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Kinetics of copolymerization

1979; Wiley; Volume: 3; Issue: S19791 Linguagem: Inglês

10.1002/macp.1979.020031979107

0025-116X

P. Wittmer,

Thermal and Kinetic Analysis

In comparison to the number of publications on composition and structure of copolymers, there are only a few publications on the kinetics of radical copolymerizations. The equation by Melville and Walling is a first attempt to describe the kinetics. It was derived using the assumption that termination is chemically controlled. Since the 1960s it has been realized that in the case of radical polymerization reactions the chain termination is controlled by diffusion. Based on this knowledge Atherton and North developed a rate equation from which a termination constant can be ascertained from each monomer mixture composition. Russo and Munari continued North's works. They showed that the copolymerization rate can be adequately described if one assumes that the last two monomer units in the chain radical determine its segment flexibility. Apart from the constants known from the corresponding homopolymerizations the equation of Russo and Munari contains two other parameters, which are linearly connected. This equation was used in a discussion on copolymerization reactions in a homogeneous continuously stirred tank reactor (HCSTR). In this context the attainment of the steady state after disturbing input and output of the reactor was investigated.