scholarly journals The study of powdered phenol-formaldehyde resins for the manufacture of plywood

2020 ◽  
Author(s):  
Г.С. Варанкина ◽  
Д.С. Русаков ◽  
Е.Г. Соколова ◽  
А.Н. Чубинский
Keyword(s):  
Composite Materials ◽  
Phenol Formaldehyde ◽  
Phenol Formaldehyde Resin ◽  
Bonding Time ◽  
Formaldehyde Resin ◽  
Free Phenol ◽  
Adhesive Composition ◽  
Main Components ◽  
Bonding Method ◽  
Branched Chains

В настоящее время перед отечественным производителем древесных композиционных материалов стоят задачи по увеличению объемов производства, повышению качества и конкурентоспособности, снижению токсичности выпускаемой продукции. Решение этих задач основано на разработке новых и совершенствовании имеющихся технологий современного производства клеёв и композиционных материалов на их основе. Цель исследования – повышение эффективности производства фанеры путём применения клеев на основе порошкообразных термореактивных полимеров поликонденсационного типа. Для достижения поставленной цели в работе необходимо исследовать влияние наполнителя на свойства клеевой композиции и готовой продукции. Исходными компонентами для проведения экспериментов являлись порошковая фенолоформальдегидная смола и аэросил технический. Установлено, что введение аэросила технического в клеящие составы на основе поликонденсационной порошковой фенолоформальдегидной смолы СФЖ-3013 увеличивает прочность фанеры, также с увеличением количества наполнителя уменьшается содержание свободных продуктов в смоле: содержание свободных фенола и формальдегида уменьшается до 0,05 – 0,06% и 0,02 – 0,03% соответственно. Предполагается, что при горячем способе склеивания происходит гелеобразование, частицы аэросила образуют разветвленные цепочки ~Si-O-Si~, которые целиком пронизывают объем клея, этот процесс сопровождается связыванием формальдегида в процессе структурирования. Полученные результаты исследований могут быть использованы в работе специалистов деревообрабатывающих производств при управлении технологическими процессами склеивания. Разработанные составы клеевой композиции на основе фенолоформальдегидных смол, модифицированных (наполненных) техническим аэросилом позволяют сократить расход клеевых материалов; повысить прочность и качество склеиваемой продукции; ускорить процесс отверждения связующего; сократить продолжительность склеивания; снизить энергозатраты путем уменьшения времени склеивания; уменьшить себестоимость клея, за счёт замещения основных компонентов наполнителем. At present, the domestic manufacturer of wood composite materials is faced with tasks to increase production volumes, improve quality and competitiveness, and reduce the toxicity of manufactured products. The solution to these problems is based on the development of new and improvement of existing technologies for the modern production of adhesives and composite materials based on them. The purpose of the study is to increase the efficiency of plywood production by using adhesives based on powdered thermoset polymers of the polycondensation type. To achieve this goal in the work, it is necessary to study the effect of the filler on the properties of the adhesive composition and finished products. The initial components for the experiments were powder phenol-formaldehyde resin and technical aerosil. It was found that the introduction of technical aerosil in adhesives based on polycondensation powder phenol-formaldehyde resin SFZh-3013 increases the strength of plywood, as the amount of filler increases, the content of free products in the resin decreases: the content of free phenol and formaldehyde decreases to 0.05 – 0.06% and 0.02 – 0.03%, respectively. It is assumed that during the hot bonding method, gel formation occurs, so that aerosil particles form branched chains ~ Si-O-Si ~ that completely penetrate the glue volume, this process is accompanied by formaldehyde bonding during structuring. The obtained research results can be used in the work of specialists in woodworking industries in the management of gluing processes. The developed compositions of the adhesive composition based on phenol-formaldehyde resins modified (filled) with technical aerosil allow you to: reduce the consumption of adhesive materials; to increase the strength and quality of glued products; speed up the curing process of the binder; shorten bonding time; reduce energy costs by reducing the bonding time; reduce the cost of glue, due to the replacement of the main components with filler.

Borax Modify Phenol-Formaldehyde Resin as Wood Adhesives

2012 ◽  
Vol 610-613 ◽  
pp. 507-513 ◽  
Author(s):  
Rui Hang Lin ◽  
Xiao Feng Zhu ◽  
Xiao Bo Wang ◽  
Zhen Zhong Gao
Keyword(s):  
Phenol Formaldehyde ◽  
Thermodynamic Characteristics ◽  
Phenol Formaldehyde Resin ◽  
Curing Temperature ◽  
Alkaline Condition ◽  
Formaldehyde Resin ◽  
Scanning Calorimetry ◽  
Free Phenol ◽  
Thermo Gravimetric Analyzer ◽  
Infrared Spectrometer

A modified phenol-formaldehyde (PF) resin was synthesized under alkaline condition in varying proportion of borax up to 21% (w/w). All the prepared resin were characterized by free phenol content, free formaldehyde content as well as hydroxymethyl content. It was proved by Fourier transform infrared spectrometer (FTIR) that B-O bond had been successfully introduced into the structure of PF resin. Thermo gravimetric analyzer (TGA) and different scanning calorimetry (DSC) were used to characterize the thermodynamic characteristics of the PF resin. The result showed that when the mass fraction of borax was 9wt.% of PF resin, the heat resistance was the best and the curing temperature of the modified PF resin was higher than that of the unmodified PF resin.

