| Abstract
| - Hydrolyzable cross-linked star polymer model networks were prepared by the sequential group transfer polymerization of monomer, cross-linker, monomer, and cross-linker with the use of novel hydrolyzable (red core) and nonhydrolyzable (blue core) cross-linkers. Hydrolysis of these materials led to the formation of soluble star polymers.
- A hydrolyzable dimethacrylate cross-linker, 2-methyl-2,4-pentanediol dimethacrylate (MPDMA), wassynhesized by the reaction of 2-methyl-2,4-pentanediol and methacryloyl chloride in the presence oftriethylamine. This cross-linker was used to prepare a neat cross-linker network and three cross-linkedstar polymer model networks (CSPMNs) of methyl methacrylate (MMA), as well as star-shaped polymersof MMA, by group transfer polymerization (GTP). Gel permeation chromatography (GPC) intetrahydrofuran (THF) confirmed the narrow molecular weight distributions (MWDs) of the linear polymerprecursors, and demonstrated the increase in molecular weight (MW) on each successive addition ofcross-linker or monomer. Characterization of the star polymers by static light scattering (SLS) in THFshowed that star polymers with MPDMA cores bear a relatively small number of arms, between 7 and35. All star polymers and polymer networks containing the MPDMA cross-linker were hydrolyzed atroom temperature in neat trifluoroacetic acid to yield lower-MW products.
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