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        검색결과 151

        121.
        2001.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        An ACR/HMMM film was prepared by blending high-solid ACR with curing agent, hexamethoxymethyl melamine (HMMM). An active curing reaction was observed at 170℃. The dynamic viscoelastic Tg of the final film increased with the static viscoelastic Tg of the film. The log damp value, which means a viscoelastic ratio, decreased with the increase in the curing temperature of the film. Physical properties of the films were within a suitable range for films, and by an accelerated weathering resistance test the films were proved weather resistible ones.
        4,300원
        122.
        2001.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Acrylic resin(ACR) was blended with a curing agent, hexamethoxymethylmela-mine(HMMM), in which blending ratio was 70:30. The curing behavior was examined using Rheovibron. Cross-linking reaction started at 170℃ in 2 min of reaction and curing was completed in 10 min. It was found that the extent of cross-linking increased with the content of acetoacetoxyethyl methacrylate monomer in the ACR.
        4,200원
        123.
        2001.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        고속도 공구강 기판에 반응성 스퍼터링법으로 증착된 HfN/Si3N4와 NbN/Si3N4다층박막의 기계적인 성질들을 막 증착 조건에 따라 평가하였다. HfN/Si3N4와 NbN/Si3N4 다층박막의 강도는 N2/Ar비가 0.4일 때가지 증가하다가 유량비가 증가함에 따라 더 이상 증가하지 않았다. 두 다층박막의 강도는 낮은 온도에서의 열처리에 의해서는 거의 변화가 업지만 800˚C 정도의 고온에서는 열처리에 의한 산화로 인하여 감소하였다. 낮은 온도에서의 열처리는 밀착성을 향상시키는 반면 고온에서의 열처리는 강도의 감소 이외에 밀착성이 감소하므로 바람직하지 못하다.
        4,000원
        124.
        2001.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Curing reaction was carried out with the acrylic resin (ACR) [n-butyl acrylate/atyrene/2-hydroxyethyl methacrylate/acetoacetoxyethyl methacrylate (AAEM)] synthesized before and a curing agent, hexamethoxymethylmelamine (HMMM). With rotational rheometer, the effect of catalysts on curing rate of acrylic resin/melamine was examined. Among the four catalysts used, p-toluene sulfonic acid showed the highest reactivity, and the optimum amount of catalyst was 0.5 phr. It was observed that in the ACR/HMMM curing reaction, gelation point was lowered with the increasing the amount of AAEM and HMMM in the ACR.
        4,000원
        125.
        2001.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Acrylic quarternary polymers were synthesized to prepare high-solid coatings. Acrylic resins were synthesized by the radical polymerization of n-butyl acrylate, methyl methacrylate, 2-hydroxyethyl methacrylate and acetoacetoxyethyl methacrylate. From the results of experiment on reaction condition to get high-solid acrylic resins with 70% solid content and viscosity of 1200cps, it was found that di-tert-amyl peroxide among the four types of initiators have lower viscosity and higher degree of conversion. The optinum initiator amount, chain transfer agent, reaction temperature and the dropping time were 5wt%, 4wt%, 150℃ and 5hrs, respectively.
        4,000원
        126.
        2000.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Two-component polyurethane flame-retardant coatings were prepared by blending trichloro aromatic modified polyesters(TCMPs) and polyisocyanate. TCMPs were synthesized by polycondensation of trichlorobenzoic acid(TCBA), a flame-retardant component, with adipic acid, 1,4-butanediol, and trimethylolpropane. The content of TCBA was varied in 10, 20, and 30 wt% for the reaction. These new flame-retardant coatings showed various properties comparable to other non-flame-retardant coatings. Moreover, we carried out the combustion test and the flammability test for our flame-retardant coatings. The results of vertical burning test for the coatings containing more than 20 wt% of TCBA were determined as 'no burn'. The results of flammability test for the coatings with 20 wt% and 30 wt% of TCBA contents indicated the limiting oxygen index(LOI) values of 25% and 28% respectively, which implied relatively good flame retardancy.
        4,000원
        127.
