Preparation of diene-based nanoparticles by semibatch microemulsion polymerization and their catalytic hydrogenation

Abstract

Poly(acrylonitrile-co-butadiene) nanoparticles were synthesized by semibatch microemulsion polymerization. The microstructure of the polymers was characterized by 1H NMR and FT-IR. The particle size of the nitrile butadiene rubber (NBR) latex could be well controlled by reaction temperature, surfactant concentration, and feeding time of monomer. The minimum particle size of 34.2 nm could be achieved by using the surfactant/monomer mass fraction of 7.9 wt%. The latex can be directly catalyzed for hydrogenation using Wilkinson's catalyst (RhCl(PPh3)3) and second generation Grubbs catalyst (Grubbs II), respectively. The hydrogenated products (HNBR) with a degree of hydrogenation above 95 mol% were obtained. The fast rate of hydrogenation demonstrates the unique advantages of small particle size.