Acoustical properties of wood fiberboards prepared with different densities and resin contents

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 5291-5304
Author(s):  
Se-Hwi Park ◽  
Min Lee ◽  
Pureun-Narae Seo ◽  
Eun-Chang Kang ◽  
Chun-Won Kang
Keyword(s):  
Sound Absorption ◽  
Bending Strength ◽  
Pinus Densiflora ◽  
Urea Formaldehyde ◽  
Wood Fiber ◽  
Main Property ◽  
Morphological Properties ◽  
Formaldehyde Resin ◽  
Wood Fibers ◽  
Reducing Ability

The demand for noise control in residential environments is steadily increasing, but the currently available noise-reducing materials used in walls and floors are unsustainable and expensive. As an alternative, wood-fiber could be a good resource to manufacture eco-friendly acoustic materials. In this study, fiberboards were prepared by mixing wood-fibers (Pinus densiflora) with melamine-urea-formaldehyde resin adhesive, obtaining specimens with different final densities and resin contents. The acoustic, physical, and morphological properties of the fiberboards were investigated. The sound absorption was greatly influenced by the density of the fiberboard: lower densities showed higher sound absorption performances. Furthermore, the low-frequency absorption coefficient was higher for lower resin contents. The materials met all the criteria required by the Korean standards for fiberboards. As the density increased, the dimensional stability and the bending strength increased; in contrast, the physical properties were not affected by the resin content. Microscopy observations confirmed that specimens with different densities and resin contents had different porosities; the porosity was assumed to be the main property that governs the noise-reducing ability. Due to their eco-friendliness and inexpensiveness, these fiberboards offer themselves as efficient and effective alternative sound-absorbing materials.

The Research on Wood Fiber/Stainless Steel Net Electromagnetic Shielding Composite Board

2012 ◽  
Vol 525-526 ◽  
pp. 437-440
Author(s):  
Chu Wang Su ◽  
Quan Ping Yuan ◽  
Wei Xing Gan ◽  
Jing Da Huang ◽  
Yuan Yi Huang
Keyword(s):  
Stainless Steel ◽  
Bending Strength ◽  
Urea Formaldehyde ◽  
Wood Fiber ◽  
Electromagnetic Shielding ◽  
Formaldehyde Resin ◽  
Shielding Effectiveness ◽  
Composite Board ◽  
The One ◽  
Internal Bonding Strength

In this paper, the electromagnetic shielding function composite fiberboards were made by filling with stainless steel nets dipped with urea-formaldehyde resin adhesive (UF) and the influence of different mesh and layers of nets on its electromagnetic shielding performance, static bending strength (MOR), modulus of elasticity (MOE) and internal bonding strength (IB) were studied. The results showed that: when the mechanical strength was enough and the frequency was in range of 50MHz to 1GHz, of all the composite fiberboards filled with one-layer stainless steel net, the one filled with 60 mesh was best and the minimum shielding effectiveness (SE) was 36.22 dB; when filled with two-layers nets, the one filled with 80 mesh was best and the minimum SE was 42.54dB; when filled with three-layers nets, the one filled with 60 mesh was best and the minimum SE was 50.77dB.

scholarly journals Properties of High-Density Fiberboard Bonded with Urea–Formaldehyde Resin and Ammonium Lignosulfonate as a Bio-Based Additive

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2775 ◽  
Author(s):  
Petar Antov ◽  
Viktor Savov ◽  
Neno Trichkov ◽  
Ľuboš Krišťák ◽  
Roman Réh ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Urea Formaldehyde ◽  
Thermal Analyses ◽  
Formaldehyde Emission ◽  
High Density ◽  
Formaldehyde Resin ◽  
Gravimetric Analysis ◽  
Wood Fibers ◽  
Uf Resin

The potential of ammonium lignosulfonate (ALS) as an eco-friendly additive to urea–formaldehyde (UF) resin for manufacturing high-density fiberboard (HDF) panels with acceptable properties and low free formaldehyde emission was investigated in this work. The HDF panels were manufactured in the laboratory with very low UF resin content (4%) and ALS addition levels varying from 4% to 8% based on the mass of the dry wood fibers. The press factor applied was 15 s·mm−1. The physical properties (water absorption and thickness swelling), mechanical properties (bending strength, modulus of elasticity, and internal bond strength), and free formaldehyde emission were evaluated in accordance with the European standards. In general, the developed HDF panels exhibited acceptable physical and mechanical properties, fulfilling the standard requirements for HDF panels for use in load-bearing applications. Markedly, the laboratory-produced panels had low free formaldehyde emission ranging from 2.0 to 1.4 mg/100 g, thus fulfilling the requirements of the E0 and super E0 emission grades and confirming the positive effect of ALS as a formaldehyde scavenger. The thermal analyses performed, i.e., differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and derivative thermogravimetry (DTG), also confirmed the main findings of the research. It was concluded that ALS as a bio-based, formaldehyde-free adhesive can be efficiently utilized as an eco-friendly additive to UF adhesive formulations for manufacturing wood-based panels under industrial conditions.

