Thermal properties and aging characteristics of chemically modified oil palm ash-filled natural rubber composites

摘要

The chemically modified oil palm ash (OPA) with the cetyltrimethylammonium bromide (CTAB) solution was prepared prior to compounding with the natural rubber and other curing ingredients. The aging resistance and thermal stability of CTAB-modified OPA-filled natural rubber composites were evaluated in the same manner as non-modified OPA samples. The retention tensile properties after thermal aging was measured and based on the result shown, the CTAB-modified OPA-filled natural rubber composites imparted insignificant effect to aging resistance as compared to the non-modified OPA-filled natural rubber composites at very low OPA loading; however, the effect became apparent beyond 3 phr OPA loading where the CTAB-modified OPA-filled natural rubber composites provided better aging resistance than the corresponding non-modified OPA-filled natural rubber composites. The thermogravimetric analysis indicated that the CTAB-modified OPA-filled natural rubber composites exhibited lower thermal stability which showed lower temperature at their respective weight loss and lesser char residue than that of non-modified OPA-filled natural rubber composites. This was attributed to the CTAB which started to decompose at the temperature of 210℃. However, for the range from ambient temperature to 210℃, the CTAB-modified OPA-filled natural rubber composites produce better thermal stability than those of non-modified OPA-filled natural rubber composites.