Abstract:
Plastics are one of the derived products from petroleum material, which have been used in many applications worldwide, because of their various properties. However, plastic wastes create toxic environmental pollutions and problems because of their toxic constituents and non-biodegradability. Accordingly, nature materials have been proposed as a substitute for petroleum materials for bioplastic production. Natural rubber (NR) is a product from natural, which is well-known for its high elasticity. However, there are some drawbacks such as low tensile strength and low abrasion resistance. Moreover, its applications are also limited because of its poor resistance to oil and solvents. Therefore, the improvement of physical properties such as hardness, Young’s modulus, or abrasion resistance is required to improve the properties of NR.
In this study, In order to improve mechanical, chemical, and biological properties, natural rubber (NR) films were reinforced with cellulose (CE) and chitosan (CH). Chitosan powders at a molecular weight of 30,000 g/mol (CHS) and 500,000 g/mol (CHL) were used for the study. The CE/CH/NR composite films were successfully prepared via a latex aqueous microdispersion method with a different weight ratio of NR: CE: CHS/CHL. The CE/CH/NR composite films were characterized for physical, chemical, and biological properties. Fourier transform infrared spectroscopy (FTIR) results demonstrated strong interactions of hydrogen bonds between CE and CHS/CHL in the composite films. The tensile strength and the modulus of the composite films in dried forms were found to increase with the reinforcement of CE and CHS/CHL. The maximum tensile strength (13.8 MPa), Young’s modulus (12.74 MPa) were obtained from the composite films reinforced with CE at 10 wt% and CHS at 10 wt%. The maximum elongation at 526% was obtained from the composite films reinforced with CE at 10 wt% and CHL at 5.0 wt%. The addition of CE and CHS/CHL could also promote antimicrobial activities (100% for E. coli and 99% for S. aureus) and chemical resistance against non-polar solvents of the composite films. The NR composites films have potential uses as high elasticity NR products and green-polymer packaging.
