A search for effective reclaiming agents was carried out by means of a mechano-chemical reclaiming method for the purpose of crosslink scission of vulcanizates. Triphenyl phosphine, the combinations of p-toluene sulfinic acid with 1, 8-diaza-bicyclo (5, 4, 0) undecne-7 (DBU) or its salts and tetraethylthiuram disulfide with DBU were found to be more effective reclaiming agents. The reclaimed rubbers obtained by means of this method were observed to be hardened after left standing. However, they could easily be softened by remilling several times.
These revulcanizates maintained the values of their tensile strength and elongation at break within 48-67% and 35-48%, respectively. Among others, the revulcanizates having good tensile properties could be obtained by use of reclaiming agents that acted mainly as crosslinking breaker.
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