Biocomposites reinforced with natural fibers: 2000–2010

Studies on the use of natural fibers as replacement to man-made fiber in fiber-reinforced composites have increased and opened up further industrial possibilities. Natural fibers have the advantages of low density, low cost, and biodegradability. However, the main disadvantages of natural fibers in composites are the poor compatibility between fiber and matrix and the relative high moisture sorption. Therefore, chemical treatments are considered in modifying the fiber surface properties. In this paper, the different chemical modifications on natural fibers for use in natural fiber-reinforced composites are reviewed. Chemical treatments including alkali, silane, acetylation, benzoylation, acrylation, maleated coupling agents, isocyanates, permanganate and others are discussed. The chemical treatment of fiber aimed at improving the adhesion between the fiber surface and the polymer matrix may not only modify the fiber surface but also increase fiber strength. Water absorption of composites is reduced and their mechanical properties are improved.

Chemical Treatments of Natural Fiber for Use in Natural Fiber-Reinforced Composites: A Review

In recent years, natural fibers reinforced composites have received much attention because of their lightweight, nonabrasive, combustible, nontoxic, low cost and biodegradable properties. Among the various natural fibers; flax, bamboo, sisal, hemp, ramie, jute, and wood fibers are of particular interest. A lot of research work has been performed all over the world on the use of natural fibers as a reinforcing material for the preparation of various types of composites. However, lack of good interfacial adhesion, low melting point, and poor resistance towards moisture make the use of natural fiber reinforced composites less attractive. Pretreatments of the natural fiber can clean the fiber surface, chemically modify the surface, stop the moisture absorption process, and increase the surface roughness. Among the various pretreatment techniques, graft copolymerization and plasma treatment are the best methods for surface modification of natural fibers. Graft copolymers of natural fibers with vinyl monomers provide better adhesion between matrix and fiber. In the present article, the use of pretreated natural fibers in polymer matrix-based composites has been reviewed. Effect of surface modification of natural fibers on the properties of fibers and fiber reinforced polymer composites has also been discussed. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers

Pretreatments of Natural Fibers and their Application as Reinforcing Material in Polymer Composites—A Review

This paper provides a comprehensive overview on different surface treatments applied to natural fibres for advanced composites applications. In practice, the major drawbacks of using natural fibres are their high degree of moisture absorption and poor dimensional stability. The primary objective of surface treatments on natural fibres is to maximize the bonding strength so as the stress transferability in the composites. The overall mechanical properties of natural fibre reinforced polymer composites are highly dependent on the morphology, aspect ratio, hydrophilic tendency and dimensional stability of the fibres used. The effects of different chemical treatments on cellulosic fibres that are used as reinforcements for thermoset and thermoplastics are studied. The chemical sources for the treatments include alkali, silane, acetylation, benzoylation, acrylation and acrylonitrile grafting, maleated coupling agents, permanganate, peroxide, isocyanate, stearic acid, sodium chlorite, triazine, fatty acid derivate (oleoyl chloride) and fungal. The significance of chemically-treated natural fibres is seen through the improvement of mechanical strength and dimensional stability of resultant composites as compared with a pristine sample.

Chemical treatments on plant-based natural fibre reinforced polymer composites: An overview

Cellulosic/synthetic fibre reinforced polymer hybrid composites: A review

A comparison of the mechanical properties of phenol formaldehyde composites reinforced with banana fibres and glass fibres

Oil palm fibres have been used as reinforcement in phenol formaldehyde resin. In order to improve the interfacial properties, the fibres were subjected to different chemical modifications such as mercerisation, acrylonitrile grafting, acrylation, latex coating, permanganate treatment, acetylation, and peroxide treatment. The effect of fibre coating on the interface properties has also been investigated. Morphological and structural changes of the fibres were investigated using scanning electron microscopy and IR spectroscopy. Mechanical properties of untreated and treated fibres were studied. Changes in stress–strain characteristics, tensile strength, tensile modulus and elongation at break of the fibres upon various modifications were studied and compared. The incorporation of the modified fibres resulted in composites having excellent impact resistance. Fibre coating enhanced the impact strength of untreated composite by a factor of four. Tensile and flexural performance of the composites were also investigated. Finally, inorder to have an insight into the failure behaviour, the tensile and impact fracture surfaces of the composites were analysed using scanning electron microscope.

