Palm Plywood Research Articles

Phenol–urea–formaldehyde resin co-polymer synthesis and its influence on Elaeis palm trunk plywood mechanical performance evaluated by 13C NMR and MALDI-TOF mass spectrometry

This study evaluated a new method of producing phenol–urea–formaldehyde (PUF) adhesives formulated differently under actual “in-situ” resin synthesis conditions. This was carried out by co-polymerizing urea formaldehyde (UF) resin with phenol–formaldehyde resin in the core layer of low molecular weight (LMW) phenol–formaldehyde (PF) resin treated Elaeis palm trunk veneers during the gluing process of Elaeis palm plywood. Matrix assisted laser desorption Ionization time of flight (MALDI-TOF) mass spectrometry (MS) illustrated and confirmed a series number of the phenol–urea co-condensates repeating unit in the prepared PUF resins which corroborated well with its mechanical properties (modulus of elasticity and modulus of rupture), bonding quality (dry test and weather boil proof or WBP test) and physical properties. A series of PF, UF and PUF resins oligomers forming repeating units up to 1833Da were identified. Besides that, the solid state 13Carbon nuclear magnetic resonance (NMR) interpretation identified that the signal at 44–45ppm and 54–55ppm corresponding to methylene bridges were co-condensated in between phenol and urea in the PUF resin system. The 13C NMR investigation showed that the synthesis process of PUF resin contained no free formaldehyde elements. Furthermore, the proportion of urea and methylolureas in the mixture to synthesis PUF resin were sufficient and incorporated well into the formulation by reacting with LMWPF units to form co-condensed methylene bridges. This study showed a new and useful method to synthesize PUF resin during the gluing process of manufactured Elaeis palm plywood which can also enhance the performance of Elaeis palm plywood panels for structural instead of utility grade applications.

LIFE CYCLE ASSESSMENT FOR OIL PALM BASED PLYWOOD: A GATE-TO-GATE CASE STUDY

Life Cycle Assessment (LCA) is an important tool for identifying potential environmental impacts assoc iated with the production of palm based plywood. This study is to make available the life cycle inventory fo r gateto-gate data so that the environmental impact posed by oil palm based plywood production can be assessed. Conducting an LCA on the palm based plywood that are derived from the wastes of the oil palm industry is a first step towards performing green environmental p roduct. Therefore.establishing baseline information for the complete environmental profile of the palm oil plywood is essential. Data from this study on the environmental impact for the production of palm ply wood would help to develop sustainable palm plywood product. The results will provide information to id entify ways and measures to reduce the environmental impacts. Most foreground data were collected direct ly from numbers oil palm plywood factories which represent 40% of the palm plywood industry in Peninsular Malaysia. Data gaps were filled by informatio n obtained through questionnaires which were developed specifically for data collection, literature, pub lic database or further calculated from obtained data. The outputs and inputs from production activities w ere quantified on the basis of functional unit of produ ction of 1 m 3 from different types of oil palm based plywood i.e., Moisture Resistant (MR), Weather Boiling Proo f (WBP) Grade 1 and Weather Boiling Proof (WBP) Grade 2. The life cycle impact assessment was carri ed out using SimaPro 7.1 software and the eco-indic ator 99 methodology. The weighting results of LCA for the production of 1 cubic meter of oil palm based plywoo d showed significant impact in descending order i.e., fossil fuel, respiratory inorganic and climate cha nge. The most significant process contributing to these envi ronmental impacts came from the production and usage of adhesives, transportation of oil palm trunks from p lantation to factory and generation and usage of el ectricity from the grid. The ways to mitigate the environment al impacts are by using substitutes for inorganic c hemical adhesives such as groundnut shell lignin adhesive, modified phenol formaldehyde adhesive and developing wood adhesive made from pyrolisis oil of oil palm b iomass, establishing a collecting centre for oil pa lm trunk transportation and efficient use of oil palm biomas s as an energy source. The study helped establishin g baseline information for the complete environmental profile of the palm oil industry from cradle to gr ave which starts at the oil palm germinated seeds to th e production of palm plywood.

