VISIBLE-LIGHT PULSED-LASER POLYMERIZATION AT 532 NM EMPLOYING A JULOLIDINE DYE PHOTOSENSITIZER INITIATION SYSTEM

The free-radical propagation rate coefficient of methyl methacrylate h as been measured using a new version of pulsed-laser polymerization em ploying a visible light wavelength (532 nm) generated by a frequency-d oubled Nd:YAG laser. The initiation system adopted was made up from ro phenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole), mercaptobenzoxazole, and nzo-[i,j]quinolizin-1-yl)methylene]cyclopentanone. The propagation rate coefficients obtained were consistent with values recommended as benchmark values by an IUPAC working party, A series of consistency c hecks was performed to ensure the validity of the experimental approac h. The experimental technique described in this paper extends the puls ed-laser polymerization method to a whole new range of UV-absorbing mo nomers that were previously inaccessible to study.