Alkyl esters of styrenesulfonic acid were synthesized, homopolymerized, and copolymerized with a variety of comonomers. The polymers were investigated for hydrolysis behavior under a variety of reaction conditions. Several methods for the synthesis of alkyl styrenesulfonates were investigated. Methyl, ethyl, n-propyl, and isopropyl styrenesulfonates were successfully synthesized in yields of 65, 55, 50, and 40 percent, respectively, starting with sodium styrenesulfonate. Monomer synthesis procedures involving the sulfochlorination of (2-bromoethyl)benzene were found to be inferior because of sulfone formation which led to insoluble, crosslinked resins. Alkyl styrenesulfonates were homopolymerized and copolymerized by free-radical initiation. Bulk, solution, and emulsion polymerization systems were successfully employed. Comonomers investigated included styrene, acrylamide, acrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, maleic anhydride, sodium styrenesulfonate, and sodium 2-sulfoethyl methacrylate. Copolymerization reactivity ratios (r(,1), r(,2)) for the copolymerization of methyl styrenesulfonate with styrene, acrylic acid, and maleic anhydride were determined. Hydrolysis studies in aqueous dimethyl sulfoxide solutions were performed. The effect of a variety of variables, including copolymerization, solvent, temperature, alkalinity, acidity, and molecular weight, on the kinetics of hydrolysis was investigated. The various homopolymers and copolymers were found to behave similarly to low molecular weight analogs and exhibited the following reactivity towards hydrolysis: methyl > isopropyl > ethyl > n-propyl. However, in solvent systems containing high concentrations of dimethyl sulfoxide ((GREATERTHEQ) 90 vol %) the reaction is characterized by two different steps, a first rapid step analogous to the reaction of low molecular weight alkyl toluenesulfonates, and a second, slower step. This retardation has been attributed to neighboring group effects in which the sulfonic acid groups formed during the hydrolysis reaction "tie" up surrounding water molecules via hydrogen bonding thus inhibiting reaction with and/or solvation of neighboring unreacted ester groups.
Identifer | oai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:dissertations-5795 |
Date | 01 January 1984 |
Creators | VANZO, BRET EDWARD |
Publisher | ScholarWorks@UMass Amherst |
Source Sets | University of Massachusetts, Amherst |
Language | English |
Detected Language | English |
Type | text |
Source | Doctoral Dissertations Available from Proquest |
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