scholarly journals Preparation of low-toxicity cast foamed phenolic plastics

Vestnik MGSU ◽  
2019 ◽  
pp. 1132-1139
Author(s):  
Nguyen Viet Cong ◽  
Nikolay Y. Sosnovskiy ◽  
Valentin P. Yanchuk ◽  
Anastasia M. Smirnova ◽  
Larisa S. Grigorieva
Keyword(s):  
Ferric Chloride ◽  
Phenol Formaldehyde ◽  
Volume Ratio ◽  
Phenol Formaldehyde Resin ◽  
Complexing Agent ◽  
Formaldehyde Resin ◽  
Filled Polymers ◽  
Chromatography Method ◽  
Mass Unit ◽  
Free Phenol

Introduction. Gas-filled polymers are highly efficient building thermal insulation materials, and therefore, researching to develop technologies to create them is a promising task. Phenol-formaldehyde foamed plastic can be a high-potential material with many significant advantages. However, the high toxicity of the phenol and formaldehyde compounds it releases is a significant deterrent to its usage. Therefore, the purpose of this study was to search for ways to reduce the toxicity of foamed plastic. The research considered the method of using ferric chloride as a complexing agent that binds phenol, with simultaneous use of sodium hexafluorosilicate to reduce material consumption. Materials and methods. The studies were carried out on phenol-formaldehyde resin FRV-1A (TU 6-05-1104-78 “Resin, phenol-formaldehyde, foaming, brand FRV-1A”) and curing agent VAG-3 (TU 6-55-1116-88 “Product VAG-3”). The number of free phenol monomers was determined through gas chromatography method following GOST 11235-2017 “Phenoloformaldehyde resins. Methods for determination of free phenol”. The tests were carried out using a Tsvet-4 chromatograph. Tests on determining the foaming rate were carried out according to TU 6-05-1104-78 “Resin, phenol-formaldehyde, foaming, brand FRV-1A”. The density of the samples was measured basing on the mass-to-volume ratio of the samples. Strength was determined using samples of size 50 × 50 × 50 mm mm at 10 % compression on a test press. Results. The conducted studies showed a decrease in the content of free phenol monomers in samples modified with ferric chloride. The use of sodium hexafluorosilicate allows significantly reducing the density of the finished material and, consequently, reducing the toxicity of foamed phenolic plastic per material mass unit. Conclusions. According to the obtained results, the most effective for detoxifying a cast foamed phenolic plastic is the use of ferric chloride in an amount of 2 % of the FRV-1A oligomer mass with the addition of 0.5 % of the sodium hexafluorosilicate mass. The use of this method for modifying phenol-formaldehyde resin foam in the future may make it possible to obtain a much safer material and expand its areas of application.

scholarly journals Mechanical properties (Tensile, Hardness and Shock resistance) for the phenol formaldehyde resin with Epoxy resin

2019 ◽  
Vol 12 (2) ◽  
pp. 35-43
Author(s):  
Mustafa A. Rajab
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Composite Materials ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Phenol Formaldehyde ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Shock Resistance

Phenolic formaldehyde (resole) resin was used at a different weight (10%, 20%, 30%, 40%), with epoxy resins at varying percentages (90%, 80%, 70%, 60%) at 20 C °. In order to study the mechanical properties (which including: Tensile strength, hardness and shock resistance), for the purpose of analysis and comparison with the mechanical properties of alloys, and the selected part for the purpose of replacing the alloy with the composite materials to reduce weight and improve mechanical properties. The results indicate improved properties with increased epoxy resins due to increased bonding between components.

scholarly journals THE RESEARCH OF CONDITIONS FOR THE FORMATION OF PHENOL FORMALDEHYDE RESINS MODIFIED WITH HYDROXYL CONTAING POLYETHER POLYOL

2020 ◽  
pp. 52-56
Keyword(s):  
Maleic Anhydride ◽  
Phenol Formaldehyde ◽  
Molar Fraction ◽  
Reaction Medium ◽  
Phenol Formaldehyde Resin ◽  
Chain Extender ◽  
Formaldehyde Resin ◽  
Free Phenol ◽  
A Chain ◽  
Polyether Polyol

The aim of the study was to study the conditions of copolycondensation of phenol alcohol with hydroxyl-containing polyether polyol in the presence of maleic anhydride chain extender in order to obtain modified thermoset phenolic-formaldehyde oligomers. Investigation of the dependence of the content of free phenol, formaldehyde and methylol groups on time during the synthesis of the modified phenol-formaldehyde resin with the ratios hydroxyl-containing polyether polyol:phenol alcohol 1:60 mol/mol and 1:100 mol/mol. It was revealed that maleic anhydride, present in the reaction medium as a copolycondensation catalyst, also participates in copolycondensation reactions as a chain extender. Moreover, as the molar fraction of phenol alcohol increases in the synthesis, an increase in the amount of maleic anhydride involved as a chain extender and an increase in the molecular weight of the resulting modified phenol-formaldehyde oligomer are observed.

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.

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