Study on Reduction of Zinc Oxide Level in Rubber Compounds

摘要

In the 1st Part of this paperthe results of our study on influence of the interphase transfer catalyst 18-crown-6-ether on sulphur vulcanisation of IR and SBR compounds and vulcanisate properties were presented. To elucidate the mechanism of the activation of sulphur vucanisation by the crown-ether mentioned, additional studies have been undertaken. The influence of other interphase transfer catalysts - crown ethers with a smaller cavity radius (15-crown-5-etherand 12-crown-4-ether) and polyethylene glycol) (PEG) on sulphur vulcanisation of IR compounds has been investigated. Tensile properties of prepared vulcanisates were measured. Their dielectric response was recorded to evaluate the concentration of ions. ~(13)C-NMR spectra of the mixtures containing zinc oxide, stearic acid, TBBS, 18-crown-6-ether and sulphur were measured to establish possible chemical structures formed during vulcanization process. On the bases of the measurements simplified models of the complexes of 18-crown-6-ether and PEG with zinc ion were proposed.