Polyamide-formaldehyde resin as a low-toxic adhesive for wood bonding

2021 ◽  
pp. 1-14
Author(s):  
Mengdie Su ◽  
Jinfu Wu ◽  
Peidi Pan ◽  
Haijun Wang
Keyword(s):  
Formaldehyde Resin ◽  
Wood Bonding ◽  
Low Toxic

Study on Synthetic Process of Low Toxic Urea-Formaldehyde Resin

2012 ◽  
Vol 621 ◽  
pp. 79-82
Author(s):  
Gui Hua Chen ◽  
Jian Han ◽  
Xiao Huan Zhang
Keyword(s):  
Bonding Strength ◽  
Ph Value ◽  
Urea Formaldehyde ◽  
Formaldehyde Emission ◽  
Urea Formaldehyde Resin ◽  
Experimental Results ◽  
Formaldehyde Resin ◽  
Synthetic Process ◽  
Resin Adhesive ◽  
Low Toxic

This study aimed at exploring a producing method of urea-formaldehyde resin that contained low free formaldehyde. Effects of the pH value of addition stage, the pH value and the temperature of polycondensation stage on the properties of the resin were analyzed. The experimental results showed that controlling the pH value of addition stage to 7.5-8.0, regulating the pH value of polycondensation stage to 4.8-5.1, and keeping the temperature of polycondensation stage to 88-92°C, a low toxic urea-formaldehyde resin adhesive was obtained which contained free formaldehyde 0.08%. Using this resin adhesive, the bonding strength of the plywood reached 1.7MPa, formaldehyde emission of the plywood was 0.7mg/l, reaching the grade E1.

scholarly journals Features of the Use of Low-Toxic Resins in the Technology of Wood Particle Boards

2017 ◽  
Vol 7 (3) ◽  
pp. 176-182
Author(s):  
Егор Разиньков ◽  
Egor Razinkov
Keyword(s):  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Wood Particle ◽  
Synthesis Process ◽  
Formaldehyde Resin ◽  
Starting Mixture ◽  
Positive Side ◽  
Good Adhesive ◽  
Low Toxic ◽  
And Performance

Source of release of harmful gas of wood particle board (WPB) – formaldehyde is not only free formaldehyde presenting in the formaldehyde resin, but formaldehyde, which is formed from hydroxymethylene groups in a weakly acidic environment during curing the resin during hot pressing of boards. In this, dimethylaniline connections are formed. They are unstable and go into methylene linkages (bridges) with the release of formaldehyde. Currently, with the goal of reducing the discharge formaldehyde from the boards of, low-molal urea-formaldehyde resin is used, mole ratio in which (carbamide (C) : formaldehyde (F) in resins preparing is at the level of (1:1.2 – 1:1.35). Thus we obtain resin with low content of free formaldehyde (0.10-0.15 % by weight of liquid resin). However, it is known that to obtain resins with good adhesive ability, and thus obtaining boards with good physical and mechanical and performance properties, excess of formaldehyde is necessary in its reaction with carbamide. With a relatively small excess of formaldehyde in the starting mixture of urea-formaldehyde we get resins with low reactivity. With increasing quantities of formaldehyde, it is growing vigorously. The highest reactivity corresponds to the mole ratio of carbamide and formaldehyde (C:F) 1:2. When the mole ratio of C:F=1:1 in the synthesis process substances are formed which have no adhesion to the wood. Therefore, the use of low molal resin in wood particleboard technology has not only its positive side (reduced evolution of formaldehyde from plates) but also negative ones (deteriorating physical and mechanical properties of the plates). In this regard for obtaining low-toxic wood particleboard, except for use of low-toxic resins in the technology, it is necessary to apply effective acceptor of formaldehyde. Moreover, it is advisable to use acceptor complex action, which not only linked formaldehyde in the boards, but also improves physical and mechanical and special properties of boards (bio-, water-, atmospheric constancy, etc.).

scholarly journals Ammonia-free, Low-toxic Press-materials with Improved Electroinsulating Properties Based on Modified Novolak Phenol-formaldehyde Resin

2012 ◽  
Vol 6 (2) ◽  
pp. 199-202 ◽  
Author(s):  
Oleh Suberlyak ◽  
◽  
Volodymyr Krasinskiy ◽  
Janusz Sikora ◽  
Aneta Krzyżak ◽  
...  
Keyword(s):  
Phenol Formaldehyde ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Low Toxic

scholarly journals EFFECT OF WOOD GRADING ON THE MECHANICAL PROPERTIES OF GLULAM MADE OF Tectona grandis

