Applications of cardanol in rubber processing

Abstract

This research project explores tlle utilization of cardanol in yarious capacities for rubber processing. Cardanol is a phenol with a 10Ilg side chain ill the meta position of the benzene ring. It is obtained by the vacuum distillation of cashew Hut shell liquid (CNSL) which is a cheap agro-b}1)roduct. In this study, the plasticizer property of cardanol was investigated in silica filled and HAF black filled NR, NllH, EPDM and CR by comparing cure characterisLics and mecharlical properties of vulcanizates containing conventional plasticizer with those containing cardanol as plasticizer. The co-activator, arltioxidant and accelerator properties were investigated in gum samples of NR, NBR, EPDM arld CR by comparing the properties of vulcanizates which contain cOIlventional co-activator, antioxidarlt and accelerator with those in which each of them was replaced by cardanol. The general elfectiveness of cardanol was investigated by determination of cure time , measurement of physical and mecharlical properties, ageing studies, crosslink density, extractability, FTIR spectra, TGA etc. The results show that cardanol can be substitute lor aromatic oil in both silica lilled and HAF black filled NR. Again, it can replace dioctyl phthalate in both silica filled and HAF black filled NBR. Similarly, cardanol Carl replace naphthenic oil in silica filled as well as HAF black filled EPDM and CR. The cure characteristics and mechanical properties are comparable in all the eight cases. The co-activator property of cardanol is comparable to stearic acid in all the four rubbers. The cure characteristics and mecharlical properties in this case are also comparable. The antioxidant, property of cardanol is comparable to TQ in all the four rubbers. The accelerator property of cardarlol is comparable with CllS in the case of NBR and EPDM. No accelerator property is observed in the case of NR. The accelerator property of cardanol in eR is not negligible when compared with TMTD.