The Improvement in Physical and Static Bending Properties of Woven Oil Palm Plywood

The physical and static bending properties of woven oil palm plywood pre-treated with low molecular weight of phenol formaldehyde (LMWPF) were investigated using MS standard 1787: Part 6 and 10. The oil palm veneers were cut into three different split widths of 15, 20 and 25 mm; and manually woven into veneer sized of 40 cm2. The plywoods were fabricated into three different matrix layers of Type 1 (all three layer contained woven veneers), Type 2 (only core layer contained woven veneer) and Type 3 (face and back layers contained woven veneer). All plywood were made using a urea formaldehyde resin (UF) with spread rate of 200g/m2, pre-pressed for two minutes and hot pressed at 130 °C for 12 minutes. The results revealed that Type 1 plywood gave the lowest thickness swelling, while Type 3 gave the highest static bending properties.

Development a new method for pilot scale production of high grade oil palm plywood: Effect of resin content on the mechanical properties, bonding quality and formaldehyde emission of palm plywood

The main objectives of this research were to investigate the formaldehyde emission, some mechanical properties and bonding quality of oil palm trunk (OPT) plywood treated with low molecular weight phenol–formaldehyde (LmwPF), as affected by resin concentration. The mechanical properties are affected by different of amount resin solid contents used. The OPT veneer were treated at either 40%, 32%, 23% or 15% of resin concentration and 12mm thickness of 3-ply plywood panel were manufactured for each group. In this study the formaldehyde emission, modulus of rupture (MOR), modulus of elasticity (MOE) and bonding quality (shear strength) of OPT plywood were determined. The results revealed that the resin-treatment method was tend to significantly improved the mechanical properties of the OPT plywood panel in which increased solid absorption gives bettermechanical properties. Apparently, high mechanical properties were obtained for panel manufacturer from veneer treated with 32% and 40% resin content. The resin-treated OPT plywood provided superior mechanical strength with improvements at least 202% MOE and 159% MOR compared to commercial OPT plywood. Whereas, mechanical properties of the resin-treated OPT plywood were drastically decrease with increasing the water substitution. Formaldehyde emission content of OPT panels decreased upon reduction of resin content into treatment process and were significant at resin concentration. The resin-treated OPT panels at 32% solid content provided a reasonable amount of free formaldehyde (0.359mg/L) which attained F∗∗∗∗ according to Japanese Agriculture Standard (JAS). The shear strength of resin-treated OPT plywood panel with 32% and 40% resin content achieved minimum requirements according to the standard European Norms EN 314-1 and EN 314-2 for the interior and exterior application.

Development a new method for pilot scale production of high grade oil palm plywood: Effect of hot-pressing time

The main objective in this study were to investigate the physical properties, mechanical properties and bonding qualities of oil palm stem (OPS) plywood pre-preg using low molecular weight phenol–formaldehyde (LmwPF). The properties evaluated were physical properties (resin uptake, weight percent gain), mechanical properties (bending strength) and bonding qualities (dry test, WPB test). The results showed that, the physical properties of OPS plywood were significant at resin concentration and veneer moisture content. Moreover, the mechanical properties and bonding performance of the pre-preg OPS plywood were influenced by the pressing time. The high grade OPS plywood with improved at least 227% MOR and 348% MOE compared to commercial OPS plywood, with greater in MOR (31%) and MOE (12%) higher compared than the commercial tropical mix light hardwood (MLHW) plywood. All the shear strength of pre-preg OPS plywood panel were achieved with their minimum requirements and satisfied all the specific testing based on the standard European Norms EN 314-1 and EN 314-2 for the interior and exterior application purposes. The output of this pilot scale study proved that high performance OPS plywood could produced through pre-preg enhancement method in the current plywood mills in which provides broader area of applications compared with conventional OPS plywood. For instant, the pre-preg OPS plywood which is suitable for structural application, concrete formwork, heavy duty interior structuring board, load bearing plywood, marine grade plywood, was obtained, thus consequently increases the price of OPS plywood panels.

