Preparation and performance of wheat-straw composite board with inorganic adhesive

Abstract

With wheat-straw and inorganic binder as the major raw materials, inorganic wheat-straw composite board was manufactured by moldpressing. The effect of wheat-straw loading on the physical and mechanical properties of inorganic wheat-straw composite board was studied. X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were used to characterize and evaluate the performance of the resulting composite board. Results showed that the optimal glue-straw ratio was 2.1. With the increase in glue-straw ratio during board maintenance, the inhibition effect was weaker during hydration reaction of inorganic materials. This accelerated the process of the hydration reaction in inorganic wheat-straw composite board such that the reaction was carried out more completely and produced more complete crystallization and more inorganic glue. Internal bond strength (IB) and thermal stability of inorganic wheat-straw composite board increased gradually, while TS decreased. Modulus of rupture (MOR) and modulus of elasticity (MOE) firstly increased and then decreased. In summary, the bonding interface between wheat-straw and inorganic adhesive performed well.