Polysaccharide-derived plastics for low-dielectric films in high-frequency electronics and transparent optical fibers
摘要
Modern communication technology relies on two principal electromagnetic systems: wireless communication using radio waves and optical communication using light. In these systems, petroleum-based plastics serve two distinct functions: as electrical insulators for radio-frequency circuits and as transparent waveguides for optical signal transmission. However, the growing demand for carbon neutrality calls for materials that combine high performance with renewability. This review summarizes our recent efforts to develop polysaccharide-based plastics suitable for advanced communication devices. (1) Thermoplastic polysaccharide esters were designed to combine high-heat resistance with low-dielectric properties for high-frequency electronic substrates. By tuning the molecular backbones and side-chain structures, these esters achieved high glass-transition temperatures (>200 °C) and low-dielectric properties (dielectric constant < 3.0, dielectric loss factor < 0.010), comparable to or surpassing those of conventional petroleum-based plastics. (2) Thermally and mechanically robust pullulan fibers were developed for optical waveguides. Using an all-aqueous gel-spinning process, amorphous pullulan fibers were obtained with high transparency, blue-to-near-infrared light transmission, tensile strength of approximately 200 MPa, and thermal stability up to 200 °C. These findings demonstrate that polysaccharides, as renewable molecular architectures, can provide high-performance and sustainable materials capable of supporting next-generation communication infrastructure.