https://link.springer.com/content/pdf/10.1023/A:1026534006291.pdf

Oil Palm Fibre Reinforced Phenol Formaldehyde Composites: Influence of Fibre Surface Modifications on the Mechanical Performance

This article deals with the aspects of interfacial and surface characterization of natural fibers and their composites. Vegetable fibers and their composites have attracted the attention of scientists worldwide because of their favorable properties. The different chemical modifications of natural fibers and characterization aspects have been discussed. The adhesion between fiber and matrix is a major factor in determining the response of the interface and its integrity under stress. Therefore characterization of the interface is of utmost importance. Both fiber surface and polymer matrix surface can be modified to obtain a strong interface. Various treatments being used for the lignocellulosic surfaces and the characterization techniques have been illustrated. The four main techniques of interfacial characterization that are enumerated in this article are the micromechanical techniques, spectroscopic, microscopic and swelling techniques. The micromechanical techniques like fiber pull-out and fragmentation...

A study of advances in characterization of interfaces and fiber surfaces in lignocellulosic fiber-reinforced composites

The electrical properties of banana fiber-reinforced phenol formaldehyde composites have been studied with special reference to fiber loading, fiber treatments, and hybridization with glass fibers. The dielectric constant decreased with frequency and fiber loading. Treatments with silanes, NaOH and acetylation, latex treatment, heat treatment, and cyanoethylation decreased the dielectric constant value. The dielectric constant is higher for banana/PF composites than that of glass/PF composites. In hybrid composites, the dielectric constant decreased with increase in glass fiber concentration. The volume resistivity of banana fiber-reinforced phenol formaldehyde composites decreased with frequency and fiber loading. Chemical modifications in the fiber increased the volume resistivity of the composites. Volume resistivity of banana/glass hybrid composites increased with increase in glass fiber content. Layered composites with glass fiber at periphery were found to have higher volume resistivity than other layering patterns. The loss factor decreased by the chemical treatments and in hybrid composites it decreased with increase in volume fraction of glass fibers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Electrical properties of banana fiber‐reinforced phenol formaldehyde composites

Banana fibre has been modified with silane treatments, acetylation, cyanoethylation, latex treatment and mercerization to improve the interfacial bonding with phenol formaldehyde (PF) resin Scanning electron microscopy was used to study the morphology of the banana fibre The tensile properties of the modified fibre were compared with the untreated fibre and it was found that the tensile strength and modulus of the fibre were decreased by all the treatments except cyanoethylation Tensile, flexural and impact performance of phenol formaldehyde composites reinforced with various treated fibres were analyzed and compared with that of untreated fibre composite The tensile and flexural properties of the fibre-reinforced composites were found to be increased by all the modifications except latex coating Incorporation of heat-treated, vinyl silane-treated and acetylated fibre-reinforced PF composites was found to have higher impact strength than that of untreated fibre/compsites The tensile fractographs of 

Seena Joseph

Papers

A comparison of the mechanical properties of phenol formaldehyde composites reinforced with banana fibres and glass fibres

Oil Palm Fibre Reinforced Phenol Formaldehyde Composites: Influence of Fibre Surface Modifications on the Mechanical Performance

A study of advances in characterization of interfaces and fiber surfaces in lignocellulosic fiber-reinforced composites

Electrical properties of banana fiber‐reinforced phenol formaldehyde composites

The role of interfacial interactions on the mechanical properties of banana fibre reinforced phenol formaldehyde composites