Utility of malonate-initiated polymerizations of methyl methacrylate

✍ Scribed by Jeffrey R. Warmkessel; William J. Brittain; William J. Simonsick Jr.; Michael S. Chisholm

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 154 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19990301)37:5<615::aid-pola11>3.0.co;2-2

✦ Synopsis

We have studied the polymerization of methyl methacrylate with cesium and tetramethylammonium salts of diethyl 2-ethylmalonate carbanion. For polymerizations initiated at room temperature, no effort was made to control the exotherm. The polymerizations proceeded with high conversions and produced polymers characterized by broad polydispersities (M w /M n ϭ 2-3). We consistently observed M n (exptl) Ͻ M n - (calcd) for target ϭ 50,000 -300,000 g/mol; we observed an apparent upper limit for M n of 60,000 -70,000 g/mol. Chain transfer from impurities in reagents was eliminated as the source of molecular weight lowering. Oligomeric samples were analyzed by mass spectrometry; results were best explained by methoxide initiation of the polymerization. No evidence for malonate end groups was observed in the mass spectra.