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This work reports the influence of various treatments of pineapple leaf fibers (PALF) reinforced tapioca biopolymer (TBP) on the tensile properties. Three different treatments were selected, such as maleic anhydride polypropylene (MAPP) compatibility, maleic anhydride polyethylene (MAPE) compatibility and alkali treatment. Samples with 10% of PALF composition with different concentrations of MAPP and MAPE (1%, 3%, 5% and 7% by weight) and samples with three different treatments were prepared with different PALF compositions (10%, 20%, 30% and 40% by weight). Results revealed that PALF–TBP with 7% of MAPP showed the highest tensile strength and good interfacial adhesion with the matrix as evidenced by the Scanning electron microscopy analysis. Moreover, the chemical analysis by Fourier transforms infrared spectroscopy demonstrated that the MAPP had improved the PALF compatibility and matrix interfaces. Findings suggested that PALF–TBP composites have a great potential to be used for products in engineering applications.

Gun powder is predicted to be more expensive in relation to the world oil shortage crisis in the future. However, cellulose (generic chemical formula (C6H10O5) is the carbohydrate that makes up the main structure of plants. It is more economical especially for countries with a lot of natural resources and rain forests like Malaysia. The finding of the study reveals the capability of nitrocellulose as gunpowder. In this research, a comparison of the same mass of nitrocellulose and gunpowder is made to find out which propellant produce longer distance and greater impact. The main objectives of this study are to find out the performance and capability of nitrocellulose extracted from Rhizophora apiculata compared to gunpowder in terms of velocity, calorific value of bullets and kinetic energy produced. The result shows that the nitrocellulose has better performance than gun powder. The new application of smokeless gun powder ensures troops especially snipers hardly being detected by enemy and at the same time improves safety and security level.

Pulp and paper production from wood material as their main resources have a total capacity about more than one million tons per year. Malaysia has a high scale of deforestation based on the main resource for pulp and paper-based industry. Malaysia as its rate is accelerating faster than any other tropical countries in the world. This problem also affects the economic losses of some countries that face deforestation. To overcome this, Napier grass as a substitute material from non-wood material had been choose for pulp and papermaking industry. This study through the full fibre analysis and morphological characterization, pulpability at kappa number via soda-AQ pulping and the characteristic. These conclude that Napier grass had a high percentage of pulp yields; with a low screening rejects; good mechanical properties by TAPPI method. Thus, Napier grass has a potential to be substitute material for becoming waste-wealth product especially for Malaysia’s pulp and papermaking industry.

Significant improvements in terms of bandwidth of reflectarray antennas have been achieved by introduction of innovative paper substrate dielectric materials. Three differently custom composed organic dielectric substrates have been characterized for dielectric properties using a broadband technique based on open ended coax cable method. The substrates show low dielectric permittivities of 1.81, 1.63 and 1.84 along with a loss tangent of 0.053, 0.047 and 0.057. Validation of using the proposed substrates for reflectarray antenna was done by modelling and fabricating reflectarray unit elements on the three substrates. Scattering parameter analysis of unit reflectarray elements show encouraging results with a broadband frequency response of 340 MHz at a phase gradient of 0.14º/MHz. Thus the proposed substrate could serve exceptionally to address the narrow bandwidth problem in reflectarray antennas.

This paper presents novel loss quantization of reflectarray elements based on organic substrate materials. Three differently composed substrate materials derived from recycled materials have been characterized for their dielectric properties using a broadband analysis technique. The materials show low dielectric permittivity values of 1.81, 1.62 and 1.84 for X-band frequency range. In order to estimate the reflection loss of for the three substrates a mathematical relation has been established using empirical data generated by computer simulated models. The reliability of the proposed model has been established by simulation and fabrication of unit reflectarray rectangular patch elements on three proposed substrate substrates. A broadband frequency response has been depicted by scattering parameter analysis of unit elements with 10% fractional bandwidth of 312, 340 and 207 MHz for RCP50, RCR75 and RNP50 substrate respectively

