The Polymer Society of Korea

Abstract

Spider silk, renowned for its outstanding mechanical properties, is recognized as one of the strongest biomaterials in nature. This study examines the influence of spider silk proteins on the crystallinity, microstructure, and interfacial characteristics of polyethylene oxide (PEO). The findings indicate that these proteins effectively inhibit PEO crystallization, expanding the amorphous phase while significantly enhancing the mechanical properties of PEO. Consequently, PEO/spider silk protein blends emerge as promising candidates for applications such as solid-state polymer electrolytes and CO₂ separation membranes. When employed as solid electrolytes in lithium-metal batteries, the blends exhibit a 35-fold increase in ionic conductivity, a 10-fold improvement in toughness, and a 4-fold enhancement in interfacial adhesion compared to pure PEO-based electrolytes. These improvements result in effective suppression of lithium dendrite formation and yield superior cycling performance in LiFePO4|Li cell tests at 25 °C. In CO₂ separation applications, the blend membranes demonstrate an increase in CO₂ permeability from 22.6 to 109.5 barrer and an enhancement in CO₂/N₂ selectivity from 45 to 64 relative to pure PEO membranes.