Ultra-high expansion linear polypropylene foams prepared in a semi-molten state under supercritical CO2

被引：59

作者：

Hou, Junji ^{[1
]}

Zhao, Guoqun ^{[1
]}

Wang, Guilong ^{[1
]}

Zhang, Lei ^{[1
]}

Dong, Guiwei ^{[1
]}

Li, Bo ^{[1
]}

机构：

[1] Shandong Univ, Minist Educ, Key Lab Liquid Solid Struct Evolut & Proc Mat, Jinan 250061, Shandong, Peoples R China

来源：

JOURNAL OF SUPERCRITICAL FLUIDS | 2019年 / 145卷

基金：

中国国家自然科学基金;

关键词：

Polypropylene; Supercritical CO2; Batch foaming; Crystals; In-situ visualization; THERMAL-CONDUCTIVITY; LOW-DENSITY; CRYSTALLIZATION BEHAVIOR; RHEOLOGICAL PROPERTIES; CELL NUCLEATION; FABRICATION; STRENGTH; POLYETHYLENE; FOAMABILITY; COMPOSITES;

D O I：

10.1016/j.supflu.2018.11.017

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

To prepare high expansion foams, the crystal melting behavior of linear polypropylene (LPP) under different CO2 pressures was studied using an in-situ visualization method. It was found that with increasing temperature, the crystal boundaries were gradually melted. However, the melting window of the crystals was narrow. In this narrow window, we thought the high expansion LPP foams could be prepared by batch foaming. To verify this, foaming experiments were carried out. The results showed that at the temperature when crystals were nearly melted, the foam had an ultra-high expansion ratio of 45. This demonstrated that the semi-molten state was an important factor for preparing high expansion foams. The thermal insulation and compression performance of the foams were also studied. The lowest thermal conductivity was 37.2 mWm(-1) K-1. The compression tests showed that the collapse stress decreased with an increasing expansion ratio and increased with a decreasing cell size.

引用

页码：140 / 150

页数：11

共 53 条

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