Rapid Solid-State Photopolymerization of Cyclic Acetal-Containing Acrylates.

A cyclic acetal-functionalized urethane acrylate monomer is synthesized here and polymerized in a crystalline state without the polymerization kinetics being deleteriously affected by the solid state. Depending on the processing conditions, the cyclic acetal urethane acrylate monomer exists in either a metastable liquid state or a crystalline state at ambient conditions. Due to mobility restrictions, extremely poor polymerization kinetics and functional group conversions are typically achieved in solid state polymerizations.

Polymerization kinetics of HEMA/DEGDMA: using changes in initiation and chain transfer rates to explore the effects of chain-length-dependent termination.

The effect of kinetic chain length and chain transfer on the polymerization kinetics and network structure in polymerizations of loosely crosslinked 2-hydroxyethyl methacrylate/di(ethylene glycol) dimethacrylate mixtures was explored. Polymerization behavior of the monomer mixture in the presence and absence of a chain transfer agent was monitored at various initiation rates and chain transfer agent concentration levels. Dependence of the polymerization rate on the initiation rate was found to deviate from the classical square-root relationship because of chain-length-dependent termination.