scholarly journals SHORT NOTES: APPLICATION OF MINERAL FILLER IN MEDIUM DENSITY FIBERBOARD (MDF) AND ITS EFFECT ON MATERIAL PROPERTIES AS A FUNCTION OF PARTICLE SIZE

Wood Research ◽  
2021 ◽  
Vol 66 (5) ◽  
pp. 891-899
Author(s):  
TOMASZ OZYHAR
Keyword(s):  
Particle Size ◽  
Material Properties ◽  
Filler Content ◽  
Urea Formaldehyde ◽  
Medium Density Fiberboard ◽  
Strength Properties ◽  
Inorganic Filler ◽  
Formaldehyde Resin ◽  
Medium Density ◽  
Wood Fibers

The addition of inorganic filler material in medium density fiberboard (MDF) and the effect on material properties as a function of particle size was examined. Medium density fiberboard was manufactured in a laboratory scale environment to a target raw densityof 750 kgm-3. Wood fibers were replaced by using calcium carbonate at 3 and 10 wt.% using fillers with weighted median particle sizes of d50= 2.0 μm and d50= 30 μm, respectively. Urea formaldehyde resin was used as binder in all MDF. The influence of filler addition on the modulus of elasticity, bending and tensile strength, dimensional stability and liquid permeability was investigated. The results demonstrate the effect of filler content and its dependence on particle size. The addition of filler with d50= 30 μm does not have any influence on material properties up to a filler content of 10 wt.%. Using the finer filler with d50= 2.0 μm at 10 wt.% filler, the quantity significantly increases the water adsorption and swelling behavior and reduces the strength properties of the MDF.

Sound Absorption Coefficients Natural Fibre Reinforced Composites

2013 ◽  
Vol 701 ◽  
pp. 53-58 ◽  
Author(s):  
Elammaran Jayamani ◽  
Sinin Hamdan
Keyword(s):  
Sound Absorption ◽  
Urea Formaldehyde ◽  
Weight Fraction ◽  
Natural Fibre ◽  
Solid Content ◽  
Formaldehyde Resin ◽  
Hot Press ◽  
Absorption Coefficients ◽  
Kenaf Core ◽  
Core Fibre

In this Investigation, the influence of two kind of polymers (Urea-formaldehyde and Polypropylene) mixed with natural fibre (Kenaf) were studied for their sound absorption coefficients. Four samples were made; Samples A1 and A2 are made of Kenaf core fibre with adhesive of high emission Urea-formaldehyde resin (HN 100) with 51.6 % solid content. The fabrication of the particle board was done using a hot press for 6 minutes under the pressure of 40 Ton at 180°C for different fibre lengths 1 mm (Sample A1) and 0.6 mm (Sample A2) with weight fraction of 80%. Sample B1 and B2 are made of Kenaf core fibre with polypropylene matrix materials with coupling agent of polyvinyl alcohol. The fabrication of the sample was done using hot press for 30 minutes under the pressure of 1000 Psi at 180°C for different lengths of 1 mm (Sample B1) and 0.6 mm (Sample B2) with weight fraction of 20%. The sound absorption coefficients of samples were measured according to American society for Testing Materials (ASTM E1050 10) two microphone method. It is evident that type of polymer influences the sound absorption coefficients.

STUDY OF THE INFLUENCE OF STABILIZERS ON THE PROPERTIES OF CARBAMIDE FOR-MALDEHYDE BINDER AND FC PLYWOOD

2020 ◽  
Vol 10 (1) ◽  
pp. 136-143
Author(s):  
A. Fedotov ◽  
Tat'yana Vahnina ◽  
Andrey Titunin ◽  
Aleksandr Sviridov
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Strength Reduction ◽  
Cohesive Strength ◽  
Urea Formaldehyde Resin ◽  
Strength Characteristics ◽  
Formaldehyde Resin ◽  
Glycerol Mono

