Epoxy soybean oil acrylate_Kain Industrial Additive

Preparation of epoxy soybean oil acrylate

Preparation of epoxy soybean oil acrylate photosensitive coating by half-ester modification method

Epoxy soybean oil acrylate coatings are emerging

Epoxy soybean oil acrylate is a photoactive prepolymer with low viscosity, little skin irritation and excellent pigment wettability. It is obtained from the esterification reaction of acrylic acid and epoxy soybean oil. The essence of the reaction is the addition reaction of carboxylic acid and epoxy group. Commonly used catalysts in the reaction include: N-N dimethylaniline, N-N dimethylbenzylamine, triethylamine, 1,4-diazabicyclo[2.2.2]-octane, triphenylphosphine, etc. Due to the long molecular chain and low cross-linking density of epoxy soybean oil acrylate, it can significantly improve the toughness and adhesion of the coating, and the main raw material for its synthesis, epoxidized soybean oil, is cheap and rich in resources.

UV light-curable coatings have attracted much attention due to their advantages such as fast curing speed, high production efficiency, and stable product performance. They are one of the fastest growing varieties in the coating industry today. In recent years, UV-curable coatings have not only gradually replaced traditional coatings for wood and metal, but also continuously opened up new application areas, such as packaging of electronic components, coloring of optical fibers, varnishing of leather, and coating and bonding of chemical fibers. etc., the development prospects are very broad.

Preparation of epoxy soybean oil acrylate

In a four-necked flask equipped with a reflux condenser, a stirrer, a dropping funnel, and a thermometer, add a certain amount of epoxidized soybean oil. When the oil bath is heated to 85°C, add triphenylphosphine containing the catalyst dropwise in proportion. , a mixed solution of polymerization inhibitor hydroquinone and acrylic acid, control the dropping speed and increase the temperature of the oil bath while adding. After the mixed solution is added dropwise, ensure that the oil temperature rises to 110°C. At this time, remove the dropping funnel and insert a thermometer to maintain a constant temperature reaction of the materials in the bottle at 110°C until the acid value of the system reaches 5 mgKOH/g.

Preparation of epoxy soybean oil acrylate photosensitive coating by half-ester modification method

The addition reaction of maleic anhydride and hydroxyethyl acrylate produces an adduct with a carboxyl group at one end and an acrylate group at the other end. This half-ester molecule is then reacted with epoxy soybean oil to synthesize epoxy soybean oil acrylate photosensitive preform Polymer. Since this half-ester molecule contains twice as many unsaturated double bonds as acrylic acid, and is easy to undergo a ring-opening reaction with epoxides, the epoxy soybean oil acrylate photosensitive coating synthesized by this method is better than directly reacting epoxy soybean oil with acrylic acid. The photosensitive coating prepared by the esterification reaction has a short photocuring time, can be completely cured in 35 seconds, and has strong photosensitivity. Since its photosensitive prepolymer has an aliphatic chain structure, its adhesion and flexibility are better than bisphenol A-type rings. Oxygen resin photosensitive coatings have great development value. At the same time, epoxy soybean oil acrylate is a photoactive oligomer with low viscosity, low irritation, and excellent pigment wettability. It is widely used in UV-curable paints. Recently, researchers have prepared colored epoxy soybean oil acrylate paint. , and found that this system has good photosensitivity and can be used for UV curing.

Epoxy soybean oil acrylate coatings are emerging

Low-cost, environmentally friendly epoxy soybean oil has become a research hotspot in the field of coatings at home and abroad in recent years. Among them, UV (light-curing) free radical curing epoxy soybean oil acrylate coatings have achieved good results. Domestic research on Epoxy soybean oil acrylate and modified epoxy soybean oil acrylate have been extensively studied in the application of UV-curable optical fiber inner coatings. According to experts from the China Epoxy Resin Industry Association, its applications are also emerging in some fields, especially as surface metallized film coatings, which are of great significance and are suitable for manufacturing cardboard varnishes, varnishes, wood varnishes, pigments, etc. The application of epoxy soybean oil acrylate coatings can be described as "emerging". Epoxy soybean oil acrylate is obtained by the esterification reaction of acrylic acid and epoxy soybean oil. The essence of the reaction is the addition reaction of carboxylic acid and epoxy group. Commonly used catalysts in the reaction include: N-N dimethylaniline, N-N dimethylbenzylamine, triethylamine, 1,4-diazabicyclo[2.2.2]-octane, triphenylphosphine, etc. Due to its long molecular chain and low cross-linking density, epoxy soybean oil acrylate can significantly improve the toughness and adhesion of the coating.

Taking into account factors such as the cheaper price of epoxy soybean oil, epoxy soybean oil acrylate-based photosensitive coatings have broad development prospects. According to experts from the China Epoxy Resin Industry Association, research on epoxy soybean oil acrylate coatings is very active at home and abroad, and UCB Company in the United States has already carried out commercial production, such as Ebecry 860. The general methods used to synthesize epoxy soybean oil acrylate are: direct esterification reaction of epoxy soybean oil and acrylic acid, or the use of half-ester modification method. The former is currently commonly used. UV radical light-cured epoxy acrylate coatings mainly use bisphenol A and phenolic epoxy. The disadvantages are that the cured film is insufficiently flexible and highly brittle; epoxy soybean oil acrylate can make up for this shortcoming. Domestic Anhui Polytechnic University used the first synthesis method to conduct in-depth research on this system and discussed the synthesis process of epoxy soybean oil acrylate. The experiment found that a slight excess of epoxy soybean oil is beneficial to the conversion of acrylic acid. After determining n (epoxy group): The optimal reaction conditions were determined through orthogonal experimental analysis based on n(acid)=1.12. On this basis, the above system is modified with marmicic anhydride, a hydrophilic carboxyl group is introduced into the epoxy acrylate molecule, and finally neutralized with amine or ammonia to prepareWater-based photosensitive epoxy acrylate prepolymer.

The addition of maleic anhydride increases the density of double bonds and increases the cross-linking density of the cross-linked product, thereby increasing the curing speed and the hardness of the cured film. In addition, considering the high molecular rigidity of bisphenol A epoxy acrylate, the cured film formed has high strength, fast curing speed, and high viscosity, while epoxy soybean oil acrylate has low viscosity, is cheap, and has strong adhesion, but has a slow assimilation speed. , the cured film has the characteristics of low hardness. Epoxy soybean oil and bisphenol A epoxy resin are mixed in a certain ratio to prepare epoxy acrylate, which not only solves the problem of high viscosity during synthesis, but also improves the overall performance of the cured film. Experts from the China Epoxy Resin Industry Association said that epoxy soybean oil acrylate oligomer was also synthesized in China, and the system was cured with ultraviolet light. The effect of SiO2 matting agent (UV55C) on the coating properties was studied: The test showed that UV55C The optimal dosage is about 5%. Since the matting agent particles have small particle size, large specific surface area, and high surface activity, its addition not only improves the hardness, wear resistance and adhesion of the coating film, but also improves the curing rate. And the glossiness of the coating film has decreased, which has certain economic significance.

Reference information: www.epoxy-e.cn