Original scientific paper
Effect of Heating Rate on Glass Transition of a Cross-linked Denture Base Resin
Vjekoslav Jerolimov
; Department of Removable Prosthodontics, School of Dental Medicine University of Zagreb, and Clinical Department of Prosthodontics, Dubrava Clinical Hospital, 10000 Zagreb, Croatia
Robert G. Jagger
; Department of Restorative Dentistry, University of Wales College of Medicine, Cardiff, Wales, UK
Paul J. Millward
; Department of Restorative Dentistry, University of Wales College of Medicine, Cardiff, Wales, UK
Vlado Carek
; Department of Removable Prosthodontics, School of Dental Medicine University of Zagreb, and Clinical Department of Prosthodontics, Dubrava Clinical Hospital, 10000 Zagreb, Croatia
Abstract
The purpose of the study was to investigate the effect of different heating rates in the evaluation of the transition glass temperature of a dough-moulded poly(methylmethacrylate) denture base material Cross-linking agent ethylene glycol dimethacrylate (EGDMA) was added to the MM A monomer component: in concentration of 10% by volume. The polymer component was an unpigmented PMMA homopolymer. A comparison group of specimens was made by use of monomer liquid without any cross-linking agent. Specimens were produced in moulds according to conventional dental flasking and curing procedures. Measurements of Tg were determined by thermomechanical analysis using a Stanton Redcroft TMA, Model 790 (PL Thermal Science Ltd., Epson, UK). Heating rates of 5 °C/min, 10 °C/min and 15 °C/min were selected for this investigation. It was concluded that the addition of cro- os-linking agent would affect Tg denture base resins. Tg values were highly dependent on the heating rates used in thermomechanical analysis, being very significantly increased with a heating rate increase.
Keywords
denture base acrylic resins; cross linking; glass transition temperature; heating rate
Hrčak ID:
98643
URI
Publication date:
15.12.1996.
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