The Effect of Curing Parameters on the Mechanical Properties of Styrene-NR Elastomers Containing Natural Rubber-Graft- Polystyrene

บทคัดย่อ

The copolymerization of styrene on natural rubber latex was prepared by an emulsion polymerization using potassium persulfate and sodium laurylsulfate as an initiator and emulsifier, respectively. The vulcanization characteristics of styrene-NR elastomers were studied using moving die
rheometer. The effect of vulcanization on styrene-NR elastomer containing natural rubber-graftpolystyrene was investigated in accelerated-sulphur curing system containing 2.0, 2.5, 3.0, 3.5 phr of sulphur with various temperatures ranging from 130 ^oC to 160 ^oC. Increase of tensile strength resulted from an increase of the crosslink density of vulcanization when compared to uncured sample. Furthermore, the accelerating action of temperature in curing system could be confirmed by increase of curing rate index and rate constant. The value of activation energy of the cure reaction could be calculated as 72.278 kJ/mol.