester, in the application of uv-curing optical fiber lining coating has a more in-depth research.
According to China epoxy resin industry association experts, its application has arisen in some areas, especially for surface metallization film coating meaning is very big, suitable for manufacturing cardboard varnish, hood light paint, wood varnish, paint, etc. Epoxidized soybean oil acrylate coating, it may be said "scene". Epoxy soybean oil acrylate from acrylic acid and epoxy soybean oil esterification reaction, reaction essence is the epoxy groups and carboxylic acid addition reaction. That is commonly used in reaction catalyst are: N - N, N - dimethyl aniline N dimethyl benzyl amine, triethylamine, 1, 4 - dinitrogen mixed double loop [2.2.2] - octane, triphenylphosphine, etc. Because of the epoxy soybean oil acrylate molecular chain is longer, the crosslink density is small, can significantly improve the toughness of the coating and adhesive force.
Considering the factors such as epoxy soybean oil prices cheaper, the light sensitivity of epoxy soybean oil acrylate based coating has a broad development prospects. According to China epoxy resin industry association experts, domestic and foreign studies of epoxy soybean oil acrylate coating was active, UCB company in the United States have carried on the commercial production, such as Ebecry 860. The synthesis of epoxy soybean oil acrylate generally adopt the method are: the epoxy soybean oil directly with acrylic acid on the esterification reaction, the method is to use a half ester modified method is that the former is generally used at present. Free radical UV light curing epoxy acrylate coating mainly using bisphenol A type and type phenolic epoxy, the disadvantage is that its curing film flexibility deficiency, high brittleness; The epoxy soybean oil acrylate, can make up for the defect of domestic anhui university of science and technology, the first form of synthesis method carried on the thorough research to this system, discusses the synthesis process of epoxy soybean oil acrylate, it was found that the conversion of epoxy soybean oil is a bit too much for acrylic, in determining the n (epoxy) : n (acid) = 1.12 on the basis of the analysis of the optimum reaction conditions were determined by orthogonal experiments. On the basis of using mami anhydride to modification of the system, the introduction of hydrophilic groups in the epoxy acrylate molecular carboxylic, with amine and ammonia neutralization was finally water-based photosensitive epoxy acrylates prepolymer.
Because of the addition of maleic anhydride increased the density of a double bond, increase the crosslinking density of the crosslinked product, so as to improve the hardness of the curing speed and cured film. In addition, considering the bisphenol A epoxy acrylate molecular big rigidity, curing film formation of high strength, curing speed, high viscosity, and the epoxy soybean oil acrylate viscosity is small, cheap, strong adhesion, but slow assimilation, curing film hardness is small, the characteristics of the epoxy soybean oil and bisphenol A epoxy resin according to certain proportion of mixed preparation of epoxy acrylate, already solved the problem of the composite viscosity big, and improved the curing film comprehensive performance. China epoxy resin industry association experts said that domestic epoxy soybean oil acrylate oligomer was synthesized, and the system USES the uv-curable, studied the SiO2 matting agent (UV55C) effect on the properties of coating: test showed that the best dosage of UV55C is about 5%, due to the matting agent particles with small size, large specific surface area and high surface activity, its join in improving the coating hardness, abrasion resistance and adhesion at the same time also makes the curing rate and coating glossiness, has certain economic significance.
Half ester modified method is also used for the preparation of epoxy soybean oil acrylate type photosensitive coating. According to China epoxy resin industry association experts, such as maleic anhydride and acrylic hydroxyl ethyl ester addition reaction generates end carboxyl, acrylic ester base at one end of the adduct, this half ester molecule reacts with the epoxy soybean oil synthesis of epoxy soybean oil acrylate photosensitive prepolymer. Because of this half ester molecule containing unsaturated double bond more than double the amount of acrylic, and easy for ring opening reaction with epoxide, therefore the synthesis of epoxy soybean oil acrylate photosensitive coating than directly to the preparation of epoxy soybean oil and acrylic acid on the esterification reaction of photosensitive coating light curing time is short, 35 seconds can be completely cured, photosensitive sex is stronger, and due to its photosensitive prepolymer as fat chain structure, adhesion and flexibility is better than that of bisphenol A type epoxy resin photosensitive coating, has A great development value. At the same time the epoxy soybean oil acrylate is a low viscosity, low irritation, light active oligomer of excellent pigment wetting, widely used in uv-curing paint, recently have researchers were coloured epoxy soybean oil acrylate coatings, and found that this system has good light sensitivity, can be used for uv curing.
