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The degradation and mechanical properties of potential polymeric materials used for green manufacturing are significant determinants. In this study, cellulose nanofibre was prepared from Schizostachyum brachycladum bamboo and used as reinforcement in the PLA/chitosan matrix using melt extrusion and compression moulding method. The cellulose nanofibre(CNF) was isolated using supercritical carbon dioxide and high-pressure homogenisation. The isolated CNF was characterised with transmission electron microscopy (TEM), FT-IR, zeta potential and particle size analysis. The mechanical, physical, and degradation properties of the resulting biocomposite were studied with moisture content, density, thickness swelling, tensile, flexural, scanning electron microscopy, thermogravimetry, and biodegradability analysis. The TEM, FT-IR, and particle size results showed successful isolation of cellulose nanofibre using this method. The result showed that the physical, mechanical, and degradation properties of PLA/chitosan/CNF biocomposite were significantly enhanced with cellulose nanofibre. The density, thickness swelling, and moisture content increased with the addition of CNF. Also, tensile strength and modulus; flexural strength and modulus increased; while the elongation reduced. The carbon residue from the thermal degradation and the glass transition temperature of the PLA/chitosan/CNF biocomposite was observed to increase with the addition of CNF. The result showed that the biocomposite has potential for green and sustainable industrial application.

In this work, polylactic acid (PLA) reinforced cellulose nanowhiskers (CNW) were prepared through solution casting technique. The CNW was first isolated from oil palm empty fruit bunch microcrystalline cellulose (OPEFB-MCC) by using 64% H2SO4 and was designated as CNW-S. The optical microscopy revealed that the large particle of OPEFB-MCC has been broken down by the hydrolysis treatment. The atomic force microscopy confirmed that the CNW-S obtained is in nanoscale dimension and appeared in individual rod-like character. The produced CNW-S was then incorporated with PLA at 1, 3, and 5 parts per hundred (phr) resins for the PLA-CNW-S nanocomposite production. The synthesized nanocomposites were then characterized by a mean of tensile properties and thermal stability. Interestingly to note that incorporating of 3 phr/CNW-S in PLA improved the tensile strength by 61%. Also, CNW-S loading showed a positive impact on the Young's modulus of PLA. The elongation at break (Eb) of nanocomposites, however, decreased with the addition of CNW-S. Field emission scanning electron microscopy and transmission electron microscopy revealed that the CNW-S dispersed well in PLA at lower filler loading before it started to agglomerate at higher CNW-S loading (5phr). The DSC analysis of the nanocomposites obtained showed that Tg,Tcc and Tm values of PLA were improved with CNW-S loading. The TGA analysis however, revealed that incopreated CNW-S in PLA effect the thermal stability (T10,T50 and Tmax) of nanocomposite, where it decrease linearly with CNW-S loading., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A sustainable and environmentally conscious approach was employed to create a cellulose nanofiber (CNF) bioaerogel. This modified technique was used for its affordability and eco‐friendly nature, involved the use of reduced concentrations of NaOH solution (ranging from 0 to 0.5 M) to disperse the CNFs. The process included mixing, freezing, neutralizing, and freeze‐drying, ultimately resulting in well‐structured 3D bioaerogels. The concentration of NaOH had a significant impact on the properties of the bioaerogels. The density of the aerogels increases with higher concentration of NaOH. All treated aerogels exhibited impressive water resistance and maintained their structural integrity when exposed to water, indicating promising practical applications. This enhanced structural integrity is attributed to CNF chain rearrangement, facilitated by CNF swelling, dissolution in NaOH, and homogenization. FTIR and XRD analyses provided insight into the transition from cellulose I to cellulose‐II in the bioaerogel structure. These findings contribute to the development of eco‐friendly bioaerogels for environmentally conscious applications. Further research is needed to gain a deeper understanding of the process and to optimize conditions for specific bioaerogel properties. [ABSTRACT FROM AUTHOR]

