Wei Chen Lum

University of Malaysia, Kelantan | UMK · Faculty of Bioengineering and Technology

This book highlights the world distribution of eucalyptus plantations and the recent state of research on the utilization of planted eucalyptus for engineered wood products (EWPs) manufacturing. EWPs such as particleboard, fiberboard, oriented strand board, laminated veneer lumber, plywood, glue-laminated lumber, and cross-laminated lumber are high...

Using CaCl2-H2O2 as the initiator, hydrophobic tannin-acrylic resin (TA) was prepared by grafting acrylic monomers onto tannins through redox reaction. Subsequently, biodegradable TA-polyvinyl alcohol (PVOH) hydrophobic film (TAP) was prepared by blending TA with PVOH at room temperature. The results of Fourier transform infrared spectroscopy (FT-I...

Wood-based materials, such as medium-density fiberboard (MDF) and oriented strand board (OSB), are increasingly being used in a variety of applications due to their unique properties and environmental benefits. MDF is made from wood fibers that are bonded together with a synthetic resin, whereas OSB is made from wood strands that are oriented in sp...

The adoption of limit state design according to Eurocode 5 (EC5) has brought about design strength optimisation in design practices worldwide. However, the implementation of EC5 may not be suitable for Malaysian tropical timber species as the design strength data in European Standard (EN) 338:2016 is based on softwood and temperate hardwood species...

Thirteen bamboo species are reported to be in commercial use in Malaysia. However, Buluh madu (Gigantochloa albociliata) did not make to the list. As a species, G. albociliata is cultivated for its delicious bamboo shoot and is demonstrated to possess great potential to produce commercialised products such as laminated bamboo panel. Unlike common b...

The design practice has shifted from permissible stress design to limit state design using Eurocode 5 (EC5), which introduces design strength optimization. However, the adoption of EC5 in Malaysia cannot be done directly due to the absence of design strength data for Malaysian timber species. This paper presents a study that evaluates the bending s...

In this study, the effects of resin and wax content as well as board density on the modulus of rupture (MOR) and internal bonding (IB) and thickness swelling (TS), were investigated. Three-layer particleboard was made with rubberwood particles. Different urea formaldehyde (UF) resin contents (%) were applied on the surface/core/surface layer of the...

The initial moisture content (MC) and conditioning environment are among the most important factors that affect the properties as well as formaldehyde emission of particleboard. In this study, a three-layer rubberwood particleboard bonded with urea formaldehyde (UF) resin was prepared. Fine and coarse rubberwood particles with initial MC (of 3, 5,...

Theapplication of laminated veneer lumber (LVL) has long been limited to non-structural elements in Malaysia.LVL is commonly fabricated with veneer from low to medium density (290 to 630 kg/m3)softwood or temperate hardwood. The data on the properties of LVL made from medium to high density (567 to 687 kg/m3)tropical hardwood species is very limite...

Palms belong to one of the largest plant families, Arecaceae. They are among the most extensively cultivated species used for foods and landscaping. This family covers a large variety of species and is widely distributed in warm and humid lowlands of the tropics. Malaysia, which is located in the equatorial region with a typical tropical climate, i...

Many real-scale fire tests have been performed on timber connections to analyze the mechanical behavior of timber connections in previous years. However, little research focused on the bending performance of glued laminated (glulam) timber beam bolted connections after fire exposure. In this paper, the three-dimensional numerical model of the glula...

Over the last 50 years, the use of wood adhesives in the manufacturing of wood-based panel goods has increased the efficiency of wood resources. Wood adhesives are becoming more popular as the need for wood-based panels grows. By 2028, the global market for wood adhesives is expected to reach 21.8 billion dollars. Even though urea-formaldehyde (UF)...

Due to thermal and flame/fire sensitivity of biopolymers especially in plant-based biopolymer fillers, it is extremely and necessary to improve the reaction to flame. The bio-polymers currently are used in many applications and daily life products and due to the potential risks of its tendency to burn and widespread the flames. To overcome these ri...

The use of alternative raw materials such as agricultural biomass and recycled wood waste and by-products in particleboard production is a viable approach to respond to the increased global demand for wood-based materials, and it is a key circular economy principle as well. Wood chips are the second most costly element after resin in particleboard...

The design practice of timber structures in Malaysia is still based on permissible stress codes as stated in Malaysian Standard (MS) 544: Part 2 and MS 544: Part 3, which was adopted from the British Standard (BS) 5268. The British Standard was later completely replaced by Eurocode 5 (EC5) in 2009. Therefore, to preserve the continuity of design co...

