scholarly journals Chipboards as raw material of furniture

2021 ◽  
Vol 875 (1) ◽  
pp. 012041
Author(s):  
E M Razinkov ◽  
M A Savinkov ◽  
Yu A Litvinova
Keyword(s):  
Phenol Formaldehyde ◽  
Urea Formaldehyde ◽  
Gas Bubbles ◽  
Environmentally Friendly ◽  
Raw Material ◽  
Free Form ◽  
Curing Process ◽  
Liquid Resin ◽  
Permissible Level ◽  
Microscopy Method

Abstract The problem of using wood materials in residential premises is closely related to the issues of forestry. This is due to the fact that the wood subsequently processed into materials and products emits a gas harmful to humans - formaldehyde. In Russia, there are strict requirements for the permissible level of formaldehyde in the air (0.01 mg/m3) both in residential premises and in the atmosphere. The environmentally friendly wood emits formaldehyde. The emission of formaldehyde may exceed the permissible level up to 10 times when obtaining chipboards using urea-formaldehyde and phenol-formaldehyde resins. Such an excess of the permissible level of formaldehyde is especially characteristic for chipboards. Moreover, a much larger amount of formaldehyde is emitted from urea-formaldehyde and phenol-formaldehyde resins during their hot curing than it is in the liquid resin in its free form. Therefore, much attention in this work is paid to the curing process of urea-formaldehyde and phenol-formaldehyde resins in relation to the manufacturing conditions of chipboards. The study of this process was based on the models related to the manufacturing conditions of chipboards using the microscopy method. It was found that some formaldehyde is preserved in vapor-gas bubbles and eventually moves out the chipboards.

scholarly journals Bio-Based Alternatives to Phenol and Formaldehyde for the Production of Resins

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2237 ◽  
Author(s):  
P. R. Sarika ◽  
Paul Nancarrow ◽  
Abdulrahman Khansaheb ◽  
Taleb Ibrahim
Keyword(s):  
Raw Materials ◽  
Phenol Formaldehyde ◽  
Raw Material ◽  
Wood Industry ◽  
Suitable Material ◽  
The Past ◽  
Wide Range ◽  
Recent Developments ◽  
Sustainable Materials ◽  
Materials Used

Phenol–formaldehyde (PF) resin continues to dominate the resin industry more than 100 years after its first synthesis. Its versatile properties such as thermal stability, chemical resistance, fire resistance, and dimensional stability make it a suitable material for a wide range of applications. PF resins have been used in the wood industry as adhesives, in paints and coatings, and in the aerospace, construction, and building industries as composites and foams. Currently, petroleum is the key source of raw materials used in manufacturing PF resin. However, increasing environmental pollution and fossil fuel depletion have driven industries to seek sustainable alternatives to petroleum based raw materials. Over the past decade, researchers have replaced phenol and formaldehyde with sustainable materials such as lignin, tannin, cardanol, hydroxymethylfurfural, and glyoxal to produce bio-based PF resin. Several synthesis modifications are currently under investigation towards improving the properties of bio-based phenolic resin. This review discusses recent developments in the synthesis of PF resins, particularly those created from sustainable raw material substitutes, and modifications applied to the synthetic route in order to improve the mechanical properties.

Development and Validation of a Green Analytical Method for the Determination of Norfloxacin in Raw Material by FTIR Spectrophotometry

2016 ◽  
Vol 99 (6) ◽  
pp. 1533-1536 ◽  
Author(s):  
Jéssica Sayuri Hisano Natori ◽  
Eliane Gandolpho Tótoli ◽  
Hérida Regina Nunes Salgado
Keyword(s):  
Urinary Tract ◽  
Organic Solvents ◽  
Analytical Method ◽  
Environmentally Friendly ◽  
Raw Material ◽  
Waste Generation ◽  
Ftir Spectrophotometry ◽  
Tract Infections ◽  
Development And Validation

Abstract Norfloxacin is a broad-spectrum antimicrobial agent, widely used in humans and animals for the treatment of urinary tract infections. It is a second-generation fluoroquinolone. Several analytical methods to analyze norfloxacin have been described in the literature. However, most of them are complex and require the use of large amounts of organic solvents. This paper describes the development and validation of a green analytical method for the determination of norfloxacin in raw material by FTIR spectrophotometry. This method does not require the use of organic solvents, minimizing waste generation in the process and its environmental impacts. The development of methods that promote the reduction, prevention, or elimination of waste generation has become highly attractive to the pharmaceutical industry because of the growing demand from civil society and government authorities for environmentally friendly products and services. The FTIR spectrophotometry method was validated according to International Conference on Harmonization guidelines, showing adequate linearity (r = 0.9936), precision, accuracy, and robustness. This validated method can be used as an environmentally friendly alternative for the quantification of norfloxacin in raw material in QC routine analysis.

