Abstract
The effect of temperature and solvent on polymer tacticity in free-radical polymerization of styrene and methyl methacrylate was studied by 13C and 1H NMR, respectively. Polystyrene shows a mild syndiotactic tendency (Pm = 0.36 ± 0.02) that is independent of temperature over a wide range (-10 to 120°C), while poly(methyl methacrylate) shows a stronger syndiotactic tendency (Pm = 0.17 ± 0.01 at 30°C) that decreases as temperature is increased (Pm = 0.22 ± 0.02 at 80°C). None of the polymerization solvents studied (bulk, THF, DMF, DMSO, acetonitrile, and acetone) had a significant effect on polymer tacticity in either system. The triad fractions of both polymers showed deviations from the Bernoulli model, implying that the antepenultimate unit affects the propagation reaction.
Original language | English |
---|---|
Pages (from-to) | 3351-3358 |
Number of pages | 8 |
Journal | Journal of Polymer Science, Part A: Polymer Chemistry |
Volume | 51 |
Issue number | 16 |
DOIs | |
Publication status | Published - 15 Aug 2013 |