Natural fibre based composites are under intensive study due to their ecofriendly nature and peculiar properties. The advantage of natural fibres is their continuous supply, easy and safe handling, and biodegradable nature. Although natural fibres exhibit admirable physical and mechanical properties, it varies with the plant source, species, geography, and so forth. Pineapple leave fibre (PALF) is one of the abundantly available wastes materials of Malaysia and has not been studied yet as it is required. A detailed study of chemical, physical, and mechanical properties will bring out logical and reasonable utilization of PALF for various applications. From the socioeconomic prospective, PALF can be a new source of raw material to the industries and can be potential replacement of the expensive and nonrenewable synthetic fibre. However, few studies on PALF have been done describing the interfacial adhesion between fibres and reinforcement compatibility of fibre but a detailed study on PALF properties is not available. In this review, author covered the basic information of PALF and compared the chemical, physical, and mechanical properties with other natural fibres. Furthermore, it summarizes the recent work reported on physical, mechanical, and thermal properties of PALF reinforced polymer composites with its potential applications.

In this study, sugar palm starch (SPS) films were developed using glycerol (G), sorbitol (S) or their combination (GS) as plasticizers at the ratio of 15, 30 and 45 (wt)% using casting technique. The addition of plasticizers to SPS film-forming solutions helped to overcome the brittle and fragile nature of unplasticized SPS films. Increased plasticizer concentration resulted to an increase in film thickness, moisture content and solubility. On the contrary, density and water absorption of plasticized films decreased with increasing plasticizer concentration. Raising the plasticizer content from 15 to 45 % showed less effect on the moisture content and water absorption of S-plasticized films. Films containing glycerol and glycerol-sorbitol plasticizer (G, and GS) demonstrated higher moisture content, solubility and water absorption capacity compared to S-plasticized films. The results obtained in this study showed that plasticizer type and concentration significantly improves film properties and enhances their suitability for food packaging applications.

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.

The development and characterization of environmentally friendly bilayer films from sugar palm starch (SPS) and poly(lactic acid) (PLA) were conducted in this study. The SPS-PLA bilayer films and their individual components were characterized for their physical, mechanical, thermal and water barrier properties. Addition of 50% PLA layer onto 50% SPS layer (SPS50-PLA50) increased the tensile strength of neat SPS film from 7.74 to 13.65MPa but reduced their elongation at break from 46.66 to 15.53%. The incorporation of PLA layer significantly reduced the water vapor permeability as well as the water uptake and solubility of bilayer films which was attributed to the hydrophobic characteristic of the PLA layer. Furthermore, scanning electron microscopy (SEM) image of SPS50-PLA50 revealed lack of strong interfacial adhesion between the SPS and PLA. Overall, the incorporation of PLA layer onto SPS films enhances the suitability of SPS based films for food packaging.

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The aim for this work is to investigate the effect of alkaline treatment on the mechanical, physical and thermal properties of roselle (RF)/sugar palm fiber (SPF) reinforced thermoplastic polyurethane hybrid composites. RF/SPF hybrid composites were fabricated at different NaOH concentrations (3%, 6% and 9%) by melt mixing and compression molding. The mechanical, physical and thermal properties of RF/SPF hybrid composites were measured. The morphological properties of the tensile fractured sample were examined using scanning electron microscope. Obtained results indicated that the effect of NaOH treatment on the surface improved mechanical, physical and thermal properties accompanied by lower impact resistance. The highest tensile is 14.26 MPa, flexural strength is 14.05 MPa and impact strength is 23.76 kJ/M2) was obtained from treatment 6% NaOH concentration on RF/SPF hybrid composites. Adhesion bonding between fiber and matrix was evident by using Scanning electron microscopy (SEM) micrograph of hybrid composite tensile fractured. Scanning electron micrograph of tensile fractured surfaces of the NaOH treated RF/SPF hybrid composites revealed good adhesion bonding between fiber and matrix. Fourier transform infrared spectroscopy analysis was used to observe the effectiveness of NaOH treatment in the removal impurities on fiber surfaces. Thermogravimetric analysis showed that the treated RF/SPF hybrid composites had improved the thermal stability. Physical properties showed lower water uptake of the treated thermoplastic polyurethane hybrid composites. The lowest water uptake is 7.97% and thickness swelling is 6.49% obtained from 9% NaOH concentration after soaked in water for 7 days. Overall, the surface treatment on RF/SPF hybrid composite has enhanced the composite properties and suitable for automotive part application; battery holder and bottom based.

Roselle fibre is a type of natural fibre that can be utilized as apotential reinforcement filler in polymer composites for different applications. This work investigates the chemical, physical, mechanical, morphological, and thermal characteristics of roselle fibre at different levels of maturity (3, 6, and 9 months). The diameter of roselle fibre increases as the plant matures. However in contrast to this, the moisture content and water absorption of roselle fibre decrease as the plant matures. Chemical content of roselle fibres from plants of different ages indicate that as the plant matures, the cellulose content decreases. Tensile strength of roselle fibre decreases from 3 months old to 9 months old. The cross section of roselle fibre shows a typical morphology of bast fibre, where there is a lumen in the central of fibre.Thermal analysis results show that the effect of thermal decomposition of roselle fiber is almost the same for all plant ages. It is concludedthat roselle fibres can be used as reinforced material for manufacturing of polymer composites. Based on its excellent properties, roselle fibres are suitable for different applications such as automotive and building components at lower cost.

Kenaf (Hibiscus Cannabinus) bast fiber reinforced poly(vinyl chloride) (PVC)/thermoplastic polyurethane (TPU) poly-blend was prepared by melt mixing method using Haake Polydrive R600 internal mixer. The composites were prepared with different fiber content: 20%, 30% and 40% (by weight), with the processing parameters: 140 °C, 11 min, and 40 rpm for temperature, time and speed, respectively. After mixing, the composite was compressed using compressing molding machine. Mechanical properties (i.e. tensile properties, flexural properties, impact strength) were studied. Morphological properties of tensile fracture surface were studied using Scanning electron microscope (SEM). Thermal properties of the composites were studied using Thermogravimetric Analyses (TGA). PVC/TPU/KF composites have shown lower tensile strength and strain with increase in fiber content. Tensile modulus showed an increasing trend with increase in fiber content. Impact strength decreased with increase in fiber content; however, high impact strength was observed even with 40% fiber content (20.2 kJ/m2). Mean while; the 20% and 30% fiber contents showed higher impact strength of 34.9, 27.9 kJ/m2; respectively. SEM showed that there is poor fiber/matrix adhesion. Thermal degradation took place in three steps. In the first step, composites as well as the matrix had a similar stability. At the second step, matrix showed a slightly better stability than the composites. At the last step, composites showed a better stability than the matrix.