Journal of the Rubber Research Institute of Sri Lanka
Permanent URI for this collectionhttps://dl.nsf.gov.lk/handle/1/8676
Browse
4 results
Search Results
Item A study of some of the properties of blends of polypropylene and chemical incorporated granular natural rubber(Rubber Research Institute. Agalawatta, 1994) De Silva, K.G.K.; Ranjith, S.L.G.; Warnapura, S.S.Thermoplastic elastormers of plastics natural rubber (TPNR) are generally produced by blending plastics with natural rubber (in bale form) using traditional banbury type internal mixers plastics extruders. This involves high energy consumption also high capital costs of both rubber plastics processing machinery. The production of Thermoplastic elastomers on a continuous basis using extruder blenders has been less applicaple to TPNR blends because natural rubber is not readily or widely available in the required granular form in natural rubber consuming countries. The manufacture of different types of granular rubber in our laboratories has not only made possible the blending of thermoplastics with natural rubber on a continuous basis but also paved the way for producing TPNR blends with improved properties. In this publication the production of different types of granular rubber, the processing characteristics of various compositions of polypropylene natural rubber blends the end product performance of these blends the end product performance of these blends at different temperatures are discussed.Item Kinetic study of the graft polymerization of unsaturated monomers with natural rubber latex and with deproteinized natural rubber latex(Rubber Research Institute. Agalawatta, 1994) De Silva, K.G.K.; Hamielec, A.E.The non-rubber substances present in natural rubber (NR) latex seem to have an influence on the rate of polymerization reaction, degree of grafting grafting efficiency of the graft copolymerization reaction of Methyl Methacrylate on to natural rubber.The released amino acids on enzymatic destruction of phospholipid/protein barrier in natural rubber latex may probably by the cause for the improvement of the reaction kinetics; such that reaction under redox conditions could be conducted without purification of the monomer with inhibitors. Presence of emulsifier, type of enzyme, monomer diffusion time in rubber particle, size of the particle are shown to have an influence on the physical properties of the final product.H NMR has been used to study the composition of the final product.Item Depolymerized natural rubber as a processing aid(Rubber Research Institute of Sri Lanka. Agalawatte, 1996) De Silva, K.G.K.; Silva, S.M.C.E.; Vitharana, L.P.The development of a commercially viable, light coloured, non toxic grade of depolymerized natural rubber by the Rubber Research Institute of Sri Lanka (proprietary) has led us to carry out research and development work on the potential industrial applications of depolymerized rubber, for example, as a speciality rubber in raw rubber blends to improve processability and certain physical properties due to its covulcanizable characteristics. The effects of percentage of depolymerized rubber on the processability and vulcanization characteritics are discussed in this paper. The results show that the use of depolymerized rubber in controlled amount enhances the processability and lowers the power requirement without adversely affecting the properties of the compounds. Also, the results obtained with the vulcanized mixes demostrate that the behaviour of depolymerized rubber is comparable to synthetic polyisoprenes and is an improvement over ordinary processing oils. Results show that the incorporation of certain percentages of depolymerized rubber in the formulations can significatly improve the abrasion resistance. Clearly, if depolymerized natural rubber can surpass the existing processing aids in quality and price, then a much larger market is potentially available world wide.Item Improving phase morphology and properties of NR/NBR blends with compatibilizers(Rubber Research Institute. Agalawatta, 1998) De Silva, K.G.K.; Lewan, M.Two compatibilizing agent have been identified for NR/NBR blend to improve the phase morphology and interfaial adhesion, thereby improving the physical and technological properties. Light and optical microscopy and Nuclear Magnetic Resonance have been used to study the phase contrast and crosslink distribution of the elastomer blends respectively, to suport the observations mode on the improvements in the physical properties of these blends.