Bulk polymerization and characterization of isocyanatoacrylate copolymers

The purpose of this investigation was to prepare by bulk polymerization six new isocyanatoacrylate copolymers and to characterize them. The isocyanato acrylate copolymers, which were prepared by tri-n-butylborane oxide (TBBO)- initiated free-radical polymerization, were formed from 1 : 1 mol mixtures of 2-isocyanatoethyl methacrylate (IEM) with 2-hydroxyethyl methacrylate (H EMA), hydroxypropyl methacrylate (HPMA), 2-hydroxyethyl thiomethacrylate (H ETMA), ethylthioethyl methacrylate (ETEMA), 2-(acetoxyacetoxy)ethyl methacr ylate (AAEMA), and tetrahydrofurfuryl methacrylate (THFMA). These six copol ymers were compared to the homopolymer of IEM, which was polymerized in an identical fashion. The bulk polymers were fractionated into their acetone-s oluble and acetone-insoluble components. Physical characterization via phot oacoustic infrared (PASIR) spectroscopy showed vast differences in residual isocyanate content. Differential scanning calorimetry (DSC) thermal analys is was carried out on all polymers. Elemental analysis (nitrogen) determine d the ratio of IEM to the comonomer and boron analysis showed whether the i nitiator stayed in the acetone-insoluble fraction or was "extracted" into t he acetone-soluble fraction. In conclusion, we found that the composition o f the copolymers correlated well with the predicted design. (C) 1999 John W iley & Sons, Inc.