scholarly journals Properties of Plywood Produced with Urea-Formaldehyde Adhesive Modified with Nanocellulose and Microcellulose

2020 ◽  
Vol 71 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Jakub Kawalerczyk ◽  
Dorota Dziurka ◽  
Radosław Mirski ◽  
Kinga Szentner
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Urea Formaldehyde ◽  
Rheological Behaviour ◽  
Formaldehyde Emission ◽  
Solid Content ◽  
Curing Process ◽  
Gel Time ◽  
Bonding Quality ◽  
Adhesive Mixtures

Urea-formaldehyde adhesives are widely used in the wood-based materials industry. The study investigates the possibility of using cellulosic particles as a filler that modifies the properties of the resin and consequently improves the properties of plywood. Moreover, the study also examines the differences between microcellulose and nanocellulose used as a filler for UF adhesive. Based on the investigations, it was found that the addition of MFC and NCC significantly affected the curing process and rheological behaviour of adhesive mixtures. Modification led to increase of viscosity and extension of a gel time caused by lowering solid content of the resin. The experimental and reference plywood were tested in terms of bonding quality and mechanical properties such as modulus of elasticity and modulus of rigidity in accordance with applicable standards. The results of the tests confirmed that both the amount and the type of modifier added to the resin had a significant effect on the properties of plywood. The bonding quality and the above mentioned mechanical properties improved in all variants of modification; however the most effective was the addition of NCC in the amount of 10 %/100 g of solid resin. The slight decrease of formaldehyde emission was only observed for 5 % cellulosic particles added to 100 g of solid UF.

scholarly journals Hemp flour as a formaldehyde scavenger for melamine-urea-formaldehyde adhesive in plywood production

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 4052-4064
Author(s):  
Jakub Kawalerczyk ◽  
Joanna Siuda ◽  
Radosław Mirski ◽  
Dorota Dziurka
Keyword(s):  
Mechanical Properties ◽  
Urea Formaldehyde ◽  
Formaldehyde Emission ◽  
Solid Content ◽  
Filling Material ◽  
Bonding Quality ◽  
Rye Flour ◽  
Adhesive Mixtures ◽  
Reference Mixture

The possibility of using hemp flour as a filling material for melamine-urea-formaldehyde (MUF) adhesive was investigated for the process of manufacturing plywood. Adhesive mixtures were filled with various amounts of hemp flour and compared to rye flour as a reference mixture, and their properties were tested. The quantity of added filler had a significant effect on the resins viscosity. Moreover, the replacement of rye flour with the hemp flour resulted in acceleration of gel time and a slight increase in solid content. Due to the high proteins content, hemp flour led to a significant reduction of formaldehyde emission. Bonding quality of plywood made with hemp flour as a filling material for the adhesive mixture meet the requirements from the standard. Introducing it in an amount of 20 pbw and 25 pbw (parts by weight) allowed for the production of plywood characterized by equally good mechanical properties as that of reference plywood glued with an adhesive mixed with rye flour. In summary, the proper amounts of hemp flour can be applied as a filling material and formaldehyde scavenger for MUF adhesive without the deterioration of mechanical properties of manufactured plywood.

scholarly journals THE SOY FLOUR AS AN EXTENDER FOR UF AND MUF ADHESIVES IN BIRCH PLYWOOD PRODUCTION

Wood Research ◽  
2021 ◽  
Vol 66 (6) ◽  
pp. 1015-1031
Author(s):  
JAKUB KAWALERCZYK ◽  
JOANNA SIUDA ◽  
DOROTA DZIURKA ◽  
RADOSŁAW MIRSKI ◽  
MAGDALENA WOŹNIAK ◽  
...  
Keyword(s):  
Chemical Interaction ◽  
Urea Formaldehyde ◽  
Formaldehyde Emission ◽  
Solid Content ◽  
Urea Formaldehyde Resin ◽  
Soy Flour ◽  
Formaldehyde Resin ◽  
Gel Time ◽  
Major Disadvantage ◽  
Muf Adhesives

