Vinyl polymerization kinetics

This monomer polymerizes faster ia 50% water than it does ia bulk (35), an abnormaHty iaconsistent with general polymerization kinetics. This may be due to a complex with water that activates the monomer it may also be related to the impurities ia the monomer (eg, acetaldehyde, 1-methyl pyrroHdone, and 2-pyrroHdone) that are difficult to remove and that would be diluted and partitioned ia a 50% aqueous media (see Vinyl polymers, A/-VINYLAMIDE POLYPffiRS). 

Fig. 2. Main steps of reaction kinetics, where chain initiation is identical to other vinyl polymerizations.

In studies of the polymerization kinetics of triaUyl citrate [6299-73-6] the cyclization constant was found to be intermediate between that of diaUyl succinate and DAP (86). Copolymerization reactivity ratios with vinyl monomers have been reported (87). At 60°C with benzoyl peroxide as initiator, triaUyl citrate retards polymerization of styrene, acrylonitrile, vinyl choloride, and vinyl acetate. Properties of polyfunctional aUyl esters are given in Table 7 some of these esters have sharp odors and cause skin irritation. 

Ram ford, C.l I. Barb, W.G. Jenkins, A.D. Onyon, P.F. The Kinetics of Vinyl Polymerization by Radical Mechanisms Butter worths London. 1958. 

For less polar monomers, the most extensively studied homopolymerizations are vinyl esters (e.g. VAc), acrylate and methacrylate esters and S. Most of these studies have focused wholly on the polymerization kinetics and only a few have examined the mierostructures of the polymers formed. Most of the early rate data in this area should be treated with caution because of the difficulties associated in separating effects of solvent on p, k and initiation rate and efficiency. 

The Kinetics of Vinyl Polymerization by Radical Mechanisms. Butterworths, London, 1958. 

C. H. Bamford, W. G. Barb, and A. D. Jenkins, The Kinetics of Vinyl Polymerization by Radical Mechanisms, Academic Press, New York, 1958, 117. 

The objective of the present work was to determine the influence of the light intensity on the polymerization kinetics and on the temperature profile of acrylate and vinyl ether monomers exposed to UV radiation as thin films, as well as the effect of the sample initial temperature on the polymerization rate and final degree of cure. For this purpose, a new method has been developed, based on real-time infrared (RTIR) spectroscopy 14, which permits to monitor in-situ the temperature of thin films undergoing high-speed photopolymerization, without introducing any additive in the UV-curable formulation 15. This technique proved particularly well suited to addressing the issue of thermal runaway which was recently considered to occur in laser-induced polymerization of divinyl ethers 13>16. 

The kinetics of vinyl polymerization by radical mechanisms" Butterworth Scientific London, 1958, pp. 103-117. 

It is interesting to note that due to their industrial importance, free radical polymerizations are the most studied reactions in chemistry. Furthermore, the kinetic approaches taken in this chapter are experimentally verified for essentially all typical free radical vinyl polymerizations. 

The polymerization kinetics of alkali salts of living vinyl polymers In ethereal solvents, such as tetrahydrofuran CD, tetrahydropyran (2), dlmethoxyethane Q), oxepane (4) and dloxane... 

The information available up to 1965 on the polymerization kinetics of vinyl acetate has been reviewed by Lindemann 184% who collected data on the transfer coefficients with monomer and polymer, which may be denoted as Clm and Clp respectively. These are the ratios of rate constants for attack on monomer or polymer (per monomer unit) to the propagation rate constant they are the... 

The emulsion polymerization of vinyl hexanoate has been studied to determine the effect of chain transfer on the polymerization kinetics of a water-insoluble monomer. Both unseeded and seeded runs were made. For unseeded polymerizations, the dependence of particle concentration on soap is much higher than Smith-Ewart predictions, indicating multiple particle formation per radical because of chain transfer. Once the particles have formed, the kinetics are much like those of styrene. The lower water solubility of vinyl hexanoate when compared with styrene apparently negates its increased chain transfer, since the monomer radicals cannot diffuse out of the particles. 

Kinetics of vinyl polymerizations in heterogeneous conditions. J. Poly-... 

W. G. Barb, A. D. Jenkins and P. F. Onyon The kinetics of vinyl polymerizations by radical mechanisms. New York Academic Press 1958. 

Imoto, M., and H. Takatsugi Vinyl polymerization. XVIII. Kinetics of the polymerization of acrylonitrile in benzene. Makromol. Chem. 23, 119—127... 

Conix, A., and G. Smets Benzoyl peroxide initiated polymerization kinetics of vinyl monomers in various solvents. J. Polymer. Sci. 10, 525 (1953). 

The synthetic aspects of coordination catalysis still receive far more attention than mechanistic aspects, and precious little can be said with assurance concerning the mechanisms of the foregoing polymerization reactions. Almost the opposite is true of the free radical initiation of vinyl polymerization by metal carbonyls. Bamford et al. (10,11) have studied the kinetics of several such reactions and arrived at plausible interpretations of their results. The initiation of methyl methacrylate polymerization by tetracobalt dodecacarbonyl in the presence of carbon tetrachloride was studied in detail and the results were rationalized in terms of the following mechanism ... 

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