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The fiber-filled polymer composite is one of the best materials which provides a symmetrical superior strength and stiffness to structures. With the strengthening of people's environmental protection and resource reuse consciousness, the development of renewable materials, especially natural fiber-filled polymer composites, is receiving great attention. This study investigated the mechanical properties of polymer composites incorporating waste materials from the food processing industry and agricultural sources. Waste vegetal fiber-filled polymer biocomposites (WVFFPBs) with varying fiber types and 3D printing orientations were systematically fabricated. Subsequently, the tensile tests were executed to comprehensively assess the anisotropic mechanical behaviors of the WVFFPBs. The results demonstrated that WVFFPBs performed excellent anisotropic mechanical properties compared to pristine matrix samples as print orientation changed. As the printing angle increased from 0° to 90°, the tensile mechanical properties of the WVFFPBs displayed a decreasing trend. Moreover, the print orientation–anisotropic mechanical behavior relationship of 3D-printed WVFFPBs was revealed through the analysis of the material manufacturing characteristics and damage features. [ABSTRACT FROM AUTHOR]

The usage of new cellulosic fibers in industrial applications is massive because of its excellent performances. These fibers are utilized especially for manufacture of high-performance composites. Coconut leaf sheath (CLS) fibers are extracted for leaf sheath of coconut tree. The aim of this paper is to study the possibility of using a natural fiber CLS as an alternative for polymer composites. In the current study, the consequence of NaOH treatment on structural, thermal and morphological behavior of treated and untreated coconut leaf sheath (CLS) fiber in terms of single fiber tensile strength, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (×RD), ther)mogravimetric analysis (TGA) and differential scanning calorimeter (DSC) has been explored. From SEM analysis, it was identified globular lumps spread consistently over the fiber which could help the mechanical interlock with the resin. The outcomes from the experimentation exposed that the NaOH treatment has impacted in the eradication of amorphous hemicellulose and lignin contents from the CLS fiber surface and in turn resulted in excellent structural and thermal stability behaviour of fiber. The present work endorses the great potential of CLS fibers to be utilized for bio-reinforcement in order to fabricate lightweight composite structures, employed in automobile and structural applications. [ABSTRACT FROM AUTHOR]

Natural fibre biopolymer composites with both fibres and matrix being derived from biomaterials are increasingly used in demanding applications, such as sensing, packaging, building, and transport, and require good electrical, thermal, and flame retardant properties. Herein, an investigation of the effectiveness of functionalising nonwoven cotton/poly(lactic acid) (PLA) fibre mats with graphene oxide nanosheets has been reported by using a facile dip-coating method followed by thermal reduction for enhancing the electric, thermal, and abrasion-resistance properties. The manufacturing processes for preparing biocomposites and introducing functionality are readily scalable. Experimental results reveal that with the addition of less than 0.5 wt% graphene nanoplatelets, the biocomposites showed significant improvements in abrasion resistance, electrical conductivity, thermal conductivity, and diffusivity. Furthermore, the composite shows excellent piezo-resistivity to act as strain sensors with a gauge factor of 2.59 at strains up to 1%. [ABSTRACT FROM AUTHOR]

The growing awareness of socioeconomic and environmental issues and the high percentage of petroleum resources consumed and new environmental regulations have fueled efforts to develop innovative, cutting-edge, environmentally friendly materials with a wide range of applications. Due to environmental and sustainability concerns, the advancement of biocomposites has resulted in tremendous breakthroughs in green materials in this century. Their primary goal is to replace current synthetic petroleum-based composites with natural resources. Materials derived from nonrenewable petroleum-based sources are hazardous and expensive to produce; on the other hand, biocomposites derived from natural sources are biodegradable, recyclable, non-abrasive, and compostable and have properties comparable to synthetic fiber composites. Natural fibers are low-cost, lightweight, biodegradable, renewable, and environmentally friendly alternatives to synthetic fibers like glass and carbon fiber. The long-term viability of natural fiber-based composite materials has led to increased use in various production industries. However, the manufacturing process of natural fiber-based biocomposites is still plagued by some difficulties, such as poor adhesive propensity, moisture absorption, poor fire resistance, low impact strength, and low durability. This review provides a panoramic view to provide insight into different aspects of biocomposites based on natural fibers and polymers in terms of properties and applications, which will pave the way for future biocomposites research in academic and commercial contexts. [ABSTRACT FROM AUTHOR]

In this era of green and sustainable manufacturing, natural fibre-reinforced polymer composites (NFPC) have been widely accepted as the potential alternatives for polymer matrix composites (PMC) or any other non-biodegradable composites. Despite the increasing need to replace plastic bottles, bags, disposable plastic plates and trays, seedling pots used in our day to day life, not many studies have been made in this direction. The current work aims at developing a hundred percent biodegradable composite by reinforcing waste Kibisu silk fibre into wheat gluten as a possible replacement of plastic disposables. The developed composites are made up of different mass fractions of Kibisu silk fibre reinforced into plasticised wheat gluten. The prepared composites have been characterised to obtain the best combination. The developed composites were found to have adequate tensile property, mass degradation at a considerably high temperature and most importantly, the outstanding rate of biodegradation under normal atmospheric conditions. The soil quality test before and after degradation also showed no significant changes in the quality of the soil. FTIR studies revealed improved interaction between wheat gluten, glycerol and Kibisu fibres upon addition of natural lemon extract as crosslinker. Overall results indicate that the developed biocomposites have the potential to substitute harmful plastic disposables like plastic seedling pots and plates, disposable hospital tray, dustbin, etc. [ABSTRACT FROM AUTHOR]