The effects of beating on the characteristics of pulp and paper derived from durian rind under chemi-mechanical pulping (CMP) method were investigated. All process and characteristic tests were conducted according to Malaysian International Organization for Standardization (MS ISO) and Technical Association of the Pulp and Paper Industry (TAPPI). The unbeaten durian rind CMP pulp (control pulp) was beaten by using PFI mill at three (3) different beating levels; 1000, 2000 and 3000 revolutions. It was found that durian rind CMP pulp drainage time was increased (longer time) and freeness level was decreased as the beating revolutions were increased compared to the control pulp. The result shows that paper bulk density and overall mechanical characteristics (tensile index, tear index, burst index and folding no.) of 60 gsm durian rind CMP hand sheets were increased with the increment of beating revolutions.

This study was carried out to investigate the effect of beating process to the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). OPMFS pulp was prepared according to chemical Soda-AQ pulping process. 60 gsm handsheet of oil palm male flower spikes paper were prepared from OPMFS pulp with four different beating times which are 0 revolution, 1000 revolutions, 2000 revolutions and 3000 revolutions. All physical and mechanical characteristics were investigated according to TAPPI and MS ISO standards. The results show that overall physical and mechanical characteristics of POMFS paper were influenced and enhanced by beating process between 0 until 3000 revolutions. This research demonstrate some potential characteristics of palm oil male flower spikes (OPMFS) paper to be investigated as a newly explored non-wood based raw material for papermaking raw material for papermaking.

The effects of bleaching process on the characteristics of pulp and paper produced from durian rind under chemi‑mechanical pulping (CMP) method were investigated. All process and characteristic tests were conducted according to Malaysian International Organisation for Standardization (MS ISO) and Technical Association of the Pulp and Paper Industry (TAPPI). Three (3) stages of peroxide (P‑P‑P) bleaching sequence through the Total Chlorine Free (TCF) bleaching process were applied to the unbeaten and unbleached durian rind CMP pulp. Bleached CMP durian rind pulp drainage time (32s) decreased (faster) and CSF freeness level (172.50ml) increased as compared to a control pulp. It was obtained that overall optical (brightness (66.36 %)) and mechanical characteristics (tensile index (38.33 Nm/g), tearing index (7.56 mN.m2/g), bursting index (2.42 kPa.m2/g), and number of folds (43)) of durian rind CMP 60 gsm paper sheet improved as the TCF bleaching process was applied to the unbleached CMP durian rind pulp.

This study was carried out to investigate the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). The evaluation of the pulping process was studied based on the chemical Soda Anthraquinone pulping process. 60 gsm papersheet of oil palm male flower spikes were prepared from unbeaten and unbleached OPMFS Soda-AQ pulp. All optical, physical and mechanical characteristics were investigated according to TAPPI and MS ISO standards. OPMFS pulp recorded value of 6.42 s, 353 ml, 76.5 %, 36.7 % and 9.35 for drainage time, freeness, moisture content, screened yield percentage and Kappa number respectively. OPMFS paper sheet recorded value of 56.99 g/m2, 131.11 µm and 0.43 g/m3for grammage, bulking thickness and apparent bulk density respectively. Unbleached OPMFS paper also recorded 26.49 % and 43.50 % for brightness and opacity. For mechanical characteristics, OPMFS paper recorded 39.10 N.m/g, 8.32 mN.m2/g, 3.15 kPa.m2/g and 38.50 for tensile index, tear index, burst index and folding endurance (no.) respectively. This research demonstrate some potential characteristics of oil palm male flower spikes (OPMFS) paper to be investigated as a newly explored non-wood based raw material for papermaking.

This article presents an analysis of reflection loss and reflection phase behavior of a novel microstrip reflectarray antenna, embedded on paper substrate material. Two different paper substrates were first analyzed for dielectric material properties. A detailed analysis of scattering parameters of rectangular patch element with variable substrate heights has been carried out. Rectangular patch elements fabricated using adhesive copper tape over the paper substrate, show that a wide bandwidth is achieved compared to available conventional substrate materials. Fabricated patch elements over paper substrate material show a broadband frequency response of 340 and 290 MHz. It has also been demonstrated that the measured reflection phase ranges for both the substrate cover 310º and 294º at low phase gradients of 0.12 and 0.24 º/MHz respectively.