FLORESTA ◽  
2014 ◽  
Vol 44 (3) ◽  
pp. 465 ◽  
Author(s):  
Setsuo Iwakiri ◽  
Jorge Luis Monteiro Matos ◽  
José Guilherme Prata ◽  
Rosilani Trianoski ◽  
Carlos Frederico Alice Parchen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Phenol Formaldehyde ◽  
Tectona Grandis ◽  
Axial Direction ◽  
Phenol Formaldehyde Resin ◽  
Stress Waves ◽  
Formaldehyde Resin ◽  
Pressing Time ◽  
Wood Bonding ◽  
Double Surface

AbstractThis study aimed to evaluate the influence of the wood grading by the method of stress waves in the mechanical properties of glued laminated beams (glulam) made of Tectona grandis. A total of 87 battens with dimensions of 25 x 75 x 3.000 mm were obtained from the 5 trees and 3 logs per tree, in the axial direction (base, middle and top) and radial (pith - bark). After drying, the battens were planed to the final dimensions of 20 x 60 x 2200 mm, and then subjected to grading by application of stress waves. Were defined three classes of dynamic modulus of elasticity (DMOE) and the beams were composed with five pre-classified battens. The beams were bonded with resorcinol-phenol-formaldehyde resin, with a weight of 350 g / m² (double surface), specific pressure of 1.0 MPa and pressing time of 8 hours. The grading process of the battens using the stress wave method showed to be efficient for the composition of beams. The results of static bend and glue line shear strength tests indicated the technical feasibility of using wood of Tectona grandis for the production of glued laminated beams.Keywords: Wood bonding; structural wood; resorcinol-phenol-formaldehyde resin. ResumoInfluência da classificação das lamelas nas propriedades mecânicas de vigas laminadas coladas de Tectona grandis. Este trabalho teve como objetivo avaliar a influência da classificação da madeira pelo método de ondas de tensão nas propriedades mecânicas de vigas laminadas coladas de Tectona grandis. Um total de 87 lamelas com dimensões de 25 x 75 x 3.000 mm foram obtidas a partir da amostragem de 5 árvores e 3 toras / árvore, nas direções axial (base, meio e topo) e radial (medula – casca). Após a secagem, as lamelas foram aplainadas para as dimensões finais de 20 x 60 x 2.200 mm, sendo a seguir submetidas à classificação por meio de aplicação de ondas de tensão. Foram estabelecidas três classes de módulo de elasticidade dinâmico (MOEd) e as vigas foram compostas de cinco lamelas pré-classificadas. As vigas foram coladas com resina resorcina-fenol-formaldeído, com gramatura de 350 g/m² (linha dupla), pressão específica de 1,0 MPa e tempo de prensagem de 8 horas. A classificação das lamelas pelo método de ondas de tensão mostrou ser eficiente para a composição das vigas. Os resultados de ensaios de flexão estática e cisalhamento da linha de cola indicaram a viabilidade técnica de uso da madeira de Tectona grandis para produção de vigas laminadas coladas.Palavras-chave: Colagem de madeiras; estruturas de madeira; resina resorcina-fenol-formaldeído.

The Effect of the pH Value of Wood on the Curing Reaction of Low Toxic Urea-Formaldehyde Resin

2010 ◽  
Vol 150-151 ◽  
pp. 1263-1266
Author(s):  
Li Bin Zhu ◽  
Ji You Gu ◽  
Yan Hua Zhang ◽  
Jun Shen
Keyword(s):  
Ph Value ◽  
Wood Flour ◽  
Urea Formaldehyde ◽  
Onset Temperature ◽  
Peak Temperature ◽  
Formaldehyde Resin ◽  
Scanning Calorimetry ◽  
Curing Reaction ◽  
Uf Resin ◽  
Low Toxic

The differential scanning calorimetry(DSC) was used to study the curing reaction of low toxic UF resin with poplar, birch, larch powder in different pH value. The results showed that the effect of different wood flour and its pH value on the curing reaction of UF resin was not the same. Along with the increase of the pH, the peak temperature and the onset temperature was raised; the peak temperature and the onset temperature of poplar was higher than that of the birch. The tempera- ture of the curing reaction of UF resin modified by melamine was higher than the UF resin without modification.

scholarly journals Features of the veneering of panel board details fayn-layn interline interval

2015 ◽  
Vol 5 (4) ◽  
pp. 138-144
Author(s):  
Кантиева ◽  
Ekaterina Kantieva ◽  
Пономаренко ◽  
Larisa Ponomarenko
Keyword(s):  
Growth Rates ◽  
Urea Formaldehyde ◽  
Front Surface ◽  
Average Density ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Working Solution ◽  
Similar Materials ◽  
Low Toxic

