链转移合成超高韧性凝胶及其性能表征  

Synthesis of Hydrogels with Super High Toughness via Chain Transfer and Its Property Characterization

作　　者：王超[1] 李江波 刘汉超 王义 郑静[1] 

机构地区：[1]四川大学高分子材料与工程国家重点实验室,四川大学高分子科学与工程学院,四川成都610065

出　　处：《塑料工业》2017年第5期147-151,119,共6页China Plastics Industry

基　　金：国家科技重大专项(2016ZX05011-003-002)

摘　　要：利用烯丙基胺的链转移作用,在其水溶液中通过丙烯酰胺和N,N-亚甲基双丙烯酰胺的共聚反应,合成了一种具有超高韧性的凝胶。通过平衡溶胀实验、动态力学实验、机械性能实验以及扫描电镜实验等表征了此超高韧性凝胶(PCPAM凝胶)的结构与性能。拉伸实验显示,相比普通聚丙烯酰胺(PAAM)凝胶,在烯丙基胺的链转移作用下PCPAM凝胶的机械韧性得到了显著提高,主要体现在其断裂伸长率大幅提高。循环压缩实验显示PCPAM凝胶存在明显的机械滞后现象,证实凝胶中存在能量耗散机制。扫描电镜实验显示PCPAM凝胶相比原有PAAM凝胶具有更规整的凝胶结构。所有的结果表明,烯丙基胺的加入可以在保持凝胶交联网络完整的情况下,显著降低凝胶的交联结构的非均匀性,形成部分交联凝胶PCPAM,其未完全交联的支化结构,可通过能量耗散,大幅提高凝胶的韧性。A new type of hydrogels （PCPAM hydrogels） with high toughness was synthesized based on the chain transfer effect of allylamine of crosslinking copolymerization of acrylamide and N, N＇-methylenebis （2-propenamide） in an aqueous solution reactive system. characterized and evaluated via equilibrium swelling The structures and properties of the hydrogel was experiments, dynamic rheology measurement,mechanical properties test and scanning electron microscopy （SEM）, etc. The uniaxial tension tests results show that the PCPAM hydrogels exhibits a remarkable increase in the toughness, in particular the great increase in the elongation at break. Cyclic compression tests show large mechanical hysteresis in PCPAM hydrogels due to the energy dissipation. It can be attributed that the chain transfer reaction of allylamine which leads to forming partly branching chain due to incomplete crosslink. On the other hand the SEM observation shows a more homogeneously multiporous structures in the PCPAM hydrogels, which reveals that chain transfer effect also reduces concentration of crosslinking network density.

关 键 词：链转移作用 韧性凝胶 聚丙烯酰胺 烯丙基胺 

分 类 号：O648.17[理学—物理化学]