Produção de compósito do tipo gesso-polímero para aplicação na fabricação de painés externos em edificações

Abstract

The Plaster Pole of Araripe localization is more than privileged. Situated in the state of Pernambuco high hinterlands, about 800 km equidistant of 8 Brazilian capitals (Recife, Salvador, Fortaleza, Aracaju, Maceió, João Pessoa, Natal and Teresina), it generates 13,200 direct jobs and 66,000 indirect jobs, making an important center for social- economic activities out of the Plaster Pole of Araripe on the Northeast of the country. In Brazil, traditional methods of production and building are gradually being replaced by industrialized construction systems. This study aimed to develop a production process for obtaining a new type of composite plaster-polymer with high mechanical strength and humidity resistance. Considering that purposes were investigated: temperature, pressure and timing needed to obtain a composite which would make an external coating material out of plaster, such material would be hydrophobic and with reduced production of solid waste during transport and application. The monomer used for the experimental tests was the styrene for the availability of it on the market. The composite produced was obtained by bulk polymerization of styrene in samples pre-cast in plaster. Following a central composite design (CCRD) were performed 20 experiments distributed in complete factorial, six central points and six axial points. The response variables were the tensile strength in bending, compression, water absorption and polymer conversion. The minimum water absorption (1.03%) and maximum tensile strength in bending (9.89 MPa) and compression (24.80 MPa), those chracteristics of the composite plaster-polymer showed themselves superior to the values found on the pure plaster, allowing the usage of this composite in external panels, enabling also a considerable reduction of solid waste on the handling of this material