"Preparation and water-swelling properties of grafted natural rubber based water-swellable rubber"

Abstract

Deproteinized natural rubber （DPNR) latex was selected as the substrate for the modified rubber, the grafting copolymerization of acrylic acid （AA) monomer on DPNR chain was achieved and a type of hydrophilic AA modified DPNR copolymer （DPNR-g-PAA) was prepared based on the free ra-dical emulsion graft copolymerization of allyl of rubber macromolecule chain and vinyl monomer in the presence of re-dox initiating system, and the molecular structure, cross-sectional morphology, and water-swelling properties of DPNR-g-PAA were characte-rized by Fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectroscopy, scanning electron microscopy, and gravimetric method. The results showed that the water absorption rate of DPNR-g-PAA film as water-swellable rubber could reach 85.06%, and the surface moisture permeability of DPNR was significantly improved. Compared with the traditional process of physical blen-ding or solution grafting copolymerization, DPNR-g-PAA prepared by the free radical emulsion graft copolymerization had certain advantages.

Keywords

• deproteinized natural rubber latex， acrylic acid， water-swellable rubber， graft copolymerization， water absorption rate， water-swelling property，