• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1992년도 제2차 학술발표초록집
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• pp.94-94
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• 1992

• 대한전기학회논문지
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• 제45권3호
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• pp.438-443
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• 1996

The effect of plasma polymerization conditions on the structure of the plasma polymerized styrene were investigated by using Fourier Transform Infrared Ray(FT-IR), Differential Scanning Calorimetry (DSC), Gel Permeation Chromatography(GPC). Plasma polymerized thin film was prepared using an interelectrode inductively coupled gas-flow-type reactor. We show that polymerization parameters of thin film affect sensitivity and etching resistance of plasma polymerized styrene is 1.41~3.93, and deposition rate of that are 32~383[.angs./min] with discharge power. Swelling and etching resistance becomes more improved with increasing discharge power during plasma polymerization. (author). 11 refs., 10 figs., 1 tab.

• 한국잠사곤충학회지
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• 제34권2호
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• pp.32-40
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• 1992

반응개시제로 potassium persulfate를 사용한 MAA 가공견섬유에 대하여 열분석, IR spectrum, 아미노산 분석, 전자현미경 등의 기기분석을 통하여 반응 mechanism에 대하여 구명하고자 하였다. IR spectroscopy 분석에서 가공견섬유의 peak은 미가공견섬유와 MAA polymer의 peak을 모두 가지고 있으며, 특이한 peak의 변화는 관찰할 수 없었다. 아미노산 분석에서는 vinyl monomer가 graft된다는 종래의 특정 아미노산의 함량에 있어서, 가공률의 증가에 따른 변화를 관찰할 수 없었으며, MAA 가공견섬유의 중합 mechanism은 styrene 및 MMA의 graft 가공에서와는 일치하지 않는 것으로 나타났는데, 이는 monomer, 개시제, 반응조건에 따라 반응에 관여하는 아미노산이 다른 것으로 추정된다. SEM 관찰에서는 가공률이 낮은 경우의 섬유표면은 미가공견섬유의 표면과 그 차이를 인정할 수 없었으나, 가공률이 증가함에 따라 섬유표면에 섬유축방향으로 줄무늬가 형성되는 것을 관찰할 수 있었다. 이상의 관찰과 앞서 발표한 열분석 결과를 종합하면, potassium persulfate를 반응개시제로한 MAA 가공견의 중합기구에 대해서는 DSC나 IR spectroscopy에 의한 관찰로는 중합기구를 정성정량적으로 분석하기는 힘든 것으로 나타났으며, 아미노산 분석결과로부터 이미 styrene이나 MMA 가공견의 grafting site로 알려 져 있는 Gly, Ala, Ser, Tyr, Thr, Met 및 염기성 아미노산 등의 특정 아미노산에 선택적으로 graft되는 경향을 인정할 수 없으므로 이는 graft 중합에 의해 결합되는 것이라기보다 단지 섬유내부중합에 의해 polymer가 섬유내부에 형성되는 것으로 추정된다. 현미경관찰에서도 polymer는 주로 섬유내에 형성되며, 무게증가율이 큰 경우에는 섬유의 표면에 MAA에 의한 특징적인 줄무늬의 형성을 관찰할 수 있었다.

• 공업화학
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• 제16권3호
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• pp.397-402
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• 2005

Core-shell 형의 Poly(styrene-co-N-isopropylacrylamide) (poly(St-co-NIPAm)) 마이크로겔은 과항상칼륨(KPS)을 개시제로 사용하여 styrene (St)과 N-isopropylacrylamide (NIPAm)의 무유화 유화중합으로 제조하였다. St/NIPAm의 비, 모노머의 농도, 가교제의 농도에 따른 입자크기의 영향을 조사하였으며 고분자 마이크로겔의 온도에 따른 열감응성을 조사하였다. 마이크로겔의 입자 크기는 NIPAm의 몰비에 따라 증가하였으며 마이크로겔 분산용액의 투과도가 하한임계온도 이상($32{\sim}34^{\circ}C$)에서는 급격히 감소였다. 수용액 중에서 마이크로겔의 팽윤성은 모노머인 NIPAm의 농도가 증가할수록 증가하였으며 가교제의 농도에 따라서 감소하였다.

• Korean Chemical Engineering Research
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• 제50권6호
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• pp.1076-1081
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• 2012

라텍스 개질 콘크리트의 혼화용 라텍스를 개발할 목적으로 carboxylated styrene butadiene 라텍스를 이단계 유화중합법으로 제조하고 콘크리트에 적용하는 실험을 수행하였다. 음이온 유화제로는 sodium dodecylbenzene sulfonate와 sodium salt of lauryl sulfate를 선정하였고, 라텍스 안정제로는 nonylphenoxy poly(ethyleneoxy) ethanol 계열의 동족체들(n=10, 20, 40)을, 그리고 potassium persulfate와 sodium bisulfite를 redox 개시제로, $Na_2HPO_4$와 $K_2CO_3$를 전해질로 각각 사용하였다. 중합안정성에 대한 음이온 유화제의 종류와 사용량의 영향 및 입자크기의 전해질 농도 의존성을 실험적으로 고찰하여 LMC용 라텍스 제조에 적합한 중합처방을 제시하였다. 이 중합처방으로 제조한 라텍스의 LMC 용도에 대한 적용성을 시험한 결과, 슬럼프와 공기량은 한국도로공사의 품질기준을 충족하며, 역학적 물성시험 결과에서는 28일간 경화시킨 시편의 압축강도와 휨강도가 품질기준보다 각각 39.6, 87.3% 더 높은 증진효과가 발현됨을 확인하였다.

