Efficiency of High-Frequency Pressing of Spruce Laminated Timber Bonded with Casein Adhesives

This study identifies the importance of reducing press times by employing high-frequency pressing of spruce-laminated timber bound with sustainable casein adhesives. Spruce lamellas with dimensions of 12 × 10 × 75 cm were bonded into five-layered laminated timber and then separated into single-layer solid wood panels. Three types of casein (acid casein from two sources and rennin) were used. To compare the effectiveness of the casein formulation, two control samples bonded with polyvinyl acetate (PVAc) adhesive were pressed at room temperature (20 °C) and also with high-frequency equipment. The tests included compression shear strength, modulus of rupture, modulus of elasticity and screw withdrawal resistance on the wood panel surface and in the glue line. The average values of casein-bonded samples compression strengths ranged from 1.16 N/mm2 and 2.28 N/mm2, for modulus of rupture (MOR) were measured 85 N/mm2 to 101 N/mm2 and for modulus of elasticity (MOE) 12,200 N/mm2 to 14,300 N/mm2. The screw withdrawal resistance (SWR) on the surface of the wood panels ranged from 91 N/mm to 117 N/mm and in the adhesive line from 91 N/mm to 118 N/mm. Control samples bonded with PVAc adhesive did not perform better for compression shear strength, MOR and MOE, but for SWR in the adhesive line with 114 N/mm. Casein-bonded spruce timber pressed with HF equipment represents a sustainable new product with reduced press times, hazardous emissions and improved workability.

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Influence of Adhesive Systems on the Mechanical and Physical Properties of Flax Fiber Reinforced Beech Plywood

Polymers ◽

10.3390/polym13183086 ◽

2021 ◽

Vol 13 (18) ◽

pp. 3086

Author(s):

Johannes Jorda ◽

Günther Kain ◽

Marius-Catalin Barbu ◽

Alexander Petutschnigg ◽

Pavel Král

Keyword(s):

Shear Strength ◽

Epoxy Resin ◽

Modulus Of Elasticity ◽

Elasticity Modulus ◽

Urea Formaldehyde ◽

Flax Fiber ◽

Modulus Of Rupture ◽

Fiber Reinforced ◽

Adhesive Systems ◽

Screw Withdrawal

In order to improve the acceptance of broader industrial application of flax fiber reinforced beech (Fagus sylvatica L.) plywood, five different industrial applicated adhesive systems were tested. Epoxy resin, urea-formaldehyde, melamine-urea formaldehyde, isocyanate MDI prepolymer, and polyurethane displayed a divergent picture in improving the mechanical properties—modulus of elasticity, modulus of rupture, tensile strength, shear strength and screw withdrawal resistance—of flax fiber-reinforced plywood. Epoxy resin is well suited for flax fiber reinforcement, whereas urea-formaldehyde, melamine urea-formaldehyde, and isocyanate prepolymer improved modulus of elasticity, modulus of rupture, shear strength, and screw withdrawal resistance, but lowered tensile strength. Polyurethane lowered the mechanical properties of flax fiber reinforced plywood. Flax fiber reinforced epoxy resin bonded plywood exceeded glass fiber reinforced plywood in terms of shear strength, modulus of elasticity, and modulus of rupture.

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Influence of Moisture Content in some Mechanical Properties of Two Brazilian Tropical Wood Species

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1025-1026.42 ◽

2014 ◽

Vol 1025-1026 ◽

pp. 42-45 ◽

Cited By ~ 1

Author(s):

Luiz A. Melgaço N. Branco ◽

Eduardo Chahud ◽

André Luis Christoforo ◽

Francisco Antonio Rocco Lahr ◽

Rosane A.G. Battistelle ◽

...

Keyword(s):

Mechanical Properties ◽

Shear Strength ◽

Moisture Content ◽

Analysis Of Variance ◽

Wood Species ◽

Modulus Of Elasticity ◽

Modulus Of Rupture ◽

Tropical Wood ◽

Fiber Saturation ◽

Brazilian Standard

This study aimed, with the aid of analysis of variance (ANOVA), to investigate and quantify the influence of moisture ranging between 12% and over 30% (fiber saturation) on the mechanical properties: strength and modulus of elasticity in compression and in tension parallel to grain; modulus of rupture and modulus of elasticity in static bending; shear strength parallel to grain considering wood species Ipê (Tabebuia sp) and Angelim Araroba (Vataireopsis araroba). Tests were performed according to the assumptions and calculating methods Brazilian standard ABNT NBR 7190, Anexx B, totalizing 400 tests. Results of ANOVA revealed a significant reduction (16% on average) for mechanical properties wood due to the increase in moisture content from 12% to over 30% (fiber saturation). The same behavior also occurred when assembly containing the two species was considered.

