Bulk copolymerization of dimethyl meta-isopropenyl benzyl isocyanate (TMI®): Determination of reactivity ratios

✍ Scribed by S. Mohammed; E. S. Daniels; A. Klein; M. S. El-Aasser

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 184 KB
• Volume: 67
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19980118)67:3<559::aid-app18>3.0.co;2-q

✦ Synopsis

Dimethyl meta-isopropenyl benzyl isocyanate (TMI) is a bifunctional monomer with an unsaturation and an isocyanate group. Bulk copolymerizations of TMI with styrene, methyl methacrylate, and n-butyl acrylate were investigated. Polymerizations were carried out to low conversions in sealed test tubes at 70ЊC. The copolymer composition was determined using Fourier transform infrared (FTIR) spectroscopy. The data were analyzed using the terminal, as well as restricted penultimate, model of copolymerization. The method of Kelen-Tudos was used to calculate the reactivity ratios according to the terminal model. A nonlinear regression analysis was also carried out. Low reactivity ratio values for TMI were obtained for the copolymerizations with styrene and methyl methacrylate as a result of the inability of TMI to undergo homopolymerization. The value was higher for the copolymerization with nbutyl acrylate. Composition diagrams were generated, and the range of TMI concentration in the monomer charge for the preferential incorporation of TMI in the copolymer was identified.