苯胺类扩链剂对聚氨酯渗透汽化膜性能的影响

The Effect of Aniline Chain Extender to the Properties Polyurethane Pervaporation Membrane

采用预聚体分散法,以邻苯二甲酸-1,6-己二醇酯二醇(PH-56)为软段,异佛尔酮二异氰酸酯(IPDI)为硬段,三种不同二胺(分别为乙二胺EDA、对苯二胺PPDA、联苯二胺BPDA)为扩链剂制备了三个系列的水性聚氨酯膜。采用傅里叶变换红外光谱(FTIR)、热重分析(TGA)对膜结构进行表征。对于苯/环己烷(50/50wt.%),测定膜的溶胀率和渗透汽化分离性能。结果表明,含有苯环的二胺扩链所得膜的热稳定性优于乙二胺扩链所得膜,其中联苯二胺系列膜热稳定性最好。配方相同的三种系列膜的溶胀率从大到小依次为EDA系列、PPDA系列、BPDA系列。相同配方条件下,BPDA的分离选择性最好,分离因子最高,为7.51;EDA系列渗透通量最大,最高为9.39J/kg·μm·m-2·h-1。同一系列中,随着胺类扩链剂含量逐渐增加,渗透通量减小,分离因子呈相反趋势。

Three series of waterborne polyurethane membranes with different kinds of chain extender were successfully synthesized using polyphthalic acid-1, 6-glycol polyester diol （PH-56） as soft segment, isophorone isocyanate （IPDI） as hard segment through the method of pre-polymer process in this work. The membranes were characterized using FT-IR, TGA, degree of swelling （DS） determination and pervaporation performance for benzene/cyclohexane （50/50 in wt.% ） in order to probe the influence of benzene ring structure in chain extenders. The results indicated that thermal stability and selectivity of PPDA and BPDA series membrane were better than EDA series membrane, BPDA series were the best. The degree of swelling for BPDA series membrane are the minimum, EDA series membrane are the maximum. When the content of amine chain extender increased, the permeation flux rapidly decreased, the separation factor increased. Selectivity towards benzene of BPDA series membrane are the best ,the maximum separation factor value is 7.51, the EDA series membrane have the largest permeation flux, the maximum value is 9.39J/kg·μm·m^-2·h^-1.