材料期刊网

以枝化剂为超支化聚酰胺6(PA6)的引发剂,配以含有端羧基官能团的有机改性剂改性的有机蒙脱土(O-MMT),经原位开环接枝聚合制备了 O-MMT/超支化PA6复合材料。通过 FTIR和TEM表征了超支化 PA6与O-MMT的接枝情况以及O-MMT在基体中的分散形态。研究了O-MMT对超支化P A 6结晶性能、熔体流动性能和力学性能的影响。结果表明：O-MMT呈剥离态和插层态分散于超支化PA6基体中,且与PA6分子链段产生化学键合,形成网络交联结构。网络交联结构使O-MMT/超支化PA6复合材料与超支化PA6相比熔体流动指数急剧下降。另外,O-MMT使超支化 PA6的α晶型消失,且使仅有γ晶型的超支化 PA6的结晶度降低。但随O-MMT 含量增加,O-MMT/超支化P A 6复合材料的强度逐步提高,拉伸强度从38.4 MP a提高至60.8 MP a。复合材料的韧性也得到大幅度提高,断裂伸长率从2.1%提高至70.1%,无缺口冲击强度从20.3 kJ/m2急剧提高至291.8 kJ/m2。

With branched agent as the initiator of hyperbranched polyamide 6 (PA6),with organic modifier modi-fied organic montmorillonite (O-MMT)which has the terminal carboxyl group,O-MMT/hyperbranched PA6 com-posites were prepared via in situ ring-opening graft polymerization.The grafting condition of hyperbranched PA6 and O-MMT,dispersing morphology of O-MMT in matrix were characterized by FTIR and TEM,and the effects of O-MMT on crystallization properties,melt flow properties and mechanical properties of hyperbranched PA6 were studied.Results show that O-MMT is exfoliated and intercalated dispersing in hyperbranched PA6 matrix,and chemically bonds with PA6 molecular chains to form crosslinked network structure,which makes the melt flow in-dex of O-MMT/hyperbranched PA6 composites decrease sharply compared with hyperbranched PA6.In addition, O-MMT can make theα-crystal of hyperbranched PA6 disappear,and make crystallization degree of hyperbranched PA6 with onlyγ-crystal decrease.However,with the increase of O-MMT content,the strength of O-MMT/hyper-branched PA6 composites increase gradually,the tensile strength increase from 38.4 MPa to 60.8 MPa,the tough-ness of composites also has been greatly improved,the elongation at break increases from 2.1% to 70.1%,the un-notched impact strength increases from 20.3 kJ/m2 increase to 291.8 kJ/m2 sharply.