Influence of chemical additive on the physical and mechanical properties of cement-bonded composite panels made from jute stick

Abstract

The aim of the study was to observe the effects of chemical additives (calcium chloride (CaCl2) and magnesium chloride (MgCl2)) on the setting time of jute stick cement-bonded composites (CBCs). The setting time was judged based on the measured physical and mechanical properties of the composites as function of the press time. The mixing ratio of jute stick particles, cement and water was set at 2:1:1 for chemical additive (CaCl2/MgCl2) incorporated composites, and a controlled one without additive was manufactured based on jute particles and cement mixing ratio of 2:1. Three concentration levels of 6, 8 and 10% of CaCl2 and MgCl2 were used separately to produce the composite boards. In this study, the composite mixtures were cold-pressed at a pressure of 5 MPa and different pressing duration of 4, 6, 8, 12 and 16 h. Incorporation of the additives reduced the press time, and higher percentage of additives increased the physical and mechanical properties of the composite panels produced. Composite panels made with MgCl2 exhibited better performance compared with those made with CaCl2. The highest modulus of elasticity (MOE) and modulus of rupture (MOR) of the manufactured samples were 10.5 and 4595 MPa, respectively for the maximum percentage of MgCl2 addition with 6 h press time. It appears that these additives especially MgCl2 decreased the setting time of the CBCs, which can be considered as an alternative approach for the industry to produce CBCs in shorter time.