• Journal of Integrative Natural Science
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• v.9 no.1
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• pp.62-66
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• 2016

To manipulate the mechanical properties of acrylonitrile butadiene rubber (NBR), addition of nano-sized silica on rubber was performed and nano-silica NBR composite (NSR) materials were fabricated by press molding. The effect of volume fraction of silica in the NSR on the spectroscopic and mechanical properties has been studied.

• Elastomers and Composites
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• v.6 no.2
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• pp.73-79
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• 1971

As a series of the studies of EPDM-Polymer blends, the experiments are concentrated to the investigation of the physical properties of the EPDM-SBR blends. The results are shown as follows: 1. Tensile strength decreased with increase in EPDM contents and the decreasing value was good results than NR blending. 2. It was found that the aging were much improved after blending and experiments data was good results than NR blending.

• Elastomers and Composites
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• v.35 no.1
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• pp.38-45
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• 2000

Influence of rubber composition on migration of antiozonants to the surface in ternary rubber-based vulcanizates composed of natural rubber (NR) styrene-butadiene rubber (SBR), and butadiene rubber (BR) was studied. Of the three rubbers, contents of two rudders were same and only the other one content was different (variable rubber) IPPD and HPPD were employed as antiozonants. Migration experiments were performed at $60^{\circ}C$ for 21 days and outdoors for 4 months. Migration rates of the antiozonants increase by increasing the content ratio of the variable rubber in the vulcanizares from NR/SBR/BR=1/1/0.2 to 1/1/1 and then decrease with an increase of the content ratio of the variable rudder from 1/1/1 to 1/1/5. Migration behaviors of the antiozonants in the ternary rudder-based vulcanizates depending on the rubber composition were explained by the intermolecular interactions between rubber and antiozonant, by the solubility difference of the antiozonants for the rubbers, and by the interface formed between dissimilar rubbers in the triblends.

• Elastomers and Composites
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• v.35 no.1
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• pp.53-62
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• 2000

Zinc plated steel tire cords were treated with RF plasma polymerization coating of acetylene or butadiene in order to enhance adhesion to rubber compounds. Plasma polymerization was carried out as a function of plasma power, treatment tune and gas pressure. In order to maximize adhesion, argon plasma etching was performed, with carrier gas such as argon, nitrogen and oxygen, while the adhesion of tire cords was evaluated via TCAT. Best results were obtained from a combination treatment of argon etching (90 W. 10 min, 30 mTorr) and acetylene plasma polymerization coating (10 W, 30 sec, 30 mTorr) with argon carrier gas (25/5:acetylene/argon). These samples exhibited a pull out force of 285N which is comparable to that obtained from the brass plated tire cords (290N).

• Macromolecular Research
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• v.17 no.10
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• pp.776-784
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• 2009

N,N-dimethyldodecylamine (tertiary amine)-modified MMT (DDA-MMT) was prepared as an organically modified layered silicate (OLS), after which styrene-butadiene rubber (SBR) nanocomposites reinforced with the OLS were manufactured via the latex method. The layer distance of the OLS and the morphology of the nanocomposites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). By increasing the amount of N,N-dimethyldodecylamine (DDA) up to 2.5 g, the maximum values of torque, tensile strength and wear resistance of the SBR nanocomposites were increased due to the increased dispersion of the silicate layers in the rubber matrix and the increased crosslinking of the SBR nanocomposites by DDA itself. When SBR nanocomposites were manufactured by using the ternary filler system (carbon black/silica/OLS) to improve their dynamic properties as a tire tread compound, the tan $\delta$(at $0^{\circ}C$ and $60^{\circ}C$) property of the compounds was improved by using metal stearates instead of stearic acid. The mechanical properties and wear resistance were increased by direct substitution of calcium stearate for stearic acid because the filler-rubber interaction was increased by the strong ionic effect between the calcium cation and silicates with anionic surface. However, as the amount of calcium stearate was further increased above 0.5 phr, the mechanical properties and wear resistance were degraded due to the lubrication effect of the excessive amount of calcium stearate. Consequently, the SBR/organoclay nanocomposites that used carbon black, silica, and organoclay as their ternary filler system showed excellent dynamic properties, mechanical properties and wear resistance as a tire tread compound for passenger cars when 0.5 phr of calcium stearate was substituted for the conventionally used stearic acid.

• Journal of Environmental Health Sciences
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• v.30 no.4
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• pp.301-307
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• 2004

1,3-butadiene(DB) is a well-established rodent carcinogen, and a probable carcinogen to humans. This study was investigated the formation of hemoglobin adduct in ICR female mice inhaled with BD for 3 weeks (5 hr/day, 5 days/week). Body weights of mice were significantly low from onward day 4 or 9 of exposure comparing the control. Hemoglobin adducts formed by DB exposure were (N-2-hydroxy-3-butenyl) valine (HB Val adduct) and (N-2,3,4-trihydroxy-butyl)valine(THB Val adduct). The levels of HB Val adducts were 1.8, 3.7 and 6.2 pmol/mg globin for the 500 ppm BD inhalation group, and 5.7, 7.4 and 16.0 pmol/mg globin for the 1000 ppm BD inhalation group, when observed on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week after inhalation exposure, respectively. The levels of THBVal adducts were 32.0, 42.0 and 55.0 pmol/mg globin for the 500 ppm DB inhalation group, and 67.8, 72.7 and 83.5 pmol/mg globin for the 1000 ppm BD inhalation group, when observed on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week after inhalation exposure, respectively. Ratios of THBVal and HBVal adducts were higher at earlier exposure period and lower concentration. Ratios on the $1^{st},\;2^{nd},\;and\;3^{rd}$ week were 17.8, 11.4 and 8.87 for the 500 ppm BD inhalation group, and 11.9, 9.8 and 5.2 for the 1000 ppm BD inhalation group, respectively. In conclusion, THB Val and HB Val adducts were the important hemoglobin adducts in ICR female mice inhaled with BD, and the latter was more appropriate biomarker than the other for biological monitoring of BD exposure.

