| Abstrakt: |
ABSTRACT Low concentrations of 4-vinylphenylboronic acid (VPBA) were copolymerized with 2- N-morpholinoethyl methacrylate (MEMA) by nitroxide mediated polymerization using BlocBuilder™ unimolecular initiator at 80 to 90 °C. The MEMA/VPBA copolymerizations were performed at initial feed compositions ( fVPBA,0) of 0.05 to 0.10 VPBA, with fVPBA,0 = 0.10 using dimethylacetamide (DMAc) solvent being most effective, as seen by a linear increase in number average molecular weight, Mn, versus conversion and low dispersity, Đ < 1.40. The copolymers were further chain-extended with a second batch of VPBA, resulting in a block copolymer with monomodal molecular weight distribution and Đ = 1.66. For MEMA/VPBA copolymers, increases in VPBA composition and polymer solution concentration resulted in decreases in the cloud point temperature (CPT, typically varied between 27.4-37.8 °C) and CPT increased from 31.2 to 33.8 °C to about 88 °C with decreases in pH from 7 to 4. Rheological tests with small angle light scattering (SALS) confirmed CPTs measured by UV-Vis and DLS. These copolymers were targeted as models to combine possible glucose-sensing boronic acid functionality the thermoresponsiveness provided by MEMA groups. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1560-1572 [ABSTRACT FROM AUTHOR] |
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