Influence of the particle size on the physical, mechanical and tribological properties of composites for brake pads

2021 ◽  
pp. 36-40
Author(s):  
F.F. Yusubov
Keyword(s):  
Particle Size ◽  
Composite Materials ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Phenol Formaldehyde ◽  
Environmentally Friendly ◽  
Brake Pads ◽  
Mechanical And Tribological Properties ◽  
Pin On Disk ◽  
Properties Of Composites

Tribotechnical indicators of environmentally friendly frictional composite materials with phenol-formaldehyde matrix are studied. Friction tests were carried out on a MMW-1 vertical tribometer according to the pin-on-disk scheme. Keywords: brake pads, composites, friction and wear, plasticizers, degradation, porosity. [email protected]

Albizia richardiana King & Prain as a raw material for ply and particleboard

2015 ◽  
Vol 22 (3) ◽  
pp. 139-141
Author(s):  
Md. Rahaman ◽  
Khurshid Akhter ◽  
S. Hossain ◽  
Md. Islam
Keyword(s):  
Bending Strength ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Solid Content ◽  
Raw Material ◽  
Standard Specification ◽  
Press Temperature ◽  
Albizia Richardiana ◽  
German Standard ◽  
Press Time

Woods of Albizia richardiana has been studied for assessing the suitability for plywood and particleboard manufacture. It was found that 1.5 mm thick smooth and figured veneer can be peeled and dried easily. Three-ply plywood were made using veneer of this species bonded with liquid urea formaldehyde glue of 50% solid content extended with wheat flour and catalyzed (ammonium chloride) with 2% hardener under the three specific pressures, viz,1.05 N/mm2, 1.40 N/mm2, 1.76 N/mm2 in three replications at 6 minute press time and 120°C press temperature. Dry and wet shear test were conducted on the sample and their shear load at failure per unit area and percentage of wood failure were determined. 1.05 N/mm2 pressure for the manufacture of plywood was found to be the best. The physical and mechanical properties of Albizia richardiana wood particleboard were studied. The particleboards were tested for determining the strength and dimensional stability. The tensile strength 0.56N/mm2 passed the British and German standard specification, bending strength (modulus of rupture10.80N/mm2) was found nearest to Indian Standard but low German and British standard specification.

Preparation and Application of Modified Soybean Protein Adhesives

2010 ◽  
Vol 139-141 ◽  
pp. 706-709
Author(s):  
Zi Tao Sang ◽  
Shi Feng Zhang ◽  
Qiang Gao ◽  
Jian Zhang Li
Keyword(s):  
Sodium Hydroxide ◽  
Bonding Strength ◽  
Phenol Formaldehyde ◽  
Soybean Protein ◽  
Ftir Spectra ◽  
Absorption Peak ◽  
Type I ◽  
Curing Process ◽  
Protein Adhesives

In this study, a sodium hydroxide modified soybean protein adhesive (NSP adhesive) was prepared and mixed with phenol-formaldehyde (PF) resin in a ratio of 7:3 to form a compound adhesive (NSPF adhesive), and three-layer plywoods were prepared using the NSP adhesive and the NSPF adhesive. In order to understand the reactions between SP and PF resin during the curing process of NSPF adhesive, the SEM and FTIR spectra were employed to character the adhesives and the bonding strength of the plywoods was measured. The results showed that the bonding strength of the poplar plywood prepared with NSPF reached 1.00 MPa, and met type I plywood requirement in GB/T 17657-1999. There was new absorption peak appear at 1390 cm-1 in the FTIR spectra of NSPF adhesive, indicating that there were -NHCH2- structures generate in NSPF during the curing process in this research.

Effect of wood acidity and catalyst on UF resin gel time

Holzforschung ◽  
2004 ◽  
Vol 58 (4) ◽  
pp. 408-412 ◽  
Author(s):  
C. Xing ◽  
S.Y. Zhang ◽  
J. Deng
Keyword(s):  
Ph Value ◽  
Raw Materials ◽  
Urea Formaldehyde ◽  
Acid Catalyst ◽  
Buffering Capacity ◽  
Raw Material ◽  
Gel Time ◽  
Uf Resin ◽  
Effects Of Ph ◽  
Fiber Materials

Abstract Knowledge of pH and buffering capacity of raw fiber materials is important for understanding the effects of raw material on the curing rate of urea formaldehyde (UF) resin, used for panel manufacturing, especially with some less-desirable wood materials such as bark, top, and commercial thinnings. The effects of pH and buffering capacity as well as catalyst content on the gel time of UF resin were investigated. The results obtained from this study indicate that bark has a lower pH value as well as higher acid and alkaline buffering capacities than wood of the same species due to their extractives. The pH values of the raw fiber materials studied decrease with increased absolute and relative acid buffering capacity due to the increased absolute acidity mass in the solution. At lower levels of added catalyst, the effect of raw material pH on UF resin gel time is significant, while it is insignificant at higher catalyst contents. This may be due to the acidity of wood, which is the main acid catalyst source of the mixture at lower levels of added catalyst, while at higher levels, catalyst is the main source. With higher catalyst contents, all studied raw materials mixed with UF resin result in a longer gel time than does UF resin alone.

scholarly journals Formulation Development and Performance Characterization of Ecological Dust Suppressant for Road Surfaces in Cities

