PROCESSING STABILIZERS FOR RUBBER COMPOUNDING

摘要

The invention describes an improved method for the preparation of rubber compounds which comprises compounding the rubber and the components at 125 - 200°C in the presence of an amount of 0.1 - 2% based on the weight of the rubber of a processing stabilizer of the formula (I) wherein R<SUB>1</SUB> is hydrogen, C<SUB>1</SUB>-C<SUB>20</SUB>alkyl, styryl, a-methyl-styryl or -CH<SUB>2</SUB>-S-R<SUB>3</SUB>; or C<SUB>1</SUB>-C<SUB>20</SUB>alkyl substituted with C<SUB>2-</SUB>C<SUB>20</SUB>alkenyl, C<SUB>3</SUB>-C<SUB>20</SUB>alkinyl, C<SUB>5</SUB>-C<SUB>9</SUB>cycloalkyl, phenyl or tolyl; R<SUB>2</SUB> is C<SUB>1</SUB>-C<SUB>20</SUB>alkyl or -CH<SUB>2</SUB>-S-R<SUB>3</SUB>, R<SUB>3</SUB> is C<SUB>1</SUB>-C<SUB>20</SUB>alkyl; with phenyl, hydroxyl, cyano, formyl, acetyl or -O-CO-R<SUB>5</SUB> substituted C<SUB>1</SUB>-C<SUB>20</SUB>alkyl; C<SUB>2</SUB>-C<SUB>20</SUB>alkenyl, C<SUB>3</SUB>-C<SUB>20</SUB>alkinyl, C<SUB>5</SUB>-C<SUB>9</SUB>cycloalkyl; or with hydroxyl, phenyl, 4-chloro-phenyl, 2-methoxycarbonylphenyl, p-tolyl, 1,3-benzthiazol-2-yl, -(CHR<SUB>5</SUB>)<SUB>n</SUB>COOR<SUB>6</SUB> or -(CHR<SUB>5</SUB>)<SUB>n</SUB>CONR<SUB>7</SUB>R<SUB>8</SUB> substituted C<SUB>5</SUB>-C<SUB>9</SUB>cycloalkyl; R<SUB>4</SUB> is hydrogen or methyl, R<SUB>5</SUB> is hydrogen or C<SUB>1</SUB>-C<SUB>6</SUB>alkyl, R<SUB>6</SUB> is C<SUB>1</SUB>-C<SUB>20</SUB>alkyl; with oxygen or sulfur interrupted C<SUB>3</SUB>-C<SUB>20</SUB>alkyl; C<SUB>5</SUB>-C<SUB>9</SUB>cycloalkyl, phenyl, benzyl or tolyl, R<SUB>7</SUB> and R<SUB>8</SUB> are independently of each other hydrogen or C<SUB>1</SUB>-C<SUB>6</SUB>alkyl, and n is 1 or 2.