Growth rates of production of furniture in our country increase every year. And as the statistics, generally due to production of furniture from slabby glued materials, such as a chipboard, fiber board of average density, plywood shows. Apply to an upclassing of a surface of boards of slabby materials most often PVC films, the decorative paper and layered plastic and much less often the planed interline interval and an interline interval began to use a fayn-line. It is connected by that at a veneering a planed interline interval one of defects of a veneering – infiltration of glue on a front surface of a board very often comes to light. Ways of elimination of such defects aren´t present and therefore the spent materials simply are utilized and hit the pocket the producer. To avoid these risks the producer simply refuses use of similar materials. Our research was reduced increasing viscosity of glue and by that to exclude possibility of its infiltration on a front surface. For this purpose we suggest to enter into working solution gluing a filler – grinding dust. Use of grinding dust in the form of a filler at a veneering of boards allows to solve at once some problems: to use at a veneering of boards low-toxic urea-formaldehyde resin (today in production of products from wood generally urea-formaldehyde resin with a carbamide ratio to formaldehyde 1:1.5 are used), to increase durability of pasting of a basis and facing materials, to reduce marriage percent due to infiltration of glue on a front surface. Results of researches showed that it is possible to use low-toxic urea-formaldehyde resin where the filler in the form of grinding dust will be added to a compounding of glues at a veneering of boards. Optimum values of quantity of a filler from the square of infiltration of glue at a front surface and durabilities of gluing of facing layers to a basis were established.

A Resorcinol-Formaldehyde Resin as an Embedding Material for Electron Microscopy of Membranes

1969 ◽  
Vol 27 ◽  
pp. 328-329 ◽  
Author(s):  
J. G. Robertson ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Neutral Lipids ◽  
Lipid Extraction ◽  
Water Soluble ◽  
Formaldehyde Resin ◽  
Electron Microscope Autoradiography ◽  
Resorcinol Formaldehyde ◽  
Major Disadvantage ◽  
Cell Organization

The extraction of lipids from tissues during fixation and embedding for electron microscopy is widely recognized as a source of possible artifact, especially at the membrane level of cell organization. Lipid extraction is also a major disadvantage in electron microscope autoradiography of radioactive lipids, as in studies of the uptake of radioactive fatty acids by intestinal slices. Retention of lipids by fixation with osmium tetroxide is generally limited to glycolipids, phospholipids and highly unsaturated neutral lipids. Saturated neutral lipids and sterols tend to be easily extracted by organic dehydrating reagents prior to embedding. Retention of the more saturated lipids in embedded tissue might be achieved by developing new cross-linking reagents, by the use of highly water soluble embedding materials or by working at very low temperatures.

Purification of water contaminated with heavy metals by example of lead as promising material based on graphene nanostructures

2020 ◽  
pp. 34-43
Author(s):  
N. R. Memetov ◽  
◽  
A. V. Gerasimova ◽  
A. E. Kucherova ◽  
◽  
...  
Keyword(s):  
Adsorption Process ◽  
Phenol Formaldehyde ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Parameter Estimates ◽  
Maximum Adsorption Capacity ◽  
Ecological Situation ◽  
Characteristic Parameters ◽  
Purification Of Water ◽  
Graphene Nanostructures

The paper evaluates the effectiveness of the use of graphene nanostructures in the purification of lead (II) ions to improve the ecological situation of water bodies. The mechanisms and characteristic parameters of the adsorption process were analyzed using empirical models of isotherms at temperatures of 298, 303, 313 and 323 K, which correspond to the following order (based on the correlation coefficient): Langmuir (0.99) > Temkin (0.97) > Dubinin – Radushkevich (0.90). The maximum adsorption capacity of the material corresponds to the range from 230 to 260 mg/g. We research the equilibrium at the level of thermodynamic parameter estimates, which indicates the spontaneity of the process, the endothermic nature and structure change of graphene modified with phenol-formaldehyde resin during the adsorption of lead (II) ions, leading to an increase in the disorder of the system.

Experimental evaluation of toxicity and neuroparalitical actions of fire-resistant turbine oil «Turbomas»

2020 ◽  
pp. 684-684
Author(s):  
L. V. Lukovnikova ◽  
G. I. Sidorin
Keyword(s):  
Experimental Evaluation ◽  
Intact Skin ◽  
Toxic Compound ◽  
Turbine Oil ◽  
Mucous Membranes ◽  
Low Toxic

The article presents the results of a study of the toxicity of fire-resistant turbine oil «Turbomas «, a derivative of diphenyl-(n-tert-butylphenyl phosphate). According to toxicity parameters, «Turbomas» oil is characterized as a low-toxic compound, does not have neuroparalytic action, exhibits mild cumulative properties, does not irritate the skin and mucous membranes, penetrates intact skin,

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