Mechanical and microstructural properties of redispersible polymer-gypsum composites

Studies on gypsum modified by polymers have been conducted to assess the potential of improvement in the mechanical performance, water resistance and increasing the setting time, facilitating its handling. Gypsum-based compounds made with different additions of redispersible polymers were studied, such as: ethylene-vinyl acetate (EVA), vinyl acetate terpolymer, vinyl laurate and vinyl chloride (VA/VL/VC), and vinyl acetate and vinyl versatate (VA/VeoVA). The influence on setting time, microstructural formation and on the bending performance was assessed, as well as and compression of the hardened gypsum. The composites were prepared using a polymer concentration of 5% and 10%, and water/gypsum ratio of 0.6. The addition of the polymer decreased the structural robustness and change in the microstructure. We concluded that the reduction in the amount of water through additives may allow a more complete and robust training of gypsum crystals and compounds with better mechanical performance223COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESnão te

Brazilian University Students: Predictors Of Seeking Mental Health Care For A Second Time [estudantes Universitários Brasileiros: Preditores De Uma Segunda Busca Por Atendimento Em Saúde Mental]

[No abstract available]1293181182Oliveira, M.L., Dantas, C.R., Azevedo, R.C., Banzato, C.E., Demographics and complaints of uni-versity students who sought help at a campus mental health service between 1987 and 2004 (2008) Sao Paulo Med J, 126 (1), pp. 58-6