The problem of stabilizing the properties of the urea-formaldehyde binder during storage is relevant for both glued products and resins. Changing the performance of the resin during storage makes it difficult to apply a binder and leads to a deterioration in the physical and mechanical properties of plywood. The effect of glycerol, mono- and triethanolamine, as well as a mixture of glycerol and monoethanolamine on the nominal viscosity of the resin after 56 days of storage, has been studied. The use of glycerol and monoethanolamine (including in the complex) reduces the nominal viscosity of the resin by 13.5-24.8%. The use of triethanolamine as a stabilizer makes it possible to reduce the nominal viscosity by 35% in comparison with the index of an unstabilized oligomer. Mechanical properties of FC plywood based on the stabilized and unstabilized binder has been studied. It was found that glycerol additive (or glycerol in combination with monoethanolamine) significantly reduces strength characteristics of plywood, which makes it irrational to use these stabilizers. The addition of 0.2% triethanolamine to CFS allows a 35% reduction in the nominal viscosity of the resin, while the cohesive strength of the binder decreases by 1.5%. The result is within the framework of the dispersion of the indicator, i.e. strength reduction is negligible. The static bending strength of plywood with a stabilized triethanolamine binder is more important than that of control specimens without the addition of stabilizers. The results of the study enable to recommend the addition of triethanolamine in an amount of 0.2% by weight of urea-formaldehyde resin as a rational stabilizer

scholarly journals Effects of the thickness of rotary-cut veneers on properties of plywood sheets. Part 2. Physical and mechanical properties of plywood materials

2012 ◽  
Vol 52 (No. 3) ◽  
pp. 118-129
Author(s):  
J. Hrázský ◽  
P. Král
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Bending Strength ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Institutional Research ◽  
Nominal Thickness

The second part of the paper summarizes results of an institutional research aimed at the determination of physical and mechanical properties of different sets of plywood sheets pressed under different conditions. The first part dealt with the determination of compressibility or values of decreasing the thickness of pressed plywood sheets. In this second part, results are summarized of the analysis of physical and mechanical properties of the set of whole-beech plywood sheets of the nominal thickness of veneers amounting to 1.5 mm. The plywood sheets were manufactured as seven-ply and urea-formaldehyde resin DUKOL S was used for their production. The sheets were pressed using a pressure of 1.5 and 1.7 MPa. Following parameters were analyzed: moisture, density, bending strength, MOE in bending and shear strength.

scholarly journals Lightweight Insulation Boards Based on Lignocellulosic Particles Glued with Agents of Natural Origin

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3219
Author(s):  
Radosław Mirski ◽  
Dorota Dziurka ◽  
Adam Derkowski
Keyword(s):  
Potato Starch ◽  
Urea Formaldehyde ◽  
Wood Fiber ◽  
Acoustic Properties ◽  
Formaldehyde Resin ◽  
Control Board ◽  
Natural Origin ◽  
Food Components ◽  
Binding Agents ◽  
Synthetic Agents

In this study, the possibility of using adhesives of natural origin for the manufacture of wood fiber-based lightweight panels was investigated. The boards, of a density ranging from 150 to 250 kg/m3, were glued together using commercial urea–formaldehyde resin (control board), solutions of rye flour and potato starch and two types of starch: oxidized and gelatinized. The density and density profile, compressive strength, modulus of elasticity, acoustic properties and thermal conductivity were determined in the produced boards. These studies show that when food components are used as binding agents in the manufacture of lightweight wood fiberboards, the properties obtained can be comparable with those of commercial boards manufactured using synthetic agents.

Processing of Fireproof and High Temperature Durable Particleboard from Rice Husk

2015 ◽  
Vol 34 (6) ◽  
Author(s):  
Metin Gürü ◽  
Ahmet F. Karabulut ◽  
Mustafa Yasir Aydın ◽  
İbrahim Bilici
Keyword(s):  
Rice Husk ◽  
Bending Strength ◽  
Oxygen Index ◽  
Urea Formaldehyde ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Limited Oxygen Index ◽  
Three Point Bending ◽  
Fire Point ◽  
Limited Oxygen

AbstractThe aim of this study is the recovery of rice husk waste by researching usability in industry as an alternative to wood. In this study urea formaldehyde resin was used mainly as binding agent for wood-panel used in industry. For the preparation of composite material, ground powder rice husks were mixed with urea formaldehyde resin used in different proportions (65/50, 75/50, 80/50, 85/50, 95/50 by mass of filler/binder). Each particleboard produced in 393.15 K and 9.8 MPa pressure was tested by means of three point bending strength, shore hardness and limited oxygen index (LOI) tests. Particleboard made with 75/50 paddy husk/urea formaldehyde composition material formed of 11.40 MPa specimens showed the highest strength. Limited oxygen index value increased by increasing the filler material usage. The highest LOI value was recorded as 40%. Besides, fire point of particleboards which have the best three point bending strength has been analyzed at environmental atmosphere and 493.15 K has been measured as fire point. The results of the tests showed that this material maybe used instead of wooden plate. The usage of agricultural wastes like these in processing of particleboard will give economically benefits and slow down waste products.

Sign in / Sign up

Export Citation Format

Share Document