Mohamad Ridzwan Ishak

Sugar palm (Arenga pinnata): Its fibres, polymers and composites

Sugar palm (Arenga pinnata) is a multipurpose palm species from which a variety of foods and beverages, timber commodities, biofibres, biopolymers and biocomposites can be produced. Recently, it is being used as a source of renewable energy in the form of bio-ethanol via fermentation process of the sugar palm sap. Although numerous products can be produced from sugar palm, three products that are most prominent are palm sugar, fruits and fibres. This paper focuses mainly on the significance of fibres as they are highly durable, resistant to sea water and because they are available naturally in the form of woven fibre they are easy to process. Besides the recent advances in the research of sugar palm fibres and their composites, this paper also addresses the development of new biodegradable polymer derived from sugar palm starch, and presents reviews on fibre surface treatment, product development, and challenges and efforts on properties enhancement of sugar palm fibre composites.

Development and characterization of sugar palm starch and poly(lactic acid) bilayer films.

The development and characterization of environmentally friendly bilayer films from sugar palm starch (SPS) and poly(lactic acid) (PLA) were conducted in this study. The SPS-PLA bilayer films and their individual components were characterized for their physical, mechanical, thermal and water barrier properties. Addition of 50% PLA layer onto 50% SPS layer (SPS50-PLA50) increased the tensile strength of neat SPS film from 7.74 to 13.65MPa but reduced their elongation at break from 46.66 to 15.53%. The incorporation of PLA layer significantly reduced the water vapor permeability as well as the water uptake and solubility of bilayer films which was attributed to the hydrophobic characteristic of the PLA layer. Furthermore, scanning electron microscopy (SEM) image of SPS50-PLA50 revealed lack of strong interfacial adhesion between the SPS and PLA. Overall, the incorporation of PLA layer onto SPS films enhances the suitability of SPS based films for food packaging.

Decision making model for optimal reinforcement condition of natural fiber composites

Natural fiber reinforced polymer composites (NFCs) have recently received much attention as eco-friendly materials due to their desired characteristics such as the high specific properties, low cost, and recyclability features. Achieving an optimal reinforcement condition in NFCs to obtain desired properties is still challenging for both designers and industry. Selecting an appropriate reinforcement condition for natural fiber composites can dramatically enhance achieving better low-cost sustainable design possibilities. Several factors affect acquiring such reinforcement conditions, which make it a matter of multi-criteria decision making (MCDM) problem. This work was able to build and implement DM models in the field of NFCs to optimize the reinforcement conditions for the first time. Here, both Analytic Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) methods were utilized to achieve the optimal reinforcement condition of the date palm/epoxy composite to maximize its overall tensile property considering combined evaluation criteria. Eleven potential reinforcement conditions were evaluated regarding Maximum Tensile Strength (MTS), Maximum Shear Stress (MSS) and Elongation to Break (EL) criteria simultaneously. Experts’ feedback was surveyed to determine both the appropriateness of the evaluation criteria as well as their corresponding weights. MSS has the most contribution in the evaluation process with a weight of 39.0 %, whereas MTS and EL have weights of 31.0 % and 29.0 % respectively. The harmony between AHP and TOPSIS methods in determining the optimal reinforcement condition considering the whole desired evaluation criteria increased its reliability. This work presents a guide and roadmap for implementing proper decision making models in the field of natural fiber composites to optimize their desired characteristics as it is implemented here for the first time.

Predicting the potential of agro waste fibers for sustainable automotive industry using a decision making model

We developed a decision making model to rank natural fiber types for the first time.We predicted and ranked the potential of natural fibers for automotive industry.Flax and date palm fibers are the best choices from wide criteria standpoints.DPF is the best regarding many criteria like Fibers Specific Strength to Cost Ratio.DPF can promote productivity, sustainability and the environmental performance too. Developing a sustainable industry requires proper utilization of the available and compatible natural resources. Selecting a proper natural fiber type to form a reinforced polymer composite suitable for sustainable automotive industry is considered as a multi criteria decision making problem. This work (i) ranks different natural fiber types according to their appropriateness for the sustainable automotive industry using a decision making technique for the first time. (ii) Predicts the potential of the date palm fiber (DPF) as a reasonable cheap alternative for the sustainable automotive industry. A combined informative/expert-feedback decision making model utilizing the analytical hierarchy process (AHP) was built to rank and predict the potential of the natural fibers. This model can optimize finding the most appropriate available, cheap, eco-friendly alternative material to enhance not only the sustainability and productivity of the automotive industry but also the environmental performance too. A pilot questionnaire was conducted to ensure the appropriateness of the used model. The natural fiber options considered were: coir, date palm, flax, hemp and sisal. The flax fiber type is the best choice for automotive applications as it ranks highest, followed by the date palm fiber as a reasonable competitive cheap alternative choice. This decision was made based on simultaneous technical and economic standpoints. Date palm fiber was found to be the best choice regarding many criteria like Fibers Specific Strength to Cost Ratio one. Results demonstrated that the most AHP model priority stack was occupied by both Mechanical Properties and Specific Performance for Automotive Applications criteria. Sensitivity analysis illustrated the reliability of the results and the drawn judgments in this study.

