scholarly journals Improvement of operational properties and technology of plywood of increased water resistance, manufactured with the use of melaminecarbamideformaldehyde resins

2017 ◽  
Author(s):  
Е.Г. Соколова
Keyword(s):  
Bonding Strength ◽  
Water Resistance ◽  
Modern World ◽  
Formaldehyde Resin ◽  
Technological Parameters ◽  
Promising Direction ◽  
Research Results ◽  
Adhesive Composition ◽  
Synthetic Resins

В настоящее время к производству плитной продукции и фанеры предъявлены ужесточенные требования, которые регулируются законодательством. Одной из проблем фанерного производства является уменьшение токсичности фанеры повышенной водостойкости до уровня, определяемого современными мировыми требованиями. Снижение содержания свободного формальдегида в фанере можно достичь с помощью применения специализированных связующих, модифицированных меламином. Использование меламина признано перспективным направлением развития современного фанерного производства. Изложены результаты исследования меламинокарбамидноформальдегидных смол с со- держанием меламина от 20 до 25%, а также результаты исследования влияния содержания меламина в меламинокарбамидноформальдегидной смоле на проч- ность и токсичность фанеры, изготовленной с применением этих смол. Даль- нейшие исследования направлены на совершенствование эксплуатационных свойств (прочность склеивания и токсичность продукции) и технологии фанеры повышенной водостойкости с применением МКФС с содержанием меламина 20%. Одним из эффективных способов повышения прочности клеевого соедине- ния и снижения токсичности фанеры является применение аэросила технического в качестве модификатора для синтетических смол. Разработан рациональный состав клея на основе меламинокарбамидоформальдегидной смолы для склеива- ния шпона. Приведены технологические параметры склеивания фанеры, изго- товленной с применением меламинокарбамидноформальдегидных смол, показатели ее прочности и токсичности. Currently, tightened requirements to production of particleboard and plywood products are presented which are regulated by law. One of the problems in plywood production is the reduction of the toxicity of plywood increased water resistance to the level determined by the modern world requirements. The decrease in the content of free formaldehyde in the plywood can be achieved through the use of special binders modified with melamine. The use of melamine is recognized as a promising direction of development of modern plywood production. The research results of melamine-carbamide-formaldehyde resins containing melamine from 20 to 25% and also results of research of influence of melamine in the melamine-carbamide-formaldehyde resin strength and current-sicnosti plywood, manufactured using these resins. Further research aimed at improving the operational properties (bonding strength and toxicity of products) and technologies of plywood increased water resistance with the use of MKFS resins containing 20% of melamine. One effective way of increasing the bonding strength and reduce the toxicity of the plywood is the use of Aerosil technical as a modifier for synthetic resins. Developed rational adhesive composition based on melamineformaldehyde resin for bonding veneers. The technological parameters of the bonding of plywood, manufactured melamine-carbamide-formaldehyde resins, indicators of its strength and toxicity.

Manufacture of thin rice straw particleboards bonded with various polymeric methane diphenyl diisocyanate/ urea formaldehyde resin mixtures

BioResources ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 935-944
Author(s):  
Peng Luo ◽  
Chuanmin Yang ◽  
Mengyao Li ◽  
Yueqi Wang
Keyword(s):  
Mechanical Properties ◽  
Rice Straw ◽  
Water Resistance ◽  
Urea Formaldehyde ◽  
Single Layer ◽  
Formaldehyde Resin ◽  
Manufacturing Cost ◽  
Board Density ◽  
Layer Medium ◽  
Resin Formulation

Reducing particleboard thickness is one of the major approaches to decrease consumption volume of particleboard for furniture manufacture. This study employed an adhesive mixture of polymeric methane diphenyl diisocyanate (PMDI) and urea formaldehyde (UF) to produce single-layer medium density thin rice straw particleboard. The effects of various PMDI/UF formulations as well as board density on mechanical properties and water resistance of rice straw particleboard were studied. The results indicated that the mechanical properties and water resistance of the thin rice straw particleboard were appreciably affected by resin formulation. The panels bonded with PMDI/UF adhesive mixtures had mechanical properties and water resistance far superior to those bonded with UF. Higher PMDI content levels in resin mixtures led to improved mechanical properties and water resistance. Density influenced mechanical properties and water resistance of the thin rice straw particleboard. Increasing the density of the panel could upgrade the mechanical properties of the thin rice straw particleboard. The experimental outcomes showed that PMDI/UF resin systems had potential to substitute for pure PMDI resin in producing thin rice straw particleboard, which could effectively lower manufacturing cost and bring economic efficiencies due to reduced amount of pricey PMDI.

