scholarly journals Low Viscosity Epoxy Structural Adhesive Cured at Room Temperature for Crack Repair of Subway Tunnel

2021 ◽  
Vol 2101 (1) ◽  
pp. 012047
Author(s):  
Ming Xiao ◽  
Xiaojiang Sun ◽  
Huaqing Rong ◽  
Shuguang Bi ◽  
Jiagong Tang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Poor Performance ◽  
Subway Tunnel ◽  
Adhesive Properties ◽  
Structural Adhesives ◽  
Low Viscosity ◽  
High Adhesion ◽  
Crack Repair ◽  
Amine Curing ◽  
Structural Adhesive

Abstract Epoxy structural adhesive has good mechanical properties, especially high adhesion, low shrinkage rate, and high stability, widely used in steel plate reinforcement, crack repair, bridge splicing, and concrete bonding, etc. However, due to the high cross-linking density and high internal stress after curing, its shortcomings, such as brittleness, the poor performance of fatigue resistance and heat resistance, limit its application in special track engineering. In this work, two kinds of epoxy structural adhesives (EPA-1, EPA-2) with low viscosity and room temperature curing were synthesized by selecting different bisphenol A epoxy resin and active diluent as component A and modified amine curing agent as component B. The results showed that EPA-1 and EPA-2 presented significant toughness compared with the classic construction adhesive (AralditeXH160). The yield strengths of EPA-1 and EPA-2 were 4.88 MPa and 13.13 MPa, and the shear strengths were 11.93 MPa and 13.08 MPa, respectively, showing good adhesive properties. In addition, the viscosities of EPA-1 and EPA-2 were 127 mPa·s and 308 mPa·s, respectively, and their decomposition temperatures were all above ∼280 °C, which indicated that the self-made epoxy structural adhesives could be used for the repair of cracks in the vibration subway tunnel.

scholarly journals Production of modified adhesive composites based on EVA and modified PE

2020 ◽  
pp. 45-47
Author(s):  
M. D. Sizova ◽  
A. N. Zelenetsky ◽  
V. Ya. Ivolgin
Keyword(s):  
Maleic Anhydride ◽  
Polymer Matrix ◽  
Morphological Changes ◽  
Adhesive Properties ◽  
Adhesion Properties ◽  
High Adhesion

An adhesive based on EVA and LDPE is developed which can be used up to 60°C. It was modified by polyisocyanate fragments of a grafted and reticulate nature for structural and morphological changes of the polymer matrix and improvement of physical, mechanical and adhesive properties. For additional compatibilization of the components, LDPE modified with maleic anhydride (MA) was used. High adhesion properties of the obtained composites were confirmed.

scholarly journals Optical and Structural Properties of CdS Quantum Dots Synthesized Using (MW-CBD) Technique

2020 ◽  
pp. 44-52
Author(s):  
Ahmed Ahmed S. Abed ◽  
Sattar J. Kasim ◽  
Abbas F. Abbas
Keyword(s):  
Thin Films ◽  
Quantum Dots ◽  
Room Temperature ◽  
Energy Gap ◽  
Cds Nanoparticles ◽  
Cds Quantum Dots ◽  
Optical Energy Gap ◽  
Glass Substrates ◽  
High Adhesion ◽  
Uv Visible

In the present study, the microwave heating method was used to prepare cadmium sulfide quantum dots CdSQDs films. CdS nanoparticles size average obtained as (7nm). The morphology, structure and composition of prepared CdSQDs were examined using (FE-SEM), (XRD) and (EDX). Optical properties of CdSQDs thin films formed and deposited onto glass substrates have been studied at room temperature using UV/ Visible spectrophotometer within the wavelength of (300-800nm), and Photoluminescence (PL) spectrum. The optical energy gap (Eg) which estimated using Tauc relation was equal (2.6eV). Prepared CdS nanoparticles thin films are free from cracks, pinholes and have high adhesion to substrate.

scholarly journals Synthesis, Characterization, and Visible Light Curing Capacity of Polycaprolactone Acrylate

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Jy-Jiunn Tzeng ◽  
Yi-Ting Hsiao ◽  
Yun-Ching Wu ◽  
Hsuan Chen ◽  
Shyh-Yuan Lee ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
3D Printing ◽  
Visible Light ◽  
Room Temperature ◽  
Low Viscosity ◽  
Nuclear Magnetic Resonance Spectra ◽  
Light Curing ◽  
Soft Tissue Engineering ◽  
The Fourier Transform ◽  
Visible Light Curing

