Isobutyraldehyde phenol novolak resins prepn. - by mixing isobutyraldehyde with a phenol in presence of mineral or Lewis acid in solvent-free melt, for use as rubber tackifiers

摘要

Isobutyraldehyde-phenol polycondensates of novolak type are prepd. by reacting isobutyraldehyde with a phenol in mol. ratio of 2-0.5:1 (0.8-1.3:1) in the presence of a strong inorganic acid or a Lewis acid. Process takes place in the melt, in absence of solvents. The polycondensates are used as adhesive agents for rubber. Other uses are: prepn. of adhesive mixts., wood glues, esp. binders for chipboard; sand core binders; and anti-ageing additives. Yields are quantitative. Tackiness improvement, partic. in natural rubber, is higher than that achieved with standard tackifiers, e.g. coumarone-, hydrocarbon- and known phenol resins.