主链含芳基均三嗪环结构杂萘联苯共聚芳醚腈的结构与性能

THE RELATIONSHIP OF STRUCTURE AND PROPERTY OF COPOLY(PHTHALAZINONE ETHER NITRILE PHENYL-1,3,5-TRIAZINE)S

以含均三嗪环结构的双氟单体2,4-二(4-氟苯基)-6-苯基-1,3,5-三嗪与商用2,6-二氟苯腈为共聚单体,与具有扭曲、非共平面结构的4-(4-羟基-苯基)-2H-二氮杂萘-1-酮(DHPZ)经溶液亲核取代逐步聚合,合成了一系列主链含三芳基均三嗪环结构和二氮杂萘酮结构线性共聚芳醚腈(PPENPs),其特性黏数为0.65～1.02 dL/g;采用FTIR和1H-NMR证明了聚合物结构与设计一致.PPENPs的DSC曲线中只有一个玻璃化转变温度,在301～337℃之间,且随着分子链中三嗪环结构的增加而升高.N2气氛5%热失重温度在510℃以上,800℃残碳率大于60%.当共聚物中三嗪环含量低于50%时,在室温下可溶于N-甲基吡咯烷酮(NMP)、N,N-二甲基乙酰胺(DMAc)和氯仿(CHCl3)等极性非质子溶剂中.其薄膜的拉伸强度为72～84 MPa,断裂伸长率为7.6%～11%,且随着分子链中三嗪环结构的增加而降低.

A series of poly（phthalazinone ether nitrile）s containing phenyl-s-triazine ring moiety in the main chain has been synthesized by the nucleophilic displacement polycondensation reaction of 2, 4-bi （4- fluorophenyl） -6-phenyl-1,3,5-triazine （BFPT） , a kind of heterocyclic aromatic difluoride monomer containing phenyl-s-triazine ring moiety, and 2,6-difuorobenzonitrile, as coreactants, with bisphenol-like monomer 4-（4- hydroxylphenyl） （2H）-phthalazin-l-one （DHPZ）. The structures of the copolymers were detected by FTIR and 1H-NMR spectra. The obtained polymers having inherent viscosities in the range of 0.65 - 1.02 dL/g have no crystallinity peaks in their X-ray diffraction patterns,indicating that they are amorphous. The polymers exhibit only one Tg,suggesting that PPEP containing phenyl-s-triazine segments and PPEN containing nitrile segments in the copolymer are miscible. Their glass transition temperatures （Ts） are in the range of 301 -337~C. They exhibit high thermal stability with no significant weight loss up to 500~C in nitrogen （in N2：Td5~ 〉 510~C ） , and the char at 800~C is more than 60%. The content of phenyl-s-triazine in the polymer backbone is more effective in improving the thermal properties than that of nitrile. The Tg and TdS~ of the copolymers increase with increasing the content of phenyl-s-triazine structure in the main chain. However, the copolymers containing lower than 50% phenyl-s-triazine structure could be soluble in NMP, DMAc and chloroform at room temperature. The copolymers having more than 50% phenyl-s-triazine moiety could resolve in NMP and DMAc at heating. All films of the polymers synthesized possess good mechanical properties in the room temperature. Their tensile strengths are ranging from 72 MPa to 84 MPa with 7.6% - 11% of elongation at break,which decreases with incorporating more phenyl-s-triazine moiety in the polymer backbone.