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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : The Effect of Process Factors on the Mechanical Properties of Styrene-NR Elastomers Containing Natural Rubber-Graft- Polystyrene) ผู้เขียน: ดร.ธาริณี นามพิชญ์, รองศาสตราจารย์ , Polchit Buakaew สื่อสิ่งพิมพ์:pdf AbstractStyrene-NR elastomers containing natural rubber-graft-polystyrene were prepared by an emulsion polymerization using potassium persulfate as an initiator. The effect of process factors on tensile strength was investigated by varying the temperature, rubber-to-monomer ratio, and initiator and emulsifier contents from 50 to 64 ?C, 1.5 to 9, 0.8 to 1.4 g, and 4.5 to 6.5 g, respectively. Experimental results indicated that the tensile strength increased with an increase in reaction temperature, rubber to monomer ratio, and initiator and emulsifier contents. |
 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : The Effect of Curing Parameters on the Mechanical Properties of Styrene-NR Elastomers Containing Natural Rubber-Graft- Polystyrene) ผู้เขียน: ดร.ธาริณี นามพิชญ์, รองศาสตราจารย์ , Polchit Buakaew สื่อสิ่งพิมพ์:pdf AbstractThe 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 ?C to 160 ?C. 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. |
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