Nattapron Siribanluehan. Preparation and characterization of durian husk-based biocomposite films reinforced with nanocellulose from pineapple leaves and corn husks. Master's Degree(Chemical Engineering). Burapha University. Library. : Burapha University, 2024.
Preparation and characterization of durian husk-based biocomposite films reinforced with nanocellulose from pineapple leaves and corn husks
Abstract:
Various agricultural wastes generally contain cellulose, which is one type of biopolymers and hence can be used to replace synthetic, non-biodegradable materials. In this study, corn husks nanocellulose (CHNc) and pineapple leaves nanocellulose (PLNc) were incorporated into carboxymethyl cellulose-based film made from durian husks (CMCDH) with different nanocellulose contents (15, 30, and 45 wt%) through solvent-casting method as reinforcement. Durian husks cellulose (DHC) was obtained via alkaline and bleaching processes before CMCDH synthesis by carboxymethylation using sodium hydroxide and sodium monochloroacetate in isopropyl alcohol. The corn husks (CH) and pineapple leaves (PL) were treated through alkaline and bleaching treatments before synthesizing nanocellulose using acid hydrolysis. The results from Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD) indicated that alkaline and bleaching treatments effectively removed non-cellulosic components. Additionally, during the carboxylation reaction, the hydroxyl group on DHC was substituted with a carboxyl group. TEM images indicated the successful preparation of CHNc and PLNc which achieved rod-like in shape and nanoscale in size, with a length and diameter of approximately 206.45 ± 41.10 nm × 7.24 ± 1.38 nm, and 150.68 ± 42.10 nm × 6.52 ± 0.96 nm, respectively. XRD data showed the increased crystallinity index (CI) values of CHNc and PLNc to 63.94 and 62.27%, respectively, as compared to those the untreated CH and PL at 32.76 and 46.01%, respectively, implying the effective removal of lignin and hemicellulose. The CMCDH composite films were examined for their UV-visible light transmittance, water vapor transmission rates (WVTR), mechanical properties, thermal stability, and biodegradability. The CMCDH composite films prepared in this work has yellowish appearance compared to commercial CMC composite films (CMCcom). The addition of nanocellulose (CHNc and PLNc) reduced the UV-visible light transparency of the CMCDH films but improved their water barrier, thermal stability, and tensile strength. The WVTR decreased from 2.77 to 2.33 and 2.10 gm2/h with 30 wt% of CHNc and PLNc, respectively. The highest tensile strength was obtained from CMCDH/PLNc(30%) with a value of 5.06 ± 0.83 MPa. However, agglomeration of PLNc at 45 wt% resulting in a decrease in tensile strength to 3.78 ± 0.44 MPa. Scanning electron microscopy (SEM) also confirmed the agglomeration of PLNc at high PLNc concentration. According to Thermogravimetric Analysis (TGA) and Differential Scanning Calorimeter (DSC), the addition of nanocellulose delayed decomposition temperature of CMCDH composite films by approximately 10 °C. Photodegradation study of the film under UV light irradiation of the wavelength of 320-400 nm indicated that after 2 days of irradiation, all the films were hard and brittle. However, the films color did not alter after 7 days of irradiation. For biodegradation investigation via soil burial test, all of the composite films completely degraded within 3 days. Therefore, the CMCDH biocomposite films prepared in this research can be an alternative material for solving environmental issues and promoting sustainable materials in packaging applications. In addition, this research counteracts with Bio-Circular-Green (BCG) economy model of Thailand.