Effects of processing history and annealing on polymorphic structure of nylon-6/montmorillonite nanocomposites

被引：73

作者：

Xie, SB ^{[1
]}

Zhang, SM ^{[1
]}

Liu, HJ ^{[1
]}

Chen, GM ^{[1
]}

Feng, M ^{[1
]}

Qin, HL ^{[1
]}

Wang, FS ^{[1
]}

Yang, MS ^{[1
]}

机构：

[1] Chinese Acad Sci, Inst Chem, Key Lab Engn Plast, Joint Lab Polymer Sci & Mat, Beijing 100080, Peoples R China

来源：

POLYMER | 2005年 / 46卷 / 14期

关键词：

nylon-6; nanocomposite; crystal structure;

D O I：

10.1016/j.polymer.2005.03.094

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

The effects of processing history and annealing treatment on the thermal property and polymorphic Structure of nylon-6/clay nanocomposites (NCNs) have been investigated. The nanocomposites, including intercalated and exfoliated ones, were prepared by extruding nylon-6 (N6) with sodium montmorillonite (Na-MMT) or organo-montmorillonite (OMMT), respectively. DSC analysis revealed multiple melting endotherms in either the extruded or the injection-molded N6 and NCNs samples. It has been observed that a small exothermic peak around 195 degrees C just before the lower melting peak in the skin regions. We demonstrated that this sub-T-m transition was directly related to the processing-induced shear stresses. WAXD analysis was further performed to characterize the polymorphic structure of injection-molded N6 and NCNs before and after annealing. Annealing at a temperature (80 degrees C) above the T-g of N6 resulted in increase of the absolute content of gamma-form in the skin regions and of the relative content of gamma-form in the core regions of NCNs. In particular, annealing only leaded to increase the fraction of gamma-form in the exfoliated N6/OMMT nanocomposites, which might be related to a confining effect of MMT platelet on the polymer chains mobility. (c) 2005 Elsevier Ltd. All rights reserved.

引用

页码：5417 / 5427

页数：11

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