光接枝聚合制备双极膜的影响因素研究

以丙烯酸(AA)为接枝单体,二苯甲酮(BP)为主引发剂,二乙烯基苯(DVB)、新戊二醇二丙烯酸酯(NPGDA)为交联剂,在均相阴离子交换膜表面,通过光接枝聚合得到聚丙烯酸型阳离子交换层,形成单片型双极膜结构.考察了光照时间、交联剂用量、引发剂浓度等对光接枝聚合反应的影响.不加交联剂时,单纯以BP为引发剂,接枝程度随反应时间延长而增加,但接枝程度低;交联剂的加入可明显的提高接枝程度,在反应时间为60s左右,接枝程度最大;NPGDA做交联剂时,接枝程度高于二乙烯基苯;以2,4,6-三甲苯甲酰基-二苯基氧化膦(TPO)为共引发剂,NPGDA用量为单体量的2.5%时,接枝程度最高,为30.1%.采用均聚型引发剂与接枝型引发剂(BP)复配,可提高接枝程度,但在浓度相同时接枝程度最低.

STUDY ON PREPARATION OF BIPOLAR MEMBRANE BY PHOTOGRAFTING POLYMERIZATION

The single-sheet bipolar membrane was synthesized via photografting polymerization of acrylic acid onto the surface of commercial homogeneous anion exchange membrane with benzophenone(BP) as the main initiator,and divinyl benzene(DVB) or neopentylene glycol diacrylate(NPGDA) as crosslink agent.It was found that without the presence of the crosslink agent and benzophenone as single initiator,the grafting degree increased with the prolongation of irradiation time.The grafting degree had a maximum at 60 second when the crosslink agent was added,and the effect of NPGDA was better than that of DVB.The grafting degree incresed when the composited initiator was used.When polymerization was initiated by the compound of BP and 2,4,6-Trimethyl Benzoyl Diphenylphosphine Oxide(TPO),and the dosage of NPGDA was 2.5% mol concentration of monomer,the grafting degree came up to 30.1%.