This paper presents an analysis of reflection phase of reflectarray antenna based on high loss organic substrate material. Paper substrate material derived from recycled materials was characterized for dielectric material properties. The material shows excellent dielectric material properties with permittivity of 1.63 and loss tangent of 0.048. Effect of substrate height variation over the reflection phase has been discussed. Full wave analysis of the simulated model depicts that the reduction in substrate height after a certain point results in reflection phase distortion of reflectarray element. Validation of the results has been done by simulation, fabrication and scattering parameters measurements of a rectangular patch element on proposed substrate material. The results show a broadband frequency response of 355 MHz and a phase range of 301º at a phase gradient of 0.14 º/MHz.

This paper presents novel loss quantization of reflectarray elements based on organic substrate materials. Three differently composed substrate materials derived from recycled materials have been characterized for their dielectric properties using a broadband analysis technique. The materials show low dielectric permittivity values of 1.81, 1.62 and 1.84 for X-band frequency range. In order to estimate the reflection loss of for the three substrates a mathematical relation has been established using empirical data generated by computer simulated models. The reliability of the proposed model has been established by simulation and fabrication of unit reflectarray rectangular patch elements on three proposed substrate substrates. A broadband frequency response has been depicted by scattering parameter analysis of unit elements with 10% fractional bandwidth of 312, 340 and 207 MHz for RCP50, RCR75 and RNP50 substrate respectively.

Acacia mangium, a fast growing tree is widely planted in Malaysia. Converting Acacia wood into nanocellulose could create new value added products for forest-based industry. Nanocrystalline cellulose (NCC) was prepared from Acacia mangium wood pulp via 64 wt% sulfuric acid hydrolysis. Prior to acid hydrolysis, Acacia mangium was subjected to pulping followed by bleaching in order to remove non-cellulosic fragments. Acid hydrolysis was carried out on bleached pulp to produce the needle-like NCC with 79% crystallinity and aspect ratio of 26. The resulting NCC was mixed with PVA as a reinforcement material. Incorporation of 2% NCC improved the tensile of the NCC-PVA film by 30%.

In recent years, there has been tremendous growth of interest in the utilization of non-wood based material to support the insufficient raw materials availability for the pulp and paper industry. Therefore, this study was conducted to investigate the characteristics of 120 gsm linerboard and corrugated medium paper made from unbeaten durian rinds chemi-mechanical (CMP) pulp. The linerboard and corrugated medium paper were prepared and tested according to Malaysian Standards / International Organization for Standardization (MS ISO) and Technical Association of the Pulp and Paper Industry (TAPPI) standard methods. Based on the burst index (2.03 kPa.m 2 /g), RCT (1.97 N.m 2 /g) and CMT (129N), the linerboard and corrugated medium from CMP durian rind pulp have shown a good potential as an alternative raw material for papermaking and comparable with other types of wood and non-wood based papers as well as current commercial papers.

Membrane distillation (MD), a thermally-driven membrane separation process has been widely studied in recent years and the membrane properties are known to have significant effect on the performance of the MD process. This paper studied the microstructure of PTFE membranes from three different sources for MD application. The parameters investigated include pore size, thickness, porosity and tortuosity. Non-supported membranes were also tested for comparison. The experimental results for different pore size, thickness, porosity, tortuosity and support materials in direct contact membrane distillation (DCMD) were compared with the theoretical flux simulated from the Schofield model using Polymath NLE solver. The temperature polarisation coefficient was also determined to establish the relationship between the membrane microstructure and performance. The results indicated that the structure and porosity of support materials play important roles in determining the performance of DCMD. Higher fluxes and lower temperature polarisations were observed over membranes with large pore size, low thickness, high porosity and low tortuosity. Membrane porosity, pore size and the presence of support materials were found to have significant effects on flux and temperature polarisation.

