Study And Application On The Vulcanization Of Lanthanum Diethyldithiocarbamate As Rubber Accelerator

Rare earth rubber accelerator is a kind of multifunctional additives which has both vulcanization accelerating effect and thermo-oxidative aging resistant property.There are many researches focused on the application' of this kind of rubber accelerator but mainly are based on nonpolar rubber matrix such as NR and SBR.The dispersion and vulcanization promotion effect of Lanthanum diethyldithiocarbamate(LaDC)may be significantly different in polar and non-polar matrix.In this thesis,the vulcanization promotion effect of lanthanum diethyldithiocarbamate(LaDC)in two kinds of rubber matrixes contained the polar rubber(NBR)and non-polar rubber(EPDM)is discussed.LaDC synthesized from LaCl3·7H2O and sodium diethyldithiocarbamate was used as a rubber vulcanization accelerator in nitrile butadiene rubber and ethylene propylene diene rubber.The vulcanization characteristics,crosslink density,physical and mechanical properties,thermal aging resistance and thermodynamic behavior of the uncured and cured rubber composites with different contents of carbon black,active agent and accelerator were tested.The results showed that LaDC could exhibit a high vulcanization accelerating efficiency as vulcanization accelerator in nitrile butadiene rubber matrix even without active additives(ZnO and stearic acid),and it was found that the acrylonitrile group in NBR played an important role in vulcanization process.While in the EPDM rubber matrix,compared with the traditional accelerator,LaDC has longer scorch time,lower vulcanization efficiency and crosslink density,but better thermal aging resistant property.LaDC has both great vulcanization accelerating property and good aging resistant property which is expected to be a new kind of multifunctional rubber additive.