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Properties of Particleboard in Correlation with Mat Weight and Press Factor

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d5226.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 6803-6807

Keyword(s):

Mechanical Properties ◽

Modulus Of Elasticity ◽

Control Mechanism ◽

Commercial Production ◽

Raw Material ◽

Modulus Of Rupture ◽

Tropical Species ◽

Internal Bonding ◽

Manufacturing Control ◽

Screw Withdrawal

The influence of resin types on board properties and the correlation to mat weight and press factor on commercial production of particleboard were investigated. These factors could be used as the control mechanism for board making in order to predict final board properties. The resins used in this study were the lower emission resin E0, E1 and EC. Rubberwood and mix tropical species were used as raw material for manufacturing particleboard with thickness of 18mm. This research was done at Mieco Chipboard Bhd. The boards were tested for their mechanical properties which are modulus of rupture (MOR), modulus of elasticity (MOE), internal bonding (IB) and screw withdrawal. Overall, the result shows that board made from E0 resin had better MOE, MOR and IB. Meanwhile the result of screw edge showed that board made from E1 resin is better with the value of 510N. The result also showed high correlation between mat weight and press factor (0.937) and contributed in particleboard manufacturing control

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SIFAT PAPAN PARTIKEL DARI SERAT TANDAN KOSONG SAWIT DAN SERBUK KAYU DENGAN PEREKAT UREA FORMALDEHIDA (The Properties of Particle Board from Oil Palm Empty Fruit Bunches Fiber Sawdust with Urea Formaldehyde Resin)

Jurnal Riset Industri Hasil Hutan ◽

10.24111/jrihh.v8i1.2062 ◽

2016 ◽

Vol 8 (1) ◽

pp. 1

Author(s):

Djoko Purwanto

Keyword(s):

Bond Strength ◽

Modulus Of Elasticity ◽

Internal Bond ◽

Urea Formaldehyde ◽

Internal Bond Strength ◽

Modulus Of Rupture ◽

Particle Board ◽

Palm Fiber ◽

Empty Fruit Bunches ◽

Screw Withdrawal

A palm oil mill with a capacity of hundred thousand tons of fresh fruit bunches per year will produce palm fiber waste about 12,000 tons. Recently, the use of palm empty fruit bunches (OPEFB) fiber is as fuel for electricity generation in the industry. Palm fiber waste contains lignocellulose materials as a feedstock to particle board manufacture. The aim of this research is to evaluate the properties of particle board from a mixture of OPEFB fiber and sawdust. The ratio of OPEFB fiber and sawdust are 100% : 0%; 75% : 25%; 50% : 50%; 25% : 75% and 0% : 100%, plus urea formaldehyde adhesive in a concentration of 11%. The boards were pressed using a clamp pressure of 16 kg/cm2 for 15 minutes at a temperature of 110 – 120 0C. The testing methods and standards of physical properties (moisture contents, thickness swelling, density) and mechanical (modulus of elasticity/MOE, modulus of rupture/MOR, screw withdrawal and internal bond strengths) refers to the SNI. 03 – 2105 - 2006. The results showed that the particle board made from 100% OPEFB fiber produces modulus of elasticity/MOE 1594.88 kg/cm2; modulus of rupture/MOR 18.08 kg/cm2; screw withdrawal 31.34 kg/cm2 and internal bond strength 0.86 kg/cm2. The addition of sawdust for 50% can improve modulus of elasticity/MOE, modulus of rupture/MOR and internal bond strength.

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Sifat Fisis dan Mekanis Papan Semen dari Serat Tandan Kosong Kelapa Sawit (The Physical and Mechanical Properties of Cement Board Made from Oil Palm Empty Fruit Bunches Fibers)

Jurnal Riset Industri Hasil Hutan ◽

10.24111/jrihh.v8i2.1966 ◽

2016 ◽

Vol 8 (2) ◽

pp. 43-52 ◽

Cited By ~ 2

Author(s):

Djoko Purwanto

Keyword(s):

