Mechanism of Cryopolymerization: Diffusion-Controlled Polymerization in a Nonfrozen Microphase. An NMR Study

摘要: Polymerization of dimethylacrylamide (DMAAm) cross-linked with PEG diacrylate was studied using 1H NMR both in situ a semifrozen system and supercooled aqueous system. The amount nonfrozen microphase, which polymerization proceeds, is defined by the concentration starting monomers freezing temperature, depends on depression temperature caused dissolved osmolytes. However, despite there being identical initial concentrations at chosen −10 °C cryopolymerization proceeded different rates depending size microphase. Further studies conditions microphase were performed pulsed gradient spin echo (PGSE) to study self-diffusion solutes. Observations regarding reaction rate rationalized terms degrees long-range diffusion seen PGSE. Cryopolymerization resulted decreasing osmolyte concentration, hen...