Abstract: A process for preparing phenol-formaldehyde novolak resins and molding compositions in which portions of the phenol normally contained in said resins are replaced by a phenol/neutral fractions extract obtained from fractionating fast-pyrolysis oils. The fractionation consists of a neutralization stage which can be carried out with aqueous solutions of bases or appropriate bases in the dry state, followed by solvent extraction with an organic solvent having at least a moderate solubility parameter and good hydrogen bonding capacity.Phenolic compounds-containing/neutral fractions extracts obtained by fractionating fast-pyrolysis oils from a lignocellulosic material, is such that the oil is initially in the pH range of 2-4, being neutralized with an aqueous bicarbonate base, and extracted into a solvent having a solubility parameter of approximately 8.4-9.11 [cal/cm.sup.3 ].sup.1/2 with polar components in the 1.8-3.0 range and hydrogen bonding components in the 2-4.

Abstract: Polymer compositions comprising poly(benzhydrolimide) chains ending with ethylenic unsaturated groups complying with the general formula: ##STR1## wherein Ar is a divalent aromatic radical and R a hydrogen atom or a monovalent hydrocarbon radical. They can be prepared by reacting, under imidation condition, at least one primary diamine with at least one benzydrol 3,3', 4,4'-tetracarboxylic acid, a bis (ortho-acid-ester) or a tetraester of such acid and with an anhydride, an acid-ester or a diester of dicarboxylic cycloaliphatic acid with ethylenic unsaturation. These compositions may be converted to cross-linked polymides by thermal polyemrization. They can be used in particular for manufacturing composite materials, adhesives, molded articles and protective coatings withstanding high temperatures.