Natural fibres retrieved from annual agricultural by-products offer diverse advantages, when applied as a main ingredient in biocomposite building materials. These fibres, such as straw and other non-wood fibres are annually renewable and are worldwide available having the lowest cost, in comparison to other natural fibres available in the industrial fibre market. In this paper, the author presents three case studies of natural fibre reinforced polymers (NFRP), discussing the agro-fibre densification, different architectural designs for customized applications and fabrication stages. The natural fibres were compounded with three different biopolymers: a thermoplastic, a thermoset and an elastic thermoplastic one. This allowed variations in the final designs and geometries that can be reached, but caused a necessity of changing the fabrication technique in each case accordingly. To prove the applicability of the developed products, mechanical properties and environmental assessment were analyzed. [ABSTRACT FROM AUTHOR]

• Bio-based FRPs can effectively strengthen concrete structures. • Flax and jute are the most used natural fibres, and epoxy is the most used matrix in bio-based FRP composites. • Economic biopolymers need to be developed as matrix materials to make complete biocomposites for structural retrofitting. • The durability of bio-based composites for structural applications needs further evaluation. Fibre-reinforced polymer (FRP) laminates/sheets have been used to retrofit concrete structures. Increased global awareness of environmental protection needs and recent legislation have propelled researchers to develop more environmentally friendly FRP materials to be used in place of synthetic FRP materials. Through a bibliometric and systematic literature review, this article reports on research on the use of bio-based FRP materials comprising of either natural fibres or biopolymers as external reinforcement for concrete structures. Eighty-seven experimental studies retrieved from Scopus and Google scholar databases were considered for this study. Analysis and visualization of research output per year and region, re-occurring keywords, co-authorship network and document co-citation networks are presented. The effects of various bio-based FRP materials used to strengthen various concrete members considering different FRP fabrication techniques and FRP configurations are presented. The study revealed that bio-based FRPs could effectively strengthen concrete beams and columns. Durability, cost and sustainability of these materials are also discussed. The paper also outlines pathways for further research and considerations for developing design frameworks. [ABSTRACT FROM AUTHOR]

Rapid exhaustion of petroleum resources coupled with increasing awareness of global environmental problems related to the use of conventional plastics are the main driving forces for the widespread acceptance of natural fibers and biopolymers as green materials. Natural fibers and biopolymers have attracted considerable attention of scientist and industries due to their environmentally friendly and sustainable nature. Sugar palm is a multipurpose tree grown in tropical countries and it is regarded as a potential source for natural fibers and biopolymer. Sugar palm fibers (SPF) are mainly composed of cellulose ( ~ 66.49%) which leads to their outstanding mechanical properties. The starch extracted from sugar palm tree can be plasticized, blend with other polymers or reinforced with fibers to enhance their properties. From literature review, it is clear that no comprehensive review paper published on sugar palm fibers, starch, and its biocomposites. Present review focuses on recent works related to properties of sugar palm fibers and starch, and their fabrication as green composites. The review also unveils the potential of sugar palm fibers and biopolymer for industrial applications such as automotive, packaging, bioenergy and others. [ABSTRACT FROM AUTHOR]

Over recent years, enthusiasm towards the manufacturing of biopolymers has attracted considerable attention due to the rising concern about depleting resources and worsening pollution. Among the biopolymers available in the world, polylactic acid (PLA) is one of the highest biopolymers produced globally and thus, making it suitable for product commercialisation. Therefore, the effectiveness of natural fibre reinforced PLA composite as an alternative material to substitute the non-renewable petroleum-based materials has been examined by researchers. The type of fibre used in fibre/matrix adhesion is very important because it influences the biocomposites' mechanical properties. Besides that, an outline of the present circumstance of natural fibre-reinforced PLA 3D printing, as well as its functions in 4D printing for applications of stimuli-responsive polymers were also discussed. This research paper aims to present the development and conducted studies on PLA-based natural fibre bio-composites over the last decade. This work reviews recent PLA-derived bio-composite research related to PLA synthesis and biodegradation, its properties, processes, challenges and prospects. [ABSTRACT FROM AUTHOR]

Fiber–matrix interfacial adhesion is one of the key factors governing the final properties of natural fiber-based polymer composites. In this work, four extrusion reactive agents were tested as potential compatibilizers in polyhydroxylbutyrate (PHB)/cellulose composites: dicumyl peroxide (DCP), hexamethylene diisocyanate (HMDI), resorcinol diglycidyl ether (RDGE), and triglycidyl isocyanurate (TGIC). The influence of the fibers and the different reactive agents on the mechanical properties, physical aging, and crystallization behavior were assessed. To evaluate the compatibilization effectiveness of each reactive agent, highly purified commercial cellulose fibers (TC90) were used as reference filler. Then, the influence of fiber purity on the compatibilization effect of the reactive agent HMDI was evaluated using untreated (U_RH) and chemically purified (T_RH) rice husk fibers, comparing the results with the ones using TC90 fibers. The results show that reactive agents interact with the polymer matrix at different levels, but all compositions showed a drastic embrittlement due to the aging of PHB. No clear compatibilization effect was found using DCP, RDGE, or TGIC reactive agents. On the other hand, the fiber–polymer interfacial adhesion was enhanced with HMDI. The purity of the fiber played an important role in the effectiveness of HMDI as a compatibilizer, since composites with highly purified fibers showed the greatest improvements in tensile strength and the most favorable morphology. None of the reactive agents negatively affected the compostability of PHB. Finally, thermoformed trays with good mold reproducibility were successfully obtained for PHB/T_RH/HMDI composition. [ABSTRACT FROM AUTHOR]