PMIA/PDAPs复合超滤膜的制备与性能研究

以聚间苯二甲酰间苯二胺(PMIA)为制膜原料,以氧化自聚合法制备的聚多巴胺纳米粒子(PDAPs)作为改性剂添加到PMIA铸膜液中,通过相分离法制备PMIA/PDAPs复合超滤膜,研究了PDAPs含量对复合膜的形貌、结构及性能的影响。结果表明:PDAPs粒径集中分布在380~410nm,当PDAPs质量分数小于等于0.2%时,PDAPs在PMIA基体中的分散性较好,并且在清洗后依然保留在膜体中;随着PDAPs含量的增加,复合膜的水接触角先下降后升高,水通量先升高后下降,牛血清蛋白(BSA)截留率下降,可逆通量恢复率则不断提高;与纯PMIA膜相比,当PDAPs质量分数为0.2%时,复合膜的水接触角下降了11%,水通量由原来的337.4L/(m^2·h)提高到410.4L/(m^2·h),对BSA蛋白质分子的截留率由87%降低至83%,可逆通量恢复率由72.9%提高到84.7%,复合膜表现出良好的亲水性和抗污性能。

Preparation and properties of PMIA/PDAPs composite ultrafiltration membranes

Poly(m-phenyleneisophthalamide)/polydopamine(PMIA/PDAPs)composite ultrafiltration membranes were prepared by phase separation from poly(m-phenyleneisophthalamide)(PMIA)as raw material and polydopamine nanoparticles(PDAPs)prepared by oxidative self-polymerization as modifier added into PMIA casting solution.The effects of PDAPs content on the morphology,structure and properties of the composite membranes were studied.The results showed that the particle size distribution of PDAPs ranged from 380 to 410 nm;PDAPs had the favorable dispersibility in PMIA matrix and remained in the membrane after cleaning when the mass fraction of PDAPs was less than or equal to 0.2%;the water contact angle of composite membranes first decreased and then increased,the water flux first increased and then decreased,the retention rate of bovine albumin(BSA)decreased,and the recovery rate of reversible flux increased with the increase of PDAPs content;compared with those of pure PMIA membrane,the water contact angle of composite membrane decreased by 11%,the water flux increased from 337.4 L/(m^2·h)to 410.4 L/(m^2·h),the retention rate of BSA protein decreased from 87%to 83%,and the reversible flux recovery rate increased from 72.9%to 84.7%when the mass fraction of PDAPs was 0.2%;and the composite membrane showed good hydrophilicity and anti-fouling performance.