Effect of Hot-Alkali Treatment on the Structure Composition of Jute Fabrics and Mechanical Properties of Laminated Composites.

Xue Wang,Lulu Chang,Xiaolong Shi,Lihai Wang

doi:10.3390/ma12091386

Abstract

In this study, jute fabrics/epoxy-laminated composites were fabricated via a simple and effective manual layering. Hot-alkali treatment was used to pretreat jute fabrics to improve their interfacial compatibility. The effects of hot-alkali treatment with five concentrations (2%, 4%, 6%, 8% and 10%) on the composition, crystallinity and surface morphology of jute fibers, were analyzed with the aids of Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), and the scanning electron microscope (SEM). The mechanical properties (tensile and flexural) of laminated composites, and the morphology of the tensile fracture surface, were analyzed. The results indicated that the crystallinity index (CI) and crystallite size (CS) of the cellulose in jute fibers were improved, and there were three stages for CI and CS with the increase of alkali concentrations. Hot-alkali treatment improved the mechanical properties of laminated composites, especially for the 6% NaOH-treated jute fabric reinforced. The tensile strength, flexural strength, tensile modulus and flexural modulus of 6% NaOH-treated fabrics reinforced composites were enhanced by 37.5%, 72.3%, 23.2% and 72.2%, respectively, as compared with those of untreated fabrics reinforced composites. The fiber pull-out and the gaps of the tensile fracture surface were reduced after hot-alkali treatment.

Highlights

With the increasing depletion of petroleum resources, the development and utilization of new environment-friendly structural and functional materials has become imperative [1,2,3,4].Nowadays, the environmental protection materials are advocated
The hydroxyl groups are present in the main components of the jute fiber, and bond together in the form of intermolecular hydrogen bonds or intramolecular hydrogen bonds
The reason is that absorption peak at 1735 cm−1 is the C=O stretching vibration of the carboxylic acid in hemicellulose of untreated jute fibers [28,30]

Summary

Introduction

With the increasing depletion of petroleum resources, the development and utilization of new environment-friendly structural and functional materials has become imperative [1,2,3,4].Nowadays, the environmental protection materials are advocated. The laminated composite is one of them It is the superposition of fibers (carbon fibers, glass fibers [5] or plant fibers) and resin, by imitating the physiological structure of nacre (Mother of Pearl) layers. Some natural biological materials have excellent matching in structure and function, such as bamboo, wood, bones, natural fibers, nacre and others [6,7]. The nacre layers in a shell are natural laminated composites. Organic layers and aragonite crystals are the matrix and reinforcements of the natural laminated composites, respectively. Their combination gives a shell its high strength and toughness [10]. Scholars have enlightened the structure of organic-aragonite-organic in nacre to prepare the matrix-fabric-matrix laminated composites

Methods

Results

Conclusion