• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1407-1409
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• 2009

• Journal of Aerospace System Engineering
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• v.7 no.4
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• pp.36-41
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• 2013

In order to improve incombustibility of EPDM(Ethylene propylene diene monomer)-based rubber, inorganic materials as $Al(OH)_3$ and $Sb_2O_3$ were added. The mechanical and thermal properties have been measured for vulcanized rubber loaded with different concentrations of $Al(OH)_3$ and $Sb_2O_3$. As inorganic material contents increases from 5phr to 30phr, the specific gravity and hardness increase while elongation at break decreases. This study performed incombustibility test and thermal analysis through TGA(Thermogravimetric Analyzer). As a results, incombustible and thermal properties of EPDM-based rubber were improved as $Al(OH)_3$ and $Sb_2O_3$ contents increase.

• Archives of Pharmacal Research
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• v.22 no.6
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• pp.575-578
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• 1999

Derivatives of elema-1,3-diene were synthesized in several steps as polar analogs of $\beta$-elemene, antitumor agent under clinical phase. The lactone ring of compound 1 was opened by LiAlH4 to give diol 2 which was selectively protected by TBDPSCI. After acetylation of the secondary alcohol, the acetylated product was ozonolyzed and reduced to give elemene derivative 4 which was converted to diolefin 8 via selenides subsequent deprotection by tetrabutylammonium fluoride gave two compounds 9, 10.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1103-1107
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• 1994

Interaction of triethylsilane and diphenylsilane ($Ph_2$$SiH_2$, $Ph_2$$SiD_2$) with the surfaces of rhodium has been examined by trapping the reaction intermediates with 2,3-dimethyl-l,3-butadiene. 1,4-Hydrosilylation of the diene is predominantly observed to occur under mild condition over the rhodium catalyst. It is inferred from the product analyses that silylene and silyl radicals bonded to rhodium surfaces are the intermediates for addition of silylene to the diene, and for 1,4-hydrosilylation, respectively.

• Journal of the Korean Chemical Society
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• v.37 no.8
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• pp.757-764
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• 1993

The photochemical precursors, 1,1,1,3,3,3-hexamethyl-2-phenyltrisilane(2) and 2,3-dicarbomethoxy-1,4,5,6,7-pentaphenyl-7-silanorbornadiene(5) were synthesized in the yield of 10% and 73%, respectively. Irradiation of 2 at 254 nm in the presence of triethylsilane gave 1,1,1-triethyl-2-phenyldisilane (6) in 44% yield which was the product of phenylsilylene insertion into the Si-H bond. Irradiation of 2 in the presence of diphenylacetylene gave 1-phenyl-1-silacyclopenta-2,4-diene(4) in 68% yield together with 1,2-diphenyl-1,2-disilacyclohexa-2,5-diene(26%) which were formed from [2＋2] addition of the silacyclopropene to diphenylacethylene and formed from dimerization of silacyclopropene, respectively. From the neat photolysis of precursor 2,1,5-dihydrosilanthrene(11), intermolecular C-H insertion product of phenylsilylene and 1,2-diphenyltrisilane(12), Si-H insertion product of phenylsilylene to the precursor were obtained in the yield of 5% and 7%, respectively. In the same experimental condition, both photolyses of 5 in the presence of triethylsilane and methanol showed that the intramolecular 1,5-sigmatropic rearrangement of precursor 5 to give the formation of silylenolether was more favorable process than the generation of phenylsilylene.

• Elastomers and Composites
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• v.48 no.3
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• pp.195-200
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• 2013

The main objective of this study is to improve abrasion resistance and wet slip resistance of thermoplastic polyurethane (TPU) by blending with ethylene-propylene-diene monomer rubber (EPDM) or polybutadiene rubber (BR) for the application of the footwear outsole materials. With addition of 10 wt% of EPDM or BR, TPU/EPDM and TPU/BR blends exhibited higher NBS abrasion resistance, tensile properties and wet slip resistance than TPU. However, with further increasing content of EPDM and BR, abrasion resistance and tensile properties of the blends decreased. Improvement in abrasion resistance and tensile properties with 10 wt% of addition of EPDM or BR may be due to better microphase separation of TPU.

• Natural Product Sciences
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• v.26 no.1
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• pp.90-96
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• 2020

Artemisia capillaris Thunb. (Compositae) is a traditional medicinal plant with various pharmacological activities. To elucidate new anti-allergic and anti-inflammatory constituents, the aerial parts of A. capillaries were investigated to afford a new compound, (6E,8E)-6-methylundeca-6,8-diene-2,5,10-trione (17) together with 19 known compounds (1 - 16, 18 - 20). The structures of these compounds were determined by extensive spectroscopic analyses including 1D, 2D NMR, HREIMS, and optical rotation [α]_D. The absolute configuration of compound 2 was determined to be S form for the first time. All isolates (1 - 20) were tested their inhibitory effects on interleukin 2 (IL-2) expression in T cells and NO production in lipopolysaccharide (LPS)-stimulated RAW246.7. Among them, compounds 10, 11, 19, and 20 reduced IL-2 expression in a dose-dependent manner. In addition, compound 10 also inhibited NO production with an IC₅₀ value of 37.3 ± 0.4 μM.

• Polymer(Korea)
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• v.37 no.5
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• pp.571-578
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• 2013

Polyamide12 (PA12) is blended with ethylene propylene diene rubber (EPDM) at various compositions in the presence of maleated EPDM (mEPDM) to afford blend materials having the characteristics of thermoplastic elastomer (TPE). The EPDM/PA12 melt-blends are further irradiated with electron-beam (e-beam) at 0~100 kGy dosage, yielding selective crosslinking between EPDM chains while retaining melt-processibility originated from PA12 phase. mEPDM acts as a compatibilizer and affords additional improvements in mechanical properties of the EPDM/PA12 blend. With 25 kGy of e-beam irradiation and mEPDM, the EPDM/PA12 blends successfully exhibit TPE behaviors with reasonable elastomeric and mechanical properties.

• Polymer(Korea)
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• v.38 no.1
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• pp.62-68
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• 2014

To improve the compatibility of bentonite with rubber matrix, organo-modified bentonite was synthesized with a silane coupling agent, [3-(2-aminoethylamino)propyl]trimethoxysilane (AEAPTMS) in the suspension of bentonite. The structure and characteristics of organo-modified bentonite were investigated using FTIR-spectroscopy, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Ethylene-propylene-diene monomer (EPDM) rubber/organo-bentonite composites were compounded by a two-roll mill. The vulcanization and mechanical properties were studied. Results showed that the concentration of hydrochloric acid and $H_2O$ in the synthesis had significant influence on the modification of bentonite, which further contributed to the properties of the composites. Filled with 20 phr modified bentonite, the tensile strength and elongation at break of the rubber increased from 1.95 to 4.8 MPa and 300% to 500%, respectively.

• Korean Journal of Pharmacognosy
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• v.34 no.1 s.132
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• pp.10-13
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• 2003

This study is to establish the quality control method of Adenophorae Radix. (6R,7R)-E,E-tetradeca-4,12-diene-8,10-diyne-1,6,7-triol (1) isolated from this plant was adequate as an analytical marker. Content of 1 in Adenophorae Radix was $0.006\;{\pm}\;0.003%$ (n = 43). In addition, total ash content was $6.5\;{\pm}\;4.0%$, and loss on drying was $12.1\;{\pm}\;2.1%$.