This paper presents three novel substrate materials with efficient dielectric characteristics. Different types of innovative substrate materials used for microwave electronics have been discussed. It has been demonstrated that the repeatability of results for paper substrate based electronics can be maintained using the proposed substrate materials. Three different substrate materials derived from recycled sources such as newspaper, copier paper and carton paper and banana pulp have been presented. The paper substrates were manufactured and processed to reduce the moisture content that might degrade the performance. A broadband dielectric material characterization of the proposed substrate shows a stable electromagnetic behaviour over the X – band operation with relative permittivities of 1.81, 1.63 and 1.84 along with loss tangents of 0.053, 0.046 and 0.057 respectively.

Good combination of pulping variables is required to obtain the quality pulp and paper characteristics. Thus, in this preliminary work, naturally dried durian rind were pulped under Soda-Anthraquinone (Soda-AQ) pulping process with 18% to 22% alkali charge, 0% to 0.1% Anthraquinone (AQ) charge, 90 minutes to 150 minutes of cooking time and 150°C to 170°C to investigate the effect of pulping variables on the characteristics of the pulp and paper. Pulping condition with 0% of AQ charge was also conducted for comparison. Results indicated that the best screen yield percentage, reject yield percentage, freeness, drainage time, tear index, number of folds and optical properties were shown by the pulp produced with combination of the highest active alkali (22%), AQ charge (0.1%), cooking time (150 minutes) and cooking temperature (170°C) except apparent density, tensile index and burst index. This preliminary result shows that the optimum quality of durian rind pulp as a potential papermaking raw material pulp could be produced by selecting the good combination of pulping variables which influences the pulp and paper characteristics.

A preliminary test was conducted to investigate the characteristics of linerboard and corrugated medium paper made from durian rind waste. Naturally dried durian rinds were pulped according to Soda-Anthraquinone (Soda-AQ) pulping process with a condition of 20% active alkali, 0.1% AQ, 7:1 liquor to material ratio, 120 minutes cooking time and 170°C cooking temperature. The linerboard and corrugated medium paper with a basis weight of 120 gsm were prepared and evaluated according to Malaysian International Organization for Standardization (MS ISO) and Technical Association of the Pulp and Paper Industry (TAPPI). The results indicate that the characteristics of durian rind linerboard are comparable with other wood or non-wood based paper and current commercial paper. However, low CMT value for corrugated medium and water absorptiveness quality for linerboard could be improved in future. Based on the bulk density (0.672 g/cm3), burst index (3.12 kPa.m2/g) and RCT (2.00 N.m2/g), the durian rind has shown a good potential and suitable as an alternative raw material source for linerboard industry.

The physical, optical and mechanical characteristics of pulp and paper made from waste durian rinds as an alternative raw material for papermaking were investigated according to TAPPI and MS ISO standards. The durian rinds pulp was produced through chemi-mechanical pulping (CMP). Naturally dried durian rinds were treated with 10% Sodium Hydroxide (NaOH) based on oven dry (o.d) weight of durian rinds in room temperature for 2 hours and pulped by the refiner mechanical pulping (RMP) process. Experimental results show that durian rinds have great potential characteristics as newly explored non-wood based raw material for pulp and paper industry.

This study explores the benefits of using Amphoteric PAM (aPAM) and Cationic PAM (cPAM) as a dry strength agent in coir based paper. The aPAM and cPAM were incorporated to coir pulp slurry in different dosages (0.5% - 2.0%) during stock preparation. Industrial grade of potassium aluminum sulfate (alum) was used for all sets handsheet. For each treatment, 12 handsheets, each having basis weight of 120 g/m 2 were made. The results showed that the utilization of cPAM had better drainage compared to the aPAM for all treatment. In general, the apparent density and strength properties were significantly affected by the addition of dry strength agents. The enhancing effect of aPAM on strength properties of coir paper was much higher than using cPAM except for ring crush test (RCT) and concora medium test (CMT).