Vibration characteristic of rubber isolation plate-shell integrated concrete liquid-storage structure

Xuansheng Cheng,Lei Qi,Shanglong Zhang,Yiting Mu,Lingyu Xia 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.81 No.6

To obtain the seismic response of lead-cored rubber, shape memory alloy (SMA)-rubber isolation Plate-shell Integrated Concrete Liquid-Storage Structure (PSICLSS), based on a PSICLSS in a water treatment plant, built a scale experimental model, and a shaking table test was conducted. Discussed the seismic responses of rubber isolation, SMA-rubber isolation PSICLSS. Combined with numerical model analysis, the vibration characteristics of rubber isolation PSICLSS are studied. The results showed that the acceleration, liquid sloshing height, hydrodynamic pressure of rubber and SMA-rubber isolation PSICLSS are amplified when the frequency of seismic excitation is close to the main frequency of the isolation PSICLSS. The earthquake causes a significant leakage of liquid, at the same time, the external liquid sloshing height is significantly higher than internal liquid sloshing height. Numerical analysis showed that the low-frequency acceleration excitation causes a more significant dynamic response of PSICLSS. The sinusoidal excitation with first-order sloshing frequency of internal liquid causes a more significant sloshing height of the internal liquid, but has little effect on the structural principal stresses. The sinusoidal excitation with first-order sloshing frequency of external liquid causes the most enormous structural principal stress, and a more significant external liquid sloshing height. In particular, the principal stress of PSICLSSS with long isolation period will be significantly enlarged. Therefore, the stiffness of the isolation layer should be properly adjusted in the design of rubber and SMA-rubber isolation PSICLSS.

Blends of Silicone Rubber and Liquid Crystalline Polymer

Shivakumar E.,Das C. K.,Pandey K. N.,Alam S.,N.Mathur G. The Polymer Society of Korea 2005 Macromolecular Research Vol.13 No.2

Blends of silicone rubber (VMQ) and liquid crystalline polymer (LCP) were prepared by the melt mixing technique. Mechanical, XRD, thermal and dynamic mechanical investigations are reported for the pure silicone rubber and blends. The mechanical properties, viz. the tensile strength, tear strength and elongation at break, of the silicone rubber decreased with the addition of LCP. The SEM study on the tensile fractured surface of the blends revealed that they had a two phase structure, and that the failure was mainly due to fiber pull out, which suggests that the VMQ and LCP are incompatible in all of the proportions examined in this study. However, the FTIR study shows that there was a partial interaction between the VMQ and LCP, but which may not be sufficient to grip the fibrils under the applied load. In the XRD analysis, it was observed that the crystalline structure of the silicone rubber deteriorated in the presence of LCP. The DMA study suggested that the storage modulus of the silicone rubber was improved with the addition of LCP, due to the high modulus of the LCP phase. The thermal stability of the silicone rubber was greatly reduced by the addition of LCP, due to the latter having a thermal stability lower than that of silicone rubber.

Carbon Nanotubes Modified by Ionic Liquid and Its Effect on Properties of Silicon Rubber Composites

Yuan Jing,Guangyi Lin,Dongmei Xiao,Limeng Zhu 한국고분자학회 2024 폴리머 Vol.48 No.2

In this paper, multi-walled carbon nanotubes (MWCNTs) were modified using ionic liquids (ILs), and silicone rubber/carbon nanotube composites were prepared. The surface of carbon nanotubes is coated with a layer of ionic liquid by non-covalent bond modification, and the van der Waals force between the carbon nanotubes is reduced to achieve the purpose of improving their dispersibility. The electrical conductivity of silicone rubber/carbon nanotube composites prepared by modified carbon nanotubes is improved. The dispersion of modified carbon nanotubes in silicone rubber matrix and the interface interaction between carbon nanotubes and silicone rubber are analyzed by rubber process analyzer and scanning electron microscopy (SEM) tests. The effects of modified carbon nanotubes on electrical conductivity, mechanical properties and electromagnetic shielding properties of silicone rubber composites were studied. The results show that the dispersion of carbon nanotubes in silicone rubber matrix is improved effectively through the modification of ionic liquid, the conductive property of the composite is improved, the electromagnetic wave reflection of the composite is increased, and the electromagnetic shielding efficiency of the composite is improved, and the shielding efficiency is up to 26 dB.

