Comparative Investigation on the Reclamation of NR Based Latex Products with Amines and Disulfides

Abstract

Abstract The latex industry has expanded over the years to meet the world demands for gloves, condoms, latex thread, etc. Due to the strict specifications for the products and the unstable nature of the latex, as high as 15% of the final latex products are rejected. Since waste latex rubber (WLR) represents a source of high quality rubber hydrocarbon, it is a potential candidate for generating reclaimed rubber of superior quality. In the present investigation, two reclaiming agents for WLR vulcanizates were studied in a thermo-mechanical reclaiming process. Parameters investigated were the concentration of the reclaiming agents, as well as reclaiming temperature and time required for proper reclamation. The efficiency of the reclamation process was studied by measurement of the Mooney viscosity, sol-gel analysis and swelling measurements. The ratio of main-chain scission to crosslink scission was studied and the distribution of mono-, di-, and polysulfidic crosslinks was analyzed by thiol-amine reactions. Of the two chemicals investigated, diphenyldisulfide proves itself very effective as reclaiming agent. On the other hand, amines are not suitable as reclaiming agents, because they result in the formation of crosslinks compared to the case where no reclaiming agent is used for reclaiming.