Flow-induced crystallization precursor structure in high molecular weight isotactic polypropylene (HMW-iPP)/low molecular weight linear low density polyethylene (LMW-LLDPE) binary blends

被引：12

作者：

Keum, Jong Kahk ^{[1
]}

Mao, Yimin ^{[1
]}

Zuo, Feng ^{[1
]}

Hsiao, Benjamin S. ^{[1
]}

机构：

[1] SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA

来源：

POLYMER | 2013年 / 54卷 / 04期

基金：

美国国家科学基金会;

关键词：

Flow-induced crystallization; Polypropylene; WAXS/SAXS; PHASE-SEPARATION; POLYMER MELTS; LIGHT-SCATTERING; INDUCTION PERIOD; EARLY-STAGE; POLY(ETHYLENE-TEREPHTHALATE); ORIENTATION; BEHAVIOR; TIME; MISCIBILITY;

D O I：

10.1016/j.polymer.2012.12.067

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 formation of initial crystallization precursor induced by flow was investigated by synchrotron-based wide- and small-angle X-ray scattering techniques (WAXS/SAXS), using polymer blends consisting of high molecular weight isotactic polypropylene (HMW-iPP) and low molecular weight linear low density polyethylene (LMW-LLDPE) as model systems. LMW-LLDPE, the dominant component, served as the amorphous matrix. Crystallization behavior of the blends with three different HMW-iPP concentrations, i.e., 3, 6 and 9 wt%, were examined at temperatures higher than the blends' cloud points, in a time-resolved manner. It was found that the formation of a flow-induced precursor of crystallization was strongly influenced by the concentration of HMW-iPP in the blends. The blend with low HMW-iPP content (3 wt%) was not able to form a shear-induced crystalline structure. As the concentration of HMW-iPP increased, crystallization kinetics, crystallinity, and lamellar orientation were greatly enhanced. (C) 2012 Elsevier Ltd. All rights reserved.

引用

页码：1425 / 1431

页数：7

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