Research

Biodegradable Composites

New phosphate-based glass fibers to incorporate them in a biodegrable polymer matrix are being explored. The goal is to demonstrate the feasibility of a glass-fiber composite material that would degrade rapidly, rather than remaining as trash in the environment for centuries.

There are several challenges that confront the effort to use phosphate fibers in composite materials. For example, to provide high strength and elastic stiffness in the composite, the molecules of the glass should have long "backbones" with strong interatomic bonds. However, to have the fiber dissolve rapidly in soil or water, ionic modifier substances (such as lime, soda etc.) are needed, to promote hydrolysis of the phosphate polymeric structure. The modifiers also lower the viscosity of the liquid material, so that fibers can be drawn at lower temperatures, which would help to keep down the cost of these fibers. Current focus is to find a compromise among the three factors, mechanical properties, degradability, and process temperature.