ISSN:
0887-624X
Keywords:
methyl methacrylate
;
emulsion polymerization
;
in situ surfactant
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A “surfactant-free” emulsion polymerization of methyl methacrylate was conducted at 80°C with ammonium persulfate initiator. The water-soluble MMA-based oligomers re-maining were isolated and analyzed both as-produced and after hydrolysis. NMR analysis revealed that the mole ratio of MMA repeat units to sulfate end groups in the former is 6.5. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and gel permeation chromatography both showed that the mean number of MMA repeat units comprising the extracted material is 8-9. The hydrolysis procedure rids the oligomers of their terminal groups and converts some of the methyl ester groups to acid, greatly sim-plifying the mass spectrum. This appears to be the first direct measurement of “surfactants” produced in situ from monomer and persulfate initiator. © 1995 John Wiley & Sons, Inc.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1995.080331402
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