光引发丙烯酰胺表面沉淀接枝聚合反应

Study on Precipitation - Photografting Polymerization of Acrylamide(AM)

利用称量法、水接触角,研究紫外光引发的丙烯酰胺/丙酮(AM/AC)体系在聚丙烯(PP)膜表面沉淀接枝聚合反应的特征,系统考察了单体浓度、光敏剂浓度、溶剂中水含量对沉淀接枝聚合反应的影响,利用ATR-FTIR技术研究了溶剂对接枝链在PP膜表面分布的影响。利用SEM技术观察了接枝膜表面形貌,接枝链聚集在表面呈现球冠状结构,且接枝链团大小基本都为200～300 nm;接枝膜经良溶剂处理后,接枝链比较舒展,易形成片状结构;而经不良溶剂处理后,接枝链卷曲成团,形成孤立的球状结构。

Precipitation - photografting polymerization was investigated with acrylamide grafted onto the surface of polypropylene (PP) film. Surface grafting predominated in polymerization process during initial 30 s of irradiation. When irradiation time increased, yield of grafted polymer increased slowly because precipitation screened out ultraviolet (UV),and thus yield of homopolymer increased greatly. Principal factors affecting surface photografting polymerization such as irradiation time, AM and benzophenone ( BP) concentration, and solvent type were investigated systematically. Effect of solvent on distribution of graft chains on PP film surface was studied by ATR - FTIR. Topography of grafted film was investigated by SEM. Grafted chains on surface conglomerated in round structure size of 200 - 300 nm. In good solvent, grafted chains stretched to form flake structure,while in poor solvent they curled to form round configuration.