• 폴리머
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• 제30권5호
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• pp.432-436
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• 2006

인덴과 메틸인덴 리간드를 가지고 폴리메틸렌 다리결합으로 구성된 두 금속 CGC (constrained geometry complexes) 촉매를 합성하여 에틸렌과 스티렌 공중합을 행하였다. 촉매 구조에 따른 공중합 활성과 공중합체의 구조 및 열적 성질을 조사하였다. 12-메틸렌 및 9-메틸렌 다리결합을 가진 촉매의 환성은 상업용 CGC 촉매와 6-메틸렌 다리결합을 가진 촉매의 활성보다 4배 이상 높게 나타났는데, 이는 6-메틸렌 다리결합은 입체적으로 중심금속간은 인접한 거리에 위치하게 되어 입체장애에 의해 촉매활성이 감소하게 된다. 다리결합의 길이가 긴 두 금속촉매를 사용하여 제조한 공중합체의 스티렌 함량이 6-45 mol%로 나타났으며, 단량체 공급비([Styrene]/[Ethylene])가 5.0 이상에서는 다리결합의 길이가 긴 촉매로 얻은 공중합체의 $T_m$이 관찰되지 않는 비결정의 공중합체가 생성되었으며, 스티렌의 함량이 증가할수록 공중합체의 $T_m$은 급격히 감소하여 스티렌 함량이 약 11mol% 이상에서는 결정성이 없는 랜덤 공중합체가 생성되었다. C-NMR로 공중합체의 미세구조를 분석한 결과 스티렌 블록이 존재하지 않는 랜덤 공중합체임을 확인할 수 있었다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.159-160
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• 2006

We developed novel catalyst, PHENICS composed of the combination of a cyclopentadienyl group to perform a high catalytic activity and a bulky phenoxy group, which performs the production of high molecular weight polyolefin. The polymerization activity of PHENICS at high temperature is higher than well-known CGC catalyst. PHENICS showed the excellent ability of comonomer incorporation into polymer chain. The obtained copolymer had a high molecular weight. The PHENICS catalyst is also active to the copolymerization of ethylene and several vinyl comonomers such as styrene, norbornen, and conjugated dienes. We will discuss new cocatalysts for PHENICS to improve activity and the ability of molecular weight control.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2002년도 봄 학술발표회 논문집
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• pp.195-198
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• 2002

Poly(crown ether)s as a functional polymer materials have powerful and selective complexation properties with a large number of metal cations and have advantage of facility of their recovery and modification of their complexation properties in contrast to their monomeric analogues. Poly(crown ether)s having pendant macrocyclic groups can easily form 2:1-type crown ether ring-to-cation complexes with particular metal ions which are a little larger than the cavity of the crown ether ring. (omitted)

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.71-76
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• 2006

Porous polymer monolithic columns were prepared by the direct free radical copolymerization of methacrylic acid and ethylene glycol dimethacrylate within the confines of a chromatographic column in the presence of toluene-dodecanol as a porogenic solvent. The separation characteristics of the monolithic columns were tested by a homologous series of xanthine derivatives, theophylline and caffeine. The effects of the polymerization mixture composition and polymerization condition, mobile phase composition, flow rate and temperature on the retention times and separation efficiencies were investigated. The results showed that the selection of correct porogenic solvents and appropriate polymerization conditions are crucial for the preparation of the monolithic stationary phases. The separation efficiency was only extremely weakly dependent on flow rate and temperatures. Hydrogen-bonding interaction played an important role in the retention and separation. Compared with conventional particle columns, the monolithic column exhibited good stability, ease of regeneration, high separation efficiency and fast analysis.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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• pp.221-226
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• 2008

Hydroxy-terminated polyether의 새로운 합성방법인 양이온 개환 공중합에 의해서 Ethylene oxide와 Tetrahydrofuran을 공중합 하였다. 중합은 1,4-Butandiol 존재 하에 $BF_3$ THF를 촉매로 반응이 진행되어 잘 제어된 Polyetherdiol을 합성할 수 있었다. Polyurethane 반응은 Polyetherdiol과 경화제로써 I-PDI/N-100 혼합물을 사용하였고, 경화촉매로 TPB/MA 혼합물을 사용하여 합성하였다. 이렇게 합성된 Polyurethane은 현재 미국에서 시판중인 ATK HTPE를 이용한 Polyurethane과 기계적 특성과 경화 거동을 비교 분석하였다.

