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In this study, 2‐hydroxyethyl acrylate (HEA) was polymerized to obtain polymers that can be used as hydrogel and copolymerized for biomedical applications. Bulk, solution, and atom transfer radical polymerization (ATRP) techniques at different temperatures were applied. The polymerization in bulk form was carried out in vacuum and in open atmosphere. The polymerization curves showed autoacceleration mechanism and the limiting conversion was 100%. The polymers obtained were insoluable in most common solvents because of high molecular weights and strong intermolecular hydrogen bonding. They absorb more than 30% (w/w) water as hydrogel. To decrease the molecular weight and obtain soluble polymers, HEA was polymerized in solution by ATRP method, which also gave insoluble hydrogel type polymers. The activation energy for bulk polymerization was 155.8 kJ/mol, which is very high for a free radical polymerization. This is due to the high degree of intermolecular hydrogen bonding, which was also supported by FTIR and TGA analysis. The polymers were characterized by FT‐IR, DSC, TGA, and 1H NMR techniques. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3957–3965, 2005

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The aim of this study was to determine the effect of autoclave polymerization on the transverse strength of denture base polymers. To this end, 30 rectangular test specimens were fabricated of two heat-polymerized denture base polymers. The test groups were: (I) control, i.e., conventional water bath to polymerize resins by heat at 100°C for 30 minutes; (II) autoclave polymerization at 60°C for 30 minutes followed by 130°C for 10 minutes; and (III) autoclave polymerization at 60°C for 30 minutes followed by 130°C for 20 minutes. The specimens were tested with three-point bending test at a crosshead speed of 5 mm/min. It was revealed that the transverse strength of specimens increased with statistical significance when the autoclave was used for polymerization.