Irgafos 168

Irgafos 168 and Erucamide were purchased from Tokyo Chemical Industry Co. (Tokyo, Japan). Acetone, methanol, chloroform, sodium chloride, potassium chloride, sodium sulfate, ammonium chloride, urea, lactic acid, sodium hydroxide, and 2-propanol were purchased from Kanto Chemical Co. (Tokyo, Japan). Formic acid was purchased from Fluka (Charlotte, NC, USA). Water was generated by PURELAB frex-3 (ELGA, High Wycombe, UK). These reagents were used without further purification. Stock solutions of Irgafos 168 and Erucamide were prepared by dissolving 0.1 g of reagents in 100 mL of Acetone and methanol, respectively. Working solutions were prepared by diluting the stock solutions with methanol.

Ethylene-vinyl acetate (EVA) copolymer, which was used as the thermoplastic, was purchased from TPI Polene Co., Ltd. (Bangkok, Thailand). Natural rubber (NR) sheet (air-dried sheet type) was purchased from Bothong cooperation (Chonburi, Thailand). Dicumyl peroxide (DCP), which was used as a crosslinking agent, was supplied by Arkema (Missouri, North Kansas City, MO, USA). Octadecyl-3-(3,5-di-tert butyl-4-hydroxyphenyl)-propionate (Irganox1076) and tris(2,4-di-tert-butylphenyl)phosphate (Irgafos168), which were used as a thermal stabilizers, were purchased from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan). Asphalt binder (penetration grade, AC60/70) was obtained from Thai Lube Base Co., Ltd. (Bangkok, Thailand) Properties of the EVA, NR, DCP, and asphalt binder are shown in Table 1. Xylene, which was used as solvent to evaluate the gel content of thermoplastic vulcanizate, was used as received without further purification.