Multi-user equipment approved in grant 2013/50897-7: cylindrical and horizontal autoclave

Abstract

The objective of this proposal is to develop a new technology using an environment with excess of CO2 for curing of the fiber-cement products reinforced with cellulose and synthetic fibers, mainly roofing tiles. Cellulosic fibers are adequate for production of thin components, even for optimization of the fabrication process, and as reinforcement. However, the synthetic fibers, normally used in association with cellulose pulps, are very expensive, increasing the cost of the final product. Furthermore, there are some problems with the dimensional stability of the fiber-cement products, such as the fissures caused by the drying shrinkage. The present technology intends to gradually diminish the use of synthetic fibers and then decrease drastically the costs of raw materials in the asbestos-free fiber-cement formulations. The partnership collaboration between university (USP) and national private companies (Infibra and Imbralit) is an answer for the demand for new processes and fiber-cement products, adequate to the Brazilian consume of roofing materials, façades, cladding and "dry wall" systems. It is also an initiative for labor training in the way for expansion of the fiber-cement market in Brazil. The main steps of this project are: (i) the benchmarking; (ii) the development of a new curing process (in pilot scale) and analysis of the physical-mechanical properties; (iii) the re-formulation of the composite, by the selection and adjusting of the fibers and cementitious matrix in each partner company (Infibra and Imbralit); (iv) the determination of the chemical and microstructural properties of the new material and characterization of its performance in relation to the technical standards of the sector; and (v) the study of the durability and stability of the fiber-cement at the long term (simulating the exposition to weathering). (AU)