Abstract
Liquid epoxidised natural rubber (LENR) is a low molecular weight form of epoxidised natural rubber (ENR) which was prepared via degradation of the said rubber in latex stage with redox reagent as degrading agents. The chemical behaviour of ENR latex as a starting material and LENR as a product upon storage were studied. The number average molecular weight (Mn), weight average of molecular weight (Mw), gel content and epoxidation level of ENR latex were consistent as the storage time increased. This indicated that the ENR latex was stable and suitable to be used up to six months of storage as the starting material for LENR preparation. The molecular weight of LENR prepared in reactor scale (LENR B) decreased by 24% from LENR A which prepared in laboratory scale. There were slight changes in the ring opening which was confirmed by nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. It was observed the properties of LENR such as molecular weight, epoxidation level, epoxy derivatives and gel content were almost consistent for one year of storage at room temperature.
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Acknowledgements
The authors would like to thank the Malaysian Rubber Board for the research funding (SEAC-S17SRP0653B) and permission to publish this paper. Mr. Badroll Hisham Mohd Nazir, Mr. Hamdan Abu Bakar, Mr. Hishamuddin Samat, Mr Muhammad Saiful Mohamad Arip, Mr. Mohd Faizal Abd Aziz, Mr.Shafuddin Omar, Mrs Faezah Ismail Mrs Siti Mahirah.Romli are acknowledged for their excellent technical assistance.
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Darji, D., Yusof, N.H., Rasdi, F.R.M. et al. Characterisation of liquid epoxidised natural rubber (LENR) upon storage. J Rubber Res 24, 435–446 (2021). https://doi.org/10.1007/s42464-021-00112-9
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DOI: https://doi.org/10.1007/s42464-021-00112-9