Copolymerization with depropagation: A study of α‐methyl styrene/methyl methacrylate in solution at elevated temperatures

Abstract

In free-radical polymerization, solvents are routinely used to reduce the solution viscosity and molecular weight. In the case of the ␣-methyl styrene/methyl methacrylate copolymer system, reducing the monomer concentration also has significant effects on the copolymer composition and maximum conversion obtained. Reactivity-ratio studies as well as full-conversion-range data were provided, and the results were compared to similar data in the bulk phase from our earlier work. A 30 wt % toluene solution was used for all experimental conditions. Copolymer composition modeling results were also presented.

Melt grafting of maleic anhydride onto polypropylene with assistance of α‐methylstyrene

“…Because the free radical polymerization of AMS has a ceiling temperature of 61°C in bulk and a high chain transfer constant to monomer, it gives low monomer conversion and molecular weight under conventional bulk conditions [16–18]. However, recent researches indicate that the copolymerization of AMS with other monomers can get favorable kinetics [18–22].…”

Comparative Trends of Copolymerizations Involving Alpha Methyl Styrene at Elevated Temperatures 1*

“…Neither temperature nor initial feed composition has much effect on the cumulative copolymer composition. [5,6] In the MMA/AMS system this phenomenon is observed at various different feed levels, temperatures and even after It was also found that solvent dilution had little effect on polymer composition for the feeds studied.…”

“…[7] At all temperatures the data collected for solution copolymerizations were the same as those for bulk experiments at given monomer feed ratios. The MMA/AMS copolymerization showed the most extreme behaviour in terms of how depropagation can affect the product composition in low conversion copolymerizations (Palmer et al [5,6] ). This was not observed, again indicating that the effects of depropagation at low conversions are not significant.…”

“…[5,6] Notably, the equilibrium conversion level shows a significant dependence on reaction temperature. [5,6] Notably, the equilibrium conversion level shows a significant dependence on reaction temperature.…”

“…Results from low conversion studies (reactivity ratio estimation) and full conversion range studies in bulk and solution were collected and presented previously in Dube et al, [1,2] Hakim et al, [3] McManus et al, [4] Palmer et al, [5,6] and Wang. Results from low conversion studies (reactivity ratio estimation) and full conversion range studies in bulk and solution were collected and presented previously in Dube et al, [1,2] Hakim et al, [3] McManus et al, [4] Palmer et al, [5,6] and Wang.…”