Formaldehyde emission still remains a major disadvantage of widely applied formaldehyde-containing amino resins such as UF (urea-formaldehyde) resin and MUF (melamine-urea-formaldehyde) resin. The compositions of adhesives for plywood manufacturing have to contain a proper extenders in order to adjust their viscosity. Thus, the aim of the study was to investigate the effect of protein-rich soy flour (SF) as the extender for adhesives. The composition of flours and their ability to absorb the formaldehyde were determined. Properties of liquid resins such as gel time, viscosity, pH and solid content were investigated. The possible chemical interaction between the extenders and resins were assessed with the use of FTIR spectroscopy. Plywood panels manufactured using UF and MUF adhesives with the soy flour introduced as the extender in various concentrations were tested in terms of shear strength and formaldehyde release. Studies have shown that soy flour has a favorable composition and formaldehyde-scavenging ability. The addition of SF affected resins properties such as viscosity and gel time but showed no influence on their pH and solid content. FTIR analysis has not explained the chemical interaction between resin and extender. The application of soy flour in the concentration of 15% for UF resin and 10% for MUF resin allowed to produce plywood characterized by improved bonding quality and decreased formaldehyde emission.

scholarly journals The Application of Oak Bark Powder as a Filler for Melamine-Urea-Formaldehyde Adhesive in Plywood Manufacturing

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1249 ◽  
Author(s):  
Radosław Mirski ◽  
Jakub Kawalerczyk ◽  
Dorota Dziurka ◽  
Joanna Siuda ◽  
Marek Wieruszewski
Keyword(s):  
Fourier Transform ◽  
Chemical Composition ◽  
Wood Species ◽  
Chemical Interaction ◽  
Urea Formaldehyde ◽  
Solid Content ◽  
Formaldehyde Resin ◽  
Gel Time ◽  
Bonding Quality ◽  
Formaldehyde Release

The woodworking industry generates a great amount of bark which has not yet found a wider industrial application. None of the previously conducted research has considered oak bark application (which is one of the most often processed wood species in Poland) as a filler for wood adhesives. Moreover, no studies have determined the properties of bark containing melamine-urea-formaldehyde resin (MUF), which increasingly replaces pure urea-formaldehyde adhesives. Thus, the aim of the study was to determine the possibility of grinded oak bark application as a filler for MUF adhesive in plywood manufacturing. The chemical composition of oak bark was evaluated. Properties of liquid resins, such as viscosity, gel time, pH, and solid content, were determined. Chemical interaction between the filler and resin was assessed with using Fourier-transform infrared (FTIR) spectroscopy. Plywood panels manufactured using MUF adhesive filled with different bark concentrations (10%, 15%, 20%, 25%) were tested in terms of such properties as formaldehyde release and bonding quality. Studies have shown an improvement in liquid resin properties. The course of FTIR spectra did not explain the chemical interaction between the polymer and the filler. The addition of oak bark at a concentration of 15% made it possible to produce plywood panels characterized by reduced formaldehyde release and improved bonding quality.

scholarly journals Possibility of Use of NCC-Reinforced Melamine-Urea- Formaldehyde Adhesive in Plywood Manufacturing

2021 ◽  
Vol 72 (3) ◽  
pp. 279-289
Author(s):  
Jakub Kawalerczyk ◽  
Dorota Dziurka ◽  
Radosław Mirski ◽  
Joanna Siuda ◽  
Marta Babicka
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Modulus Of Elasticity ◽  
Bending Strength ◽  
Urea Formaldehyde ◽  
Fourier Transform Infrared ◽  
Bonding Quality ◽  
Adhesive Mixtures

The possibility of using nanocellulose (NCC) as a filling substance for melamine-urea-formaldehyde (MUF) adhesive was investigated for the process of manufacturing plywood. The adhesive mixtures were prepared with various nanocellulose concentrations. The amount of introduced filler had a significant effect on both resin and plywood characteristics. Fourier transform infrared spectroscopy (FTIR) did not show any major changes between experimental and reference variants. The viscosity of resin increased after the introduction of nanocellulose. The addition of NCC in the amount of 5 g and 10 g per 100 g of solid resin led to an improvement in bonding quality, modulus of elasticity and bending strength. Further increase of NCC concentration caused a deterioration of manufactured plywood properties. In summary, the addition of proper amount of nanocellulose resulted in manufacturing plywood with improved properties.

scholarly journals Effect of Veneer-Drying Temperature on Selected Properties and Formaldehyde Emission of Birch Plywood

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 593 ◽  
Author(s):  
Pavlo Bekhta ◽  
Ján Sedliačik ◽  
Nataliya Bekhta
Keyword(s):  
Modulus Of Elasticity ◽  
Bonding Strength ◽  
Elevated Temperatures ◽  
Bending Strength ◽  
Phenol Formaldehyde ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Formaldehyde Emission ◽  
Bonding Quality ◽  
Mean Values