• Macromolecular Research
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• 제11권4호
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• pp.231-235
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• 2003

Phase behavior information is necessary for accomplishing homogeneous copolymerization to obtain high yield of copolymers and prevent a fouling problem. Cloud-point data to $160^{\circ}C$ and 1,450 bar are presented for five $C_6$ hydrocarbon solvents, normal hexane, 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane, with poly(ethylene-co-53 mol% norbornene) ($PEN_{53}$). The pressure-concentration isotherms measured for $PEN_{53}$/n-hexane have maximums that range between 5 and 12 wt% $PEN_{53}$. The cloud-point curves for $PEN_{53}$ all have negative slopes that decrease in pressure with temperatures. The single-phase region of $PEN_{53}$ in n-hexane is larger than the regions in 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane. The cloud-point curve of $PEN_{53}$ in 2,2-dimethyl butane is located at higher temperatures and pressures than the curve in 2,3-dimethyl butane due to the reduced dispersion interactions with and limited access of 2,2-dimethyl butane to the copolymer. Similar cloud-point behavior is observed for $PEN_{53}$ in 2-methyl pentane and 3-methyl pentane.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.417-421
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• 2005

Tetrahydrofuran(THF)과 Ethylene oxide(EO) 또는 EO를 단량체로 하는 양이온 개환중합을 이용한 새로운 두 가지의 합성기술로서 random 또는 tri-blcok HTPE(Hydroxyl-terminated polyether)를 합성할 수 있었다. 이들 반응은 $BF_3O(C_2H_5)_2$를 촉매로 하고 1,4-butanediol 또는 PTHF를 개시제로 하였다. 공중합체의 구조는 단량체의 함량비 또는 초기 PTHF와 EO의 첨가량에 의해 조절되며, 분자량의 조절은 촉매가 아닌 [단량체]/[디올]의 비로서 조절할 수 있었다. 실험결과 위 두 가지 random과 tri-block HTPE를 IPDI/N-100혼합 디이소시아네이트 경화제와 혼합하여 제조된 폴리우레탄에 적용하였으며, 추진제 바인더 제조를 위한 prepolymer로서 사용할 수 있었다.

• 폴리머
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• 제24권6호
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• pp.751-756
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• 2000

rac-Et(Ind)$_2$ZrC1$_2$/MMAO계를 사용한 에틸렌(E)과 시클로올레핀 (CO)의 공중합에서 CO의 구조가 촉매 활성 및 공중합체 (COC)의 구조와 성질 등에 미치는 영향을 조사하였다. 즉, 노르보르넨 (N), 페닐기 또는 비닐기가 치환된 형태인 5-페닐-2-노르보르넨 (PN) 및 5-비닐-2-노르보르넨 (VN)을 사용하여 [CO]/[E] 농도비에 따른 촉매 활성 및 공중합체의 성질을 조사하였다. [CO]/[E] 공급비가 증가함에 따라 COC에 대한 촉매 활성은 감소하였고, $T_{g}$ 는 증가하는 일반적인 경향을 보였으나, 그 변화 정도는 CO의 종류에 따라 달랐다. E와 VN의 공중합체 구조를 FT-IR과 $^{13}$C-NMR로 조사한 결과, VN에 존재하는 고리내의 C=C 이중결합이 중합에 관여하고 비닐기의 C=C 이중결합은 그대로 남아있는 것을 확인하였다. 그리고 공중합체 내에 존재하는 비닐기의 C=C 이중결합에 글리시딜메타크릴레이트를 graft하여 공중합체를 기능화하였다.

• Elastomers and Composites
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• 제24권2호
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• pp.110-121
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• 1989

The radical initiated graft copolymerization of acrylonitrile(AN) and 4-chlorostyrene(4-Clst) onto ethylene-propylene-diene terpolymer(EPDM) rubber was investigated under various conditions. Graft copolymer(AU-EPDM-4-Clst) was isolated b: selective solvent extraction and identified by using IR spectroscopy. The percent grafting is determined as a function of solvent, reaction time, and monomer mole ratio. Percent grafting decreased in the order of tetrahydrofuran(THF)>THF/ethyl acetate(EA)(1 : 1)>cyclohexane/EA(1 : 1)>n-hexane/EA(1 : 1). Grafting increased continuously with increasing the reaction time up to 40 hr, beyond which the grafting levelled off. It was observed that percent grafting increased as increasing [4-Clst]/[AN] mole ratio, but decreased when [4-Clst]/[AN] mole ratio was higher than 1.60. The light resistance of graft copolymer(AN-EPDM-4-Clst) was better than that of ABS.

• 한국재료학회지
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• 제33권1호
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• pp.1-7
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• 2023

The physical and antibacterial properties of ophthalmic lenses fabricated by copolymerization with hydrogel monomers using two types of graphene were measured, and their usability as contact lens materials was analyzed. For polymerization, silicone monomers, including SID-OH, 3-(methacryloxy)propyl tris(trimethylsiloxy)silane, and decamethylcyclopentasiloxane, were used, and N,N-dimethylacetamide, ethylene glycol dimethacrylate as a crosslinking agent, and azobisisobutyronitrile as an initiator were added. Also, graphene oxide nanoparticle (GON) and graphene nanoplate (GNP) were used as an additive, and the physical properties of the lenses fabricated after copolymerization were evaluated. The fabricated lenses satisfied the basic physical properties of general hydrogel contact lenses and showed the characteristics of lenses with high water content, and the disadvantage of very weak durability, due to low tensile strength. However, it was confirmed that the tensile strength and antibacterial properties were greatly improved by adding GON and GNP. With GON, the oxygen permeability and refractive index of the fabricated lenses were slightly improved. Therefore, it was determined that the graphene materials used in this study can be used in various ways as a contact lens material.