Mechanical Properties ◽

Water Absorption ◽

Oil Palm ◽

Modulus Of Elasticity ◽

Physical And Mechanical Properties ◽

Modulus Of Rupture ◽

Thickness Swelling ◽

Empty Fruit Bunches ◽

Screw Withdrawal ◽

Cement Board

Oil palm empty fruit bunches (OPEFB) fiber were industrial waste that has not been widely used by the community, only stacked and cause odors that interfere with the surrounding environment. This research studied the utilization of OPEFB fiber for cement board products using cement as resin and CaCl2 as accelerator. Laboratory scale cement board made from OPEFB fiber were mixed with cement, and CaCl2. The composition of fiber and cement were 1:1, 1:1.5, 1:2, and CaCl2 variations were 0%, 1% and 3%. A mixture of fibers, cement and CaCl2 was compressed at the pressure of 4 ton for 24 hours. The cement boards were tested for physical and mechanical properties according to JIS A 5417-1992, and the results were compared to the requirements of the cement board JIS A 5417-1992. Cement board made from fiber and cement composition 1:1.5 and CaCl2 content 3% produced moisture content, thickness swelling, water absorption, density, modulus of rupture/MOR, modulus of elasticity/MOE and screw withdrawal strength that met the requirement of JIS A 5417-1992. The composition of fiber and cement and the variations of CaCl2 content produced significant effect on water content, water absorption, thickness swelling, modulus of rupture/MOR, modulus of elasticity/MOE and screw withdrawal strength on cement boards.Keywords : oil palm empty fruit bunches fiber, cement boards, physical and mechanical properties

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Mechanical properties of Ficus vallis-choudae (Delile), a lesser utilized species in Nigeria

BioResources ◽

10.15376/biores.15.3.6550-6560 ◽

2020 ◽

Vol 15 (3) ◽

pp. 6550-6560

Author(s):

Lawrence Aguda ◽

Babatunde Ajayi ◽

Sylvester Areghan ◽

Yetunde Olayiwola ◽

Aina Kehinde ◽

...

Keyword(s):

Mechanical Properties ◽

Shear Strength ◽

Moisture Content ◽

Modulus Of Elasticity ◽

Bending Strength ◽

High Strength ◽

Strength Properties ◽

Modulus Of Rupture ◽

Impact Bending ◽

Timber Market

Declining availability of the prime economic species in the Nigerian timber market has led to the introduction of Lesser-Used Species (LUS) as alternatives. Their acceptability demands information on the technical properties of their wood. The aim of this study was to investigate the mechanical properties of Ficus vallis-choudae to determine its potential for timber. Three mature Ficus vallis-choudae trees were selected and harvested from a free forest area in Ibadan, Oyo State, Nigeria. Samples were collected from the base (10%), middle (50%), and top (90%) along the sampling heights of each tree, which was further partitioned into innerwood, centrewood, and outerwood across the sampling radial position. Investigations were carried out to determine the age, density, moisture content, impact strength, modulus of elasticity, modulus of rupture, compressive strength parallel-to-grain, and shear strength parallel-to-grain. The mean impact bending strength, modulus of rupture, modulus of elasticity, maximum shear strength parallel-to-grain, and maximum compression strength parallel-to-grain for Ficus vallis-choudae at 12% moisture content were 20.4 N/mm2, 85.8 N/mm2, 709 N/mm2, 10.7 N/mm2, and 33.6 N/mm2, respectively. The study found the species to be dense with high strength properties in comparison with well-known timbers used for constructional purposes.

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Effect of Compression Ratio and Lay Angle of Metal Net on the Mechanical Properties of Metal Net-LVL Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.418-420.505 ◽

2011 ◽

Vol 418-420 ◽

pp. 505-508

Author(s):

Jin Li ◽

Ying Cheng Hu

Keyword(s):

Mechanical Properties ◽

Shear Strength ◽

Mechanical Strength ◽

Compression Ratio ◽

Modulus Of Elasticity ◽

Modulus Of Rupture ◽

Horizontal Shear ◽

Fast Growing

In order to improve the mechanical strength of LVL, metal net was inserted into the LVL (metal net-LVL composite) made of fast-growing poplar. In this study, the effects of compression ratio and lay angle of metal net (which is lay angle for short in this paper) on the mechanical properties of the metal net-LVL composite was investigated in a comparative way. In order to find out the optimum compression ratio and lay angle, the modulus of rupture (MOR), modulus of elasticity (MOE) and horizontal shear strength of the metal net-LVL composite were tested. The results showed that the effects of the compression ratio on MOR, MOE and horizontal shear strength were significant, with increasing of compression ratio, the values of MOR and MOE showed an earlier raised and later decreased state, and had the maximum values at 31%. The effects of lay angle on MOR and MOE were significant, the values of MOR and MOE increased first and then decreased with lay angle increasing, and the maximum values were obtained at 20°, though there were no significant effects on horizontal shear strength, there were the maximum values at 20°. Therefore, when the compression ratio was 31% and the lay angle was 20°, the metal net-LVL composite could obtain the optimal overall mechanical properties.

