Abstract
A study was carried out to understand the processing behaviour of smoked sheet rubber manufactured using natural rubber field latex (NRFL) preserved using ammonia at different concentrations. The NRFL preserved with sodium sulphite was used as a control together with un-preserved NRFL. The NRFL preserved using different ammonia concentrations were kept for different time intervals before further processing. Sheet rubber was manufactured using the preserved latex according to the standard manufacturing procedures. Preservation ability, acid requirement for coagulation, drying characteristics, and the raw rubber properties and mechanical properties of sheet rubber were evaluated. The results revealed that the ammonia concentration should exceed 0.15% to keep the latex for more than a day without pre-coagulation. As the ammonia concentration is higher, the acid requirement was higher. Sheet rubber manufactured using ammoniated latex takes marginally longer time to reach complete dryness. The ammonia concentration and time of preservation has a significant effect on raw rubber properties other than un-aged rapid plasticity number. There was no significant effect (p>0.05) on the mechanical properties other than aged-tensile, tear properties and rebound resilience at aged state.
Highlights
Natural rubber field latex (NRFL) exuded from the rubber tree
Fresh NRFL has to be preserved with a suitable preservation system before it converts into industrially-valuable semi raw materials such as sheet rubber, crepe rubber, technically specified Standard Lanka Rubber (SLR) and centrifuge latex
The increase on ammonia concentration had a significant effect on the latex (p
Summary
Natural rubber field latex (NRFL) exuded from the rubber tree Arg.) is a stable colloidal dispersion of natural rubber (cis 1.4 polyisoprene) agglomerates surrounded by a protective layer of proteins and phospholipids in an aqueous medium. It contains many other nonrubber constitutes such as protein, carbohydrates, antioxidants, fatty acids, enzymes and carotenoid like pigments, etc. Formic, acetic and propionic acids are generated in latex. These acids neutralize the negative charges distributed around the rubber agglomerates causing unintended coagulation or pre-coagulation. Fresh NRFL has to be preserved with a suitable preservation system before it converts into industrially-valuable semi raw materials such as sheet rubber, crepe rubber, technically specified Standard Lanka Rubber (SLR) and centrifuge latex
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
