Mohammed Nasir

A Review on Pineapple Leaves Fibre and Its Composites

Natural fibre based composites are under intensive study due to their ecofriendly nature and peculiar properties. The advantage of natural fibres is their continuous supply, easy and safe handling, and biodegradable nature. Although natural fibres exhibit admirable physical and mechanical properties, it varies with the plant source, species, geography, and so forth. Pineapple leave fibre (PALF) is one of the abundantly available wastes materials of Malaysia and has not been studied yet as it is required. A detailed study of chemical, physical, and mechanical properties will bring out logical and reasonable utilization of PALF for various applications. From the socioeconomic prospective, PALF can be a new source of raw material to the industries and can be potential replacement of the expensive and nonrenewable synthetic fibre. However, few studies on PALF have been done describing the interfacial adhesion between fibres and reinforcement compatibility of fibre but a detailed study on PALF properties is not available. In this review, author covered the basic information of PALF and compared the chemical, physical, and mechanical properties with other natural fibres. Furthermore, it summarizes the recent work reported on physical, mechanical, and thermal properties of PALF reinforced polymer composites with its potential applications.

Isolation and characterization of cellulose nanocrystals from parenchyma and vascular bundle of oil palm trunk (Elaeis guineensis).

In this study cellulose nanocrystals were isolated through acid hydrolysis process from parenchyma and vascular bundle of oil palm trunk (Elaeis guineensis). The morphological properties of obtained cellulose nanocrystals were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The microscopy images showed smoother and cleaner surface of parenchyma cellulose nanocrystals when compared to vascular bundle cellulose nanocrystals. The TEM image shows a higher length and diameter for parenchyma cellulose nanocrystals compared to vascular bundle cellulose nanocrystals. The Fourier transform infrared (FTIR) spectra showed changes in functional groups after acid hydrolysis due to removal of lignin, hemicelluloses and other impurities in both type of cellulose nanocrystals. Crystallinity index of cellulose nanocrystals was observed higher for vascular bundle as compared to parenchyma. Thermogravimetric analysis (TGA) was performed to study the thermal stability of cellulose nanocrystals and it was observed higher for parenchyma cellulose nanocrystals compared to vascular bundle.

Laccase application in medium density fibreboard to prepare a bio-composite

Laccase efficacy as a biological tool for the removal of lignin in pulp industries is evident and has scope for a wider application. In this research study, rubber wood (Hevea brasiliensis) fibres were treated with laccase enzyme to study its effect on the fibre surface and the enzyme hydrolysis lignin (EHL) was collected as a byproduct. Collected EHL was concentrated (con) until the solution reached a 3% solid content. Fibre surface modification was studied by FESEM, FTIR and XRD. A distinct fibre surface with an improved crystallinity index was observed. EHL and Con-EHL were analyzed on a viscometer, FTIR, DSC, and TGA. Con-EHL exhibits a lower stretching energy at the benzene range compared to EHL and a curing pattern similar to UF was reported. To evaluate the capability of modified fibre and Con-EHL, 6 mm medium density fibreboard (MDF) of 810 kg m−3 were prepared by using 10% Con-EHL solution (by weight of fibre). The MDF boards exhibit higher mechanical strength and have passed the ASTM D1037 standard for internal bonding and modulus of rupture.

Natural Fiber Improvement by Laccase; Optimization, Characterization and Application in Medium Density Fiberboard

ABSTRACT Crystallinity of cellulosic fiber directly affects the physical and chemical behavior of the individual fiber and ultimately the product made from. In a controlled condition, if the natural fiber is exposed to enzymatic hydrolysis, its crystallinity improves without affecting the cellulose component of the fiber. In this work, four basic factors for enzymatic reaction, i.e., temperature, time, pH, and enzyme amount, were optimized using response surface methodology (RSM). The response was taken as the fiber crystallinity index, measured by X-ray diffraction method. The optimum treated fiber was further analyzed for the field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA) and results were compared with untreated fiber. Medium density fiberboards (MDF) were manufactured from optimum treated fiber and its tensile properties and water resistance properties were compared with MDF made from untreated fiber. The observation revealed a maximum of up to 14% increment in fiber crystallinity index (CrI) as compared to untreated fiber. The MDF prepared from optimum treated fiber exhibits improved tensile property and lower water absorption property as compared to MDF prepared from untreated fibers.

Nanocellulose: Preparation methods and applications

Abstract Cellulose is a multilevel, complex molecular structure built from superfine fibrils having diameters in the nanoscale. These nanofibrils contain highly ordered nanocrystallites and low-ordered whiskers in nanodomains. The cellulose in nanosize can be recovered from the cellulosic biomass by the top-down technique involving various physical and chemical processes followed by refining technique. At present, nanocellulose synthesis is an entirely established technique; however, it involves harsh chemical treatments that are perpetually hazardous to humans and the environment. Various green techniques for nanocellulose synthesis have been proposed such as enzymatic hydrolysis, ionic liquid, and so forth. Although nanocellulose is derived from cellulose, it possesses completely diverse characteristics from original materials. It shows enhanced crystallinity, high surface area, rheological properties, alignment and orientation, biodegradability, biocompatibility, low toxicity, and so on. Nanocellulose has gained much attention for various biochemical applications due to its remarkable physical properties, exceptional surface chemistry and superb biological properties. Its biomedical applications include wound dressings, drug conveyance, medicinal inserts, tissue building, nourishment, and beautifying agents. Whereas its composite materials applications include preparation of biodegradable plastics, aqueous coating, and materials creation.