A comprehensive review of techniques for natural fibers as reinforcement in composites::preparation, processing and characterization

Designing environmentally friendly materials from natural resources represents a great challenge in the last decade. However, the lack of fundamental knowledge in the processing of the raw materials to fabricate the composites structure is still a major challenge for potential applications.Natural fibers extracted from plants are receiving more attention from researchers, scientists and academics due to their use in polymer composites and also their environmentally friendly nature and sustainability. The natural fiber features depend on the preparation and processing of the fibers. Natural plant fibers are extracted either by mechanical retting, dew retting and/or water retting processes. The natural fibers characteristics could be improved by suitable chemicals and surface treatments. This survey proposes a detailed review of the different types of retting processes, chemical and surface treatments and characterization techniques for natural fibers. We summarize major findings from the literature and the treatment effects on the properties of the natural fibers are being highlighted

Exploration of Electrical, Thermal, and Mechanical Properties of Phaseolus vulgaris Fiber/Unsaturated Polyester Resin Composite Filled with Nano–SiO2

In this study, the electrical, thermal, and mechanical properties of hybrid natural fiber composite are taken under consideration. Fly ash waste is used as the filler material. Unsaturated polyester resin is used as the matrix material to bind the composite. Alkali-treated Phaseolus vulgaris fiber (PVF) (5% NaOH for 45 min) is taken as the primary filler. Nanosilica synthesized is added to the composite samples at a constant percentage (1%). Samples of various weight percentages are prepared (2%, 4%, 6%, 8%, and 10% of PVF) and studied. Dielectric strength test for electrical property, thermal conductivity test for the thermal property, mechanical tests like tensile strength, Brinell hardness, Izod impact tests, and water absorption test are also taken under consideration. The composite showed a regular increasing trend in mechanical and electrical properties with varying weight percentages until 6% PVF; afterward, a decreasing trend in the mechanical and electrical properties of the composite was found with greater weight percentages. Whereas for thermal conductivity and water absorption tests, the results showed a regular decreasing trend until 6% PVF; afterward an increasing trend was found. It is found that the composite of 6% PVF and 1% SiO2 shows better electrical, thermal, and mechanical properties

Study on characterization and physicochemical properties of new natural fiber from Phaseolus vulgaris

Characterization of new natural fibres from various parts of plants have become increasingly popular not only in textile industries, automotive sector, electrical applications, and construction industries, but in various industrial applications because of their versatile characteristics, availability, biodegradability and providing sustainable solutions to support technical innovation. This study aimed to determine the characterization and physicochemical properties of Phaseolus vulgaris fibers (PVF) by Thermo gravimetric analysis (TGA)/DTG, X-Ray Diffraction analysis (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Eventually, fourier transform analysis and XRD analysis of PVFs demonstrated the presence of cellulose with a crystallinity index of 43.01%. The surface morphological analysis was observed and reveals that PVFs contain rougher surfaces, which would be favourable to develop good bonding with the matrix for making composites

Optimization Studies on Improving the Dielectric Properties of Alkali Treated Fibers from Phaseolus Vulgaris Reinforced Polyester Composites by Central Composite Design

This study investigates the dielectric efficiency of a composite prepared using a fiber extracted from Phaseolus vulgaris. The extraction of fiber was statistically modeled using face-centered central composite design. The concentration of NaOH and extraction time was taken as the process variables and dielectric strength was taken as the response. The numerically optimized model for the extraction of fiber from Phaseolus vulgaris of alkali treatment showed 14.325 kV/cm as dielectric strength of initial NaOH concentration of 3% and time period of 51 min. The model was significant with R2 = 0.9323 and adjusted R2 = 0.884. The linear, quadratic & interactive relationship between the response (dielectric strength) and variables (NaOH & time) was also established. This study explains the importance of NaOH and time period in establishing the fiber extraction by the alkali treatment process

Investigation on the Physicochemical and Mechanical Properties of Novel Alkali-treated Phaseolus vulgaris Fibers

This investigation is aimed to analyze the effect of sodium hydroxide (NaOH) treatment on the physical, chemical, structural, thermal and surface topography of Phaseolus vulgaris fibers (PVFs). The surface of raw PVFs was modified by soaking with 5% NaOH solution for 15, 30, 45 and 60 min. The various functional groups of the alkali-treated PVFs (APVFs) were studied Fourier-transform infrared spectroscopy. The outcomes of thermogravimetric analysis evident that the optimum treatment time for 5% NaOH was 45 min. It was noticed that optimally treated PVFs have higher cellulose (69.48 wt.%), crystallinity index (52.27%) and lower hemicellulose (4.30 wt.%), lignin (7.02 wt.%) contents. The thermogravimetric analysis (TGA) of PVFs also revealing moderate thermal stability was observed; atomic force microscopy (AFM) investigation inveterates that the surface of the fiber is rough and it will be a potential reinforcement for polymer composites

A comprehensive review of techniques for natural fibers as reinforcement in composites: Preparation, processing and characterization

Designing environmentally friendly materials from natural resources represents a great challenge in the last decade. However, the lack of fundamental knowledge in the processing of the raw materials to fabricate the composites structure is still a major challenge for potential applications. Natural fibers extracted from plants are receiving more attention from researchers, scientists and academics due to their use in polymer composites and also their environmentally friendly nature and sustainability. The natural fiber features depend on the preparation and processing of the fibers. Natural plant fibers are extracted either by mechanical retting, dew retting and/or water retting processes. The natural fibers characteristics could be improved by suitable chemicals and surface treatments. This survey proposes a detailed review of the different types of retting processes, chemical and surface treatments and characterization techniques for natural fibers. We summarize major findings from the literature and the treatment effects on the properties of the natural fibers are being highlighted