The research and development of organophosphorus compounds is rapidly developing from a chain structure to a ring structure, in which the phosphonium compound, DOPO and its derivatives, have a unique molecular structure (biphenyl ring and phenanthrene ring structure coexist), and It has received a lot of excellent performance and has received much attention. According to experts, since the first successful synthesis of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) by Saito et al in the 1970s, the development and application of DOPO derivatives have changed. It is becoming more and more active. One of the research hotspots is to introduce a new DOPO derivative in the epoxy resin instead of the bromine compound to achieve the purpose of halogen-free flame retardant. Experts say that the result is a flame retardant cleaning epoxy.
In this respect, research and development are mainly concentrated in two directions: one is to use DOPO derivatives as reactive flame retardants, introduced into the ring resin matrix structure, and then cured to obtain phosphorus-containing epoxy resin; the second is to cure with DOPO derivatives. The agent cures the ordinary epoxy resin to form a phosphorus-containing epoxy resin. In this paper, the new varieties of epoxy resin flame retardants and curing agents used in domestic and foreign DOPO derivatives and the flame retardancy and thermal properties are reviewed. In the development and application of flame retardants, DOPO(I) was reacted with itaconic acid, maleic acid and benzoquinone respectively to obtain three kinds of DOPO derivatives II, III and IV, and I-IV was reacted with epoxy resin to obtain high. Performance epoxy resin, cured product with high Tg, Td and high modulus of elasticity and good flame retardancy, suitable for printed circuit boards and semiconductor packages. U.S. Patent] proposes a new type of flame retardant V, which is formed by the reaction of DOPO with naphthoquinone. This phosphorus-containing epoxy resin exhibits higher curing than tetrabromobisphenol A (TBBA) type cured epoxy resin. Thermal stability and carbonization rate.
In the development of curing agents, DOPO polyphenolic hydroxyl or polyamino derivatives can be used as curing agents for polymers. The properties of epoxy resins cured by them are quite different from those of brominated epoxy resins. Especially in terms of flame retardancy and thermal stability, the difference is obvious. Recent studies have shown that modified phenolic resins formed by introducing DOPO into phenolic resins are more suitable for use as curing agents. There are also two reported modified phenolic resins X and XI which are also useful as curing agents for CNE resins. The product exhibited good thermal stability (>320 ° C), high Tg (159-178 ° C), high char formation rate (N2, 70 ° C, >50%) and LOI value (26-32.5). Compared with DOPO derivative III, these modified phenolic resins have similar properties, but because the modified phenolic resin has better compatibility with the polymer, the process is relatively simple and the cost is lower, so that it can be better promoted. Applications, both of which are useful as curing agents for epoxy resins in semiconductor packages and electronic laminates.
The introduction of DOPO derivatives as flame retardants and curing agents into epoxy resins improves the flame retardancy and thermal stability of epoxy resins, and more importantly, avoids the use of brominated epoxy resins in the process of use and recycling. The pollution caused has opened up a new path for the development of epoxy resin. Experts believe that the development and application of DOPO derivatives in the future will need to solve two or two problems: simplifying the process from DOPO synthesis, reducing costs, laying a solid foundation for the final reduction of DOPO derivative costs and more favorable participation in market competition; The synergistic effect of phosphorus, nitrogen and other non-halogen elements in DOP0 derivatives expands the types of DOPO derivatives and their fields of application. At present, Sichuan Oriental Insulation Materials Co., Ltd. has made great progress in the development and application of DOPO and its derivatives, and has also cooperated extensively with many research institutes such as Beijing Institute of Chemistry, Chinese Institute of Organic Chemistry, and Sichuan University. . It is believed that in the near future, DOPO and its derivatives will not only be epoxy resins, but also contribute more and more to the development of other halogen-free flame retardant materials.
In this respect, research and development are mainly concentrated in two directions: one is to use DOPO derivatives as reactive flame retardants, introduced into the ring resin matrix structure, and then cured to obtain phosphorus-containing epoxy resin; the second is to cure with DOPO derivatives. The agent cures the ordinary epoxy resin to form a phosphorus-containing epoxy resin. In this paper, the new varieties of epoxy resin flame retardants and curing agents used in domestic and foreign DOPO derivatives and the flame retardancy and thermal properties are reviewed. In the development and application of flame retardants, DOPO(I) was reacted with itaconic acid, maleic acid and benzoquinone respectively to obtain three kinds of DOPO derivatives II, III and IV, and I-IV was reacted with epoxy resin to obtain high. Performance epoxy resin, cured product with high Tg, Td and high modulus of elasticity and good flame retardancy, suitable for printed circuit boards and semiconductor packages. U.S. Patent] proposes a new type of flame retardant V, which is formed by the reaction of DOPO with naphthoquinone. This phosphorus-containing epoxy resin exhibits higher curing than tetrabromobisphenol A (TBBA) type cured epoxy resin. Thermal stability and carbonization rate.
In the development of curing agents, DOPO polyphenolic hydroxyl or polyamino derivatives can be used as curing agents for polymers. The properties of epoxy resins cured by them are quite different from those of brominated epoxy resins. Especially in terms of flame retardancy and thermal stability, the difference is obvious. Recent studies have shown that modified phenolic resins formed by introducing DOPO into phenolic resins are more suitable for use as curing agents. There are also two reported modified phenolic resins X and XI which are also useful as curing agents for CNE resins. The product exhibited good thermal stability (>320 ° C), high Tg (159-178 ° C), high char formation rate (N2, 70 ° C, >50%) and LOI value (26-32.5). Compared with DOPO derivative III, these modified phenolic resins have similar properties, but because the modified phenolic resin has better compatibility with the polymer, the process is relatively simple and the cost is lower, so that it can be better promoted. Applications, both of which are useful as curing agents for epoxy resins in semiconductor packages and electronic laminates.
The introduction of DOPO derivatives as flame retardants and curing agents into epoxy resins improves the flame retardancy and thermal stability of epoxy resins, and more importantly, avoids the use of brominated epoxy resins in the process of use and recycling. The pollution caused has opened up a new path for the development of epoxy resin. Experts believe that the development and application of DOPO derivatives in the future will need to solve two or two problems: simplifying the process from DOPO synthesis, reducing costs, laying a solid foundation for the final reduction of DOPO derivative costs and more favorable participation in market competition; The synergistic effect of phosphorus, nitrogen and other non-halogen elements in DOP0 derivatives expands the types of DOPO derivatives and their fields of application. At present, Sichuan Oriental Insulation Materials Co., Ltd. has made great progress in the development and application of DOPO and its derivatives, and has also cooperated extensively with many research institutes such as Beijing Institute of Chemistry, Chinese Institute of Organic Chemistry, and Sichuan University. . It is believed that in the near future, DOPO and its derivatives will not only be epoxy resins, but also contribute more and more to the development of other halogen-free flame retardant materials.
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