Producing Polyurethane Foam from Natural Oil

摘要

As part of the effort to reduce our dependence on fossil fuels, The Dow Chemical Company has been developing a seed oil based polyol to be used as a replacement to conventional petrochemical based polyether polyols in the production of flexible polyurethane foam. The general process for making natural oil polyols consists of four steps. In the first step, a vegetable oil (triglyceride) is transesterified with methanol, liberating glycerin, and forming fatty acid methyl esters or FAMEs. In the second step the FAMEs are hydroformylated giving a complex mixture of FAMEs that contain 0-3 formyl groups per chain. In the third step, the aldehydes and the remaining unsaturates are hydrogenated to yield a mixture of FAMEs that contain 0-3 hydroxymethyl groups. Finally, the poly(hydroxymethyl)fatty esters are transesterified onto a suitable initiator to produce the natural oil polyol.