Nearly 95% of monomers or chemical intermediates used today are based on fossilized carbon such as coal and petroleum. This has resulted in a high rate of depletion of fossilized reserves, continuous escalation in pet...Nearly 95% of monomers or chemical intermediates used today are based on fossilized carbon such as coal and petroleum. This has resulted in a high rate of depletion of fossilized reserves, continuous escalation in petroleum prices, environmental impact with the increase in emission of greenhouse gases, and accumulation of non-biodegradable waste on earth. Current global main challenges are moving towards green sources - need for vast new and sustainable material resources;supplement, reuse and replace petroleum based polymeric materials;biodegradability of materials to prevent build up of waste;toxicity associated with the preparation, usage and environmental safety. Recent investigations are therefore, focused on procuring materials from the plant resources, agricultural waste and their utility in synthesis of polymeric materials. Amongst the polymers derived from natural resources poly(lactic acid) is a leading candidate. Commercial quantities of natural oil-based polyols such as castor, soya bean oil have been available over the past several years and currently used for synthesis of? polyesters, polyurethanes etc, but today many other? natural materials are also being investigated. It should be possible to produce sustainable polymers commercially and economically.展开更多
文摘Nearly 95% of monomers or chemical intermediates used today are based on fossilized carbon such as coal and petroleum. This has resulted in a high rate of depletion of fossilized reserves, continuous escalation in petroleum prices, environmental impact with the increase in emission of greenhouse gases, and accumulation of non-biodegradable waste on earth. Current global main challenges are moving towards green sources - need for vast new and sustainable material resources;supplement, reuse and replace petroleum based polymeric materials;biodegradability of materials to prevent build up of waste;toxicity associated with the preparation, usage and environmental safety. Recent investigations are therefore, focused on procuring materials from the plant resources, agricultural waste and their utility in synthesis of polymeric materials. Amongst the polymers derived from natural resources poly(lactic acid) is a leading candidate. Commercial quantities of natural oil-based polyols such as castor, soya bean oil have been available over the past several years and currently used for synthesis of? polyesters, polyurethanes etc, but today many other? natural materials are also being investigated. It should be possible to produce sustainable polymers commercially and economically.