        2000.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To prepare an environmental friendly high-solid coatings an acrylic resin containing 80% of solid content was synthesized by addition polymerization of caprolactone acrylate, n-butyl acrylate, ethyl methacrylate, and 2-hydroxyethyl methacrylate. The conversion was 78~93% and the prepared resin's physical properties are as follows: viscosity, 212~3424cps: Mn 1740~2400. There was a trend that viscosity and molecular weight of the resin increased with Tg, but no direct proportionality was observed.
        4,000원
        128.
        2000.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Pyrophosphoric lactone modified polyester(PATT) that contains two phosphorous functional groups in one unit base resin structure was synthesized to prepare a non-toxic reactive flame retardant coatings. Then the PATT was cured at room temperature with isocyanate, Desmodur IL, to get a two-component polyurethane flame retardant coatings(PIPUC). Comparing the physical properties of the films of PIPUC with the film of non-flame retardant coatings, there was no degradation observed in physical properties by the introduction of a flame-retarding component into the resin. We found that the char lengths measured by 45˚Meckel burner method were 3.1~4.4cm and LOI values recorded 27~30%. These results indicate that the coatings prepared in this study is good flame retardant one. The surface structure of coatings investigated with SEM does not show any defects and phase separation.
        4,000원
        129.
        2000.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Y2SiO5:Ce 형광체를 In2O3, Al2O3 및 SiO2로 코팅한 후 전계 방출 디스플레이에 요구되는 음극선 발광 특성을 조사하였다. Al2O3 코팅으로 Y2SiO(sub)5:Ce 형광체의 발광 효율과 에이징 특성은 감소되었다. 한편 Al2O3코팅으로 형광체의 발광효율은 증가하였으나 발광스펙트럼과 색좌표는 일부 변화하였다. 그러나 Y2SiO5:Ce 청색 형과체의 발광 효율은 SiO2코팅으로 크게 증가하였으며, 또한 SiO2 코팅한 Y2SiO5:Ce 형광체의 에이징 특성은 코팅 전에 비하여 크게 향상되었다.
        4,000원
        131.
        2000.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Quater polymer(MBHA) containing two types of acrylic functional group, acetoacetoxyethyl methacrylate(AAM) and 2-hydroxyethyl acrylate was prepared. Then, the MBHA was blended with polyisocyanate type Desmodur IL as a curing agent. Thereafter the mixture was cured at room temperature to get high solid acrylic/polyisocyanate. The MBHA was synthesized at 150℃ for 6 hours typically, and the final conversion reached 87-88%. Lowering Tg and increasing AAM amount in the MBHA resulted in high value of conversion. There was no difference in conversion with the variations of OH values. From the results of physical property tests, MIHS coating was proved to be a good automotive top-coating material.
        4,000원
        132.
        1999.11 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 PbZr(sub)0.53Ti(sub)0.47O3(PZT) 박막을 복수 도포함에 따른 박막내의 응력을 온도의 함수로 실시간(in situ) 측정하였으며, 응력발생의 원인에 박막의 건조, 열분해(pyrolysis), 치밀화 및 결정화 현상과 연관시켜 설명하였다. 도포직후 단층박막에 생성된 55MPa의 인장응력은 가열됨에 따라 300˚C-350˚C에서 최대 145MPa로 증가하였으며, 박막내의 응력은 모든 온도구간에서 항상 인장응력을 나타내었더. 다층도포시 650˚C까지 열처리 주기를 완료한 층이 두꺼워질수록 새로 도포한 층의 영향은 점차 감소하였으며, 9층박막에 이르러서는 가열과 냉각에 따라 응력이 동일하게 변화하였다. 응력측정 결과 다층박막의 치밀화는 350˚C에서 시작되어 520˚C-550˚C 부근에서 완료되는 것으로 나타났으며 치밀화가 시작하는 온도는 미세경도 측정결과와 일치하였다. PbTiO3(PT)와 달리 PZT 다층박막은 Si 기판 위에서 perovskite로의 결정화가 일어나지 않았다.
        4,000원
        133.
        1999.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Oxide powders of were prepared by spray drying, plasma densification and fused+crushed processes. The oxide coating layers were made by plasma spray and characterized by microstructure, hardness, adhesion strength and relative density. The optimum spray distance for the high quality coatings by spraying dried powders was found to be 9cm. A small amount addition of powder significantly improved coating characteristics by lowering the melting point of powders. The hardness and relative density of coating layers of the plasma densified powders were comparable to fused and crushed powders, however, the adhesion strength was much higher in the former case.