• Journal of Environmental Health Sciences
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• v.44 no.2
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• pp.160-168
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• 2018

Objectives: The purposes of the study were to investigate hazardous pollutant emissions changes among group 1 carcinogens. The emissions characteristics were compared with national cancer registration statistics. Methods: A survey of group 1 carcinogen hazardous pollutant emissions (trichloroethylene, benzene, vinyl chloride, formaldehyde, 1,3-butadiene, ethylene oxide, chromium and its compounds, 3,3'-dichloro-4,4-diaminodiphenylmethane, chloromethyl methyl ether, arsenic and its compounds, cadmium and its compounds, o-toluidine) was conducted through a homepage for 2001-2015. The emission of hazardous chemicals and the cancer trend analysis for 2001-2015 were performed using the Korean statistical information service through its homepage as a reference. Results: Emissions of more than 95% of the substances listed as group 1 carcinogens over the last five years were made up of trichloroethylene, benzene, vinyl chloride, formaldehyde, 1,3-butadiene, and ethylene oxide. As a result of the comparison of emission results and cancer incidence rates, carcinogen pollutant emissions showed a tendency to decrease continuously. In addition, the incidence of cancer tended to increase, but showed a tendency to decrease from 2012. Conclusion: The results indicate hazardous pollutant emissions have continued to increase. However, no association between emissions and health effects was shown and more research is needed.

• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.555-564
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• 2020

Objectives: To identify and investigate through qualitative and quantitative analysis the hazardous substances generated when compressed wood was burned at a live fire-training center. Methods: Four types of compressed wood that are actually used in live fire training were burned in a chamber according to KS F2271. The gaseous material was sampled with a gas detector tube and conventional personal samplers. Results: 1,3-butadiene, benzene, toluene, xylene, formaldehyde, hydrogen chloride, hydrogen cyanide, ammonia, carbon monoxide, and nitric acid were detected. In particular, 1,3-butadiene (497.04-680.44 ppm), benzene (97.79-125.02 ppm), formaldehyde (1.72-13.03 ppm), hydrogen chloride (4.71-15.66 ppm), hydrogen cyanide (3.64-8.57 ppm), and sulfuric acid (3.85-5.01 ppm) exceeded the Korean Occupational Exposure Limit as measured by sampling pump according to the type of compressed wood. Conclusions: We found through the chamber testing that firefighters could be exposed to toxic substances during live fire training. Therefore, firefighter protection is needed and more research is required in the field.

• Polymer(Korea)
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• v.34 no.2
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• pp.108-115
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• 2010

The effects of acid-treated MWCNT and coupling agent on properties of MWCNT/SBR are investigated in this work. The MWCNTs oxidized using sulfuric and nitric acids were analyzed by the Raman scattering and Fourier transformed infrared spectroscopy(FT-IR). The FT-IR results indicate the presence of -COOH groups in the treated samples, and Raman spectroscopy of the acidtreated MWCNTs further corroborates the formation of surface defect due to the introduction of carboxyl groups. And the nanocomposites reinforced with MWCNTs were characterized extensively using the scanning electron microscopy(SEM), electrical conductivity, thermal conductivity, and tensile properties measurements. The results showed that nanocomposites onto acid-treated MWCNTs enhanced mechanical properties compared to those containing MWCNTs without acid treatment. These findings confirmed the improved interfacial interactions between MWCNTs and SBR arising from the coupling agents. But the electrical and thermal conductivity of nanocomposites decreased due to the chopping and formation of surface defects of MWCNTs.

• Transactions on Electrical and Electronic Materials
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• v.14 no.3
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• pp.133-138
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• 2013

Acrylonitrile-butadiene-styrene (ABS) plastic is a polymer material extensively used in electrical and electronic applications. Nickel (Ni) thin film was deposited on ABS by electroless plating, after its surface was treated and modified with atmospheric plasma generated by means of dielectric barrier discharges (DBDs) in air. The method in this study was developed as a pre-treatment for electroless plating using DBDs, and is a dry process featuring fewer processing steps and more environmentally friendliness than the chemical method. After ABS surfaces were modified, surface morphologies were observed using a scanning electron microscope (SEM) to check for any physical changes of the surfaces. Cross-sectional SEM images were taken to observe the binding characteristics between metallic films and ABS after metal plating. According to the SEM images, the depths of ABS by plasma are shallow compared to those modified by chemically treatment. The static contact angles were measured with deionized (DI) water droplets on the modified surfaces in order to observe for any changes in chemical activities and wettability. The surfaces modified by plasma showed smaller contact angles, and their modified states lasted longer than those modified by chemical etching. Adhesion strengths were measured using 3M tape (3M 810D standard) and by 90° peel-off tests. The peel-off test revealed the stronger adhesion of the Ni films on the plasma-modified surfaces than on the chemically modified surfaces. Thermal shock test was performed by changing the temperature drastically to see if any detachment of Ni film from ABS would occur due to the differences in thermal expansion coefficients between them. Only for the plasma-treated samples showed no separation of the Ni films from the ABS surfaces in tests. The adhesion strengths of metallic films on the ABS processed by the method developed in this study are better than those of the chemically processed films.