• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.99-100
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• 2006

Orthogonally protected block copolymers of based on p-hydroxystyrene were prepared with high control via nitroxy mediated radical polymerization using an alkoxyamine as an unimolecular initiator. Thin films of partially protected block copolymer were prepared by spin or dip coating. A well defined nanostructure could be observed as a result of phase separation e.g. cylinders in a matrix oriented perpendicular or parallel to the substrate. The nanostructure of the polymeric films can be defined by the block copolymer composition and it determines surface properties and allows further, selective functionalization, e.g. via click chemistry. The thin films can be designed in a way to allow a patterning based on a thermal or photochemical stimulus.

• 폴리머
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• 제24권2호
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• pp.268-275
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• 2000

고전기장을 이용하여 제조한 도전성 탄소섬유/폴리에틸렌 복합필름에 있어서 고분자 점착하층의 두께가 제조된 필름의 체적비저항과 인장강도에 미치는 효과에 대하여 연구하였다. 탄소섬유(CF) 함량과 CF 층밀도에 따라 제조된 필름의 체적비저항과 인장강도의 점착하층에 대한 의존성의 양상은 복잡하게 나타났다. 이는 점착하층의 증가에 따라서 필름 하층면에 중심부나 위쪽에 비하여 CF 농도가 낮은 절연성 고분자층의 두에가 증가하고 필름 상층면 근처에서는 CF의 함침에 필요한 고분자 매트릭스의 양이 적어져 매트릭스 함침이 불충분하여 기공이 포함된 구조를 형성시키는 효과와 증가된 매트릭스의 유동성을 바탕으로 CF 분산성이 향상되고 동시에 보다 치밀한 구조가 형성되는 두 가지 상반되는 효과의 상대적 기여 정도의 차이를 통하여 설명할 수 있었다. 이들 결과는 전자파 차폐용 고도전성 고분자 차폐필름의 제조에 있어서 전기적 성질과 기계적 성질의 최적화하는데 중요하다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.239-239
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• 2006

In the present study, we synthesized CBDA-FDA and its analogue, poly(4,4' -(9,9-fluorenyl)diphenylene pyromellitimide) (PMDA-FDA), and then investigated quantitatively the orientational distributions of the polymer chain segments in the surfaces of their films by using linearly polarized Fourier transform infrared (FTIR) spectroscopy and optical retardation analysis. We also examined the films' surface topographies using high spatial resolution atomic force microscopy (AFM). Further, rubbed films were used to assemble antiparallel and $90^{\circ}-twisted$ nematic (TN) LC cells, and the alignment behaviors, pretilt angles and anchoring energies of the LC molecules in the cells were determined. The films were found to have very interesting surface morphologies and LC alignment behaviors, which have not previously been reported. The observed LC alignments, pretilt angles and anchoring energies are discussed by taking into account the interactions of the LC molecules with the oriented polymer chain segments and the surface morphologies.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.161-161
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• 1999

In the field of material science, the interests and efforts to modify the surface of materials in agreement with the need of usage have been extensively increasing. he modification to improve the wettability of surface is very important is terms of adhesion, printing, etc. It is very difficult to modify metal surface into hydrophilic one. therefore, surfactant coating has been generally used in many cases. However, surfactant has disadvantages such as environmental problem, soluble in water. in this study, hydrophilic polymer films as alternative of surfactant were deposited on metal substrate by DC plasma polymerization. Hydrophilic polymer films deposited by DC plasma show many merits such as good wettability, stone adhesion to substrate, high resistance to most chemicals. Monomer gas and reactive gas were used as source plasma polymerization. Plasma polymerized films were fabricated with process parameters of deposition time, ratio of gas mixture, current, pressure, etc. Effects of these variables on wettability of plasma polymer films will be discussed. With XPS and FT-IR analyses of plasma polymeric films, the relation between wettability and chemical state of polymer films by DC plasma was investigated.

• Macromolecular Research
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• 제16권8호
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• pp.725-733
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• 2008

Polyimide (PI) multilayer thin films were prepared by spin-coating from a poly(amic acid) (PAA) and poly(amic acid) ammonium salt (PAAS). PI was prepared from pyromellitic dianhydride (PMDA) and 4,4'-oxydianiline (ODA) PAA. Different compositions of PAAS were prepared by incorporating triethylamine (TEA) into PMDA-ODA PAA in dimethylacetamide. PI multilayer thin films were spin-coated from PMDA-ODA PAA and PAAS. The PAAS comprising cationic and anionic moieties were spherical with a particle size of $20{\sim}40\;nm$. Some particles showed layers with ammonium salts, despite poor ordering. Too much salt obstructed the interaction between the polymer chains and caused phase separation. A small amount of salt did not affect the interactions of the interlayer structure but did interrupt the stacking between chains. Thermogravimetric analysis (TGA) showed that the average decomposition temperature of the thin films was $611^{\circ}C$. All the films showed almost single-step, thermal decomposition behavior. The nanostructure of the multilayer thin films was confirmed by X -ray reflectivity (XRR). The LF 43 film, which was prepared with a 4:3 molar ratio of PMDA and ODA, was comprised of uniformly spherical PAAS particles that influenced the nanostructure of the interlayer by increasing the interaction forces. This result was supported by the atomic force microscopy (AFM) data. It was concluded that the relationship between the uniformity of the PAAS particle shapes and the interaction between the layers affected the optical and thermal properties of PI layered films.