The objective of this study was to find the optimum amount of montmorillonite (MMT) to be incorporated with microcrystalline cellulose (MCC) to enhance physicochemical properties of oil palm empty fruit bunch (OPEFB)-based regenerated cellulose (RC). In this research, RC was synthesised by mixing 6.5 wt% of OPEFB-MCC with 1-butyl,3-methylimidazolium chloride [BMIM]Cl ionic liquid at 75°C by continuous stirring. RC nanocomposites were prepared by adding 1-5 wt% of montmorillonite (MMT) into RC preparation base. Finished solutions of both types were subjected to solution casting process to obtain thin films. Fourier transformation infrared (FTIR) spectroscopy, tensile test, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), water absorption and contact angle measurements were used as the characterisation tools. FTIR spectroscopy denotes the non-derivative behaviour of [BMIM]Cl ionic liquid. According to SEM images, moderate MMT loading is preferred since high MMT loading shows coarse morphology beyond 3 wt% of MMT. Tensile strength of RC 11 MPa was increased up to 30 MPa as maximum in 4 wt% of MMT loading. Compared with pure RC, TGA curves were shifted to right side with the increased MMT loading and that implies good thermal stability. The highest thermal stability can be seen when the MMT content is 4 wt% since its TGA curve was the rightmost than others. Therefore, MMT can be identified as a good inhibitor for RC to avoid thermal degradation at elevated temperatures. Water absorption was reduced as 91%-37% in 2 h and 96%-41% in 24 h when MMT was increased from 0-5 wt%. Similarly, their contact angle was increased from 30.5o-88.5o for the MMT loading of 0-5 wt%. According to all these results, 3-4 wt% of MMT loading can be proposed as the optimum amount to be added into an RC matrix to utilise these films in packaging, photocatalytic and electrically conductive applications. [ABSTRACT FROM AUTHOR]

Seaweed bio-composite films with different proportion of Lemang and Semantan bamboo microcrystalline cellulose (MCC) were fabricated via solvent casting. The seaweed/MCC composite films were flexible, transparent, and slightly yellow. The MCC particles further enhanced mechanical properties and opacity of films. The thermal stability of seaweed films was moderately improved upon addition of bamboo MCC particles. Bamboo MCC was found to be comparable to commercial MCC in reducing the water vapor permeability (WVP), water solubility (WS), and moisture absorption capacity (MSC) of seaweed films. The tensile strength (TS) of seaweed films was increased by 20 to 23% with addition of up to 5% MCC particles. In addition, bamboo MCC efficiently reduced the WVP of seaweed films comparable to commercial MCC particles. The WS of seaweed films was decreased by 10 to 19% with addition of 1% MCC particles loading. Lemang bamboo MCC (SB-MCC) was remarkably reduced the moisture absorption capacity (MAC) of films up to 25% with inclusion of only 1% MCC. Morphological analysis via Scanning Electron Microscopy (SEM) confirmed that there was homogeneous dispersion of MCC particles in the films. MCC particles improved the mechanical, thermal, and optical properties of seaweed films making them more suitable for food packaging applications. [ABSTRACT FROM AUTHOR]

Seaweed and cellulose are promising natural polymers. This article reviews the basic information and recent developments of both seaweed and cellulose biopolymer materials as well as analyses the feasible formation of seaweed/cellulose composite films. Seaweed and cellulose both exhibit interesting film-forming properties. Nevertheless, seaweed has poor water vapour barrier and mechanical properties, whereas cellulose is neither meltable nor soluble in water or common organic solvents due to its highly crystalline structure. Therefore, modification of these hydrocolloids has been done to exploit their useful properties. Blending of biopolymers is a must recommended approach to improve the desired characteristics. From the review, seaweed is well compatible with cellulose, which possesses excellent mechanical strength and water resistance properties. Moreover, seaweed/cellulose composite films can prolong a product's shelf life while maintaining its biodegradability. Additionally, the films show potential in contributing to the bioeconomy. In order to widen seaweed and cellulose in biocomposite application across various industries, some of the viewpoints are highlighted to be focused for future developments and applications. [ABSTRACT FROM AUTHOR]

