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合成了含有取代联苯及烷基硅取代基的二芳基乙炔单体(1a～1d),以TaCl5-n-Bu4Sn作催化剂聚合得到聚合物2a、2b和2d。所得聚合物在常规有机溶剂中具有良好的溶解性。用聚合物2a和2b的甲苯溶液浇铸制备了均质膜。采用三氟乙酸对聚合物2a和2b膜进行去硅化反应,制备了不溶性膜3a和3b。热重分析表明,所得聚合物均具有高的热稳定性,在空气中的热失重起始温度分别为340和430℃。聚合物2a和2b的氧气渗透系数(PO2)分别为260和390 barrers,去硅化膜3a和3b的PO2分别下降至73和180 barrers。聚合物膜的O2/N2分离系数为2.4～3.3,并随PO2的增加而减小。由气体在聚合物膜中的扩散系数和溶解系数的测定,扩散系数的降低是导致去硅化膜气体渗透系数下降的主要原因。
Diarylacetylene monomers (1a-1d) containing substituted biphenyls and alkylsilyl substituents were synthesized and polymerized with TaCl5-n-Bu4Sn as catalysts to obtain polymers 2a, 2b and 2d. The resulting polymer has good solubility in conventional organic solvents. Homogeneous membranes were prepared by casting with toluene solutions of polymers 2a and 2b. The polymers 2a and 2b films were subjected to a silicidation reaction using trifluoroacetic acid to prepare insoluble films 3a and 3b. Thermogravimetric analysis showed that the polymers obtained all had high thermal stability, and the initial temperatures of TG in air were 340 and 430 ℃, respectively. The oxygen permeability coefficients (PO2) of polymers 2a and 2b were 260 and 390 barrers, respectively, and the PO2 of desiliconized films 3a and 3b decreased to 73 and 180 barrers, respectively. The O2 / N2 separation coefficient of the polymer membrane is 2.4 ~ 3.3, and decreases with the increase of PO2. From the determination of the diffusion coefficient and the solubility coefficient of the gas in the polymer film, the decrease of the diffusion coefficient is the main reason for the decrease of the gas permeability coefficient of the desiliconized film.