اصلاح پلي فنول - فرمالدهيد با برخي روغنهاي طبيعي

Modification of Polyphenol - formaldehydes by Some Natural Oils

Phenolic resins are one of the most important polymers, which are applied in adhesives, moulding, coating manufacturing of printed circuit boards and automotive industries. In the present project, modification of phenolic resins has been studied. The effects of different kinds of oils and phenols on curing conditions have been investigated. By application of different phenols the properties have been altered to a great extent, but by different oils it has not been so considerable. With respect to investigation of mechanism of phenol reaction with different modifier oils, it postulated that the oil is C-alkylated on phenol. Finally some laminates were produced by kraft papers and modified phenolic resins. The effect of impregnation time, weight ratio of methanol to toluene and also resin to solvent in resin absorption by kraft papers was studied. The changes of weight ratio of methanol to toluene have no effect on resin absorption by kraft paper. In the first five seconds, the highest percent of resin absorption occurred and the 1:1 weight ratio of resin to solvent was selected as an optimum ratio.