• 한국염색가공학회지
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• 제17권3호
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• pp.1-7
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• 2005

Cationic dyeable polyester(CDP) was produced through melt blending of cationic chips having $2mol\%$ of sodium salt of dimethyl ester of 5-sulfoisophthalic acid(DMS salt) and normal polyester chips in different proportions to obtain yarns having varying amount of comonomer in the fiber. The modified polyesters showed increased moisture regain, decreased viscosity, lower softening point and improved antistatic characteristics, according to the amount of modifier. In dyeing at $100^{\circ}C$ the dyeing rate of cationic dyes with CDP fiber increased slowly than that of disperse dyes. In dyeing at $120^{\circ}C$ cationic dyes reached to equilibrium at 30min and disperse dyes at 10min. Cationic dyes in dyeing of CDP fabric have a better wash fastness compared with disperse dyes, also rubbing fastness of cationic dyes is better than that of disperse dyes. The light fastness of CDP fabric for cationic and disperse dyes is not good. The fastness of 75d/36f CDP fabric is higher than 75d/72f fabric. Solvent wicking fastness of CDP with cationic dyes is better than that of disperse dyes.

• Macromolecular Research
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• 제10권2호
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• pp.115-121
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• 2002

Synthesis of polymers with controlled thermosensitive properties was carried out by conventional radical copolymerization of N-isopropylacrylamide (NIPAAm) with N-vinylpyrrolidone (NVP) taken as a hydrophilic comonomer. Lower activity of NVP rather than NIPAAm was revealed by gravimetric and $^1$H NMR analysis. Thermosensitive properties of the copolymers were investigated. It was found that aqueous solutions of the copolymers undergo thermo-induced phase transition and become opaque, precipitate or gel with heating. After formation of the gels their significant contraction was observed at storage. Swelling degree and amount of expelled water were measured in dependence on the copolymer composition, temperature and ionic strength of environment medium and concentration of the solution. It was determined that in collapsed state gels exhibit quite high water content. According to physico-chemical properties of the copolymers observed they could be suitable for biomedical application as an injectable implant material.

• Macromolecular Research
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• 제17권12호
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• pp.1003-1009
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• 2009

Copolymers of N-vinylpyrrolidone (NVP) comonomer with styrene (St), hydroxypropyl methacrylate (HPMA) and carboxyphenyl maleimide (CPMI) were synthesized by free radical polymerization using 2,2'-azobisisobutyronitrile (AIBN) initiator in 1,4-dioxane solvent. The copolymers formed were characterized by FTIR, $^1H$ NMR and $^{13}C$ NMR techniques and their thermal properties were studied by DSC and TGA. Copolymer composition was determined by $^1H$ NMR and/or by elemental analysis and monomer reactivity ratios (MRR) were estimated by the linear methods of Kelen-Tudos (K-T) and extended Kelen-Tudos (EK-T) and the non-linear approach. Copolymers of St and HPMA with NVP formed blocks of one of the monomer units, whereas alternating copolymers were obtained in CPMI-NVP, depending upon the side chain substitution. The MRR values are discussed in terms of monomer structural properties such as electronegativity and electron delocalization. The sequence distribution of monomers in the copolymers was studied by statistical method based on the average reactivity ratios obtained by EK-T method.

• 한국응용과학기술학회지
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• 제25권4호
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• pp.525-532
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• 2008

To prepare a solution type acrylic pressure-sensitive adhesive, quarter polymers were synthesized from butyl acrylate(BA), 2-ethylhexylacrylate(2-EHA) as a base monomer, methyl methacrylate(MMA) as a comonomer, each of methacrylic acid(MAA), acrylic acid(AA) as a functional monomer. Acrylic solution type pressure-sensitive adhesives(PSA's) of isocyanate derivative crosslinking PSA's were prepared by crosslinking of BEMM, BEMA with toluene-2,4-diisocyanate. The structure of adhesive was identified by FT-IR. The viscosity was measured by using Brookfield DV-III and molecular weight was measured by using gel permeation chromatography. The physical properties of polyethylene film coated with BEMMT, BEMAT were measured as a function of the concentration. As the result, BEMMT(0.6, 0.8), BEMAT(0.6) showed peel adhesion of $160{\sim}180\;g_f$/25 mm width and shear adhesion of more than 24 hours, and tackiness of $4/32{\sim}6/32$ which was relevant to commercial usage.

• 폴리머
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• 제26권2호
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• pp.253-259
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• 2002

본 연구는 내열성, 저광학손실 광도파로용 고분자재료를 합성하고 그 물성을 조사한 것이다. 열안정성을 높이고 광학손실을 줄이기 위한 pentafluorophenylmaleimide와 복굴절률을 낮추기 위한 두가지 methacrylate 유도체와 가교제 역할을 하는 glycidylmethacrylate를 삼원 공중합하여 광가교가 가능한 poly(maleimide-co-methacrylate)를 합성하였다. 합성된 고분자들은 높은 열안정성을 나타내었고, 열처리에 의해서 가교가 됨을 확인하였다. 고분자의 굴절율은 공중합 비율에 의해서 조절가능하였고, 1.45~l.49 범위의 고분자가 합성되었다. 복굴절은$6{ imes}10^{-4}$ ~ $1{ imes}10^{-4}$ 범위의 낮은 값을 나타내었다. 이 고분자와 광개시제를 사용하여 접촉 인쇄 방식에 의한 노광과 습식 현상을 통해 깨끗한 광도파로 패턴을 얻을 수 있었다.

