Commercial grades of Rubber Seed Oil (RSO) and Cashew Nut Shell
Liquid (CNSL) were obtained from M/s.Murugesan & Sons, Coimbatore
and M/s. Adarsh Cashews, Sanoor, India, respectively. Natural rubber
(grade, Ribbed Smoked Sheets, RSS-5) was purchased from the local
market. Commercial grades of rubber chemicals such as zinc oxide
(White seal; ACPL-P999), sulfur (‘Rub-O-Sulf’), mercaptobenzothiazole
(MBT, ‘PILCURE’) and stearic acid (‘Lubstric’; Godrej Industries Ltd.)
were obtained from M/s. Ceyenar Chemicals, Kottayam, India. Kaolin
(grade-BCK) was supplied by M/s. English India Clays, Ltd.,
Thiruvananthapuram. Precipitated silica (‘Ultrasil VN3’ from ‘INSILCO
Ltd.’, Gajraula, UP, India; specific surface area 180 m2/g; density
0.277 g/cm3) was obtained from M/s. Ceyenar Chemicals, Kottayam,
India.