Cross laminated timber (CLT) is acknowledged to be a high-performance composite material used in the construction industry. The manufacturing of CLT in temperate countries is well established and has been proven to have high mechanical properties compared to solid wood. However, to date, the production of CLT from tropical hardwood is still not ava...

In order to develop shear strength data for limit state design as stated in Eurocode 5, the strength properties need to be determined using large size structural specimens. However, the specific data for Malaysian tropical hardwood were not available for the moment. Thus, shear strength parallel to the grain for structural specimens from seven Mala...

Forest covers 4.06 billion hectares (ha) or 31% of the total land area worldwide, where 93% (3.75 billion ha) are natural regenerating forests and the remaining 7% (294 million ha) are planted forests. Eucalyptus spp., being one of the most important plantation species, has been planted in 95 countries around the world, and the area of plantation h...

Forest covers 4.06 billion hectares (ha) or 31% of the total land area worldwide, where 93% (3.75 billion ha) are natural regenerating forests and the remaining 7% (294 million ha) are planted forests. Eucalyptus spp., being one of the most important plantation species, has been planted in 95 countries around the world, and the area of plantation h...

Cross laminated timber (CLT) is known as a composite material that possesses high-performance properties. As an engineered timber product, it has been proven that CLT has better properties in terms of its strength compared to solid sawn timber. However, the strength of this product is influenced by its bonding integrity. To date, the production and...

Cross-laminated timber (CLT) is one of the preferred engineered timber products (ETP) used in the construction and building industry. CLT is an orthogonal and laminar structure that can be used as full-size load-bearing structural elements such as wall, floor element as well as a linear timber member. The timber pieces are visually graded before be...

White-rot fungi (Pycnoporous sanguineus) and subterranean termites (Coptotermes curvignathus) are the two most important biodeterioration agents found in tropical countries such as Malaysia that cause severe damage to wood. White-rot fungi are the only microorganisms known to efficiently degrade all the components of wood, including lignin (Shary e...

Particleboard is one of the major timber products in Malaysia. Previously, rubberwood is the main raw material for particleboard production. However, due to the declining rubberwood plantations in the country, oil palm biomasses have been found to be a suitable alternative. Oil palm trunk (OPT), oil palm frond (OPF), and empty fruit bunch (EFB) hav...

Oil palm, rubber, rice, cocoa, and coconut are the main agricultural commodities grown in Malaysia. According to Griffin et al. (2010), 17 Mt of agricultural residues have been estimated. More than three-third of these residues are dominated by oil palm, while the remaining consists of rice, forestry, and other residues such as rubber, cocoa, and c...

This study investigated the bending, compression as well as the bonding performance of CLT panels made from fast-growing timber species, i.e., Laran (Neolamarckia cadamba) and Batai (Paraserianthes falcataria). The variables studied were timber species (Laran and Batai), layers of lamination (3-layer and 5-layer), loading direction in bending (in-p...

Forest covers 4.06 billion hectares (ha) or 31% of the total land area worldwide, where 93% (3.75 billion ha) are natural regenerating forests and the remaining 7% (294 million ha) are planted forests. Eucalyptus (Eucalyptus spp.), being one of the most important plantation species, has been planted in 95 countries around the world, and the area of...

The study investigated the effects of the addition of starch on the properties of oil palm biomass particleboard bonded with citric acid. Three kinds of oil palm biomasses were used in this study for the fabrication of particleboard, namely, oil palm frond (OPF), oil palm trunk (OPT), and empty fruit bunch (EFB) particles. Citric acid and tapioca s...

Natural rubber is of significant economic importance owing to its excellent resilience, elasticity, abrasion and impact resistance. Despite that, natural rubber has been identified with some drawbacks such as low modulus and strength and therefore opens up the opportunity for adding a reinforcing agent. Apart from the conventional fillers such as s...

The scarcity of good quality timber initiates the timber industry shift to engineered timber products. Laminated veneer lumber (LVL) promising high strength and more dimensionally stable as well as flexible compared to conventional timber components. However, most of the previous studies focus on softwood timber, and limited species utilized tropic...

Owing to their versatility in a wide range of applications, polymer-based composite has become a popular material in replacing metal alloys. Incorporation of nanoparticles is one of the effective methods in enhancing the performance of the polymeric composite materials. Nanoclay (nC) is one of the prevalent reinforcing agents attributed to their we...

Citric acid (CA) can be found naturally in fruits and vegetables, particularly citrus fruit. CA is widely used in many fields but its usage as a green modifying agent and binder for wood is barely addressed. Esterification is one of the most common chemical reactions applied in wood modification. CA contains three carboxyl groups, making it possibl...