Preparation and Characterization of Silicate Wood Adhesive Modified with Ammonium Stearate

2014 ◽  
Vol 1033-1034 ◽  
pp. 1048-1053 ◽  
Author(s):  
Xin Li Zhang ◽  
Hong Hui Zhang ◽  
Yi Qiang Wu ◽  
Yun Chu Hu
Keyword(s):  
Bonding Strength ◽  
Water Resistance ◽  
Wood Adhesive ◽  
National Standard ◽  
Adhesion Properties ◽  
Good Thermal Stability ◽  
Thermo Gravimetric Analyzer ◽  
Infrared Spectrometer ◽  
Grade Ii

In order to improve the water resistance of silicate wood adhesive, a kind of silicate adhesive was prepared from water glass with silica as curing agent, and ammonium stearate as modifier. The chemical structure, surface morphology and thermal properties of the silicate adhesive were characterized by Fourier transform infrared spectrometer, scanning electron microscope, and thermo-gravimetric analyzer. As the two main measures of adhesion properties, the bonding strength and water resistance were also determined. The results showed that ammonium stearate was successfully introduced into the molecule structure of silicate, the silicate adhesive have good thermal stability in the range of 30~800 °C and the modified silicate adhesive had more smooth cured morphology. The bonding strength and 24h water absorption rate of poplar plywood glued by the silicate adhesive was 0.71 MPa and 22.81%, respectively, reaching the grade II of plywood performance's national standard.

scholarly journals Effect of carbon nanotubes on the properties of pmb and asphalt concrete

Vestnik MGSU ◽  
2015 ◽  
pp. 110-119 ◽  
Author(s):  
Svetlana Yur’evna Shekhovtsova ◽  
Marina Alekseevna Vysotskaya
Keyword(s):  
Asphalt Concrete ◽  
Water Resistance ◽  
Materials Science ◽  
Crosslinking Agent ◽  
Modern World ◽  
Progressive Development ◽  
Concrete Mixtures ◽  
Deformation Properties ◽  
Strength And Deformation ◽  
Modified Binder

In the modern world nanotechnologies are an integral part of successful and progressive development of all the areas of activity. Materials science is not an exception. The authors studied the method of nanomodification and its influence on the performance properties of polymer-modified binder (PMB) and asphalt concrete, produced on their basis. It is established that nanomodified PMB are less susceptible to aging, which is a consequence of the processes of peptization of asphalt-resin complexes (ARC) in the structure of the modified binder and the crosslinking with the polymer matrix. It is revealed that nanotubes (SWCN or MWCN) used as a modifier, act as crosslinking agent and the inhibitor of the aging process in a PMB. The influence of nanomodified PMB on strength and deformation properties of asphalt concrete is investigated. It was found out that the use of modified binder in the asphalt concrete mixtures enhances the water resistance of asphalt concrete, heat resistance and shear-resistance.

scholarly journals Allyl glycidyl ether-modified animal glue binder for improved water resistance and bonding strength in sand casting

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Chen-chen Fan ◽  
Qian Tang
Keyword(s):  
Tensile Strength ◽  
Bonding Strength ◽  
Room Temperature ◽  
Water Resistance ◽  
Glycidyl Ether ◽  
Animal Glue ◽  
Practical Application ◽  
Foundry Industry ◽  
Dog Bone ◽  
Allyl Glycidyl Ether

This paper aims to develop a modified animal glue sand binder for foundry casting with improved water resistance and bonding strength. An efficient method is reported by using sodium hydroxide as the catalyst to improve the operability of animal glue binder and allyl glycidyl ether as the modifier to improve the water resistance and bonding strength. Sand specimens prepared using allyl glycidyl ether-modified animal glue binder were cured by compressed air at room temperature. The proposed method saves energy and is environmentally friendly and inexpensive. Compared with unmodified animal glue binder, standard dog bone sand specimens with allyl glycidyl ether-modified animal glue binder had higher tensile strength of 2.58 MPa, flowability of 1.95 g, better water resistance (a lower decrease in tensile strength at 25 °C and relative humidity of 60%), and good collapsibility. This allyl glycidyl ether-modified animal glue binder is suitable for practical application in the foundry industry.