• Macromolecular Research
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• 제9권3호
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• pp.150-156
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• 2001

Polystyrenes(PS) were grafted onto polypropylene(PP) in the PP solution by ultrasonic irradiation-initiated polymerization of styrene. The resulting products consisted of mixtures of homopolymers and PP-PS copolymer because of the homopolymerization of styrene itself and copolymerization with PP. The dependency of the designated polymerization on sonication times was investigated to monitor the evolution lion of the copolymerization. Formation of the PP-PS copolymer was confirmed by FTIR analysis of the reaction products after a proper separation procedure of free PS and PP-PS copolymer. It was found that the tendency for the formation of PP-PS copolymer was closely related with the phase behavior of the PP/styrene mixture which was also influenced by sonication time. In order to verify the effectiveness of the PP-PS copolymer as a compatibilizer for PP/PS blend, melt mixing of PP/PS/PP-PS was performed in a batch mixer. During the mixing, the average torque was higher for the blend containing PP-PS copolymer influencing compatibilization. In accordance with the results from FRIR analysis and torque measurement, the PS domain size remarkably decreased in the PP/PS/PP-PS blend.

• Macromolecular Research
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• 제15권4호
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• pp.324-329
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• 2007

An octa-functional alkoxyamine initiator, with the 2,2,6,6-tetramethyl-l-piperidinyloxy (TEMPO) free radical, was synthesized based on resorcinarene, with its efficiency to initiate the nitroxide-mediated free radical copolymerization of styrene and methyl methacrylate (MMA) described. A difunctional analogue of this initiator was also synthesized, using resorcinol as the core molecule. The structures of the resulting initiators were confirmed by homolysis studies based on electron spin resonance spectroscopy and molecular modeling. The polymerization behavior and characteristics of the polymers obtained using these two initiators were also compared. Well-defined star-shaped and linear random copolymers, with low polydispersities and controlled molecular weights, were prepared. The efficiencies of these initiators towards copolymerization, as well as the parameters permitting the formation of well-defined polymers, were also investigated. The reactivity ratios were $r_a=0.42(a=styrene)\;and\;r_b=0.33(b=MMA)$ for the octa-functional initiator system and $r_a=0.45\;and\;r_b=0.39$ for the difunctional initiator system.

• Macromolecular Research
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• 제17권8호
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• pp.557-562
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• 2009

The free radical polymerization of styrene was initiated with azobis(isobutyronitrile) in the presence of benzene sulfonyl chloride. Analysis of the terminal structures of the obtained polystyrene with $^1H$ NMR spectroscopy revealed the presence of a phenyl sulfonyl group at the ${\alpha}$-end and a chlorine atom at the ${\omega}$-end of each polystyrene chain. The terminal chlorine atom in the polystyrene chains was further confirmed through atom transfer radical polymerization (ATRP) of styrene and methyl acrylate using the obtained polystyrenes as macroinitiators and CuCl/2,2'-bipyridine as the catalyst system. GPC traces of the products obtained in ATRP at different reaction times were clearly shifted to higher molecular weight direction, indicating that nearly all the macroinitiator chains initiated ATRP of the second monomers. In addition, the number-average molecular weights of the polystyrenes increased directly proportional to the monomer conversions, and agreed well with the theoretical ones.

• Transactions on Electrical and Electronic Materials
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• 제16권2호
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• pp.95-98
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• 2015

Organic polymer dielectric thin films of styrene and vinyl acetate were prepared by the plasma polymerization deposition technique and applied for the fabrication of an organic thin film transistor device. The structural properties of the plasma polymerized thin films were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, atomic force microscopy, and contact angle measurement. Investigation of the electrical properties of the plasma polymerized thin films was carried out by capacitance-voltage and current-voltage measurements. The organic thin film transistor device with gate dielectric of the plasma polymerized thin film revealed a low operation voltage of −10V and a low threshold voltage of −3V. It was confirmed that plasma polymerized thin films of styrene and vinyl acetate could be applied to functional organic thin film transistor devices as the gate dielectric.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.240-248
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• 2010

The blending effects of surfactants on the polystyrene emulsion polymerization were studied. The blending of Triton X-100 and SDS affects to the interfacial properties of the styrene monomer and water phases, and finally, the properties of the polystyrene latex particles. As the blending ratio of SDS/Triton X-100 increases, the interfacial tension and CMC of the blended surfactants were decreased and results in a reducing the size of the latex particles. It was found that the interfacial tension was reduced when the surfactant were blended. By increasing the SDS content, the interfacial tension was reduced, and, at a certain condition, the interfacial tension was reached to an extremely low value to form micro-emulsion and the nano-sized latex particles (80~110 nm).