热塑性碳硼烷聚羟基酯醚的合成及热稳定性能

Synthesis,Characterization,and Thermostability of Thermoplastic Carborane-Containing Poly(hydroxy ester ethers)

以o-碳硼烷双酚二缩水甘油醚和丁二酸、4,4-二羧基二苯醚为原料,四苯基溴化磷为催化剂,设计合成了2种碳硼烷聚羟基酯醚(P1和P2)。通过红外光谱、核磁共振和凝胶渗透色谱表征了所得聚合物的结构,结果表明得到了预期结构的聚羟基酯醚。通过差示扫描量热分析和热重分析(TG)评价其热性能,研究了碳硼烷结构对玻璃化转变温度(Tg)、初始分解温度和残炭率的影响。结果表明,P1和P2的Tg分别为-20.6℃和12.8℃,比不含碳硼烷的聚羟基酯醚(P0)高,表明大体积刚性碳硼烷笼形结构的引入提高了聚羟基酯醚的玻璃化转变温度。TG分析结果显示,碳硼烷笼形结构能在高温下极大地提升聚羟基酯醚的耐烧蚀性能,空气氛围下P1和P2的残炭率高于氮气氛围。

Two novel o-carborane-containing poly(hydroxy ester ethers)(P1 and P2)were synthesized from o-carborane bisphenol diglycidyl ether,succinic acid,and 4,4′-oxybisbenzoic acid in the presence of tetraphenylphosphonium bromide as catalyst.The obtained polymers were characterized by FT-IR,NMR,and gel permeation chromatography(GPC),and indicating that poly(hydroxy ester ethers)with anticipated structure were obtained.Glass transition behavior was studied by differential scanning calorimetry(DSC),and results show that the Tg of P1 and P2 is-20.6℃and 12.8℃,respectively,higher than that of polyhydroxy ester ether without carborane(P0),indicating that large-volume rigid carborane cages can increase the glass transition temperature of poly(hydroxy ester ether).Thermal stability was also studied by thermogravimetric analyzer(TGA).Results show that the carborane cage structure merges into polyhydroxy ester ethers,greatly improves the ablation resistance at high temperature.In air atmosphere,the char yield of P1 and P2 is higher than that in nitrogen atmosphere;this is because boron in the carborane structure can react with oxygen to form B-O-B bonds.