Urea formaldehyde-bonded particleboard made from oil palm trunk (OPT) and rubberwood (RW) were soaked in palm oil for 24 hr before thermally treated in oven at 180°C, 200°C and 220°C. Colour changes and decay resistance against white rot fungus (Pycnoporus sanguineus) of the samples after thermal treatment were investigated. After thermal treatment...

Nanomaterials are defined as materials that possess at least one of the external dimensions or internal structure within the size range of 1–100 nm. Over the past few years, nanotechnology and nanomaterials have been identified as potential tools in agricultural sector to regulate plant growth and improve its genetics as well as its use as pesticid...

In designing timber structures based on Eurocode 5, the referencestrength data are given in EN338 where the data are formulated from testing structural size specimens. Malaysian standard established strength grouping using grade stresses based on small clear specimens where as in EN 338 is in characteristic strength. . Therefore, it’s important to...

Pineapple leaf fibers (PALF) are very suitable to act as reinforcing composite matrixes. Nevertheless, PALF is highly susceptible to the risk of fire hazard. Therefore, priority is often being placed in order to improve the fire retardancy of the PALF and its composite products. This chapter discusses the behavior of natural fibers in fire and vari...

Semantan bamboo (Gigantochloa Scortechinii) was hydrothermally treated in three different buffered media, namely alkaline, neutral and acidic medium. Response surface methodology (RSM) models were developed for the influences of treatment temperature, treatment duration and pH of buffered media on dimensional stability of Semantan bamboo. The model...

This study investigates the physical and biological properties of urea formaldehyde (UF)- and citric acid-bonded particleboard. Furfuryl alcohol and palm oil were added into both UF and citric acid in order to enhance the properties of the produced particleboard. Particleboard bonded with 4 different types of binder were tested for thickness swelli...

This research investigated the behaviour of walls produced from wood wool cement board (WWCB) which were reinforced with a lesser known commercial timber, Kelempayan, when subjected to compression load. Kelempayan timbers were shredded into wood wool and used as reinforcement agent in this study. WWCB having dimensions of 600 × 2400 × 50 mm and 600...

Wood is an ideal building material as it is renewable and green. However, low dimensional stability and durability might restrict its usage in structural application. Therefore, modification is needed to improve the aforementioned issues. As an environmentally friendly wood modification method, heat treatment of wood using oil as a heating medium h...

Chemical, thermal properties, surface characteristics, termite resistance and physico-mechanical properties of urea formaldehyde-bonded oil palm trunk particleboard post heat-treated in palm oil were investigated. Oven dried samples were immersed in palm oil for 24 h prior to expose to temperature of 180, 200 and 220 °C in a laboratory oven for 2 h...

Production of green composites involve a manufacturing process that combining both renewable plant-based particles and green polymers. Characteristics of wood and non-wood particles are one of the main factors that influencing the properties of green composite, particularly particle based composite i.e., particleboard and wood plastic composite (WP...

Mechanical properties of finger joints made from eight Malaysian tropical hardwood species were investigated in this study. The wood species studied were merpauh (Swintonia spp.), kapur (Dryobalanops spp.), resak (Cotylelobium spp.), white meranti (Shorea spp.), bintangor (Calophyllum spp.), jelutong (Dyera spp.) sesendok (Endospermum spp.) and kel...

Rubberwood particleboard were produced using urea formaldehyde (UF) resin admixed with propylamine as formaldehyde scavenger. 1 % propylamine were incorporated into 8 %, 10 %, 12 %, 14 % and 16 % UF resins, respectively. The effectiveness of propylamine addition to reduce formaldehyde emission from particleboard was examined. Physical and mechanica...

Gypsum boards had poor dimensional stability and mechanical properties compared to cement boards. To improve its properties, gypsum–cement boards reinforced with kenaf fibre bast using different gypsum/cement mixing ratios was fabricated in the current study. The results revealed that addition of cement generally improved the bending strength and c...

The chemical properties, dimensional stability, mechanical strength and termite resistance of urea formaldehyde (UF) bond rubberwood (RW) particleboard (PB) were assessed after a two-step oil heat treatment (OHT). The PB was immersed in palm oil before heating to 180, 200, and 220°C in a laboratory oven for 2 h. Anti-swelling efficiency (ASE) and w...

The objective of the study was to investigate the effect of heat treatment on the changes in density profile of rubberwood particleboard samples. The relationship between density profile and mechanical properties of particleboard samples was determined using regression analysis. Single layer particleboard made from rubberwood particles with dimensi...

The first occurrence of Lace bug, Cochlochila bullita Stål, was recorded in Malaysia in year of 2010. Description of this species was made. Damage on Ocimum basilicum and Orthosiphon aristatus caused by Cochlochila bullita Stål was investigated in this study. Symptoms of the infested plants were also described. Possible control method against this...

