Free radical terpolymerization of three non-homopolymerizable monomers, 1 Kinetic scheme

Abstract

In previous papers two models were proposed which describe the terpolymerization of non‐homopolymerizable donor and acceptor monomers. The first one is based on the terminal model considering only the propagation reactions of the free monomers. The second one is the complex model considering only the reactions of charge‐transfer complexes. This paper describes a new kinetic scheme involving the participation of both the free monomers and the charge‐transfer complexes. Quantitative treatment of the overall polymerization rate by this new kinetic scheme allows to evaluate the degree of the participation of the free monomers and the charge‐transfer complexes. For the first time therefore it is possible to determine quantitatively the influence of charge‐transfer complexes on the free radical terpolymerization of non‐homopolymerizable monomers.

Discriminatory Photoactivation of Diastereomeric RAFT Agents

“…However, Ane is a non-homopolymerizable monomer with propagating rate to be nearly zero. A comonomer, N -phenyl­maleimide (PMI), is necessary to be used to copolymerize with Ane due to the possible formation of a charge transfer complex between Ane and PMI. ,,− Meanwhile, PMI is also regarded as a non-homopolymerizable monomer (propagation rate constant is very low). ,,,,, The final polymers therefore present alternating nature of PMI and Ane. Although the copolymerization might bring complicated propagation kinetics (reinitiation of polymer chain with two possible chain ends derived from Ane and PMI, diverse chain transfer, and termination), only the consumption of RAFT agents, Dia1 and Dia2, was monitored, which mostly involves the photoactivation of RAFT agents during initiation step and the activation caused by chain transfer.…”

Free radical terpolymerization of three non-homopolymerizable monomers, 2. Terpolymerization ofN-ethylmaleimide, anethol andtrans-stilbene

“…From the reaction scheme and under the approximations mentioned in the recent paper, [2] the overall polymerization rate (5 Br ) can be expressed as the sum of the reaction rates of the free monomers 5 p (f) and the CT complexes 5 p (CT): From the reaction scheme and under the approximations mentioned in the recent paper, [2] the overall polymerization rate (5 Br ) can be expressed as the sum of the reaction rates of the free monomers 5 p (f) and the CT complexes 5 p (CT):…”

“…The terpolymerization of these mono-mers can be considered according to the terminal model [1] or can formally be understood on the basis of the formation of charge-transfer complexes (CT complexes) between donor and acceptor monomers [1] A new kinetic treatment [2] allows to estimate the ratio of the participation of CT complexes and of free monomers in the free radical terpolymerization of non-homopolymerizable donor and acceptor monomers for the whole range of monomer composition. Terpolymerizations of electron-rich (donor) monomers and electron-accepting (acceptor) monomers result in terpolymers, with alternating sequences of donor and acceptor monomers.…”