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Variations in Physico-Mechanical Properties of Lonchocarpus sericeus (Poir), a Lesser-Used Species in West Africa

Forest Products Journal ◽

10.13073/fpj-d-21-00004 ◽

2021 ◽

Vol 71 (3) ◽

pp. 252-261

Author(s):

Lawrence Olanipekun Aguda ◽

Babatola Olufemi ◽

Babatunde Ajayi ◽

Olajide Rasaq Adejoba ◽

Adedeji Robert Ojo ◽

...

Keyword(s):

Mechanical Properties ◽

Shear Strength ◽

Modulus Of Elasticity ◽

Bending Strength ◽

High Strength ◽

Modulus Of Rupture ◽

Wood Age ◽

Lonchocarpus Sericeus ◽

The Mean ◽

End Use

Abstract This study investigates the properties of Lonchocarpus sericeus to determine its potential use for timber. Three matured trees of L. sericeus were selected from a forest located in Longe Village, Oluyole Local Government Area in Oyo State, Nigeria. Discs from the harvested trees were collected at the base (10%), middle (50%), and top (90%) and further partitioned into inner wood, center wood, and outer wood. An investigation was carried out to characterize the wood age, density, shrinkage, impact strength, modulus of elasticity, modulus of rupture, compressive, and shear strength. The ages were 28, 29 and 32 years. The mean wood density at 12 percent moisture content was 836.63 kg/m3, which shows that it belongs to the high-density wood category. The mean shrinkage values in the radial, tangential, and longitudinal directions were 2.50, 3.99, and 0.78 percent respectively; the volumetric shrinkage was 6.36 percent. These shrinkage values were indicative of good dimensional stability. The mean impact bending strength, modulus of rupture, modulus of elasticity, maximum shear strength parallel to grain, and maximum compression strength parallel to the grain were 24.14, 114.18, 11,276, 12.76, and 47.16 N/mm2, respectively. End-use assessments suggest that the wood species can be used in similar applications as well-known timbers. The study found L. sericeus to be very dense with high strength in comparison to well-known timbers. It was observed that the mechanical properties of the species decrease from the base to the top and also increase from the outer wood to the core wood.

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Water-Resistant Casein-Based Adhesives for Veneer Bonding in Biodegradable Ski Cores

Polymers ◽

10.3390/polym12081745 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1745 ◽

Cited By ~ 1

Author(s):

Ronald Schwarzenbrunner ◽

Marius Catalin Barbu ◽

Alexander Petutschnigg ◽

Eugenia Mariana Tudor

Keyword(s):

Shear Strength ◽

Physical Properties ◽

Modulus Of Elasticity ◽

Polyvinyl Acetate ◽

Water Storage ◽

Real Life ◽

Modulus Of Rupture ◽

Thickness Swelling ◽

Winter Conditions ◽

Mechanical And Physical Properties

The aim of this study is to investigate the performance of casein-based adhesives for the bonding of ash (Fraxinus spp.) veneers for the manufacture of biodegradable skis. Different formulations containing casein powder, water, lime, sodium silicate, and various glue amounts were tested for shear strength after water storage, modulus of rupture and modulus of elasticity, water absorption, and thickness swelling. Two other classic wood adhesives, namely epoxy and polyvinyl acetate (PVAc) type D4 were used as control. The highest efficiency of both mechanical and physical properties was recorded for the samples glued with caseins and an increased amount of lime. There was also an affinity between casein adhesive distribution and physical and mechanical plywood performance. Moreover, the developed casein-based glues were also used to bond the plywood for ski cores and tested in real-life winter conditions.

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Research on Mechanical Properties of Bambusa Distegia Thread Plywood

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.1394 ◽

2012 ◽

Vol 482-484 ◽

pp. 1394-1397

Author(s):

Yun Shui Yu ◽

Wei Hong Zhou ◽

Xue Liu ◽

Xue Liang Xiong

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Shear Strength ◽

Modulus Of Elasticity ◽

Hot Pressing ◽

Modulus Of Rupture ◽

Pressing Pressure ◽

Horizontal Shear ◽

Concrete Form

Bambusa distegia were used to make bamboo thread plywood by the process of producing thread, dipping thread into glue, assembling pattern and pressing. Influence of hot pressing pressure on mechanical properties of bambusa distegia thread plywood was investigated, which was 2.0MPa，2.5MPa，3.0MPa，3.5MPa and 4.0MPa respectively. The results indicate that the modulus of rupture(MOR), modulus of elasticity(MOE), compressive strength(CS), and horizontal shear strength(HSS) increase with the increasing of hot pressing pressure. Mechanical properties of the Bambusa distegia thread plywood are higher than the indices of plywood for concrete form and the indices of plywood for container flooring.

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