| abstract |
The invention relates to novolac resins obtained by condensation (A) of an aromatic compound containing at least two hydroxyl groups and (B) of an unconjugated diene in an (A)/(B) molar ratio of between 0.7 and 1.75 in the presence of an acidic catalyst, which are characterized in that the content of free aromatic compound is lower than 5% by weight. Also disclosed are a process for the preparation of the resins, and rubber-based compositions including from 0.5 to 20 parts by weight of the above mentioned novolac resins per 100 parts by weight of rubber. The invention also relates to the use of the resins or rubber-based compositions in the field of vulcanization, especially of tires and of conveyor belts. |