EFFECTS OF INORGANIC OXIDES ON POLYMER BINDER BURNOUT .1. POLY(VINYL BUTYRAL)

The effects of silica, mullite, alpha-alumina, and gamma-alumina on th e nonoxidative thermal degradation of poly(vinyl butyral) are describe d. To varying degrees, all of the inorganic oxides catalyzed reactions that produced butanal. Other significant products included: water, bu tenal, acetic acid, and alkyl aromatics. Two distinct evolution steps were detected for samples containing mullite and alpha-alumina, sugges ting that multiple interactions existed between these oxides and the p olymer. The relative amounts of volatile aromatic products evolved by heating polymer/oxide samples were greater than the amounts generated from the neat polymer. For the polymer/gamma-alumina sample, carboxyla te species were detected on oxide surfaces above 250 degrees C, indica ting that a reaction between the polymer and gamma-alumina occurred. ( C) 1996 John Wiley & Sons, Inc.