Mechanical Properties of Arecanut and GFR Hybrid Polypropylene Composites

The mechanical characteristics of hybrid polypropylene composites may be enhanced by adjusting the fibre loading and ratio, according to this study. The hot press technique was utilised to generate a variety of composites with four different amounts of fibre loading. In addition, the fibre ratio in composites with a 20-weight-percent fibre loading was changed. The composites were characterised using Fourier transform infrared analysis as well as tensile, flexural, and hardness tests. In the composites that have been created, Fourier transform infrared examination showed that hemicelluloses, lignins, and moisture were present, all of which have the potential to reduce tensile strength. Fibre loading resulted in a decrease in tensile strength but an increase in Young’s modulus. With increasing fibre loading, flexural modulus and hardness rose, whereas flexural strength declined. The best mechanical qualities were found in a composite made primarily of arecanut and glass fibres, with a weight ratio of 1 : 3.

1. Introduction
Design freedom is provided by hybrid fibre–polymer systems, which allow for the tailoring of composites and the attainment of qualities not possible in binary systems comprising the same fibre/filler in matrix [1]. In few cases, benefits of one fibre can outweigh the drawbacks of another. As a result, proper material design could bring about a performance-to-cost equilibrium [2, 3]. Automotive industry is the primary consumer of natural fibres because of their functional characteristics. Mirror frames, doors, windows, and other interior sections can all be made from composites, as can truck cabs, panels, shelves, and other trim components [4–6]. Composites are also popular in the production of brake shoes. Palm tree species (Areca catechu) bear the arecanut fruit (also known as the arecanut) and are found throughout Asia [7]. Fibres made from arecanuts are inexpensive. The fundamental issue with natural fibre composites is their incompatibility with polymer matrixes due to the hydrophobic nature of natural fibres [8–10].

Polymeric matrix composites commonly use glass fibres as reinforcement. Many applications benefit from its low cost, strong tensile strength, resistance to chemicals, and insulating properties [11, 12]. Among the most commonly used types of fibres in fibre reinforced plastics, E and S glass are the most prevalent. E-glass fibres are the most commonly utilised reinforcing glass fibres in the fibre-reinforced plastic industry because of their low cost [13, 14]. It is possible to get the desired properties by combining fibres in the right way and orienting them in the right direction. Fibre composites are stiffer than aluminium and have a specific gravity one-fourth that of steel, but they have the same functional properties as steel [15]. In the nautical, automotive, and piping industries, glass fibre-reinforced composites (GFRCs) have become increasingly popular because of specific strength and stiffness, along with their resilience to corrosion and impact damage [16]. Fillers, on the other hand, enhanced the properties of composites while also lowering the overall cost of the final product. We see polymers in practically every facet of modern life, from high-tech devices like artificial hip and knee joints to single-use plastic utensils for food [17].

Linear hydrocarbon polymers such as polypropylene are widely utilised in textiles, lab equipment, and automobile parts. Polypropylene is available in densities varying from 0.91 to 0.97 g/cc and is completely linear [18]. Polypropylene composites offer good flowability, mechanical properties, weatherability, and chemical resistance and are cost-effective when compared to other materials. These composites are widely employed as a key raw material, particularly in vehicle parts. Natural fibres that have been hybridized with synthetic fibres have been the subject of extensive study. However, no studies have been done on the use of arecanut and glass fibres in a polypropylene matrix. It is so hoped that this paper may provide some light on the hybridization of arecanut and glass fibres with polypropylene [19, 20]. Because of its inexpensive price, polypropylene was selected as the matrix material. Our approach of making eco-friendly hybrid composites out of natural fibres is described in this publication [4, 21, 22]. The paper focuses on the interaction of arecanut fibres with glass and polypropylene in this application.

Hybrid fibre-based polymer composites are created all over the world to give designers greater creative freedom when creating composites and to provide features that cannot be achieved in binary systems using only a kind of fibre or filler discrete in the matrix [23, 24]. They provide balanced strength and stiffness, increased bending and mechanical characteristics, improved fatigue and impact resistance, improved fracture toughness and crack arresting qualities, and decreased weight and cost. Polymer-based composites have been used to tackle technological difficulties since the 1960s [22]. Fibre composites that combine two or more types of fibre can fill in the gaps left by the omissions in the original design. As a result, good material design allowed for a trade-off between performance and cost. To improve the composite’s mechanical strength and other qualities, stronger synthetic or natural fibres can be hybridized with natural fibres [25]. The automotive sector prefers natural fibres because of their beneficial properties. Because of its biodegradable nature, natural fibre-reinforced composites are both low-cost and environmentally friendly. As an additional benefit, lignocellulose fibres are nonabrasive, light in weight, and easy to get. They also take less energy to process, decrease the density of finished products, and absorb carbon dioxide at the time of their growth. For composites, lignocellulose fibres can be blended with either thermosetting or thermoplastic polymers. However, thermosetting polymers show the composite to be extremely brittle, making it impossible to repair. Natural fibres, despite their amazing properties, have gained popularity due to their little impact on the environment [4]. This palm tree, known as the Areca catechu, produces the arecanut fruit, which is widely available and thrives throughout Asia [26]. Due to deficiency of compatibility between natural fibres and the hydrophobic qualities of polymer matrix, the fundamental impediment to using natural fibre composites is lower fibre–matrix interfacial bond.

On the other hand, polymeric matrix composites are commonly reinforced with glass fibres. Because of their inexpensive price, strong tensile strength, good chemical resistance, and excellent insulation, these materials are often preferred over others [27]. Fibre-reinforced plastics commonly use S-glass and E-glass fibres. Commercially accessible reinforcing glass fibres are more expensive than E-glass fibres. These composites have been tested for their mechanical properties. Composites bonded with polyester and oil palm fibre/glass were made for research in another work [28]. The researchers also looked at flax/glass-reinforced composites, jute/glass-reinforced composites, and basalt/glass-reinforced composites. There are a lot of studies being done that use a combination of glass and a natural fibre.