PROBING THE POSTGELATION REACTIONS OF EPOXIDIZED NATURAL RUBBER CROSS-LINKED WITH DODECENYL SUCCINIC ANHYDRIDE

Effect of SiO2 Particles on the Relaxation Dynamics of Epoxidized Natural Rubber (ENR) in the Melt State by Time-Resolved Mechanical Spectroscopy

The rheological behavior of an epoxidized natural rubber (ENR) nanocomposite containing 10 wt.% of silica particles was examined by time-resolved mechanical spectroscopy (TRMS), exploiting the unique capability of this technique for monitoring the time-dependent characteristics of unstable polymer melts. The resulting storage modulus curve has revealed a progressive evolution of the elastic component of the composite, associated with slower relaxations of the ENR macromolecular chains. Two major events were identified and quantified: one is associated with the absorption of the epoxidized rubber macromolecules onto the silica surface, which imposes further restrictions on the motions of the chains within the polymer phase; the second is related to gelation and the subsequent changes in rheological behavior resulting from the simultaneous occurrence cross-linking and chain scission reactions within the ENR matrix. These were quantified using two parameters related to changes in the storage and loss modulus components.

Modification of proteins and polysaccharides using dodecenyl succinic anhydride: Synthesis, properties and applications-A review

Proteins and polysaccharides are among the biopolymers produced by living organisms for their structural integrity, protection, physiological functions, or as reserve energy. These biopolymers are extracted from their natural matrices by humans to fulfil basic as well as convenience needs. The inquisitive human nature, ever-growing demands and resources at disposal have led to copious research in the field of biopolymer modifications. The availability of reactive sites on these biopolymers make them suitable substrates for esterification, etherification, oxidation, epoxidation, N-acylation, alkylation, etc. Dodecenyl succinic anhydride (DDSA) is an esterifying agent that introduces a 12-carbon hydrophobic chain in the structure of the substrate containing suitable reactive sites. The use of DDSA as a modifying agent for biopolymers dates back to the mid-twentieth century. Even today, many biopolymers are explored for modification with DDSA for improved functionality. These modifications are aimed at catering the needs of the paint, pharmaceutical, cosmetic, food and textile industries. This review attempts to systematically compile reported research on the use of DDSA as a biopolymer modifying agent, the various reaction techniques, properties and applications thereof.