Studies on the Utilisation of Rubber Reclaim in Elastomers

Content Provider	CUSAT-Thesis
Advisor	Dr.Narayanankutty,Sunil K
Researcher	Nelson, P A
Abstract	The thesis describes utilisation of reclaimed rubber, Whole TyreReclaim (WTR) produced from bio non- degradable solid pollutant scrapand used tyres. In this study an attempt has made to optimize thesubstitution of virgin rubber with WTR in both natural and synthetic rubbercompounds without seriously compromising the important mechanicalproperties. The WTR is used as potent source of rubber hydrocarbon andcarbon black filler. Apart from natural rubber (NR), Butadiene rubber (BR),Styrene butadiene rubber (SBR), Acrylonitrile butadiene rubber (NBR) andChloroprene rubber (CR) were selected for study, being the most widelyused general purpose and specialty rubbers. The compatibility problem wasaddressed by functionalisation of WTR with maleic anhydride and by usinga coupling agent Si69.The blends were systematically evaluated with respectto various mechanical properties. The thermogravimetric analyses werealso carried out to evaluate the thermal stability of the blends.Mechanical properties of the blends were property and matrixdependant. Presence of reinforcing carbon black filler and curatives in thereclaimed rubber improved the mechanical properties with the exception ofsome of the elastic properties like heat build up, resilience, compression set.When WTR was blended with natural rubber and synthetic rubbers, as theconcentration of the low molecular weight, depolymerised WfR wasincreased above 46-weight percent, the properties deteriorates.When WTR was blended with crystallizing rubbers such as naturalrubber and chloroprene rubber, properties like tensile strength, ultimateelongation were decreased in presence of WTR. Where as in the case of blends of WTR with non-crystallizing rubbers reinforcement effect wasmore prominent.The effect of functionalisation and coupling agent was studied inthree matrices having different levels of polarity(NBR, CR and SBR).Thegrafting of maleic anhydride on to WTR definitely improved the propertiesof its blends with NBR, CR and SBR, the effect being prominent inChloroprene rubber.Improvement in properties of these blends could also achieved byusing a coupling agent Si69. With this there is apparent plasticizing effect athigher loading of the coupling agent. The optimum concentration of Si69was 1 phr for improved properties, though the improvements are not assignificant as in the case of maleic anhydride grafting.Thermal stability of the blend was increased by using silane-couplingagent.
File Format	PDF
Language	English
Publisher Institution	Cochin University of Science & Technology
Access Restriction	Open
Subject Keyword	Rubber Reclaim Elastomers
Content Type	Text
Educational Degree	Doctor of Philosophy (Ph.D.)
Resource Type	Thesis