Effect of silane treatment on mechanical properties and thermal behavior of bamboo fibers reinforced polypropylene composites

Qianting Wang,Jianjie Wang,Weikang Liang,Youxin Chen,Yu Zhang

doi:10.1177/1558925020958195

Abstract

In this work, the surface of the bamboo fibers (BF) was treated with three kinds of silane coupling agents terminated with amino functional groups (KH550), epoxy functional groups (KH560), and methyl functional groups (KH570) to improve fiber–matrix adhesion. The effects of silane treatment on the mechanical properties and thermal behavior of BF/polypropylene (PP) composites were investigated. Mechanical test results showed that the order of modification effectiveness was KH570 > KH550 > KH560. KH570 treated fiber composite exhibited the best mechanical properties. The tensile strength and flexural strength of 5 wt% KH570 treatment reached to 36.1 and 54.7 MPa, which were 15.4% and 23.6% higher than those of UBF/PP composites. Simultaneously, the thermal stability increased from 467.0°C (UBF) to 470.6°C (KH-570 treated BF). An increase in crystallization temperature (1.7°C) and a decrease in crystallinity (5.8%) occurred upon the addition of 5% KH570 silanes treated bamboo fibers.

Highlights

With the depletion of non-renewable petroleum-based materials and the increasing environmental pollution, natural plant-fibers-reinforced composites have received extensive attention as an environmentally friendly material
It was found that silane treatment of fibers improved the mechanical properties of composites compared with untreated and alkali treated fiber composites
The main objective of the investigation was to study the influence of three types of silane coupling agents on mechanical properties, thermal properties and interfacial properties of the resulting bamboo fibers (BF)/PP composites

Summary

Introduction

With the depletion of non-renewable petroleum-based materials (such as plastic) and the increasing environmental pollution, natural plant-fibers-reinforced composites have received extensive attention as an environmentally friendly material. Sepe et al.[28] studied the effects of alkali and silane treatment on mechanical properties of woven hemp fiber reinforced epoxy composites. It was found that silane treatment of fibers improved the mechanical properties of composites compared with untreated and alkali treated fiber composites. The bamboo fibers were selected as reinforcement to enhance PP due to bamboo fibers’ specific properties such as low density, specific strength, and stiffness.[29] The main objective of the investigation was to study the influence of three types of silane coupling agents on mechanical properties, thermal properties and interfacial properties of the resulting BF/PP composites. The bamboo fibers were chopped into 3 to 6 mm in length and washed with deionized water for several times to remove surface impurities.

Results and discussion

Conclusion

31. ISO 527