Green Chemistry in Manufacturing
Today’s fossil fuel-based plastics are not manufactured according to the Principles of Green Chemistry. They rely primarily upon inherently hazardous chemicals -- chemicals that are likely to be carcinogens, neurotoxicants or endocrine disruptors. In short, chemicals that are unhealthy for humans and the environment.
Examples abound of the inherent toxicity of the fossil fuel-based plastics.
- Polyvinyl chloride plastic is made from the carcinogens -- vinyl chloride monomer and ethylene dichloride.
- Polystyrene plastic is made from a carcinogen, benzene.
- Polycarbonate is made from the endocrine disruptor, bisphenol A.
The most effective means for reducing the risks from toxic chemicals is to reduce hazard, that means, to prevent the use of inherently hazardous chemicals in the first place. Green chemistry as defined by Anastas and Warner (1999) is the “the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products.”
The 12 Principles of Green Chemistry define an alternative path to manufacturing plastics that is based on the pursuit of processes that reduce and eliminate the use or generation of hazardous substances in the design, manufacture and application of chemical products. Principles of Green Chemistry that are especially important to moving plastics manufacturing to inherently less toxic chemicals are:
- Design safer chemicals and products: Design chemical products to be fully effective, yet have little or no toxicity.
- Design less hazardous chemical syntheses: Design syntheses to use and generate substances with little or no toxicity to humans and the environment.
- Use safer solvents and reaction conditions: Avoid using solvents, separation agents, or other auxiliary chemicals. If these chemicals are necessary, use innocuous chemicals.
- Design chemicals and products to degrade after use: Design chemical products to break down to innocuous substances after use so that they do not accumulate in the environment.
- Minimize the potential for accidents: Design chemicals and their forms (solid, liquid, or gas) to minimize the potential for chemical accidents including explosions, fires, and releases to the environment.
The goal of integrating chemistry into plastics manufacturing is to create a production system that uses inherently less hazardous chemicals for each step in the process of converting basic chemicals into complex polymers.