Influence of polymerization cycle in properties of acrylic resin polymerized by microwave energy

  • Fabrício Mezzomo Collares Universidade Federal do Rio Grande do Sul
  • Carmen Beatriz Borges Fortes Universidade Federal do Rio Grande do Sul
  • Vicente Castelo Branco Leitune Universidade Federal do Rio Grande do Sul
  • Stefani Becker Rodrigues Universidade Federal do Rio Grande do Sul
  • Susana Maria Werner Samuel Universidade Federal do Rio Grande do Sul
  • César Petzhold Universidade Federal do Rio Grande do Sul
  • Vater Stefani Universidade Federal do rio Grande do Sul
Keywords: Acrylic resins, Microwaves, Hardness test, Solubility


Objective: The purpose of this study was to evaluate the physicochemical properties of acrylic resin polymerized by microwave energy in short cycle of polymerization.
Methods: Two brands (Classico and VIPI) and two cycles were evaluated (manufacturer cycle and short cycle). The characteristics and properties as degree of conversion, glass transition temperature, impact strength-Izod, Knoop hardness, swelling degree, soluble fraction, specific mass, water sorption and solubility were evaluated.
Results: Glass transition temperature, hardness, specific mass, soluble fraction and solubility were statistically significant between cycles and brands (p<0.05). Water sorption showed no difference between cycles (p>0.05) and impact strength presented difference between brands in short cycle (p<0.05). Acrylic resin polymerized by microwave energy with manufacturer cycle presented no difference in physicochemical properties between evaluated brands. Conclusion: The short cycle of polymerization showed reduced properties in microwave acrylic resin when compared to manufacturer cycle. Manufacturer cycle of polymerization should be used to acrylic resin devices production.


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Original Article