Thermo-Mechanical and Morphological Properties of Water Hyacinth Reinforced Polypropylene Composites

Manabendra Saha,Ali Md Afsar

doi:10.26776/ijemm.03.03.2018.04

Manabendra Saha, Ali Md Afsar

Open Access

https://doi.org/10.26776/ijemm.03.03.2018.04

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Abstract

This paper focusses on the analysis of thermo-mechanical and morphological properties of water hyacinth (WH) fiber reinforced polypropylene (PP) biocomposites manufactured by using a single screw extruder and an injection molding machine. With a view to increasing the compatibility between the WH fibers and polypropylene matrix, raw WH fibers were chemically treated with Benzenediazonium salt in base media. Composites were manufactured with five different levels of loading (15, 20, 25, 30 and 35 wt%) of both the raw and treated WH fibers. Thermal properties of WH-PP composites were evaluated by thermogravimetric and differential thermal analyses. To analyze mechanical properties of composites, tests of tensile strength and stiffness, flexural strength and stiffness, and Charpy impact strength were carried out following ASTM standards. It was found that thermal stability and all the mechanical properties except tensile strength were improved considerably for chemically treated WH fiber composites in comparison with untreated ones. Fracture surfaces of the tensile and flexural specimens were scanned with scanning electron microscopy (SEM) to understand their surface morphologies. The SEM images clearly revealed that there were fewer fiber agglomerations, microvoids, and fiber pull out traces in treated WH-PP composites than in the untreated ones indicating better distribution of the fibers into the matrix as well as stronger fiber matrix interfacial adhesion due to treatment of WH fibers. Water absorption properties were studied to evaluate the viability of these biocomposites under specified conditions.

Highlights

Natural fiber reinforced polymer matrix composites, often called biocomposites, are preferred over artificial fiber reinforced composites as natural fiber composites have outstanding advantages of environment friendliness, biodegradability, recyclability, cost-effectiveness, and better physico-mechanical properties [1,2,3,4,5,6]
The curve corresponding to Benzenediazonium salt (NNDMA)/NaOH treated water hyacinth (WH)-PP composite exhibits single peak at 469 ̊C temperature while the raw WH-PP composite exhibits the peak at 462 ̊C temperature
These results show that Benzenediazonium salt, (Anl)/NaOH, treated WH-PP composites exhibit more thermal stability than those of Benzenediazonium salt, (NNDMA)/NaOH, treated WH-PP composites and raw WH-PP composites in terms of the highest final decomposition temperature and largest amount of residual mass

Summary

Introduction

Natural fiber reinforced polymer matrix composites, often called biocomposites, are preferred over artificial fiber reinforced composites as natural fiber composites have outstanding advantages of environment friendliness, biodegradability, recyclability, cost-effectiveness, and better physico-mechanical properties [1,2,3,4,5,6]. 2.2 Chemical Treatment of WH Fiber In an attempt to improve mechanical properties of the composites, WH fibers were chemically treated using benzenediazonium salt. In order to increase the compatibility of the WH fibers with PP matrix, raw WH fibers were chemically treated with (Anl)/NaOH and (NNDMA)/NaOH.

Results

Conclusion