M.R. Nurul Fazita

A review on chitosan-cellulose blends and nanocellulose reinforced chitosan biocomposites: Properties and their applications

Chitin is one of the most abundant natural polymers in world and it is used for the production of chitosan by deacetylation. Chitosan is antibacterial in nature, non-toxic, and biodegradable thus it can be used for the production of biodegradable film which is a green alternative to commercially available synthetic counterparts. However, their poor mechanical and thermal properties restricted its wide spread applications. Chitosan is highly compatible with other biopolymers thus its blending with cellulose and/or incorporation of nanofiber isolated from cellulose namely cellulose nanofiber and cellulose nanowhiskers are generally useful. Cellulosic fibers in nano scale are attractive reinforcement in chitosan to produce environmental friendly composite films with improved physical properties. Thus chitosan based composites have wide applicability and potential in the field of biomedical, packaging and water treatment. This review summarises properties and preparation procedure of chitosan-cellulose blends and nano size cellulose reinforcement in chitosan bionanocomposites for different applications.

Microcrystalline cellulose: Isolation, characterization and bio-composites application-A review.

Considering its widespread usage in various fields, such as food, pharmaceutical, medical, cosmetic and polymer composites industries, microcrystalline cellulose (MCC) is becoming impellent due to increasing demand of alternatives to non-renewable and scarce fossil materials. Although it still suffers from some drawbacks, MCC has recently gained more interest owing to its renewability, non-toxicity, economic value, biodegradability, high mechanical properties, high surface area and biocompatibility. New sources, new isolation processes, and new treatments are currently under development to satisfy the increasing demand of producing new types of MCC-based materials on an industrial scale. Therefore, this review assembles the current knowledge on the isolation of MCC from different sources using various procedures, its characterization, and its application in bio-composites. Challenges and future opportunities of MCC-based composites are discussed as well as obstacles remaining for their extensive uses.

Exploring the effect of cellulose nanowhiskers isolated from oil palm biomass on polylactic acid properties

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 Youngs 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.

Physicochemical of microcrystalline cellulose from oil palm fronds as potential methylene blue adsorbents

The present study sheds light on the physical and chemical characteristics of microcrystalline cellulose (MCC) isolated from oil palm fronds (OPF) pulps. It was found that the OPF MCC was identified as cellulose II polymorph, with higher crystallinity index than OPF α-cellulose (CrIOPFMCC: 71%>CrIOPFα-cellulose: 47%). This indicates that the acid hydrolysis allows the production of cellulose that is highly crystalline. BET surface area of OPF MCC was found to be higher than OPF α-cellulose (SBETOPFMCC: 5.64m2g-1>SBETOPFα-cellulose:Qa0 2.04m2g-1), which corroborates their potential as an adsorbent. In batch adsorption studies, it was observed that the experimental data fit well with Langmuir adsorption isotherm in comparison to Freundlich isotherm. The monolayer adsorption capacity (Qa0) of OPF MCC was found to be around 51.811mgg-1 and the experimental data fitted well to pseudo-second-order kinetic model.

Empty Fruit Bunches as a Reinforcement in Laminated Bio-composites

In this article, we study laminated bio-composites that were reinforced with empty fruit bunches. Five-ply veneer laminated bio-composites were prepared by alternately arranging oil palm trunk veneer and empty fruit bunch mat. Composites were made with a gluing layer of 250 or 450 g/m2 of phenol formaldehyde. The mechanical, physical, and thermal (TGA) properties of the composite were studied. Results indicated an improvement in mechanical, physical, and thermal properties of the laminated bio-composites with the use of empty fruit bunches as reinforcement. The water absorption and thickness swelling of laminated bio-composites that were reinforced with empty fruit bunches were better than bio-composites not reinforced with empty fruit bunches. Laminated bio-composites with the use of empty fruit bunch as reinforcement showed better bending strength, bending modulus, and screw withdrawal. Thermal stability for laminated bio-composites with empty fruit bunch also improved. Images taken with a scanning electron micrograph indicated an improvement in the fiber-matrix bonding for the laminated panel glued with 450 g/m 2 of phenol formaldehyde.

Green Composites Made of Bamboo Fabric and Poly (Lactic) Acid for Packaging Applications—A Review

Petroleum based thermoplastics are widely used in a range of applications, particularly in packaging. However, their usage has resulted in soaring pollutant emissions. Thus, researchers have been driven to seek environmentally friendly alternative packaging materials which are recyclable as well as biodegradable. Due to the excellent mechanical properties of natural fibres, they have been extensively used to reinforce biopolymers to produce biodegradable composites. A detailed understanding of the properties of such composite materials is vital for assessing their applicability to various products. The present review discusses several functional properties related to packaging applications in order to explore the potential of bamboo fibre fabric-poly (lactic) acid composites for packaging applications. Physical properties, heat deflection temperature, impact resistance, recyclability and biodegradability are important functional properties of packaging materials. In this review, we will also comprehensively discuss the chronological events and applications of natural fibre biopolymer composites.