2021 ◽  
Vol 11 (21) ◽  
pp. 10466
Author(s):  
Yuan Wang ◽  
Cuifeng Du ◽  
Mengmeng Cui
Keyword(s):  
Moisture Absorption ◽  
Environmentally Friendly ◽  
Road Dust ◽  
Raw Material ◽  
Retention Performance ◽  
Formulation Development ◽  
Performance Characterization ◽  
Material Sources ◽  
Road Surfaces

In order to solve the problem of road dust pollution, an ecological dust suppressant for road surfaces has been developed using monomer, orthogonal, and optimization experiments and based on the dust raising mechanism. A humectant, hygroscopic agent, coagulant and surfactant and their concentration ranges have been determined through monomer experiment. The preliminary formula of the dust suppressant has been obtained through orthogonal experiment, with the water loss rate, moisture content rate, viscosity value, and surface tension value serving as experimental indexes. The optimal formula for the dust suppressor has been calculated through an optimization experiment, with the toxicity, moisture absorption and retention performance of plants, and the relative damage rate of plant seeds serving as experimental indexes. Based on the performance characterization of ecological road dust suppressant, the ecologically and environmentally friendly dust suppressant demonstrates fine moisture absorption and retention performance, good wind and rain erosion resistance, and no toxicity. The ecological road dust suppressant developed herein covers extensive raw material sources. It is ecologically and environmentally friendly, fit for most urban roads, and has a fine dust suppression effect. Meanwhile, it also can bring in good economic and social benefits, demonstrating its broad application prospects.

scholarly journals Particleboards from Recycled Thermally Modified Wood

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1462
Author(s):  
Ján Iždinský ◽  
Zuzana Vidholdová ◽  
Ladislav Reinprecht
Keyword(s):  
Mechanical Properties ◽  
Urea Formaldehyde ◽  
Brown Rot ◽  
Decay Resistance ◽  
Raw Material ◽  
Modulus Of Rupture ◽  
Negative Effect ◽  
Serpula Lacrymans ◽  
Thermally Modified Wood ◽  
Modified Wood

In recent years, the production and consumption of thermally modified wood (TMW) has been increasing. Offcuts and other waste generated during TMWs processing into products, as well as already disposed products based on TMWs can be an input recycled raw material for production of particleboards (PBs). In a laboratory, 16 mm thick 3-layer PBs bonded with urea-formaldehyde (UF) resin were produced at 5.8 MPa, 240 °C and 8 s pressing factor. In PBs, the particles from fresh spruce wood and mixed particles from offcuts of pine, beech, and ash TMWs were combined in weight ratios of 100:0, 80:20, 50:50 and 0:100. Thickness swelling (TS) and water absorption (WA) of PBs decreased with increased portion of TMW particles, i.e., TS after 24 h maximally about 72.3% and WA after 24 h maximally about 64%. However, mechanical properties of PBs worsened proportionally with a higher content of recycled TMW—apparently, the modulus of rupture (MOR) up to 55.5% and internal bond (IB) up to 46.2%, while negative effect of TMW particles on the modulus of elasticity (MOE) was milder. Decay resistance of PBs to the brown-rot fungus Serpula lacrymans (Schumacher ex Fries) S.F.Gray increased if they contained TMW particles, maximally about 45%, while the mould resistance of PBs containing TMW particles improved only in the first days of test. In summary, the recycled TMW particles can improve the decay and water resistance of PBs exposed to higher humidity environment. However, worsening of their mechanical properties could appear, as well.

scholarly journals Lignosulphonates as an Alternative to Non-Renewable Binders in Wood-Based Materials

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4196
Author(s):  
Sofia Gonçalves ◽  
João Ferra ◽  
Nádia Paiva ◽  
Jorge Martins ◽  
Luísa H. Carvalho ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Aromatic Ring ◽  
Phenol Formaldehyde ◽  
Urea Formaldehyde ◽  
Value Added ◽  
Wood Adhesives ◽  
Renewable Source ◽  
Pressing Time ◽  
Value Added Products ◽  
Total Market

Lignin is a widely abundant renewable source of phenolic compounds. Despite the growing interest on using it as a substitute for its petroleum-based counterparts, only 1 to 2% of the global lignin production is used for obtaining value-added products. Lignosulphonates (LS), derived from the sulphite pulping process, account for 90% of the total market of commercial lignin. The most successful industrial attempts to use lignin for wood adhesives are based on using this polymer as a partial substitute in phenol-formaldehyde or urea-formaldehyde resins. Alternatively, formaldehyde-free adhesives with lignin and lignosulphonates have also been developed with promising results. However, the low number of reactive sites available in lignin’s aromatic ring and high polydispersity have hindered its application in resin synthesis. Currently, finding suitable crosslinkers for LS and decreasing the long pressing time associated with lignin adhesives remains a challenge. Thus, several methods have been proposed to improve the reactivity of lignin molecules. In this paper, techniques to extract, characterize, as well as improve the reactivity of LS are addressed. The most recent advances in the application of LS in wood adhesives, with and without combination with formaldehyde, are also reviewed.

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