Optimization of processing variables and mechanical properties in rubber-wood particles reinforced cement based composites manufacturing technology

Abstract

The manufacturing processes of rubber crumb–wood particle reinforced cement based composites (RWCC) which shortened the pressing cycle and enhanced the properties were completely investigated. Meanwhile, optimal processing conditions as well as properties of strength were tested to validate the predicted variables and properties. Mechanism effects of interacting process variables [density, duration of pressure time (namely, pressure time) and pressure] on properties of RWCC were opened out. The RWCC performance was evaluated by measuring its flexural strength (FS), modulus of elasticity (MOE) and internal bond (IB) strength. The experimental results were statistically analyzed by using Response Surface Method (RSM) software to identify the significant manufacturing process variables for RWCC. In the process variables, density and duration of pressing time had more significant influences on mechanical properties (FS and MOE and IB), but had little effect on strength performance caused by pressure. In addition, the microstructure of RWCC was clearly examined by using a scanning electron microscope (SEM). The mechanism effects were also revealed through analyzing the microstructure of the interface of rubber crumb/wood particle/cement. The results of a comprehensive evaluation for properties of RWCC with the highly active polymeric methylene diphenyl isocyanate adhesive (PMDI) as binder system not only present excellent mechanical properties, but also possess some of functional properties such as optimized acoustic properties and energy conservation. Finally, the optimal manufacturing process parameters were obtained by means of the maximizing mechanical properties.