The latest high-efficiency epoxy curing accelerato

2022-09-21
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The new high-efficiency epoxy curing accelerator has good toughening effect

the new high-efficiency epoxy curing accelerator has good toughening effect

May 14, 2004

the new high-efficiency epoxy resin curing accelerator that can change the purity improvement of the epoxy resin produced by high-purity bisphenol A, the curing system that appears in the application, and the long gel time has made new achievements

with the requirements of environmental protection and the improvement of the quality of electronic and electrical products, bisphenol, the raw material used in the production of epoxy resin, is easy to realize the scope of industrial production. The production process of a has long been replaced by the ion exchange resin method with the backward sulfuric acid method and hydrogen chloride method, and even Bluestar new material Wuxi resin factory () has produced carbon grade products. The cycloepoxy resin produced by bisphenol A with high purity, light color, high purity, and only a very small amount of impurities, such as recent isomers, free phenols, allyl phenols, also has some problems in application, such as the epoxy resin anhydride curing system has a long gel time, high curing temperature, and long curing time. The above defects exist when the epoxy resin tung oil anhydride (TOA) curing system is used to bond the mica insulating tape of large motors, or when preparing less (no) solvent epoxy paint. Therefore, some users feel that using "refined" bisphenol A also has "inconvenience", which is mainly manifested in long gel time, high brittleness, poor toughness, poor adhesion, etc., resulting in easy cracking of products and reduced qualification rate

experts pointed out that the reason is that "crude" bisphenol A contains a large amount of free phenols, isomers, sulfonic acids and other unknown impurities, which can promote and toughen the curing of epoxy resin anhydride curing system. This new high-efficiency epoxy resin curing accelerator is applied to the curing system of refined bisphenol A epoxy resin tung oil anhydride, which can shorten the gel time from 20 ~ 30min (200 ℃) to 3 ~ 5min (200 ℃), and the curing process is stable. It has the effect of increasing the toughness of more than 300000 patients with chronic renal failure receiving dialysis treatment in Japan alone

the commonly used accelerators of epoxy resin anhydride curing system include tertiary amines, quaternary ammonium salts, nitrogen heterocyclic compounds, etc. Such as DMP-30 (k-54), n.n-dimethylbenzylamine, m-phenyldimethylamine, imidazoles, pyridines, alcohol amines, etc. In order to overcome the defects of the cured resin, such as large internal stress, poor toughness and poor impact resistance, it is necessary to add an active toughening agent to overcome this defect. The substances suitable for active toughening agent of epoxy resin mainly include epoxy ester (such as epoxy soybean oil, stearic acid epoxy ester, etc.), synthetic rubber (such as liquid polysulfide rubber, CTBN, ATBN, etc.), polyamide resin (such as low molecular weight liquid polyamide, etc.), polyester resin (such as various polyesters, unsaturated polyester, etc.), anhydride polymer (such as polydecanoic anhydride, polynonionic anhydride, etc.), polyurethane, silicone modifier, etc

considering the processability, miscibility, stability and the toughening effect of the resin cured product, researchers choose polyether substances as the toughening component in the accelerator formula. The molecular structure contains hydroxyl groups, which can be ring opened and polymerized with epoxy groups at high temperature. Because the molecular chain is a flexible chain structure, it can significantly reduce the brittleness of the resin cured product, improve the impact strength and elongation, and reduce the curing shrinkage, Reduce the internal stress of the cured resin

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