EFFECT OF CHEMICAL-STRUCTURE OF ALLYL ETHERS ON POLYMERIZATION AND PROPERTIES OF MULTIFUNCTIONAL ACRYLATE SYSTEMS

Allyl ether resins with various chemical structures and degrees of functionality were used as promoters and cross-linkers for polymerization of acrylic oligomers at room temperature in air. Thin films were prepared to allow monitoring of polymerization via disappearance of acrylate and allylic unsaturation by FTIR. The effect of air upon curing of films was investigated; excluding air from the surface of the film had a much greater effect than did addition of allyl ether. In air, the curing rate and extent of cure were found to be dependent upon molecular weight M(n) and degree of functionality of the allyl compounds. At high allyl monomer concentrations, homopolymerization of the allyl groups occurred. The mechanical properties (tensile strength, Young's modulus, and elongation at break) of films were evaluated on an Instron, whereas viscoelastic properties, transition temperatures, and cross-link densities of polymer bars were studied by dynamic mechanical analysis and relaxation measurements. The study showed that addition of highly functional allyl ethers combines the advantages of an air-curable system with those of highly cross-linked materials, allowing ultimate properties to be tailored.