Dynamic Variation of Storage Characteristics and Molecular Structure of Natural Rubber

The quality stability of the natural rubber is a key point to its use in the industries and some special fields. However, due to storage hardening caused by the complicated molecular structure of natural rubber and non-rubber component, the quality uniformity is still not controlled in the nowadays rubber factory. In the previous research, storage hardening phenomena are extensively examined but the special mechanism is controversial and detail information is need to be further revealed. The dynamic evolution of accelerated storage properties and molecular structure of natural rubber have been investigated. The results show that △P increased slowly at first but then increased apparently and PRI has no direct relationship with △P. The storage time of 24 h is the critical storage period in which besides the △P and PRI, the P0, gel content and molecular weight also has obvious transformation. △P has a negative apparent correlation with ester content but protein content is relatively of no account in storage hardening process.