Necessity in development of sheet rolling theory, taking into account nonstationarity of technology and negative dynamic effects

2021 ◽  
pp. 510-513
Author(s):  
A.V. Kozhevnikov ◽  
I.A. Kozhevnikova ◽  
V.S. Yusupov
Keyword(s):  
Dynamic Effects ◽  
Technological Parameters ◽  
Sheet Rolling ◽  
Research Results ◽  
Theoretical Substantiation ◽  
Rolling Equipment ◽  
Rolling Production

The analysis of the existing modern problems of rolling production related to the need to take into account the nonstationarity of technological parameters and negative dynamic effects for calculating of power parameters and designing of technology and rolling equipment is performed. Theoretical substantiation and research results confirming their relevance are proposed.

scholarly journals The Impact of Nanoparticles and Moisture Content on Bonding Strength of Urea Formaldehyde Resin Adhesive

2018 ◽  
Vol 69 (3) ◽  
pp. 247-252
Author(s):  
Timuçin Bardak ◽  
Eser Sozen ◽  
Kadir Kayahan ◽  
Selahattin Bardak
Keyword(s):  
Moisture Content ◽  
Bonding Strength ◽  
Urea Formaldehyde ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Resin Adhesive ◽  
The Impact

scholarly journals Influence of Linseed Oil Varnish Admixture on Glauconite Clay Mortar Properties

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5487
Author(s):  
Przemysław Brzyski ◽  
Magdalena Grudzińska
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Mechanical Strength ◽  
Water Resistance ◽  
Linseed Oil ◽  
Sorption Properties ◽  
Vapor Permeability ◽  
Research Results ◽  
Positive Effect

Raw clay is used nowadays in construction as a component of mortars and plasters and as a binder in composites based on straw or shives. It is a material with good sorption properties and vapor permeability, but it is susceptible to shrinkage, is not resistant to water, and also is characterized by low mechanical strength, which makes it impossible to be used, for example, in external plasters. Various additives and admixtures are used to improve selected properties of clay mortars. The article presents the research results and assessment of the effect of glauconite clay mortar modification with an admixture of linseed oil varnish on selected properties. Admixtures in the amounts of 1%, 2%, and 3% in relation to clay weight were used. Flexural and compressive strength, water resistance, shrinkage, drying capacity, density, and porosity of mortar, were tested. The admixture of linseed oil varnish in the amounts used in the investigation had a positive effect on some of the tested properties; regardless of the quantity of the admixture, the modified mortars had better parameters concerning flexural strength, shrinkage reduction, and water resistance than the reference mortar, without admixture.

scholarly journals Justification of optimal design and technological parameters of needle discs of the combined working body

2020 ◽  
Vol 17 ◽  
pp. 00016
Author(s):  
Alexander M. Petrov ◽  
Sergey A. Ivanayskiy ◽  
Mikhail A. Kanaev ◽  
Oleg M. Parfyonov ◽  
Maxim S. Ivanayskiy
Keyword(s):  
Optimal Design ◽  
Quality Indicators ◽  
Soil Tillage ◽  
Technological Parameters ◽  
Research Results ◽  
Soil Cultivation ◽  
Working Bodies ◽  
Rotor Tooth

The aim of the research is to improve soil tillage quality using combined working bodies in surface cultivation. There are various designs of combined tillage units including passive cultivators and active rotor-tooth working bodies cultivating land. However, an analysis of design and technological parameters of modern cultivators shows that they have a cumbersome design, required much metal and their quality indicators do not meet soil cultivation requirements. The article presents results of the studies on the influence of geometric and technological parameters of an additional battery of needle discs on land tillage quality. Using the research results, the land tillage has been improved and combined working bodies have been developed.

The Analysis of Finishing Tooling Influence on Contact Fatigue Researched by Profilometer

2013 ◽  
Vol 199 ◽  
pp. 117-122
Author(s):  
Wojciech Labuda ◽  
Adam Charchalis
Keyword(s):  
Surface Roughness ◽  
Surface Layer ◽  
Contact Fatigue ◽  
Roughness Coefficient ◽  
304L Stainless Steel ◽  
Technological Parameters ◽  
Research Results ◽  
Burnishing Process ◽  
Relative Hardness ◽  
Surface Layer Quality

The article presents the research results referring to the analysis of the influence of finish treatment ( lathing, grinding, burnishing) on the contact fatigue of steel applied to marine pump shafts. The research was performed on a roller 40 mm in diameter made of 304L stainless steel. Within the research, the optimalization of burnishing technological parameters was conducted on account of the minimalization of Ra surface roughness coefficient as well as the maximalization of SU degree of surface layer relative hardness [. The multi criteria optimalization conducted by min-max method [ with regard to minimum surface roughness as well as maximum degree of surface layer hardness demonstrated that burnishing process should be carried out at the following technological parameters: burnishing force 1.1 kN, burnishing speed 35 m/min, feed 0.13 mm/rev. In addition, the influence of the burnisher passes number on the surface layer quality was determined [.The paper will present the research results of contact fatigue examination of samples after finish machining.

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