ADHESION CHARACTERISTICS OF PHENOL FORMALDEHYDE PRE-PREG OIL PALM STEM VENEERS

The purpose of this study was to evaluate the adhesion properties of phenol formaldehyde-prepreg oil palm veneers that have potential for plywood manufacture. Phenol formaldehyde (PF) resin of three different molecular weights (i.e. 600 (low), 2,000 (medium), and 5,000 (commercial)) were used to pre-treat the veneers. The veneers were soaked in each type of PF resin for 20 seconds, pressed between two rollers, and pre-cured in an oven maintained at 103 ± 2 °C for 24 hours. The volume percent gain (VPG), weight percent gain (WPG), pH, buffering capacity, and contact angle of the phenolic pre-preg veneers were determined. The bonding shear was also evaluated according to British Standard European Norm BS EN 314. The results show that veneers from both inner and outer layers treated with low molecular weight PF (LMwPF) resin had significantly higher VPG and WPG compared to the other PF resins. The pH values of all of the veneers were slightly acidic (6.5 to 6.8) except for those that were treated with commercial molecular weight PF resin (7.8). A buffering capacity study revealed that untreated veneer had a greater resistance toward alkali, but was unstable under acidic conditions, while the phenolic pre-preg veneer behaved differently. This effect was more prominent as the molecular weight of the PF resin increased. An examination of the veneer surfaces demonstrated that phenolic treatment had increased the contact angle of the OPS veneer surfaces significantly. The bonding properties of plywood made from pre-preg palm veneers were found to be superior to those of commercial palm plywood.

Development of a new pilot scale production of high grade oil palm plywood: Effect of pressing pressure

Nowadays, the use of waste materials such as, saw dust, rice husk, coconut coir, empty fruit brunch (EFB), oil palm mass and oil palm stem (OPS) as alternative material for wood-based industry in producing various commercial product have been extensively explored. Nevertheless, the used of OPS as raw material replacing hardwood species in plywood production has been in practice for the past 10years. However, high resin consumption and low mechanical properties in OPS plywood are still the limitation. Hence, in this study we explored the potential of a new resin treatment approach using LmwPF in order to produce high grade OPS plywood. Pilot scale production of LmwPF treated OPS plywood was assessed for properties such as, thickness swelling, water absorption, hot-press pressure, bonding integrity, density, the modulus of rupture (MOR) and modulus of elasticity (MOE). LmwPF resin treatment of OPS in plywood production indicated that with this new resin treatment method, improvement of ⩾200% in strength, ⩾259% in stiffness, dimensional stability (⩾6% thickness swelling and ⩾36% water absorption) as well as, 28% and 80% greater in dry and WBP shear, respectively as compare to the conventional method of commercial OPS plywood.

Properties Enhancement of Oil Palm Plywood through Veneer Pretreatment with Low Molecular Weight Phenol-Formaldehyde Resin

One of the problems dealing with oil palm stem (OPS) plywood is the high veneer surface roughness that results in high resin consumption during the plywood manufacturing. In this study, evaluation was done on the effects of pretreatment of OPS veneers with phenol-formaldehyde resin on the bond integrity and bending strength of OPS plywood. OPS veneers were soaked in low molecular weight phenol-formaldehyde resin (LMW PF) for 20 seconds to obtain certain percentage of resin weight gain. OPS plywoods were produced using two types of lay-ups (100% outer veneer type and 100% inner veneer type) and two urea-formaldehyde (UF) adhesive spread amounts (200 g/m2 and 250 g/m2). The results show that pretreating the veneer with LMW PF could reduce the penetration of the adhesive into the fibres during gluing step. UF adhesive spread amount of 200 g/m2 is sufficient to produce good quality OPS plywood. The technique used in this study was able to enhance the mechanical properties of OPS plywood as well as reduce the amount of resin consumption.

Evaluation on some finishing properties of oil palm plywood

Oil palm is the largest and most important plantation crop in Malaysia. The oil palm generally lasts for 25–30 years before the next replantation is done. Substantial amount of biomass in the form of palm trunk results from plantation cycle. This resource is simply left on the ground to decay and is not used as raw material to manufacture any kind of value-added products. The objective of this study was to investigate the possibility of manufacturing plywood from oil palm trunks and to evaluate some of the finishing properties of such experimental panels in comparison to those from Shorea sp as control samples. Three-ply plywood samples were produced from 5 mm thick veneers of oil palm using urea formaldehyde adhesive. Three types of chemicals, namely nitrocellulose, pre-catalyzed lacquer and polyurethane were used to finish experimental panels. The surface finished with nitrocellulose had the lowest contact angle on raw surface of oil palm plywood and wood. The average cross cut tape index of oil palm plywood was comparable to Shorea sp. All finishing materials of oil palm plywood produced impact rating of 4 except for surface finished with nitrocellulose while finishing on wood indicated an impact rating of 3. Oil palm plywood had higher weight loss compared to Shorea sp. Based on results from contact angle, cross cut tape index, impact rate test, weathering, and soil burial test methods it appears that the samples showed acceptable finishing properties comparable to those of solid wood.