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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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Transfer reactions of the poly(methyl methacrylate) radical with some solvents
M. Lazár and J. Pavlinec
Slovak Academy of Sciences,
Bratislava
Abstract: Transfer consts. with a solvent during polymerization of methyl methacrylate (I) at 50° in n-heptane, iso-octane and Et, Pr, iso-Pr, Bu, iso-Bu, sec-Bu-, and tert-Bu acetates were detd. An anomaly occurred in the curve of the relation of degree of polymerization P for poly(methyl methacrylate) to a change of S/M, where S/M is the ratio of solvent S to monomer M; if S/M is greater than 0.2 the normal occurrence of this function is disturbed and the transfer const. Cs can be detd. only from the initial occurrence of this relation where the slope of the curve is pos. For the polymerization of I in n-heptane and in iso.ovrddot.octane, Cs values were 1.8 × 10-4 and 1.2 × 10-4, resp. These changes indicate a decrease of termination consts. because of higher solvent concns. The known reactivity of individual C.sbd.H bonds can be applied for the evaluation of transfer consts.
Full paper in Portable Document Format: 156a428.pdf (in Slovak)
Chemical Papers 15 (6) 428–434 (1961)
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