• 접착 및 계면
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• 제6권3호
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• pp.19-25
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• 2005

합성 고무계 점착제는 일반적으로 SIS나 SBS 블록 공중합체와 점착부여수지, 가소제, 기타 첨가제를 함유한다. SIS/SBS 계 점착제는 우수한 접착력에도 불구하고 내용제성이나 내열성이 낮아서 그 사용에 한계가 있다. 이에 이러한 단점을 보완하고자 SIS/SBS 점착제에 가교제, 광개시제를 주성분으로 하는 자외선 경화 시스템을 도입하였다. 제조된 점착제는 thiol-ene 광중합 반응에 의해 가교하였으며 점착제의 프로브 택(probe tack), 박리강도(peel strength) 전단접착파괴온도(shear adhsion failure temperature, SAFT)를 측정하여 UV 경화형 점착특성을 고찰하였다. 또한 UV 경화형 점착제의 택 성질을 프로브 택을 이용하여 프로브 재료별, 점착제의 두께별의 영향을 살펴보았고 접촉각 측정을 통해 점착제 표면 변화를 살펴보았다.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2833-2836
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• 2009

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.310-313
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• 1987

A dianion-mediated dialkylation reaction provides a variety of propellanes. 12-Thia[4.4.3] propel-3-ene, 3-(N-benzyl)-2,4-dioxotricyclo[3.3.3.0] decane and 3-(N-benzyl)-2,4-dioxotricyclo[3.3.3.0] nonane were prepared by this dianion ring annulation methodology.

• Elastomers and Composites
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• 제52권3호
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• pp.173-179
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• 2017

Side-chain liquid crystalline polymers having polysiloxane skeletons were synthesized by a thiol-ene reaction, using two kinds of mesogenic groups: a cholesteryl group for induction into a cholesteric liquid crystal phase and a triazomesogenic group for imparting light-sensitivity. All the synthesized polymers were crystalline, except the one with a single cholesteryl group. Crystallinity, glass transition temperature, and melt transition temperature increased with increasing content of the azomesogenic group. The polymer (P-C10A0) with a single cholesteryl group has a cholesteric phase, the one (P-C0A10) with a single azomesogenic group has a smectic phase, and those with both types of mesogenic groups showed both smectic and cholesteric phases. The temperature ranges of the two liquid crystalline phases in the co-polymers were independent of the contents of the two types of mesogenic groups. The rate of photoisomerization of the light-sensitive azobenzene group in the polymer decreased with increasing azobenzene content due to steric hindrance between the azomesogenic groups.

• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.961-966
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• 1994

