Ordered long polyvinyl alcohol fiber-reinforced thermoplastic starch composite having comparable mechanical properties with polyethylene and polypropylene

Wen Zhou; Dongdong Zha; Xin Zhang; Jie Xu; Bin Guo; Yanan Huang

doi:10.1016/j.carbpol.2020.116913

Ordered long polyvinyl alcohol fiber-reinforced thermoplastic starch composite having comparable mechanical properties with polyethylene and polypropylene

Carbohydr Polym. 2020 Dec 15:250:116913. doi: 10.1016/j.carbpol.2020.116913. Epub 2020 Aug 14.

Authors

Wen Zhou¹, Dongdong Zha¹, Xin Zhang¹, Jie Xu², Bin Guo³, Yanan Huang⁴

Affiliations

¹ College of Science, Nanjing Forestry University, Nanjing, 210037, China.
² State Key Laboratory for Hubei New Textile Materials and Advanced Processing Technology, College of Materials Science and Engineering, Wuhan Textile University, Wuhan, 430200, China.
³ College of Science, Nanjing Forestry University, Nanjing, 210037, China; Agricultural and Forest Products Processing Academician Workstation of Henan Province, Luohe, 462600, China; Post-Doctoral Research Center of Henan Nanjiecun Group, Luohe, 462600, China. Electronic address: gbm@ustc.edu.
⁴ Agricultural and Forest Products Processing Academician Workstation of Henan Province, Luohe, 462600, China; Post-Doctoral Research Center of Henan Nanjiecun Group, Luohe, 462600, China.

PMID: 33049833
DOI: 10.1016/j.carbpol.2020.116913

Abstract

A novel strategy is proposed to fabricate ordered long polyvinyl alcohol fiber (PVAF)-reinforced thermoplastic starch (TPS) composites with significantly improved mechanical properties. The PVAFs were uniformly fixed on two rods first; then sandwich-like TPS/fibers/TPS composite films were prepared by hot pressing, and PVAFs (0-4.08 wt%) with the same orientation were added to the composite films. The tensile test demonstrated that the tensile strength of the PVAF/TPS composite film improved from 2.13 MPa for TPS to 20.98 MPa with 4.08 wt% PVAFs, which is higher than the tensile strength of polyethylene (PE) (11.88 MPa) and polypropylene (PP) (19.29 MPa) and ten times higher than that of TPS. The sandwich-like cross-section of the composite film was observed by scanning electron microscopy to prove the better compatibility between PVAF and TPS. The nanoindentation test revealed that the addition of fibers improved the elastic modulus and hardness of the surface of the material. The strengthening mechanism for different PVAF contents was simulated by finite element analysis and attributed to the reduced maximum von Mises stress at the interface between the fiber and the TPS matrix, avoiding the stress concentration and corresponding fracture. This study provides a new way to prepare degradable composite films with suitable mechanical properties to replace PE or PP.

Keywords: Composite film; Fiber orientation; Finite element; Polyvinyl alcohol fiber; Thermoplastic starch.