以膦酰杂菲为侧基的1-戊炔聚合反应及其结构与热力学性质

以2-(6-氧化-6-氢-二苯基(c,e)<1,2>氧杂膦酰基)-1,4-二羟基苯(ODOPB)结构单元为中心,在两侧通过酯化反应分别引入4-(4-戊炔氧基)苯甲酰基和4-丁氧基苯甲酰基,得到了1-戊炔衍生物单体M-34,同时合成了不含9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物(简称膦酰杂菲,DOPO)基元的M-34模型化合物M-0.分别以Rh(nbd)Cl]2和Rh(nbd)B(C6H5)4为催化剂,研究了催化剂浓度和聚合时间对M-34和M-0聚合反应收率的影响.结果表明,由于DOPO存在较大π共轭结构和较强极性效应,降低了催化剂的活性,使得聚合产物P-34分子量较低,但改善了P-34的溶解性,并诱导P-34主链基本采取全反式构型,从而有利于增强侧基之间的相互作用,使这种含有DOPO的聚1-戊炔衍生物呈现良好的热稳定性,且优于其不含DOPO模型聚合物P-0的热稳定性.但同时DOPO的引入也增加侧基的体积,为链段运动提供了较大的自由体积,使得P-34的Tg低于不含DOPO模型聚合物P-0的Tg.

POLYMERIZATION ,STRUCTURES AND THERMAL PROPERTIES OF PHOSPHAPHENANTHRENE-CONTAINING POLY ( 1 -PENTYNE)

The phosphaphenanthrene-containing 1-pentyne monomer(M-34) was synthesized through the successive esterification of 2-(6-oxide-6H-dibenz<1,2>oxaphos-phorin-6-yl)-dihydroxyphenylene(ODOPB) with 4-(4-pentynoxy)benzoyl and 4-butyloxybenzoyl,respectively.Due to the introduction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide(DOPO) group,the catalytic ability of Rh-based catalysts(Rh(nbd)Cl]2 and Rh(nbd)B(C6H5)4) is decreased and the yields of polymer are relatively low.The polymerization of model monomer(M-0) in the absence of phosphaphenanthrene side-group was,however,carried out in high yield at the same condition.The microstructure of the poly(1-pentyne) derivants was characterized by means of 1H-NMR.The experimental results indicate that the main-chains of poly(1-pentyne) derivants with high trans-content configuration are produced due to the strong π-π stacking and polar interactions between phosphaphenanthrene-containing pendent groups.Thus,the interaction between adjacent pendent groups is further strengthened.The molecular weights and distribution of P-34 and its model polymer P-0 were measured by GPC;Their thermal properties were evaluated by TGA and DSC.Comparing with P-0 in the absence of phosphaphenanthrene side-group,TGA analysis reveals the excellent thermal stability of P-34,losing 1% of weights during heating to 270℃ and retaining 50% of weights after pyrolyzis at 550℃.And the char yield of P-34 is over 50 wt% at 550℃.The DSC results indicate that Tg of P-34 is lower than that of P-0 because DOPO increases the volume of side-groups in P-34.