Nanocellulose has recently gained a significant level of attention from academic and industrial researchers due to its non-toxic, biocompatible, bio-degradable, low-cost, and easy availability that connects many applications. In this research, cellulose extracted from betel nut husk fiber (BNHF) was converted to nanocellulose by chemical technique to examine their potential for use as reinforcement in bio-composite applications. The cellulose isolated from BNHF was subjected to acid hydrolysis using 62% sulfuric acid under ultrasonic treatment to convert cellulose into nanocellulose. The particle size of nanocellulose was determined by particle size analyzer. The morphology, structure and thermal properties of nanocellulose were also determined by scanning electron microscope (SEM) and Fourier-transform infrared (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetric (DSC) analysis. The bio-composites of nanocellulose–polyvinyl alcohol (PVA) and cellulose–PVA were prepared with different weight percentages (1–5%) of nanocellulose and cellulose via casting methods. The tensile, thermal and morphological properties were characterized for all composites. Enhancement in the tensile, thermal, and morphological properties was found in the nanocellulose–PVA biocomposites.

Conductive polymer composites are becoming more important and useful in many electrical applications. This paper reports on the carbon black (CB) reinforced polyvinyl chloride (PVC) conductive composites. Conductive filler CB was reinforced with thermoplastic PVC by compression molding technique to make conductive composites. The particle size of CB was measured, as it affects the electrical conductivity of the composites. Different types of CB-PVC compression-molded composites were prepared, using CB contents from 5 to 30 wt %. The electrical and tensile properties of these composites were studied and compared. Improved electrical properties were obtained for all CB-PVC conductive polymer composites compared to virgin PVC composite. However, the tensile properties of the CB-PVC composites increased up to 15 wt % CB loading, and then decreased, and elongation at break decreased with increasing CB loading. The structure of the CB, PVC and CB-PVC composites were studied by attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopic analysis. ATR-FTIR spectra provide evidence of the formation of CB-PVC composites. The microstructural analyses showed a good dispersion of CB in PVC matrix.

Use of natural fiber as reinforcing material is the latest invention of polymer science in order to get higher strength with lower weight composite materials having several applications. In this present investigation banana fiber, a natural fiber, is used as the reinforcing material. Low density polyethylene (LDPE)-banana fiber reinforced composites were prepared using both untreated and bleached (treated) banana fiber and LDPE with 7.5, 15, 22.5 and 30% weight content of fibers by using compression molding technique. Physico-mechanical properties (e.g. tensile strength, flexural strength, elongation at break, Young's modulus) of different types of prepared composites were characterized. From this study it is observed that all these values have augmented up to a definite percentage. The tensile strengths and flexural strengths of the composites increased up to 22.5% fiber addition then started to decrease gradually. Young moduli of the composites increased with the increase of fiber addition. Water absorption also increased with the weight of the fiber. Whereas elongation at break decreased with increasing fiber loading. Mechanical properties of bleached banana fiber-LDPE composites were slightly higher than the untreated banana fiber-LDPE composites. Compared to virgin molded LDPE both tensile and flexural strengths and Young moduli of these LDPE-banana fiber composites were significantly higher. All the variable properties like tensile strength, flexural strength, and water absorption capacity showed a very significant role in these polymer composites. Keywords: Banana fiber; LDPE; Composite; Tensile strength; Flexural strength DOI: 10.3329/bjsir.v45i2.5708 Bangladesh J. Sci. Ind. Res. 45(2), 117-122, 2010