C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
C08C—TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS
C08C19/00—Chemical modification of rubber
C08C19/30—Addition of a reagent which reacts with a hetero atom or a group containing hetero atoms of the macromolecule
C08C19/34—Addition of a reagent which reacts with a hetero atom or a group containing hetero atoms of the macromolecule reacting with oxygen or oxygen-containing groups
C08C19/36—Addition of a reagent which reacts with a hetero atom or a group containing hetero atoms of the macromolecule reacting with oxygen or oxygen-containing groups with carboxy radicals