Synthesis of Particle Double-Network Gels by Redox Polymerization

Particle double-network (P-DN) gels are one of the high-strength gels that are usually synthesized by photopolymerization. In this study, we synthesized P-DN gels by redox polymerization. To decide the ratio of the most suitable polymerization initiator and catalyst, we synthesized several kinds of P-DN gels by changing each ratio at a time, and performed compression tests. P-DN gels with a small amount of the polymerization initiator and catalyst showed high strength. In particular, P-DN gels with 0.2 mol% of the polymerization initiator and 0.1 mol% of the catalyst (percentages according to the monomer) showed a higher compression stress compared to the P-DN gels synthesized by photopolymerization. The moisture content of both gels was approximately equal. In addition, P-DN gels gelated after two hours for the redox polymerization process, which is shorter than for the photopolymerization process and thus advantageous for large-scale synthesis.