Effect of glycerol concentration and of the solvent composition on the degradation of cellulose acetate membranes to be used in periodontal regeneration techniques
de Melo Patricia Gontijo (1), Ferreira Jéssica Afonso (2), da Silva Ingrid Souza Vieira (1), Demonari Eric Guidetti (1), Ruggiero Reinaldo (1)*
(1) Institute of Chemistry, Federal University of Uberlândia - Uberlândia, Minas Gerais. - Brazil, (2) Dentistry School, Federal University of Uberlândia - Uberlândia, Minas Gerais. - Brazil
Ten membranes of cellulose acetate, prepared by the casting method, from the dissolution of commercial acetate having DS = 2.2, in two different solvents (pure acetone and acetone / water (80:20 v / v)), after be doped with different concentrations of glycerol as plasticizer, were allowed to degrade immersed in phosphate buffer (pH 7.2) at controlled temperature (36.5 ± 0.1 ° C), conditions simulating the human body blood. The degradation monitored by spectroscopy in the UV / Visible region, showed that glycerol at a concentration of 10% w / w served as reinforce for the membranes, as confirmed by the total degradation time and for thermal and thermo-mechanical analysis measures. The results also shown that the presence of water in the solvent mixture, acted as a second plasticizer, altering the degradation process, and important properties of the membranes such as, porosity, permeability to water vapor, crystallinity, contact angle and storage/loss modules.