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.

Mechanical properties of kenaf bast and core fibre reinforced unsaturated polyester composites

Kenaf fibre has high potential to be used for composite reinforcement in biocomposite material. It is made up of an inner woody core and an outer fibrous bark surrounding the core. The aim of this study was to compare the mechanical properties of short kenaf bast and core fibre reinforced unsaturated polyester composites with varying fibre weight fraction i.e. 0%, 5%, 10%, 20%, 30% and 40%. The compression moulding technique was used to prepare the composite specimens for tensile, flexural and impact tests in accordance to the ASTM D5083, ASTM D790 and ASTM D256 respectively. The overall results showed that the composites reinforced with kenaf bast fibre had higher mechanical properties than kenaf core fibre composites. The results also showed that the optimum fibre content for achieving highest tensile strength for both bast and core fibre composites was 20%wt. It was also observed that the elongation at break for both composites decreased as the fibre content increased. For the flexural strength, the optimum fibre content for both composites was 10%wt while for impact strength, it was at 10%wt and 5%wt for bast and core fibre composites respectively.

Effect of Alkali and Silane Treatments on Mechanical and Fibre-matrix Bond Strength of Kenaf and Pineapple Leaf Fibres

Natural fibres are very versatile materials, their properties vary with chemical composition and physical structure. The effects of alkali, silane and combined alkali and silane treatments on the mechanical (tensile), morphological, and structural properties of Pine Apple Leave Fibres (PALF) and Kenaf Fibres (KF) were investigated with the aim to improve their compatibility with polymer matrices. The effectiveness of the alkali and saline treatments in the removal of impurities from the fibre surfaces was confirmed by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared spectrometry (FTIR) observation. The morphological study of treated PALF and KF by SEM indicates that silane treated fibres have less impurities and lignin and hemicelluloses removed than those by other chemical treatments. Silane treated PALF and KF display better tensile strength than those of untreated, alkaline and NaOH-silane treated. Droplet test indicates that the Interfacial Stress Strength (IFSS) of alkali and silane treated PALF and KF are enhanced whereas silane treated fibres display highest IFSS. It is assumed that fibre treatments will help to develop high performance KF and PALF reinforced polymer composites for industrial applications.

Alkali Treatment of Screw Pine (Pandanus Odoratissimus) Fibers and Its Effect on Unsaturated Polyester Composites

Characteristics of Screw Pine fiber of species Pandanus Odoratissimus (PO fibers) and short PO fibers reinforced composite were studied. The results show that various alkali concentrations changed ability of PO fibers in absorptions of moisture, chemical compositions and cross-sectional area. The untreated and treated PO fibers were compounded with unsaturated polyester to evaluate their mechanical properties. The treated PO fiber composites exhibit high mechanical properties in comparison with untreated ones. SEM photographs revealed a different fracture surface between untreated PO fiber-reinforced composites and treated ones.

A Model for Evaluating and Determining the Most Appropriate Polymer Matrix Type for Natural Fiber Composites

The process of determining the proper polymer matrix type, using a wide range of criteria, to form a natural fiber–reinforced polymer composite is still not established enough. This work introduces, for the first time, a model to select the proper polymer matrix type for natural fibers to enhance the sustainability of the automotive industry. The model was developed to rank different polymers and to determine their relative merits considering 20 different criteria simultaneously, including different physical, mechanical, chemical, environmental, and technical criteria. This work can support establishing a road map for proper selection of polymers in different engineering applications as well as increasing the reliability of the polymer selection process.

Mechanical properties and fabrication of small boat using woven glass/sugar palm fibres reinforced unsaturated polyester hybrid composite

In recent years, sugar palm fibre has been found to have great potential to be used as fibre reinforcement in polymer matrix composites. This research investigates the mechanical properties of woven glass/sugar palm fibres reinforced unsaturated polyester hybrid composite. The composite specimens made of different layer of fibres such as strand mat, natural and hand woven of sugar palm fibres. The composites were fabricated using a compression moulding technique. The tensile and impact test was carried out in accordance to ASTM 5083 and ASTM D256 standard. The fibre glass boat is a familiar material used in boat industry. A lot of research on fabrication process such as lay-up, vacuum infusion mould and resin transfer mould has been conducted. Hybrid material of sugar palm fibre and fibre glass was used in fabricating the boat. This research investigates the method selection for fabrication of small boat application of natural fibre composites. The composite specimens made of different layer of fibres; woven glass fibre, strand mat, natural and hand woven of woven sugar palm fibres were prepared. The small boat were fabricated using a compression moulding and lay up technique. The results of the experiment showed that the tensile strength, tensile modulus, elongation at break value and impact strength were higher than the natural woven sugar palm fibre. The best method for fabricating the small boat was compression moulding technique. As a general conclusion, the usage of glass fibre had improved the tensile properties sugar palm fibre composites and compression moulding technique is suitable to be used in making a small boat application of natural fibre composites.