Bioinspired Sustainable Polymer with Stereochemistry-Controllable Thermomechanical Properties
Xin Qi, Yingdong Zhang, Liqun Zhang, Dongmei Yue
Abstract
The regulation of polymer properties based on stereochemistry is essential but rarely studied. Inspired by the isomerization of unsaturated phospholipids in cell membranes, we report a novel method of preparing stereocontrolled polymer using sustainable Eucommia ulmoides gum (EUG) as a raw material. Under the catalysis of thiyl radical, EUG with 100% trans-1,4-polyisoprene structure isomerized to cis -configuration partly in a controllable way, thus achieving the rational modulate of thermomechanical properties. The isomerization mechanism was verified by density functional theoretical calculation. The isomerized EUG (IEUG) with low cis content (≤8.7%) can serve as plastics or shape memory materials, while high cis content (≥10.7%) IEUG transferred into elastomer materials. Especially for IEUG-10.7%, its vulcanizates without filler reinforcement shows high tensile strength (15.5 MPa) and elasticity (97%) comparable to natural rubber due to its strain-induced crystallization ability, which has the potential to be the second natural rubber. This paper provides a new strategy for stereocontrol of polymer properties, and the prepared materials have broad application prospects in the intelligent sensing and rubber industry.