Characterization of interfacial interactions in bamboo pulp fiber/high-density polyethylene composites treated by nano CaCO3 impregnation modification using fractal theory and dynamic mechanical analysis

Abstract

In order to study the relationship between the interfacial adhesion and preparation technology, nano CaCO3 impregnation modification (IM) as an efficient way was reported for improving the interfacial interactions, using three preparation technologies which include hot press molding (HPMP), extrusion molding (EMP) and injection molding process (IMP) to produce the bamboo pulp fiber (BPF) reinforced HDPE composites. Fractal theory and dynamic mechanical analysis were used to investigate the interfacial interactions quantificationally. The fractal dimension D of composites was different, indicating the D did characterize the difference among the different complicated fracture surfaces. A poor correlation (R2 = 0.4563) was observed between three preparation technologies and D, indicating there are remarkable difference between HPMP, EMP and IMP. The apparent activation energy was lower in the IM-BPF/HDPE composites (e.g. 115.99 kJ/mol for EMP-2 <124.88 kJ/mol for EMP-1). The least potential energy was needed to change the structure of the composites prepared by EMP, which indicated that the interfacial adhesion of composites prepared by EMP was the best while the HPMP was the worst. It can be concluded that IM had an interactive effect with preparation technology on interfacial interactions of the composites and IM worked more effectively on composites prepared by EMP.