Triply Biobased Thermoplastic Composites of Polylactide/Succinylated Lignin/Epoxidized Soybean Oil

Jianbing Guo; Jian Wang; Yong He; Hui Sun; Xiaolang Chen; Qiang Zheng; Haibo Xie

doi:10.3390/polym12030632

Triply Biobased Thermoplastic Composites of Polylactide/Succinylated Lignin/Epoxidized Soybean Oil

Polymers (Basel). 2020 Mar 10;12(3):632. doi: 10.3390/polym12030632.

Authors

Jianbing Guo^{1

2}, Jian Wang^{1

2}, Yong He^{1

2}, Hui Sun³, Xiaolang Chen^{2

4}, Qiang Zheng^{1

2

5}, Haibo Xie¹

Affiliations

¹ Department of Polymer Material and Engineering, College of Materials and Metallurgy, Guizhou University, Guiyang 550025, China.
² National Engineering Research Center for Compounding and Modification of Polymer Materials, Guiyang, Guizhou 550014, China.
³ School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing 100048, China.
⁴ Key Laboratory of Advanced Materials Technology Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
⁵ Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.

Abstract

Soybean oil is beneficial to improve the compatibility between polylactide (PLA) and succinylated lignin (SAL), which leads to the preparation of a host of biobased composites containing PLA, SAL, and epoxidized soybean oil (ESO). The introduction of SAL and ESO enables the relatively homogeneous morphology and slightly better miscibility obtained from triply PLA/SAL/ESO composites after dynamic vulcanization compared with unmodified PLA. The rigidity of the composites is found to decline gradually due to the addition of flexible molecular chains. According to the reaction between SAL and ESO, the T_g of PLA/SAL/ESO composites is susceptible to the movement of flexible molecular chains. The rheological behaviors of PLA/SAL/ESO under different conditions, i.e., temperature and frequency, exhibit a competition between viscidity and elasticity. The thermal stability of the composites displays a slight decrease due to the degradation of SAL and then the deterioration of ESO. The elongation at break and notched impact strength of the composites with augmentation of ESO increase by 12% and 0.5 kJ/m², respectively. The triply biobased PLA/SAL/ESO composite is thus deemed as a bio-renewable and environmentally friendly product that may find vast applications.

Keywords: dynamic vulcanization; epoxidized soybean oil; lignin; polylactide composite.