Oligomerization of phenylacetylene is catalyzed by $Rh(ClO_4)(CO)(PPh_3)_2$ (Rh-1), $[Rh(CO)(PPh_3)_3]ClO_4$ (Rh-2), $[Rh(COD)L_2]ClO_4 (L_2=(PPh_3)_2$, Rh-3; $(PPh_3)(PhCN)$, Rh-4; $(PhCN)_2$, Rh-5), $[Rh(C_3H_5)(Cl)(CO)(SbPh_3)_2]ClO_4$ (Rh-6), $[Ir(COD)L_2]ClO_4 (L_2=(PPh_3)_2$, $Ir-1; (PPh_3)(PhCN)$, $Ir-2; (PhCN)_2$, Ir-3; (AsPh_3)(PhCN)$, $Ir-4; Ph_2PCH_2CH_2PPh_2$, Ir-5; COD, Ir-6 and 2,2'-dipyridyl, Ir-7), $Ir(ClO_4)(CO)(PPh_3)_2$, $Ir-8, [Ir(PhCN)(CO)(PPh_3)_2]ClO_4$, Ir-9 to produce dimerization products, 1,3-diphenylbut-1-yn-3-ene, 1, (E)-1,4-diphenylbut-1-yn-3-ene, 2 and (Z)-1,4-diphenylbut-1-yn-3-ene, 3, and cyclotrimerization products, 1,3,5-triphenylbenzene, 4 and 1,2,4-triphenylbenzene, 5. Product distribution of the oligomers varies depending on various factors such as the nature of catalysts, reaction temperature, counter anions and excess ligand present in the reaction mixtures. Increasing reaction temperature in general increases the yield of the cyclotrimerization products. Exclusive production of dimer 1 and trimer 4 can be obtained with Ir-1 at 0 $^{\circ}$C and with Ir-2 in the presence of excess PhCN (or $CH_3CN$) at 50 $^{\circ}$C, respectively. Dimer 2 (up to 81%) and trimer 5 (up to 98%) are selectively produced with Rh-1 at 50 and 100 $^{\circ}$C respectively. Production of 3 is selectively increased up to 85% by using $PF_6$- salt of $[Ir(COD)(PPh_3)_2]$+ at 25 $^{\circ}$C. Addition of $CH_3I$ to Rh-1 produces $CH_3PPh_3^+I-$ and increases the rate of oligomerization(disappearance of phenylacetylene). Among the metal compounds investigated in this study, Ir-1 catalyzes most rapidly the oligomerization where the catalytically active species seems to contain lr(PPh3)2 moiety. The stoichiometric reaction of phenylacetylene wth Ir-9 at 25 $^{\circ}$C quantitatively produces hydridophenyl-ethynyl iridium(III) complex, $[lr(H)(C{\equiv}CPh)(PhCN)(CO)(PPh_3)_2]ClO_4$ (Ir-11), which seems to be an intermediate for the oligomerization.

• Elastomers and Composites
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• 제48권1호
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• pp.10-17
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• 2013

선형 poly(ethylene-ter-1-hexene-ter-divinylbenzene) 소프트 탄성체 블럭내의 styrene 관능기로부터 poly(t-butylstyrene)하드 블록을 graft-from 음이온 중합을 통해 고온에서 사용 가능한 기능성 폴레올레핀 열가소성 탄성체인 polyolefin-g-poly(t-butylstyrene)을 합성하였다. sec-BuLi/TMEDA와 styrene 단위로부터 반응에 의하여 100% 수율의 음이온 개시 자리를 만들고 4-tert-butylstyrene을 graft-from 중합시켜 10,000~30,000 g/mol 분자량을 가지는 블록을 합성함으로서, 고온 $T_g$를 가지는 폴리올레핀 그라프트 고분자를 얻을 수 있었다. 단량체 함량과 중합시간에 따라 그라프트 분자량이 비례하여 증가하는 효과적인 리빙 중합방법임을 확인하였다. 사슬 말단에 다수의 수산기가 도입된 폴리올레핀 TPE의 합성방법으로서, 리빙 그라프트 고분자 사슬에 계속하여 isoprene을 블록 중합하여 얻어진 polyolefin-g-[poly(t-butylstyrene)-b-high vinyl polyisoprene]의 비닐기와 2-mercaptoethanol간의 thiol-ene 클릭 반응을 이용하는 방법을 통해 진행하였다. 연구 결과, 높은 $T_g$(> $145^{\circ}C$)를 갖는 정밀 제어된 기능성 그라프트 형태의 폴리올레핀 기반 TPE를 합성하는 방법을 확립하였다.

• Macromolecular Research
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• 제17권5호
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• pp.319-324
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• 2009

