Lanxess offers alternative curing process for EPDM Thursday, May 1, 2014 São Paulo, Brazil - At this year’s edition of Expobor, Lanxess Keltan Elastomers business unit presented an innovative curing technology for EPDM rubber. The basic finding of Lanxess’ rubber experts is that zeolite can be used as a new co-activator for resol curing, enabling both high cure speed and high curing efficiency. Resol curing opens up an alternative approach of EPDM rubber processing besides established sulphur vulcanization and peroxide curing which are the main crosslinking technologies for EPDM rubber. So far, resol curing could be designated as the “work horse” for the dynamic vulcanization of EPDM/PP-based thermoplastic vulcanizates (TPVs). However, for thermoset vulcanization of EPDM it is hardly used, because it is considered to be too slow and suffers from marching cure. Dr. Niels van der Aar, head of Technical Service & Application Development at Keltan Elastomers, explained: “Although emphasis of our studies is on the activation of various resol curing systems for EPDM rubber, it is also shown that this novel way of activation is applicable for resol cure of other types of rubber, including (X)IIR, CR, (H)NBR, BR, SBR and NR.” Depending on the particular resol curing system and rubber under investigation, the cure rate is strongly increased. This means a reduction of scorch and vulcanization times up to 75 percent. Furthermore, the final degree of crosslinking is clearly enhanced, almost up to the double value. “Resol curing can now be considered as a realistic alternative to sulfur and peroxide curing systems making curing at lower temperatures possible and giving, e.g., improved heat aging properties,” said van der Aar. “Finally, it will also be shown that zeolite activation is effective not only for the thermoset vulcanization of EPDM, but also for the dynamic vulcanization of EPDM-based TPVs, enabling a reduction of the resol content and, thus, improving the TPV color characteristics.” Keltan Elastomers is the preferred partner for innovations and bringing new solutions to customers supported by an extensive, global, technical service network, supplying the best grades to support this new solution. (Source: Rubber World)