Improving the Supercritical CO₂ Foaming of Polypropylene by the Addition of Fluoroelastomer as a Nucleation Agent

Chenguang Yang; Quan Zhao; Zhe Xing; Wenli Zhang; Maojiang Zhang; Hairong Tan; Jixiang Wang; Guozhong Wu

doi:10.3390/polym11020226

Improving the Supercritical CO₂ Foaming of Polypropylene by the Addition of Fluoroelastomer as a Nucleation Agent

Polymers (Basel). 2019 Feb 1;11(2):226. doi: 10.3390/polym11020226.

Authors

Chenguang Yang^{1

2

3}, Quan Zhao⁴, Zhe Xing⁵, Wenli Zhang^{6

7}, Maojiang Zhang^{8

9}, Hairong Tan^{10

11}, Jixiang Wang¹², Guozhong Wu^{13

14}

Affiliations

¹ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. yangchenguang@sinap.ac.cn.
² University of China Academy of Sciences, Beijing 100049, China. yangchenguang@sinap.ac.cn.
³ School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Pudong, Shanghai 201210, China. yangchenguang@sinap.ac.cn.
⁴ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. zhaoquan@htkjbattery.com.
⁵ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. xingzhe@sinap.ac.cn.
⁶ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. zhangwenli@sinap.ac.cn.
⁷ University of China Academy of Sciences, Beijing 100049, China. zhangwenli@sinap.ac.cn.
⁸ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. zhangmaojiang@sinap.ac.cn.
⁹ School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Pudong, Shanghai 201210, China. zhangmaojiang@sinap.ac.cn.
¹⁰ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. tanhairong@sinap.ac.cn.
¹¹ School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Pudong, Shanghai 201210, China. tanhairong@sinap.ac.cn.
¹² Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. wangjixiang@sinap.ac.cn.
¹³ Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Jiading, Shanghai 201800, China. wuguozhong@sinap.ac.cn.
¹⁴ School of Physical Science and Technology, ShanghaiTech University, Haike Road 100, Pudong, Shanghai 201210, China. wuguozhong@sinap.ac.cn.

Abstract

In this study, a small amount of fluoroelastomer (FKM) was used as a nucleating agent to prepare well-defined microporous PP foam by supercritical CO₂. It was observed that solid FKM was present as the nanoscale independent phase in PP matrix and the FKM could induce a mass of CO₂ aggregation, which significantly enhanced the diffusion rate of CO₂ in PP. The resultant PP/FKM foams exhibited much smaller cell size (~24 μm), and more than 16 times cell density (3.2 × 10⁸ cells/cm³) as well as a much more uniform cell size distribution. PP/FKM foams possessed major concurrent enhancement in their tensile stress and compressive stress compared to neat PP foam. We believe that the added FKM played a key role in enhancing the heterogeneous nucleation, combined with the change of local strain in the multiple-phase system, which was responsible for the considerably improved cell morphology of PP foaming. This work provides a deep understanding of the scCO₂ foaming behavior of PP in the presence of FKM.

Keywords: fluoelastomer; heterogeneous nucleation; polypropylene; scCO2 foaming.

Grants and funding

TZ2018004/Science Challenge Project