Ocimum tingid, Cochlochila bullita Stål (Hemiptera: Tingidae) is a pest of Lamiaceae plants, such as basil, tulsi and coleus. It is now been recorded in Malaysia as a pest of the cat’s whiskers plant, Orthosiphon aristatus (Blume) Miq. Nevertheless, apart from its brief biological description, no other information is available. The life table of th...

The usage of high ash content biomass for heat and electricity generation may lead to various ash-related problems, primarily to heating value, ash and combustion characteristics. The study aims at studying the effectiveness of leaching on removing ash forming elements and increasing ash melting temperature using water and acetic acid as the extrac...

Compaction ratio is highly dependent on the density of the wood materials used in the production of particleboard. Lower density wood materials will produce particleboard with higher compaction ratio and is believed to give better properties. The objective of this study was to evaluate the properties of three-layer particleboard made from rubberwoo...

This study aims at evaluating the effects of heat treatment on microstructural, mechanical and physical properties of experimentally manufactured particleboard from rubberwood. Two types of heating methods, namely oven and hot press, were used in this study. Samples of the particleboard were heat-treated at six levels of temperature (100, 120, 140,...

Compaction ratio is highly dependent on the density of the wood materials used in the production of particleboard. Lower density wood materials will produce particleboard with higher compaction ratio and is believed to give better properties. The objective of this study was to evaluate the properties of three-layer particleboard made from rubberwoo...

The demand of renewable energy had created a foundation for biofuels to grow. Bio oil as secondary biofuels is produced from pyrolysis process using biomass as feedstock. The quality of bio oil mainly calorific value (high heating value) affected by the process temperature and solid residence time during pyrolysis. In this study, the effect of pyro...

At present, empty fruit bunch (EFB) is used particularly as a substitute for wood fiber in few industries. Nevertheless, the end products have been reported to be relatively inferior to those made from wood and performed below the par. This chapter provides a platform to delve into the unseen keys and real facts of EFB in renewable energy, derivati...

Development time, survival rate and fecundity of Pteroma pendula fed on three different host trees, Acacia mangium, Callerya atropurpurea and Cassia fistula, were determined in the laboratory. A cohort of 100 eggs (n = 100) were used for each host trees. Mortality and development time from eggs to adult were recorded and the fecundity was obtained...

Termites thrive in great abundance in terrestrial ecosystems and the symbiotic gut microbiota play important roles in digestion of lignocelluloses and nitrogen metabolism. Termites are excellent models of biocatalysts as they inhabit dense microbes in their guts that produce digestive enzymes to decompose lignocelluloses and convert it to end produ...

Rapid price increases and reduction in the supply of rubberwood has forced the particleboard manufacturers to look for new alternative raw materials. The production of particleboard from other wood species will be a good solution to the problem of depleting wood supplies. The objective of this study was to evaluate the properties of particleboard m...

Formaldehyde catcher is a chemical compound that reacts with formaldehyde to form a less harmful product. Various compounds and methods of application have been found effective to reduce formaldehyde emission. The objective of this study was to reduce the formaldehyde emission of particleboard by applying post-treatment formaldehyde catcher. In thi...

One species of lace bug Cochlochila bullita Stål (Heteroptera: Tingidae) was found heavily infested Orthosiphon aristatus Blume Miq., an important medicinal plant in Malaysia. A morphological re-description of C. bullita was done in order to facilitate the identification of this oligophagous insect pest. Five variables, body length and width, anten...

The objective of this study is to investigate the feasibility of formaldehyde catcher as termites repellent. Single-layered UF-bonded particleboard was post-treated with formaldehyde catcher and heat respectively. Besides that, some boards were also produced with the formaldehyde catcher was added into the resin during the blending process, called...

The objective of this present study was to propose a post heat treatment as a method to improve particleboard dimensional stability by decreasing wood hygroscopicity and releasing hotpressing stress. Rubberwood panels from rubberwood were treated in a laboratory press at three different temperatures (100, 150 and 180°C) for about 90, 180 and 270 se...

In order to preserve the global market competitiveness, the particleboard industry was affronted with challenges to reduce formaldehyde emission while maintaining the quality strength properties of particleboard. To counter the issue, particleboards with five different surface-to-core ratio were fabricated by applying newly formulated UF and MUF re...

Particleboard is one of the major timber products exported from Peninsular Malaysia. Apparently, the increasing price and lack of supply of rubberwood has forced the particleboard manufacturers to look for new alternative raw material to produce particleboard. Hence, the production of particleboard through mixture of fast-growing wood species will...