• 폴리머
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• 제24권6호
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• pp.787-793
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• 2000

분자량과 methylacrylate 함량이 다른 아크릴로니트릴 공중합체의 dimethylformamide (DMF) 농후용액의 겔화 거동 및 임계 겔농도 (c＊)를 조사하였다. 중합체 종류에 관계없이 저온에서 장시간 방치할 경우 방치시간에 따라 점도가 급격히 증가하여 겔화가 진행됨을 알았으며, 중합체의 분자량이 클수록, 방치온도가 낮을수록 그리고 공중합체 중 아크릴로니트릴 성분비가 증가할수록 겔화 진행속도가 증가하였고, 임계 겔농도는 감소하였다. 동적 점탄성 실험에서 겔 용액으로부터 얻은 필름은 진 용액으로부터 얻은 필름과 달리 두 개의 유리전이 영역을 나타내었다. 이러한 결과는 겔화과정에서 atactic 중합체중 입체 규칙적인 block들간의 쌍극자-쌍극자 상호작용에 의한 ordered junction zone의 존재를 강하게 시사하였다.

• 폴리머
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• 제24권6호
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• pp.763-769
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• 2000

E-beam 전조사법을 이용하여 아크릴산과 스틸렌 단량체를 폴리프로필렌 섬유에 그라프트 반응시켜 PP-g-(AAc/Sty) 공중합체를 합성하고 술폰화 반응시켜 다관능성 섬유상 양이온 교환체를 합성하였다. 합성체의 그라프트율은 물과 메탄올 혼합비가 30 : 70 vol%인 혼합용매에서 아크릴산과 스틸렌, 단량체비가 30 : 70 vol%일 때 190%로 최대이었으며 혼합용매의 조성비가 일정할 때 아크릴산 단량체의 양이 증가할수록 그라프트율은 감소하였다. 또한 이온교환체의 이온교환용량은 4.6 meq/g이었으며, 술폰화 이온교환체와 아크릴산 이온교환체의 리튬이온에 대한 흡착량을 비교한 결과 본 연구에서 합성한 이온교환체의 흡착성이 우수한 것으로 나타났다.

• Journal of Information Display
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• 제5권4호
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• pp.12-17
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• 2004

A series of statistical random copolymers of dioctylfluorene (DOF) and 3,4-ethylenedioxythiophene (EDOT) were synthesized by Ni (0) mediated polymerization and their light-emitting properties were compared with poly (9,9-di-n-octylfluorene) (PDOF). The synthesized polymers were characterized using UV-vis spectroscopy, TGA, photoluminescence (PL) & electroluminescence (EL) spectroscopy and by conducting molecular weight studies. The resulting polymers were found to be thermally stable and readily soluble in organic solvents. The UV-visible absorption and PL emission spectra of the copolymers were gradually red-shifted as the fraction of EDOT in copolymers increased. Light-emitting devices were fabricated in an ITO (indium-tin oxide)/PEDOT/polymer/Ca/Al configuration. Interestingly, the EL spectra of these devices were similar to the PL spectra of the corresponding polymer film. However, the EL devices constructed from the copolymer showed more than 10 times higher efficiency level than the devices constructed from the PDOF homopolymer. This higher efficiency is possibly the result of better charge carrier balance in the copolymer systems due to the lower HOMO levels of the copolymers in comparison to that of PDOF homopolymer.

• Macromolecular Research
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• 제12권5호
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• pp.459-465
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• 2004

We have synthesized poly(l,4-cyclohexylenedimethylene terephthalate-co-hexamethylene terephthalate) [P(CT-co-HT)] random copolymers having various comonomer contents, from 0 to 100 mol% HT, by melt-condensation and have investigated their crystallization behavior by using differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). We observed that P(CT-co-HT)s exhibit clear melting and crystallization peaks in their DSC thermograms and sharp diffraction peaks in their WAXD patterns for all of their copolymer compositions as a result of cocrystallization of the CT and HT units, even though the copolymers are statistically random copolymers. When we plotted the melting and crystallization temperatures of P(CT-co-HT)s and the d-spacings of all the reflections against the copolymer composition, we observed a eutectic point at ca. 80 mol% HT, which suggests that a crystal transition occured from a PCT-type crystal to a PHT-type crystal. Both the DSC and WAXD results support the notion that P(CT-co-HT) copolymers undergo an isodimorphic cocrystallization.

• Elastomers and Composites
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• 제40권3호
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• pp.159-165
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• 2005

반응성 모노머인 글리시딜메타크릴레이트 (GMA)를 과산화제를 이용하여 저밀도폴리에틸렌(LDPE)에 그라프트 한 후 이를 이용하여 나일론-6와 반응블렌드를 동방향 이축압출기를 사용하여 실시하였다. GMA의 그라프트는 FT-IR을 이용하여 확인하였으며, GMA의 그라프트율은 반응온도, 과산화제의 농도, 공단량체로 사용된 스티렌의 농도가 증가함에 따라 증가함을 알 수 있었다. LDPE/나일론-6 반응블렌드 보다는 LDPE-g-GMA/나일론-6 블렌드의 인장강도 및 신율이 향상됨을 알 수 있었으며, 스티렌이 첨가된 경우 보다 향상된 값을 나타냄을 알 수 있었다. 반응물의 모폴로지는 SEM을 이용하여 측정하였다.