Influence of alkaline hydrogen peroxide pre-hydrolysis on the isolation of microcrystalline cellulose from oil palm fronds

In the present study, microcrystalline cellulose (MCC) was isolated from oil palm fronds (OPF) using chemo-mechanical process. Wherein, alkaline hydrogen peroxide (AHP) was utilized to extract OPF fibre at different AHP concentrations. The OPF pulp fibre was then bleached with acidified sodium chlorite solution followed by the acid hydrolysis using hydrochloric acid. Several analytical methods were conducted to determine the influence of AHP concentration on thermal properties, morphological properties, microscopic and crystalline behaviour of isolated MCC. Results showed that the MCC extracted from OPF fibres had fibre diameters of 7.55-9.11nm. X-ray diffraction (XRD) analyses revealed that the obtained microcrystalline fibre had both celluloses I and cellulose II polymorphs structure, depending on the AHP concentrations. The Fourier transmission infrared (FTIR) analyses showed that the AHP pre-hydrolysis was successfully removed hemicelluloses and lignin from the OPF fibre. The crystallinity of the MCC was increased with the AHP concentrations. The degradation temperature of MCC was about 300°C. The finding of the present study showed that pre-treatment process potentially influenced the quality of the isolation of MCC from oil palm fronds.

Exploring the potentials of nanocellulose whiskers derived from oil palm empty fruit bunch on the development of polylactid acid based green nanocomposites

In this study, nanocellulose whiskers (NCW) from oil palm empty fruit bunches (OPEFB) were used as reinforcement phase in polylactid acid (PLA). Two techniques were employed to isolate the NCW from OPEFB microcrystalline cellulose (OPEFB-MCC); chemical swelling with DMAc containing 0.5% LiCl to generate the NCW and acid hydrolysis with 64% H2SO4 to generate the NCW-S. The atomic force microscopy showed that the isolated NCW and NCW-S are in nanoscale dimension and displayed an individual rod-like structure. The fillers were then incorporated in PLA matrix at different loadings (1, 3, and 5 parts per hundred resin (phr)) to produce P-NCW and P-NCW-S nanocomposites via solution casting technique. The mechanical properties of the developed nanocomposites were investigated by means of tensile test. The results showed that the tensile strength of nanocomposites increased by 84% and 64% for the NCW and NCW-S reinforced PLA nanocomposites, respectively. The Youngs modulus of nanocomposites increased linearly with the fillers loading. Expectedly, the percent elongation at break was impacted negatively as it decreased with fillers loading. The thermogravimetric analysis showed that the decomposition temperatures (T10, T50 and Tmax) of P-NCW were higher than neat PLA. In the case of P-NCW-S however, the thermal stability decreased with the additional of NCW-S.

Woven Natural Fiber Fabric Reinforced Biodegradable Composite: Processing, Properties and Application

In recent years, the use of biodegradable polymers has become more popular due to the increasing awareness of the environmental impacts of petroleum-based plastics. The most feasible way toward having eco-friendly composites is the use of biodegradable polymer composite reinforced with natural fibers such as bamboo, kenaf, jute, sisal, ramie, flax and hemp. The research on natural fiber reinforced composites has generally been focused on the use of short fibers. Woven fabric has been employed in various applications which include aerospace, automotive parts and structural reinforcement due to their high strength and stiffness. Although there is less study being conducted regarding biodegradable polymer composites reinforced with natural fiber woven fabric, natural fibers possess many benefits when used as fabric, for instance, ease in handling of fibers and also the provision of homogenous distribution for the matrix and reinforcing fiber. Thus, this chapter is concerned with the processing, properties and applications of woven natural fiber fabric reinforced biodegradable composites.

Hybrid bast fiber reinforced thermoset composites

Abstract This chapter deals with the development of hybrid bast fiber reinforced thermoset composites. Hybrid bast fiber reinforced thermoset composites may consist of either bast/cellulosic fibers or bast/synthetic fibers as reinforcements. Hence, this chapter starts by introducing the bast fibers such as flax, hemp, jute, and kenaf as well as the bast fibers cell wall architecture with its illustration. It then goes on to explain the bast fibers chemical composition, physical and mechanical properties before further discussing the potential and challenges in the development of hybrid bast fiber composites. Next, an outline of reported research works on the processing, physical and mechanical properties of hybrid bast fiber reinforced thermoset composites are presented. Finally, the applications of the hybrid bast fiber reinforced thermoset composites are identified by the end of this chapter.