• 콘크리트학회논문집
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• 제15권6호
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• pp.888-893
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• 2003

본 연구는 폴리머 시멘트 모르타르 및 콘크리트에 오토클래이브양생을 적용하면 이들의 제성질은 폴리머의 종류에 크게 의존된다. 따라서 본 연구에서는 시멘트 혼화용 폴리머 디스퍼전으로 제작된 폴리머 필름의 오토클래이브양생을 실시하여 그 내구성을 기초물성 및 적외 흡수 스펙트럼의 변화로부터 검토하였다. 그 결과 오토클래이브양생에 의해서 SBR 필름은 성능이 저하되지 않았지만, EVA 및 PAE 필름은 상당히 성능이 저하되었으므로 오토크래이브 양생을 적용하는 경우, SBR 혼입 폴리머 시멘트 모르타르 및 콘크리트는 성능이 저하되지 않았지만, EVA 및 PAE 혼입 폴리머 시멘트 모르타르 및 콘크리트는 폴리머의 비누화에 의해서 뚜렷하게 성능이 저하된다고 판단된다.

• 폴리머
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• 제24권4호
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• pp.453-458
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• 2000

이미다졸-금속 이온 구조를 갖는 고분자 Langmuir-Blodgett (LB)막과 이들의 캐스트막을 다공성막 필터 위에 제조하여 산소와 질소의 투과성을 비교 검토하였다. 양친성 고분자 폴리 (N-(2-(4-이미다졸일)에틸)말레이미드-alt-1-옥타데센) (IM-O)은 폴리 (무수말레산-alt-1-옥타데센)과 히스타민의 반응으로 합성되었다. IM-O 단분자층은 철(III) 이온을 갖는 하층액 위에서 매우 안정하였다. LB막의 분자 구조는 FT-IR을 통하여 결정하였으며, LB막내에 존재하는 금속 이온의 농도는 XPS 측정으로 분석하였다. LB막의 균일성과 안정성을 SEM 관찰을 통하여 간접적으로 평가하였다. 본 LB막과 캐스트막의 기체 선택성은 산소보다 질소가 약간 높게 나타났으며, 두 기체에 대하여 모두 고투과성을 나타냈다.

• 한국포장학회지
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• 제5권1호
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• pp.37-46
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• 1999

Water vapor permeability of films is commonly calculated from the water vapor transmission rate of the film measured using a permeability cup method which is essentially a gravimetric method. This method was originally developed for petroleum based plastic films with low water vapor permeability. In the case of hydrophilic bio-polymer films, the resistance caused by a stagnant air layer, which is developed between the underside of the film mounted on the cup and the surface of the desiccant saturated salt solution or distilled water, can be significant and, if neglected, ran lead to underestimation of water vapor transmission rates. Therefore, it is necessary to correct water vapor transmission rate data to accurately estimate the water vapor permeability of bio-polymer films.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.201-201
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• 2006

In this study the glass transition temperature in thin polymer films has been studied. Ellipsometry has been used to measure $T_{g}$ of thin film as a function of film thickness. Empirical equation has been proposed to fit the measured $T_{g}$ pattern with thickness. Also, a continuous multilayer model was proposed and derived to describe the effect of surface on the observed $T_{g}$ reduction in thin films, and the depth-dependent $T_{g}$ profile was obtained. These results showed that $T_{g}$ at the top surface was much lower than the bulk $T_{g}$ and gradually approached the bulk $T_{g}$ with increasing distance from the edge of the film. The model and equation were modified to apply for the polymer coated on the strongly favorable substrate and the freely standing film.

• 마이크로전자및패키징학회지
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• 제7권2호
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• pp.37-42
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• 2000

저유전상수 폴리머와 $SiO_2$위에 형성된 Al/Ti박막의 우선방위에 대해 비교하였다. DC 마그네트론 스퍼터를 이용하여 50 nm 두께의 Ti과 500 nm의 Al-1%Si-0.5%Cu(wt%) 합금 박막을 저유전상수 폴리머와 $SiO_2$기판위에 증착하였다. Al의 우선방위는 XRD $\theta$-2$\theta$와 rocking curve로 측정하였고, Al/Ti박막의 미세조직은 투과전자현미경 (TEM)으로 관찰하였다. 저 유전상수 폴리머 위에 증착된 Al/Ti박막은 $SiO_2$위에 증착된 것보다 낮은 우선방위를 가졌다. 단면 TEM으로 Ti을 관찰한 결과, $SiO_2$위의 Ti의 결정립은 기판에 수직하게 성장하였으나 저유전상수 폴리머 위의 Ti 결정립은 등축정으로 성장하였으며, 저유전상수 폴리머위의 Al/Ti박막이 낮은 우선방위를 갖는 이유는 Ti 미세조직 때문이었다.