        4,000원
        134.
        1999.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objectives of this study is to investigate the optimum reaction conditions and to identify the product formula in the synthesis of a silicone/acrylic resin that curing in moisture at room temperature. By the addition polymerization of monomers, n-butyl acrylate, methyl methacrylate, n-butyl methacrylate, and 3-methacryloxypropyltrimethoxysilane. a quarter polymer was obtained. Among various initiators investigated in this study, 2.2'-azobisisobutyronitrille was found to be the most suitable initiator. The optimum reaction conditions found in this study are 70 wt% of initial solvent amount, 120 minutes of dropping time, 3 times of initiator addition, 82~105℃ of reaction temperature, and 8 hrs of reaction time. Also, number average molecular weight of 11700~33100 and molecular weight distribution of 1.81~3.44 were obtained.
        4,000원
        135.
        1998.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Two-component polyurethane flame retardant coatings were prepared by blending phosphate-containing modified polyesters(PMPEs) and TDI-adduct. PMPEs were synthesized by polycondensation of dimethyl phenylphosphonate, a flame retardant component, with 1,4-butanediol, adipic acid, and trimethylolpropane. The content of dimethyl phenylphosphonate was varied 10, 15, and 20wt% for the reaction. Various physical properties of these new flame retardant coatings were comparable to non-flame retardant coatings. Coatings with 20wt% dimethyl phenylphosphonate did not burn during the vertical burning test.
        4,000원
        136.
        1998.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        플라즈마 용사법을이용하여 AISI 316 스테인레스 금속모재에 0.1mm 두께의 NiCrAlCoY2O3금속 결합층과 0.3mm 두께의 ZrO2(8wt%Y2O3) 세라믹층으로 구성된 이층 단열코팅층을 제조하였다. 코팅층의 미세조직, 금속결합층의 산화를 고찰하였으며, 900˚C에서 등은 시험과 열반복시험 후, 접합강도시험을 통하여 코팅층의 단사정 상은 열처리시간이 길어질수록 약간 증가하였다. 또한 비변태성 t'의 c/a는 용사상태에서 1.0099이였으며, 100시간 열처리 후에는 1.0115로 약간 증가하였다. 그리고 용사층의 접합강도는 열처리 시간이 길어질수록 감소하였다. 등온열처리 후에는 1.0115로 약간 증가하였다. 그리고 용사층 의 접합강도는 열처리 시간이 길어질수록 감소하였다. 등온열처리 후, 파괴는 주로 세라믹층에서 일어났으며, 반복 열처리되 시편에서는 10회 이후 대부분 금속결합층/세라믹층의 계면에서 일어났다.
        4,000원
        137.
        1998.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Two-packaged polyurethane coatings were prepared by blending benzoic acid lactone modified polyester polyol(BLMPs) and HDI-biuret. BLMPs were synthesized by polycondensation of benzoic acid, viscosity depression component, with 1,4-butanediol, adipic acid, and polycaprolactone polyol. Kinematic viscosity of BLMP was gradually decreased with increasing benzoic acid content in BLMP. The low viscosity of modified polyester has an advantage of making a high-solid content coatings. After the film was coated with the prepared polyurethane coatings and cured at room temperature, the various physical properties were measured. They showed good physical properties such as flexibility, impact resistance, cross hatch adhesion, yellowness index, and rust resistance. These advantages are the results of introducing polycaprolactone polyol.
        4,000원
        140.
        1996.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We have prepared diamine-benzoquinone polymer which was known to excellent water proofing, high adhesion strength and good anti-corrosive effect, and have investigate with the possibility of application as a high performance resin for coatings. First of all, the reactivity of diamine-benzoquinone has been described an example of polymer reaction with research trend. The polymer reaction was divided into the polymerization with several diamine-benzoquinone and urethane group. The synthetic resin was shown a high solubility. In case of polymer containing urethane, water absorption content, water proofing and mechanical properties were controlled with the content, water proofing and mechanical properties were controlled with the content of quinone. It was shown that an use of choice was a possible result for various coatings. Diamine-quinone polymer can be used as a new resin for coatings. In addition, the polymer containing a functional group was shown a useful applicability as a high performance resin.
        4,000원
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