Governing effects of melt viscosity on fire performances of polylactide and its fire-retardant systems

Yueming Yu; Liangdong Xi; Miaohong Yao; Linghui Liu; Yan Zhang; Siqi Huo; Zhengping Fang; Pingan Song

doi:10.1016/j.isci.2022.103950

Governing effects of melt viscosity on fire performances of polylactide and its fire-retardant systems

iScience. 2022 Feb 19;25(3):103950. doi: 10.1016/j.isci.2022.103950. eCollection 2022 Mar 18.

Authors

Yueming Yu^{1

2}, Liangdong Xi¹, Miaohong Yao^{1

2}, Linghui Liu^{1

2}, Yan Zhang¹, Siqi Huo¹, Zhengping Fang¹, Pingan Song^{3

4}

Affiliations

¹ Laboratory of Polymer Materials and Engineering, NingboTech University, Ningbo 315100, China.
² College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
³ School of Agriculture and Environmental Science, University of Southern Queensland, Springfield Central, 4300 Australia.
⁴ Centre for Future Materials, University of Southern Queensland, Springfield Central, 4300 Australia.

Abstract

Extreme flammability of polylactide (PLA) has restricted its real-world applications. Traditional research only focuses on developing new effective fire retardants for PLA without considering the effect of melt viscosity on its fire performances. To fill the knowledge gap, a series of PLA matrices of varied melt flow index (MFI) with and without fire retardants are chosen to examine how melt viscosity affects its fire performances. Our results show that the MFI has a governing impact on fire performances of pure PLA and its fire-retardant systems if the samples are placed vertically during fire testing. PLA with higher MFI values achieves higher limiting oxygen index (LOI) values, and a lower loading level of fire retardants is required for PLA to pass a UL-94 V-0 rating. This work unveils the correlation between melt viscosity and their fire performance and offers a practical guidance for creating flame retardant PLA to extend its applications.

Keywords: Materials science; Polymer chemistry.