A development of polylactic acid as bio-based polymers

There is a growing demand for the saving of fossil resources and the reduction of greenhouse gas emissions with the aim of promoting society that is capable of sustainable development. In the area of developing materials as well as in other areas of activities, various efforts are being made for that objective in the aspects of raw materials, manufacturing technology, and disposal of materials after use. Bio-based polymers are attracting attention because of its important role in switching the raw materials from exhaustible resources to annually renewable resources. Polylactic acid has two characteristics. One is that the raw material lactic acid is produced by fermenting starch and saccharides that are derived from various biomass. The other is polylactic acid is biodegradable slowly in the environment and rapidly in compost. This paper introduces polylactic acid as bio-based polymers from the perspective of its life cycle contributing to the saving of fossil resources and the reduction of greenhouse gas emissions. This paper also describes a polylactic acid manufacturing process which is typified by ring opening polymerization and direct polycondensation and discusses the issues to be addressed for the growth of the market for the material.