Rubber Toughened Epoxy

Ratna, D.,Banthia, Ajit K. The Polymer Society of Korea 2004 Macromolecular Research Vol.12 No.1

Toughening of epoxy resins for improvement of crack resistance has been the subject of intense research interest during the last two decades. Epoxy resins are successfully toughened by blending with a suitable liquid rubber, which initially remains miscible with epoxy and undergoes a phase separation in the course of curing that leads to the formation of a two-phase microstructure, or by directly blending preformed rubbery particle. Unlike the situation for thermoplastics, physical blending is not successful for toughening epoxy resins. Recent advances in the development of various functionalized liquid rubber-based toughening agents and core-shell particles are discussed critically in this review.

가황시 열매체가 고무제품의 온도분포에 미치는 영향 분석

김태호(Tae-Ho Kim),전승경(Seung-Gyeong Jeon),박현호(Hyun-Ho Park),김준형(Joon-Hyung Kim) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11

Rubber vulcanization is a process of adding elasticity property to a rubber by supplying external or internal heat in rubber. Vulcanization is very dependent upon the property of material, the size and shape of product, various equipments, and so on; especially, the vulcanization equipment is important to increase the efficiency of the heat consumption because it is directly related with the heat supply. Vulcanization equipments are mainly divided into two types, non-continuous and continuous ones. In the viewpoint of the high efficiency of the heat usage as wells as saving the time between processes, the continuous vulcanization equipments are recommended. In this paper, the calculation analysis was mainly carried out about continuous vulcanization equipments by changing heating mediums, the hot air velocity and power. It was known that the performance of vulcanization increased with hot air velocity and power. It was seen that the LCM type equipment is superior to HAV type one for abruptly increasing the temperature within rubber.

Design, fabrication and characterization of xanthan gum/liquidloaded porous natural rubber film

Thawatchai Phaechamud,Nutdanai Lertsuphotvanit,Pongsathorn Issarayungyuen,Takron Chantadee 한국약제학회 2019 Journal of Pharmaceutical Investigation Vol.49 No.1

Porous natural rubber (NR) films were prepared with blocked natural rubber by solvent casting method using dichloromethane as the solvent. The various amount of xanthan gum (0–40 phr) was blended in 75 phr triethyl citrate or glycerin-loaded NR cast films. Xanthan gum markedly promoted the water sorption of these composite films. The proper compatibility of the component employed in these composite NR films was confirmed by X-ray diffractometry, thermogravimetry and differential scanning calorimetry. Although the porosity of composite NR films decreased when xanthan gum was added xanthan gum amount did not significantly affect the mechanical properties, wettability and degradability. The 20 phr xanthan gum was selected as the optimum amount to modify the liquid-loaded NR films for further as wound dressing.

EPDM with Biochar, Carbon Black, Aramid Pulp and Ionic Liquidcompatibilized Aramid Pulp

Vinícius Demétrio da Silva,Micaela Dani Ferrari,Rosmary Nichele Brandalise,Edilson Valmir Benvenutti,Henri Stephan Schrekker,Sandro Campos Amico 한국섬유공학회 2021 Fibers and polymers Vol.22 No.4

Carbon black (CB) is a fossil fuel-derived product widely used as reinforcement in the rubber industry despite itspollution potential and its high energy-demanding production. Biochar, on the other hand, is a renewable source of carbonrecently studied for the partial substitution of CB in elastomeric materials. Aramid pulp/fibers have also been used in avariety of applications in this sector, usually after a surface treatment. In this work, the use of aramid pulp (AP) and biochar inthe preparation of ethylene propylene diene monomer (EPDM) composites and hybrid composites has been studied. The 1-nbutyl-3-methylimidazolium methanesulfonate ionic liquid (IL) was used as compatibilizer in AP, and the rubber-fillerinteraction was studied via thermal, rheometric, mechanical, and swelling analyses. The biochar-EPDM and the referenceCB-EDPM compounds showed similar hardness, modulus at 50 % strain and tear strength results. Among the tested fillers,AP was identified as the most effective to obtain EPDM composites with enhanced properties. A synergistic effect of biocharand IL-treated AP was found, resulting in higher tensile strength for the hybrid formulation (EPDM/Bio05AP05IL)compared to those with just biochar or CB, and reasonable strain at break. In all, the hybrid composites of EPDM reinforcedwith biochar and AP showed the potential to partially or fully replace CB formulations.