Polycaprolactone (PCL) is drawing increasing attention in the field of medical 3D printing and tissue engineering because of its biodegradability. This study developed polycaprolactone prepolymers that can be cured using visible light. Three PCL acrylates were synthesized: polycaprolactone-530 diacrylate (PCL530DA), glycerol-3 caprolactone triacrylate (Glycerol-3CL-TA), and glycerol-6 caprolactone triacrylate (Glycerol-6CL-TA). PCL530DA has two acrylates, whereas Glycerol-3CL-TA and Glycerol-6CL-TA have three acrylates. The Fourier transform infrared and nuclear magnetic resonance spectra suggested successful synthesis of all PCL acrylates. All are liquid at room temperature and can be photopolymerized into a transparent solid after exposure to 470 nm blue LED light using 1% camphorquinone as photoinitiator and 2% dimethylaminoethyl methacrylate as coinitiator. The degree of conversion for all PCL acrylates can reach more than 80% after 1 min of curing. The compressive modulus of PCL530DA, Glycerol-3CL-TA, and Glycerol-6CL-TA is 65.7±12.7, 80.9±6.1, and 32.1±4.1 MPa, respectively, and their compressive strength is 5.3±0.29, 8.3±0.18, and 3.0±0.53 MPa, respectively. Thus, all PCL acrylates synthesized in this study can be photopolymerized and because of their solid structure and low viscosity, they are applicable to soft tissue engineering and medical 3D printing.

Adhesion Properties between Swollen Hydrogels in Air

2005 ◽  
Vol 897 ◽  
Author(s):  
Daisuke Sakasegawa ◽  
Takaya Sato ◽  
Motoaki Goto ◽  
Atsushi Suzuki
Keyword(s):  
Room Temperature ◽  
Normal Force ◽  
Adhesion Force ◽  
Point Contact ◽  
Sodium Acrylate ◽  
Evaluation Technique ◽  
Adhesive Properties ◽  
Adhesion Properties ◽  
Aluminum Ions ◽  
Separation Velocity

AbstractAdhesion between swollen hydrogels was studied using a simple tack-evaluation technique by a point contact in air at room temperature. The hydrogel used here was poly(sodium acrylate) (PSA) gel physically cross-linked by aluminum ions. The adhesion force and the separation energy showed a power-law increase with separation velocity, normal force, and waiting period　prior to separate. Effects of the degrees of protonation in PSA as well as of dehydration on the adhesive properties are also presented. The results are discussed in terms of the surface molecular interaction and the bulk elastic and viscous properties.

Two Component Room Temperature or Induction Curable Structural Adhesives for Automotive Applications

1995 ◽  
Author(s):  
John M. Baldwin ◽  
Virginia C. Marhevka ◽  
Kent S. Tarbutton ◽  
Elaine M. Yorkgitis
Keyword(s):  
Room Temperature ◽  
Automotive Applications ◽  
Structural Adhesives ◽  
Two Component

scholarly journals Concentration of the carcinogenic material in a Venezuelan spindle oil by simultaneous molecular distillation and chromatographic adsorption

1944 ◽  
Vol 43 (4) ◽  
pp. 248-251
Author(s):  
J. M. Twort ◽  
R. Lyth
Keyword(s):  
Molecular Distillation ◽  
Room Temperature ◽  
Adsorption Process ◽  
Active Material ◽  
Animal Experiments ◽  
Practical Work ◽  
Inert Material ◽  
Crystalline Solids ◽  
Low Viscosity ◽  
Adsorption Processes

Some concentration of the carcinogenic material in a Venezuelan spindle grade oil has been affected by simultaneous molecular distillation, and further concentration has also been accomplished by subjecting one of the more carcinogenic of these distillates to chromatographic adsorption. Animal experiments revealed that this distillate was about twice as carcinogenic as the oil from which it was derived. Two small fractions obtained from this distillate by chromatographic adsorption were painted on the skin of a few mice and both appeared to be appreciably more carcinogenic than the distillate from which they were derived. Further experiments with one of these fractions and the distillate, not yet completed, indicate that this fraction is at least five times as strong as the distillate from which it was derived. Thus by a combination of molecular distillation and chromatographic adsorption processes we have obtained a fraction about ten times as strong as the original oil. During the chromatographic adsorption process large quantities of colourless, low index, inert or almost inert material of relatively low viscosity have been separated from the highly coloured active remainder. It would appear that the most active material is highly viscous at room temperature, but its activity may be due to the presence in it of crystalline solids.In conclusion we wish to express our thanks to our steward, Mr L. Norburn, for his valuable assistance in the practical work.

scholarly journals Design of Highly Adhesive and Water-Resistant UV/Heat Dual-Curable Epoxy–Acrylate Composite for Narrow Bezel Display Based on Reactive Organic–Inorganic Hybrid Nanoparticles

