文献类型：期刊文献

英文题名：Toughening mechanism of long chain branched polyamide 6

作者：Xu, Menglong[1,2];Lu, Jiawei[1];Qiao, Yongna[2];Wei, Linfeng[2];Liu, Tao[1];Lee, Patrick C.[2];Zhao, Ling[1];Park, Chul B.[2]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Multiphase Mat Chem Engn, Shanghai 200237, Peoples R China;[2]Univ Toronto, Dept Mech & Ind Engn, 5 Kings Coll Rd, Toronto, ON M5S 3G8, Canada

年份：2020

卷号：196

外文期刊名：MATERIALS & DESIGN

收录：;EI(收录号：20204009264192);WOS:【SCI-EXPANDED(收录号:WOS:000588273300007)】；

基金：This research was funded by the National Key Research and Development Program of China, grant number 2016YFB0302200. Also, this research was supported by the China Scholarship Council (No. 201906740084) during the work at the University of Toronto.

语种：英文

外文关键词：PA6; Long chain branching; Rheological percolation; Impact strength

摘要：Polyamide 6 (PA6) materials with different degrees of long chain branching (LCB) were prepared via extrusion through varying the addition of chain extender. The LCB degree was quantitatively determined by using a rheological method based on macromolecular dynamic models. The topological structures of long-chain branching and crosslinked network were effectively distinguished through rheological percolation analysis so that modified PA6 with ultra-high LCB level was obtained. The XRD analysis indicated that LCB modification favored the generation of the gamma-form, and the gamma-form content of LCB-PA6 increased with increasing degree of LCB, which could provide a reasonable explanation for the high Izod impact strength of ultra-high LCB-PA6. Another reason for the great enhancement of impact toughness was the strong interfacial interaction between LCB molecules and virgin PA6 matrix. A large number of fibrillar ligaments and cavities during crack propagation were observed in the SEM analysis. (c) 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).