It is produced the additive null univalent - which consists of the urethane denaturation novolak in order to improving the adhesiveness of the steel make code and the rigidity

摘要

PROBLEM TO BE SOLVED: To obtain a urethane-modified novolak capable of improving the bonding strength between a rubber and a reinforcing material and giving a reinforced material having improved rigidity without deteriorating the health of worker by reacting a phenol with an oxo compound and a urethane in the presence of an acidic catalyst under specific condition. ;SOLUTION: This urethane-modified novolak free from free phenol used as a raw material is produced by reacting (A) a monohydric or polyhydric phenol such as phenol with (B) an oxo compound (aldehyde or ketone) such as formaldehyde together with (C) a urethane such as a 1-20C alkyl or alkylaryl urethane derived from an alcohol in the presence of (D) an acidic catalyst such as sulfuric acid at a high temperature (60-200°C). Preferably, the compounding ratio of A/B is 1/(0.3-0.95) and that of A/C is 1/(0.005-1).;COPYRIGHT: (C)1998,JPO