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2178
Author(s):  
Jun Hyup Lee
Keyword(s):  
Adhesion Strength ◽  
Sol Gel ◽  
Hybrid Nanoparticles ◽  
Epoxy Acrylate ◽  
Inorganic Hybrid ◽  
Low Viscosity ◽  
Information Displays ◽  
Heat Curing ◽  
High Adhesion ◽  
Acrylate Resin

To attain the narrow bezel characteristic of information displays, functional sealing composite materials should possess high adhesion strength and water barrier performance due to their narrow line widths. In this study, highly adhesive UV/heat dual-curable epoxy–acrylate composites with outstanding water-resistant performance have been proposed using photoreactive organic–inorganic hybrid nanoparticles that can react with an acrylate resin, creating a crosslinked nanoparticle network within the sealing composite. The hybrid nanoparticles consisted of reactive methacrylate groups as a shell and an inorganic core of silica or aluminum oxide, and were facilely synthesized through sol–gel reaction and chemisorption process. The curing characteristics, adhesive strength, and moisture permeability of the proposed sealing composite have been compared to those of a conventional epoxy–acrylate composite containing inorganic silica particles. The composites including hybrid nanoparticles exhibited high UV and heat curing ratios owing to the numerous methacrylate groups on the nanoparticle surface and high compatibility with organic resins. Moreover, the proposed sealing composite showed high adhesion strength and extremely low water permeability due to the creation of densely photocrosslinked network with matrix resins. In addition, the sealing composite exhibited excellent narrow dispensing width as well as relatively low viscosity, suggesting the potential application in narrow bezel display.

Plasticization of Rubber in the Form of Latex

1954 ◽  
Vol 27 (1) ◽  
pp. 271-276 ◽  
Author(s):  
Marc Conté
Keyword(s):  
Hydrogen Peroxide ◽  
Chemical Reactions ◽  
Room Temperature ◽  
Ph Value ◽  
Inhibitory Effect ◽  
Rubber Latex ◽  
Adhesive Properties ◽  
Harmful Effects ◽  
Latex Rubber

Abstract When in the form of latex, rubber can be oxidized by thiols under hot conditions. The reaction apparently proceeds by the same mechanism as that characteristic in the action of peptizing agents on rubber during mastication. The results obtained confirm the hypothesis that the thiol is transformed quantitatively into the corresponding disulfide, with resultant oxidation of the rubbert. This transformation is a function of the pH value, and the best results are obtained when the pH value is around 4 and in the absence of NH4 ions (which have an inhibitory effect). Latex preparations of this type can be utilized for studying the chemical reactions of rubber in emulsion and for the preparation of rubber derivatives which are more soluble than those prepared from rubber latex which has not been degraded. In addition, such latex preparations are excellent adhesives which, in contrast to already known products (latex treated with hydrogen peroxide or other peroxides), give a sticky film by simple drying at room temperature. In this way heating can be avoided in cases where it has harmful effects and where the use of an oven is inconvenient. Finally, this type of latex is more adaptable to certain direct applications, both because of the superior adhesive properties of the rubber and because, with a relatively plastic coagulum, mastication is easier.

The effect of spotwelds and structural adhesives on static and dynamic characteristics of vehicle body design

2021 ◽  
pp. 095440702110044
Author(s):  
Gozde Tuncer ◽  
Deniz Mansouri ◽  
Polat Şendur
Keyword(s):  
Topology Optimization ◽  
Element Model ◽  
Vehicle Body ◽  
Functional Requirements ◽  
Performance Indices ◽  
Potential Cost ◽  
Vehicle Performance ◽  
Structural Adhesives ◽  
Body Design ◽  
Structural Adhesive

Spotwelding and structural adhesive applications are two important processes in the automotive industry as they are closely associated with the functional requirements, weight, and cost of the vehicle. Even though there is a vast body of literature on their mathematical models, the effect of these processes on key vehicle performance indices and optimization is rather limited. Besides, the weight benefit of these processes in terms of functional requirements has not been investigated. There are multiple objectives of the paper to fill this gap: (i) to quantify the effect of structural adhesives on the key performance indices (KPIs) of a vehicle body, (ii) to rank the components based on their gauge sensitivities for body KPIs using topometry optimization, (iii) to assess the weight impact of the structural adhesive applications using the gauge sensitivity results, (iv) to determine the optimum layout of the structural adhesive applications using topology optimization, (v) to present a methodology for automotive original equipment manufacturers (OEMs) to determine the “critical welds” on the vehicle body and reduce the number of spotwelds as a potential cost reduction action. For this purpose, a validated finite element model of 2010 Toyota Yaris has been used. Optimization of the structural adhesives and spotwelds was carried-out using SIMP (Solid Isotropic Material with Penalization) based topology optimization. The thickness of each panel is ranked using topometry optimization results. Automotive OEMs can use the proposed methodology to optimize the structural adhesives or spotwelding processes in their product development cycle.

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