Polymerization of N‐vinylcarbazole. II. Kinetic studies on polymerizations involving azoisobutyronitrile and benzoyl peroxide

Abstract

The polymerization of N‐vinylcarbazole at 60°C in benzene has been initiated with azoisobutyronitrile, benzoyl peroxide, and their mixtures. The kinetics indicate that the azonitrile and the peroxide promote polymerizations of fundamentally different types. The resulting polymers have been examined by gel‐permeation chromatography. The polymer produced with benzoyl peroxide contains a small amount of a high molecular weight fraction which, from the point of view of end groups, resembles the polymer made by use of the azonitrile. It is concluded that benzoyl peroxide in this system gives rise to two types of polymerization which occur simultaneously.

Reactions of vinyl ethers with 2-cyano-2-propyl and benzoyloxy radicals

“…It is possible that vinyl ethers could react with BPO by a one-electron transfer process, as in the cases of N-vinylcarbazole 14,15 and N-vinylpyrolidone 15 ; there is however no evidence for such a reaction for the vinyl ethers in the presence of STY or MMA at comparatively high concentration, and there seems to be no need to consider it in the present connection.…”

“…This possibility might be tested by using a suitably labeled reactant, such as 14 C-BPO, and performing isotope dilution analyses for the product. This study unfortunately cannot be performed because the facilities for work with 14 C-labeled materials are no longer available. There is support for the belief that reactions such as (3) may be involved when BPO is used to initiate polymerizations of monomers such as MMA and STY in the presence of a vinyl ether.…”

Initiator selectivity during free radical copolymerizations of styrene and methyl methacrylate initiated by anaerobic copper(II) oxidation of carbon‐13 labeled acetophenone

“…Several groups have summarized and discussed relative reactivities of monomers toward various radicals. 60,61 Values of k S /k MMA for various carbon-centered radicals are arranged as follows in order of increasing magnitude: HOCH 2 (5.25). With the exception of the hydroxyl-substituted radicals, which merit separate consideration, the electron-withdrawing ability of the radical substituents in this series (hydrocarbon > ester > nitrile $ ketone) generally increases as the k S / k MMA values increase.…”

Selective Adsorption of Aqueous Phase Co‐Oligomers on Latex Particles Part 1: Influence of Different Initiator Systems

“…The composition of these low molecular weight materials (DP n = 100-1000) are strongly influenced by the initiation step. One of the pioneering studies on the effect of initiator on monomer addition was done by Bevington et al [5] Work of Dossi also showed the selectivity of initiator radicals for different monomers. [6] He established the polar effect as an influencing parameter for the rate of addition of initiator toward different monomers.…”