Resin corrosion resistance, flexibility and good manufacturability

The resin is obtained by modifying epoxy vinyl ester resin with urethane (such as TDI), and has both intrachain unsaturation and chain end unsaturation. Compared with the usual bisphenol A epoxy vinyl ester resin, it has excellent corrosion resistance, flexibility and good processability. Due to the introduction of urethane, the compatibility of the resin with the fiber is improved, and it can maintain Good air-drying properties on the resin surface. Can be suitable for various processes such as winding.

As a category of unsaturated polyester resin, vinyl ester resin has higher activity and faster curing reaction speed, resulting in a larger curing shrinkage rate after curing of vinyl ester resin. Generally, unsaturated polyester resin (including conventional vinyl resin) ) The shrinkage during curing is relatively large, and the volume shrinkage can reach about 7-10%. With the improvement of technical requirements for high-performance resins at home and abroad, it is hoped to find some vinyl ester resins with low curing shrinkage. This is an early 21st century. A technological breakthrough point that many domestic and foreign manufacturers are striving to seek. The mechanism of low-shrinkage resin is more complicated, and some manufacturers used the method of adding low-shrinkage additive (LPA) in order to overcome the curing shrinkage of the resin to achieve the goal, but there are limitations in its application, and more manufacturers are trying to pass the resin Synthetic methods and molecular design levels to solve this technical problem,

Ultra-low shrinkage epoxy vinyl ester resin can better meet the requirements of high-quality FRP products with its unique properties of sufficient mechanical strength and rigidity, sufficient dimensional stability, thermal cycle resistance, and corrosion resistance.

As a high-performance unsaturated resin, the thickening properties of vinyl resins have always been the research direction of various manufacturers. This is because the unique application characteristics of BMC/SMC have been recognized by customers, especially with the application of BMC/SMC in automotive zero. For component applications, thickened vinyl resins can withstand higher impact forces than general-purpose unsaturated resins, and have good creep and fatigue resistance. These components include wheels, seats, radiator frames, grille panels, engine valve covers, and more. Of course, thickened vinyl resins can be widely used in electrical insulation, the production of industrial pump valves, golf heads, and the like.

As a thickening vinyl resin, the resin is naturally required to have the following characteristics: ① good wettability with reinforcing materials and fillers; ② low initial viscosity and rapid thickening characteristics; ③ good mechanical properties, including toughness and resistance Fatigue characteristics, etc.; ④ Longer storage period; ⑤ Lower curing exothermic peak and lower styrene volatilization, etc. In order to achieve the effect of use, in the synthesis research of vinyl resin, the original more common method is to introduce an acidic functional group (carboxylic acid) on the vinyl ester molecule, and then use these carboxyl groups and alkaline earth metal oxides (such as magnesium oxide, oxide Calcium, etc.), but this method takes a long time to thicken, generally takes several days, and is sensitive to water content. Therefore, another method has also been developed, that is to use polyisocyanates and polyols to react to generate a network structure, so as to achieve rapid thickening of the resin. This method can be suitable for low pressure molding, with stable viscosity control, temperature resistance It has the characteristics of low humidity requirement and long storage period, and at the same time, the product has the characteristics of high interlayer bonding strength. At the same time, low acid value resin with excess alcohol can be used as thickener.