A Solid State Actuator Based on the PEDOT/NBR System: Effect of Anion Size of Imidazolium Ionic Liquid

Cho, M. S.,Seo, H. J.,Nam, J. D.,Lee, Y.,Son, Y. K. TaylorFrancis 2007 Molecular Crystals and Liquid Crystals Vol.464 No.1

<P> The fabrication of a dry type conducting polymer actuator is presented using nitrile rubber (NBR) as the base material for the solid polymer electrolyte. A conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), was synthesized on the surface of the NBR by the chemical oxidation polymerization technique, and room temperature ionic liquids (RTIL) based on imidazolium salts, viz. 1-butyl-3-methyl imidazolium X [where X = BF4-, PF6-, (CF3SO2)2N-], were introduced onto the composite film. The effects of the anion size of the ionic liquids on the displacement of the actuator were investigated. The displacement increased with increasing anion-size of the ionic liquids. The cyclic voltammetric responses and the redox switching dynamics of the actuators were studied in different ionic liquids.</P>

Adsorption and photocatalytic degradation of cationic dyes over bismuth ferrite (BFO) intercalated on liquid natural rubber-based hydrogel compound

Mhonishya Krishnamoorthy,Mohamad Azuwa Mohamed,Noor Haida Mohd Kaus,Siti Fairus M. Yusoff 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.116 No.-

A hydrogel-based photocatalyst was employed to remove methylene blue (MB) and safranin dye effluentsfrom wastewater using a liquid natural rubber (LNR)-acrylic acid (AAc) based bismuth ferrite (BFO)hydrogel compound. Response Surface Methodology (RSM) was used in this research to optimize severalparameters for the synthesis of hydrogel compound and adsorptive-photodegradation process. Without apost-treatment separation phase, safranin and MB dye were able to maintain dye removal for up to sixand five cycles with 99% dye removal, respectively, explaining the hydrogel’s stability and adsorptive efficiency. Furthermore, MB and safranin dyes were adsorbed and photodegraded very rapidly under a xenonlamp compared to the dye removal efficacy at dark, proving BFO has aided in the photodegradation processadsorbs further the dye effluents in which the hydroxyl radical (·OH) and superoxide radical (·O2 – )species were responsible for the photocatalytic activity. It has been proposed that safranin and MB dyeeffluent adsorption matches the pseudo-second-order kinetic model and Freundlich isotherm model. Apositive entropy number, S, in thermodynamic analysis indicates that the reaction has become more random,boosting the system’s spontaneity. Meanwhile, it is found that adsorption rate of safranin is highlydependent on pH and is under the influence of inner sphere surface complexes. Thus, the synthesizedLNR-g-MaH/AAc-BFO hydrogel compound in this study has shown excellent performance in the removalof dye effluents for the wastewater treatment process with enhanced stability.

The Effects of Liquid Butadiene Rubber and Resins as Processing Aids on the Physical Properties of SSBR/Silica Compounds

( Muhammet Iz ),( Donghyuk Kim ),( Kiwon Hwang ),( Woong Kim ),( Gyeongchan Ryu ),( Sanghoon Song ),( Wonho Kim ) 한국고무학회 2020 엘라스토머 및 콤포지트 Vol.55 No.4

Highly aromatic (HA) oils are common processing aids used in tire tread compounds. However, they often bleed and evaporate from the vulcanizates during tire use. Thus, the mechanical and dynamical properties of the tire decrease. To overcome this problem, we investigated nonfunctionalized liquid butadiene rubber (LBR-305, Kuraray) and center-functionalized liquid butadiene rubber (C-LqBR), polymerized by anionic polymerization. In addition to the liquid butadiene rubbers, p-tert-octylphenol (P-Resin) and C5 hydrocarbon (H-Resin) tackifier resins, which can induce entanglement of rubber compounds, were researched as a processing aid to solve the bleeding problem. Liquid butadiene rubbers have significantly reduced extraction loss by crosslinking with the main rubber chain. They have also increased the abrasion resistance and showed similar or better mechanical and dynamical properties against HA oils. However, resin compounds did not show differences in extraction loss compared to HA oil compounds; instead, they showed increased wet traction.