Improving lignocellulose thermal stability by chemical modification with boric acid for incorporating into polyamide

The preparation of bio-composites based on engineering plastic is always restricted by the low thermal stability of lignocellulose. In this study, the thermal stability of lignocellulose was improved by boric acid modification. Then, the borated lignocellulose was characterized to analyze the mechanism of involved in the improvement of thermal stability. Furthermore, the untreated and borated lignocellulose was combined with polyamide 6 to produce bio-composites. The effects of lignocellulose content and boric acid modification on the color, thermal stability and mechanical properties of the resulting composites were compared and analyzed. Boric acid protected lignocellulose from thermal degradation, increasing the lightness of the resulting composites. However, boric acid appeared to have a negative effect on the mechanical strength of the resulting composites. In summary, this study demonstrated that bio-composites based on engineering plastic could be prepared by improving the thermal stability of lignocellulose using a boric acid treatment. (C) 2020 The Authors. Published by Elsevier Ltd.