Effect of composition on the gelation of tissue conditioners.
Tissue conditioners comprise poly(ethyl methacrylate) powder (or related copolymer) and a liquid containing a plasticizer and ethanol. Gelation times for two butyl/ethyl copolymers and one poly(ethyl methacrylate) polymer with buty phthalyl butyl glycollate or di-2-ethyl hexyl maleate and varying amounts of ethanol have been measured in the range 20-40 degrees C. The proprietary material "Viscogel" was used as a standard. Results were plotted according to the Arrhenius equation enabling activation energies to be determined. Values for activation energies ranged from 55 to 110 KJ mol-1 K-1. The 60/40 butyl/ethyl methacrylate copolymer gave the lowest values and those containing poly(ethyl methacrylate) the highest.
Parker
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S
Department of Biomateials in Relation to Dentistry, London Hospital Medical College, UK.
Braden
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M
D001672:Biocompatible Materials; D000431:Ethanol; D005782:Gels; D008768:Methylmethacrylates / Q000737:chemistry*; D010968:Plasticizers; D013329:Structure-Activity Relationship; D013816:Thermodynamics; D013997:Time Factors
D001672:Biocompatible Materials; D005782:Gels; D008768:Methylmethacrylates; D010968:Plasticizers; D000431:Ethanol; C009931:poly(ethylmethacrylate)