A new $\pi$-conjugated polymer, poly[(2-methoxy-(5-(2-(4-oxyphenyl)-5-phenyl-1,3,4-oxadiazole)-hexyloxy))-1,4-pheny1ene-1,2-etheny1ene-alt-(10-hexyl-3,7-phenothiazine )-1,2-ethenylene] (PTOXDPPV), was synthesized by the Heck coupling reaction. The electron transporting unit, conjugated 1,3,4-oxadiazo1e (OXD), is attached on the main chain via linear 1,6-hexamethylenedioxy chain. The band gap and photoluminescence (PL) maximum of PTOXDPPV are 2.35 eV and 565 nm, respectively. These values are very close to those of po1y[(2,5-didecyloxy-1,4-phenylene-1,2-etheny1ene )-alt-(l0-hexyl-3,7-phenothiazine)-1,2-ethenylene] (PTPPV), which does not have OXD pendant. The estimated HOMO energy level of PTOXDPPV was -4.98 eV, which is very close to that of PTPPV (-4.91 eV). The maximum wavelength of EL device based on PTOXDPPV and PTPPV appeared at 587 and 577 nm, respectively. In the PL and EL spectrum, the emission from OXD pendant was not observed. This indicates that the energy transfer from OXD pendants to main chain is occurred completely. The EL device based on PTOXD-PPV (ITO/PEDOT/PTOXDPPV/AI) has an efficiency of 0.033 cd/A, which is significantly higher than the device based on PTPPV (ITO/PEDOT/PTPPV/AI) ($4.28{\times}10^{-3}\;cd/A$). From the results, we confirm that the OXD pendants in PTOXDPPV facilitate hole-electron recombination processes in the emissive layer effectively.

• 대한화학회지
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• 제38권1호
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• pp.80-86
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• 1994

Bruceantin유사체 전합성의 중요한 중간체인 ethyl $({\pm})$-8-oxo-10-oxa-l'H-spiro[1, 3]dioxolane-4,4'-tricyclo [9.2.1.0 1,6]dodec-6-ene-9-carboxylate (7)의 합성경로를 개발하였다. 시작물질로서 ethyl 2-cyclohexanonecarboxylate and methyl vinyl ketone을 사용하여, Robinson annulation, allylic oxidation등을 응용하였으며, regiospecific acylation and the formation of epoxy methano bridge 형성 반응 등이 연구되었다. Actalone (3)의 ketalization 반응에서 새로운 decarboethoxylation 반응을 발견하였으며, 이 반응을 이용하여 3차 알코올과 엔온을 가지고 있는 4,4a,5,6,7,8-Hexahydro-4a-hydroxy-2(3H)naphthalenone (14)를 합성하였다.

• 멤브레인
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• 제23권5호
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• pp.360-366
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• 2013

Poly (vinylidene fluoride) (PVDF) poly (acrylonitrile) (PAN) 중공사막에 친수성 고분자인 poly (vinyl alcohol) (PVA)과 가교제인 poly (acrylic acid) (PAA)을 코팅하여 복합막을 제조하였다. 제조된 막의 투과특성평가를 위해 90 wt% 물-에탄올 혼합액에 대한 투과증발실험을 수행하였으며, 반응온도, PAA용액의 농도, 공급액의 온도변화에 따른 투과도 및 선택도를 측정하였다. 일반적으로 반응온도, PAA용액의 농도가 증가할수록 투과도는 낮아지고 선택도는 증가하는 경향을 보였으며, 공급액의 온도가 증가할수록 투과도는 증가하고 선택도는 낮아지는 경향을 보였다. 대표적으로 PVDF중공사 막은 투과도는 PAA 3 wt%, 반응온도 $60^{\circ}C$, 공급액 온도 $70^{\circ}C$에서 $502g/m^2hr$, 선택도는 PAA 11 wt%, 반응온도 $100^{\circ}C$, 공급액 온도 $50^{\circ}C$일 때, 218의 결과를 얻을 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.1033-1037
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• 2008

A copper cyclam-type complex was successfully immobilized onto mesoporous silica SBA-16. Characterization by NIR spectroscopy and TGA analysis confirmed that copper cyclam complex is immobilized onto mesoporous SBA-16. The Cu(II)-Cyclam-SBA-16 was proven to be a good catalyst for oxidation reaction of cyclohexene with conversion up to 77.8% after 13 h reaction and providing a high selectivity to cyclohexenol and 3-hydroperoxycyclohex-1-ene. The results suggest that the copper species play a major role as catalyst via reversible redox cycles as proven by cyclic voltammetry analysis.