PHOTOCALORIMETRIC MONITORING OF THE POLYMERIZATION OF AN OLIGO(ETHYLENE GLYCOL) DIMETHACRYLATE IN OLIGO(ETHYLENE GLYCOL) DIMETHYL ETHERS

The course of the 2,4,6-trimethylbenzoyldiphenylphosphine oxide initia ted free-radical photopolymerization of an oligo(ethylene glycol) dime thacrylate ((EG)(23)DMA) in two oligo(ethylene glycol) dimethyl ethers ((EG)(3)DME and (EG)(11)DME) in the presence of LiCF3SO3 has been stu died by means of differential scanning calorimetry (DSC), FT-Raman spe ctroscopy and sol-gel analysis. In order to obtain the kinetical data of the fast photopolymerization, the photo-DSC curves were corrected n umerically. Both, the initial and the maximum polymerization rates wer e found to depend on the concentration of the monomer and the photo-in itiator with the order 2,5 and 0,2, respectively. Upon addition of LiC F3SO3, the polymerization rate is increased. Grafting reactions from ( EG)(11)DME were observed resulting in its partially linking to the pol y(methacrylate) network.