Polymers oxazolidone containing

The synthesis and properties of 2-oxazolidones and 2-oxazolidone-containing polymers have been reviewed by Pankroatov et al (115). It is interesting to note that some isocyanate cyclotrimerization catalysts also act as catalysts for urethane, oxazolidone and/or carbodiimide linkages. 

Other special aliphatic imide forming compounds claimed in patents, like 2-oxazolidone [85] or epsilon-caprolactame, lead to polymers having aliphatic chains. These chains are responsible for the lower Tg of the cured films in comparison with the polymers having aromatic diamines. No commercial polyfes-ter-imide) wire enamel in western Europe contains them. 

The kinetics of ultrafast polymerization of acrylic monomers exposed to UV radiation or laser beams has been investigated by IR spectroscopy. An 8 fold increase of the cure speed was observed by using diphenoxybenzophenone as photoinitiator instead of benzophenone. llie reactivity of polyurethane-acrylate or epoxyacrylate systems was markedly improved by adding acrylic monomers that contain carbamate or oxazolidone groups and which impart both hardness and flexibility to the cured polymer. Time-resolved infirared spectroscopy was used to directly record the actual polymerization profile for reactions taking place within a fraction of a second upon UV or laser exposure. Comparison with other techniques of real-time analysis show the distinct advantages of this method for an accurate evaluation of the important kinetic parameters and of the dark polymerization which develops just after the irradiation. 

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