A commercial grade of isotactic PP (700J) was supplied by Thai
Polypropylene Co., Ltd. Vetiver grass (Vetiveria Zizanioides) was
obtained from The Land Development Department, Nakhon Ratchasima,
Thailand. The ages of vetiver grass were around 6–8
months. Two types of rubber were used including NR and EPDM.
Natural rubber grade STR 5L was supplied by Thai Hua Rubber
Co. Ltd. and EPDM was purchased from Chemical Rubber Co. Ltd.