In this study, the effect of the veneer-drying process at elevated temperatures on selected properties and formaldehyde emission of plywood panels was determined. We assume that during the veneer drying at high temperatures, more formaldehyde is released from it, and therefore, a lower formaldehyde emission can be expected from the finished plywood. Prior to bonding, birch veneers were dried at 160 °C (control) and 185 °C in an industrial veneer steam dryer (SD) and at 180 °C, 240 °C and 280 °C in an industrial veneer gas dryer (GD). Two types of adhesives were used: urea–formaldehyde (UF) and phenol–formaldehyde (PF) resins. Bonding quality, bending strength and modulus of elasticity in bending, water absorption and thickness swelling of plywood samples were determined. The formaldehyde emission level of samples was also measured. It was concluded from the study that the effects of veneer-drying temperatures on the bonding strength and physical and mechanical properties of plywood panels were significant. Veneer-drying temperatures of 185 °C/SD, 180 °C/GD and 240 °C/GD negatively affected the bending strength and the modulus of elasticity along and across the fibres for both UF and PF plywood samples. Bonding strength mean values obtained from all test panels were above the required value (1.0 MPa) indicated in EN 314-2 standard. The lowest formaldehyde emissions for the UF and PF plywood samples were observed in the samples from veneer dried in a steam dryer at 185 °C/SD.

scholarly journals Mechanical Properties of Commercial Particleboard from Rubberwood (Hevea Brasiliensis) and Recycle Mix-Tropical Wood with Different Board Density

2021 ◽  
Vol 3 (1) ◽  
pp. 41-44
Author(s):  
Nur Wafa Amalina Amali ◽  
Nor Yuziah Mohd Yunus ◽  
Wan Mohd Nazri Wan Abdul Rahman
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Hevea Brasiliensis ◽  
Urea Formaldehyde ◽  
Wood Particle ◽  
Modulus Of Rupture ◽  
Internal Bonding ◽  
Board Density ◽  
Tropical Wood ◽  
Minimum Requirements

In this study, mechanical properties of commercially manufactured hybrid particleboard from mix-tropical wood and rubberwood with four different densities at 25mm thickness have been investigated. The particleboard sample cutting and testing was in accordance to EN312:2013. The density of particleboard is identified with interval of 10kg/m3 for different densities which include 660kg/m3, 670kg/m3, 680kg/m3 and 690kg/m3. Particleboards were made with the ratio of 40:60 for mix-tropical wood particle and rubberwood particle respectively. The particleboards were prepared with urea formaldehyde (UF) with E1 formulation with addition of wax and hardener.  Increment of 10kg/m3 density for each particleboard led to increase in internal bonding (IB), bending testing include modulus of rupture (MOR) and modulus of elasticity (MOE), surface soundness (SS) and screw edge (SE) withdrawal. It was found that with board increment of 10kg/m3, the improvement was not statically significant except that for MOR. All panels met the minimum requirements of standard.

scholarly journals KUALITAS PAPAN PARTIKEL BERDASARKAN KOMPOSISI SEKAM PADI DAN KAYU SENGON DENGAN VARIASI KADAR PEREKAT

2019 ◽  
Vol 7 (2) ◽  
Author(s):  
Dendi Prayoga ◽  
. Dirhamsyah ◽  
. Nurhaida
Keyword(s):  
Mechanical Properties ◽  
Moisture Content ◽  
Rice Husk ◽  
Raw Materials ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Solid Content ◽  
Particle Board ◽  
Rice Husks ◽  
Wood Processing

This research aimed to examine the physical and mechanical properties of particle boards based on the composition of raw materials and adhesive content and know the treatment of the composition of raw materials and the best adhesive content and meet the standard JIS A 5908-2003. The research was conducted at Wood Workshop Laboratory, Wood Processing Laboratory Faculty of Forestry,Tanjungpura University and Laboratory of PT. Duta Pertiwi Nusantara Pontianak. The adhesive used is Urea Formaldehyde with 52% Solid Content. Comparison of the composition of rice husks and sengon varies namely rice husk 50%: sengon 50%, rice husk 60%: sengon 40% and rice husk 70%: sengon 30%  and variations in the levels of UF adhesives, namely 14% and 16%, with target density 0,7 gr/cm3. The particleboard was 30 cm x 30 cm x 1 cm Pressing at temperature 140oC for 8 minutes, with  pressure of 25 kg/cm2. The research results of the study of density and moisture content meet the standards JIS A 5908-2003. The best particle values of rice husk and sengon  with composition a ratio of  rice husk 50%: sengon 50% , 16% adhesive content  16%, with density value of  0,7072 gr/cm3, moisture content 9,1949 %, thick development 12,3210 %, water absorption 68,8270 %, MOE 12110,7273 kg/cm2, MOR 161,0025 kg/cm2, firmness sticky 1,9320 kg/cm2, screw holding strength 62,3124 kg.Keywords : adhesive, composition, particle board, rice husk, sengon

