A Study of Quality Improvement of Natural Rubber Products by Drying Methods

摘要

This experimental study was carried out to verify the quality enhancement of Natural Rubber Products by drying methods and ascertain to what extent the different methods of drying affected the properties exhibited. During this study, samples of natural rubber coagulum were obtained and a sample each was subjected to one of these three methods of drying: air, smoke and oven. The qualities of the dried rubber samples from the three methods of drying were then investigated. The criterion adopted for quality in this study was Plasticity Retention Index (PRI), which gave insight of the oxidative resistance of natural rubber, a measure of quality. The plasticity retention index was tested by using the Wallace plastimeter. The PRI values were calculated for the samples. Results obtained from this study showed that the qualities of natural rubber samples were actually influenced to different measurable extents depending on drying methods, as exhibited in the PRI levels. The results further gave basis for our conclusions that the smoke dried rubber samples had the poorest qualities, having the lowest values of PRI;followed by the oven and air dried samples respectively in terms of their PRI presented the best qualities, the highest PRI values.