Composite materials made from renewable resources can minimize the environmental pollution. In this work, biocomposite films were produced using seaweed as matrix and empty fruit bunch (EFB) pulp fibers as reinforcement. Based on the results, the EFB pulp-seaweed composite films exhibited better mechanical properties than the seaweed film. It was also observed that 50% EFB pulp loading gave the highest tensile strength (81.4 MPa) and elongation at break (5.4%). This phenomenon was supported by SEM analysis, in which more fiber breakage than fiber pull-out was observed on the tensile fracture surface of composite film. Additionally, no agglomeration of the pulp fibers was observed. Instead, the pulp fibers were homogenously distributed throughout the film. In contrast, the contact angle of the seaweed-based films started to decrease once the pulp fibers were added. The decrease in the contact angle was attributed to the hydrophilic nature of the pulp fibers. Nevertheless, the contact angle values of all composite films were still comparatively high and thus, this would not affect their application as a packaging film. [ABSTRACT FROM AUTHOR]

This article deals with the determination of chemical composition and the study of morphological and cell wall structure of oil palm fibers. Cellulose is the main constituent in oil palm fibers, and oil palm trunk (OPT) fiber exhibited the highest content of extractives and lignin. Fiber morphological determination also showed that OPT fibers have the highest fiber length, diameter, and cell wall thickness. Observations of fiber cell wall layers using transmisson electron microscopy at ultrastructure level confirmed that cell wall layers of oil palm fiber have a structure similar to that of wood cell wall. Analysis also focused on the determination of lignin distribution within the cell wall layers using toluidine blue. In all fiber samples, the middle lamella appeared to demonstrate a higher level of lignification compared to that of other cells. [ABSTRACT FROM AUTHOR]

Textile waste cellulose nanofibrillated fibre has been reported with excellent strength reinforcement ability in other biopolymers. In this research cellulose nanofibrilated fibre (CNF) was isolated from the textile waste cotton fabrics with combined supercritical carbon dioxide and high-pressure homogenisation. The isolated CNF was used to enhance the polylactic acid/chitin (PLA/chitin) properties. The properties enhancement effect of the CNF was studied by characterising the PLA/chitin/CNF biocomposite for improved mechanical, thermal, and morphological properties. The tensile properties, impact strength, dynamic mechanical analysis, thermogravimetry analysis, scanning electron microscopy, and the PLA/chitin/CNF biocomposite wettability were studied. The result showed that the tensile strength, elongation, tensile modulus, and impact strength improved significantly with chitin and CNF compared with the neat PLA. Furthermore, the scanning electron microscopy SEM (Scanning Electron Microscopy) morphological images showed uniform distribution and dispersion of the three polymers in each other, which corroborate the improvement in mechanical properties. The biocomposite's water absorption increased more than the neat PLA, and the contact angle was reduced. The results of the ternary blend compared with PLA/chitin binary blend showed significant enhancement with CNF. This showed that the three polymers' combination resulted in a better material property than the binary blend. [ABSTRACT FROM AUTHOR]

Global pollution from toxic metal waste has resulted in increased research on toxic metal adsorption. A cellulose acetate–polyurethane (CA–PU) film adsorbent was successfully prepared in this research. The cellulose acetate–polyurethane film adsorbent was prepared with a polycondensation reaction between cellulose acetate and methylene diphenyl diisocyanate. The CA–PU bond formation was confirmed by functional group analysis obtained from Fourier transform infrared (FTIR) spectroscopy. The obtained film was characterized for improved tensile and thermal properties with the addition of methylene diphenyl diisocyanate (MDI). The adsorption ability of the obtained film was evaluated with laser-induced breakdown spectroscopy (LIBS). The best film adsorbent from the LIBS was selected and studied for adsorption isotherm. The FTIR analysis confirmed the formation of the CA–PU bond from the polycondensation between cellulose acetate and the methylene diphenyl diisocyanate. The result showed that the addition of methylene diphenyl diisocyanate (MDI) resulted in the urethane network's growth. The characterization result showed an improvement in the morphology, thermal stability, and tensile strength of the film. The LIBS studies showed improvement in the adsorption of Pb2+ with CA–PU compared with the neat CA. The isotherm studies revealed that Pb2+ adsorption by cellulose acetate–polyurethane film adsorbent was heterogeneously dependent on the Freundlich isotherm model (R2 = 0.97044). Overall, the polycondensation method proposed by this study enhanced the Pb2+ removal, and was comparable to those reported in previous studies. [ABSTRACT FROM AUTHOR]