The effect of phenol-formaldehyde adhesive modification with fire retardant on the properties of birch plywood

2019 ◽  
Vol 106 ◽  
pp. 197-113
Author(s):  
JAKUB KAWALERCZYK ◽  
DOROTA DZIURKA ◽  
RADOSŁAW MIRSKI ◽  
ADRIAN TROCIŃSKI ◽  
MAREK WIERUSZEWSKI
Keyword(s):  
Weight Loss ◽  
Shear Strength ◽  
Phenol Formaldehyde ◽  
Fire Retardant ◽  
Solid Content ◽  
Burned Area ◽  
Gel Time ◽  
Bonding Quality ◽  
Resin Mixture ◽  
Gelling Time

The effect of phenol-formaldehyde adhesive modification with fire retardant on the properties of birch plywood. The study investigated how the modification of phenol-formaldehyde adhesive with a mixture of potassium carbonate and urea affect the properties of plywood. Based on the investigations of the viscosity, gel time and solid content of PF resin mixture containing various amounts of modifiers with various compositions it was found that modification led to major decrease in viscosity, caused the elongation of gelling time and reduced the solid content. In all variants modification of the resin led to significant improvement in plywood flammability evaluated on the basis of parameters such as: weight loss, time of ignition and burned area. The addition of fire retardant to the resin caused a decrease of shear strength. Composition of the modifier had a significant effect on bonding quality, however all plywood samples retained good values exceeding 1 N/mm2 required by EN 314-2 (1993).

scholarly journals Properties of Particleboard from Sawmill Wastes and Rubberwood (Hevea brasiliensis) with Different Board Thickness and Resin Content

2019 ◽  
Vol 8 (4) ◽  
pp. 6808-6812
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Hevea Brasiliensis ◽  
Urea Formaldehyde ◽  
Resin Content ◽  
Modulus Of Rupture ◽  
Internal Bonding ◽  
Thickness Swelling ◽  
Board Thickness ◽  
European Standards

This study investigate the effect of the board thickness and resin content on the properties of particleboard. Single-layered sawmill wastes and rubberwood particleboards bonded with urea formaldehyde (UF) resins were manufactured. The boards were fabricated with three different board thicknesses (15, 18 and 25mm) at three different resin contents (7, 8 and 9%). The boards produced were evaluated for their modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) and thickness swelling (TS) in accordance with the European Standards. Board thickness does affect the mechanical properties of particleboard. The study revealed that thinner boards gave higher MOE, MOR, IB and TS. No significant effects were found among three resin contents for MOE, MOR, IB and TS. It can be concluded that the particleboard made from mix tropical wood from sawmill waste and with rubberwood were suitable for particleboard manufacturing.

Effect of Melamine Content in MUF Resin on the Durable Properties of Plywood

2011 ◽  
Vol 71-78 ◽  
pp. 3160-3164 ◽  
Author(s):  
Xiao Ying Liu ◽  
Ji Zhi Zhang ◽  
Yong Lin Yang ◽  
Shi Feng Zhang ◽  
Jian Zhang Li
Keyword(s):  
Mechanical Properties ◽  
Ammonium Chloride ◽  
Urea Formaldehyde ◽  
Accelerated Aging ◽  
Formaldehyde Emission ◽  
Acidic Condition ◽  
Uf Resin ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Modified Urea

The effect of melamine content in melamine modified urea formaldehyde (MUF) resin on durable properties of plywood was investigated using ammonium chloride (NH4Cl) with different melamine/urea (M/U) ratios. The plywood specimens were exposed to laboratory accelerated aging and/or cyclic soak-dry (SD). The experiment results indicated that the melamine contents in MUF resin showed an unobservable effect on the durable properties of MUF resin bonded plywood. The mechanical properties of plywood decreased more severely after accelerated aging test in acidic condition. However, the influence of different curing catalyst contents on mechanical properties and formaldehyde emission of UF resin can be minimized by adding melamine to the resin.

Sign in / Sign up

Export Citation Format

Share Document