On-Line Monitoring of Reaction Temperatures During Anionic Polymerization of Poly(styrene-b-methyl methacrylate) and Poly(styrene-b-2-vinyl pyridine) with a 1,1-Diphenylhexyl Lithium Initiator in THF

김정수,노시태,이정해,권정옥 한국고분자학회 2014 Macromolecular Research Vol.22 No.3

Poly(styrene-b-methyl methacrylate) and poly(styrene-b-2-vinyl pyridine) block copolymers with narrowmolecular weight distributions (1.05≤MWD≤1.17) were achieved via a pre-cooled monomer addition method usinga diphenyl hexyl lithium initiator in tetrahydrofuran under sequential isothermal conditions. The styrene block waspolymerized at -25 and -15 ℃, and the second block copolymerization of PS-b-PMMA and PS-b-P2VP was carriedout at -78 ℃. A module-type reactor system was constructed under an inert atmosphere, which could monitor thetemperature and torque during polymerization. Monomers for the second block were cooled and maintained atapproximately -30 ℃to control the exothermic reaction temperatures while being added to the reactor. The exothermicreaction temperature could be minimized (ΔTRMAX ≤+11 ℃) by the addition of the pre-cooled monomer.

수계 Cu 나노입자 잉크에서 Poly(styrene-co-maleic acid) 접착 증진제가 잉크 레올로지와 인쇄패턴의 접착력에 미치는 영향

조예진,서영희,정선호,최영민,김의덕,오석헌,류병환,Jo, Yejin,Seo, Yeong-Hui,Jeong, Sunho,Choi, Youngmin,Kim, Eui Duk,Oh, Seok Heon,Ryu, Beyong-Hwan 한국재료학회 2015 한국재료학회지 Vol.25 No.12

For a decade, solution-processed functional materials and various printing technologies have attracted increasingly the significant interest in realizing low-cost flexible electronics. In this study, Cu nanoparticles are synthesized via the chemical reduction of Cu ions under inert atmosphere. To prevent interparticle agglomeration and surface oxidation, oleic acid is incorporated as a surface capping molecule and hydrazine is used as a reducing agent. To endow water-compatibility, the surface of synthesized Cu nanoparticles is modified by a mixture of carboxyl-terminated anionic polyelectrolyte and polyoxylethylene oleylamine ether. For reducing the surface tension and the evaporation rate of aqueous Cu nanoparticle inks, the solvent composition of Cu nanoparticle ink is designed as DI water:2-methoxy ethanol:glycerol:ethylene glycol = 50:20:5:25 wt%. The effects of poly(styrene-co-maleic acid) as an adhesion promoter(AP) on rheology of aqueous Cu nanoparticle inks and adhesion of Cu pattern printed on polyimid films are investigated. The 40 wt% aqueous Cu nanoparticle inks with 0.5 wt% of Poly(styrene-co-maleic acid) show the "Newtonian flow" and has a low viscosity under $10mPa{\cdots}S$, which is applicable to inkjet printing. The Cu patterns with a linewidth of $50{\sim}60{\mu}m$ are successfully fabricated. With the addition of Poly(styrene-co-maleic acid), the adhesion of printed Cu patterns on polyimid films is superior to those of patterns prepared from Poly(styrene-co-maleic acid)-free inks. The resistivities of Cu films are measured to be $10{\sim}15{\mu}{\Omega}{\cdot}cm$ at annealing temperature of $300^{\circ}C$.

무효화 에멀젼 공중합법과 반응염법을 이용한 전기영동 고분자 컬러나노입자에 제조

전진아(Ji Na Chon),하재희(Jae Hee Ha),임민호(Min Ho Lim),권용구(Yong Ku Kwon) 한국고분자학회 2010 폴리머 Vol.34 No.6

무유화 에멀젼 공중합법을 이용하여 180-200 nm의 지름을 가지는 단분산성 폴리(스티렌/디비닐벤젠/비닐 아세테이틴) [poly(ST-co-DVB-co-VAc)] 고분자 나노입자를 합성하였으며. 제조된 단분산성 고분자 나노입자의 표면을 비누화반응을 통하여 개질하여 단분산성 폴리(스티렌/디비닐벤젠/비닐알코올) [polyl(ST-co-DVB-co-VA)] 나노입자를 제조하였다 합성된 입자를 반응염료와 반응시켜 적색과 청색 단분산성 폴리(스타렌/디비닐벤젠/비닐알코올 나노입자를 제조하였으며 입자의 형태, 분산성 빛 표면전하를 전자현미경, 시차열분석기, UV/Vis 흡광기 및 제타 전하 측정장치를 이용하여 규명하였다. Colored, electrophoretic polymer nanoparticles of poly (styrene-co-divinylbenzene-co-vinyl acetate) [Poly (St-co-DVB-co-VAc)] were prepared by emulsifier-free emulsion co-polymerization and reactive dyeing. The emulsifier-free emulsion polymerization of styrene, divinyl benzene and vinyl acetate was carried out at 70 ℃ for 20 hrs to obtain monodisperse polymer nanoparticles of poly (St-co-DVB-co-VAc) with an average diameter of 180~200 nm. These nanoparticles were transformed into poly (styrene-co-divinylbenzene-co-vinyl alcohol) [poly (St- co- DVB- co- VA)] nanoparticles through the saponification reaction. The poly(St-co-DVB-co-VA) nano-particles were treated with reactive dyes to obtain the colored. monodisperse electrophoretic nanoparticles. and their mor-phology and surface charge were characterized by scanning electron microscopy, differential scanning calorimetry, UV/Vis absorbance and zeta-potentiometry.

A Study on the Role of -SO₃ ^- Ions in the Dehydration Limit of Poly(styrene-co-styrenesulfonic acid) Membrane

( Kwang-hwan Ko ),( Joon-seop Kim ),( Chang Hoon Lee ) 한국고무학회 2017 엘라스토머 및 콤포지트 Vol.52 No.3

In this work, the effect of low-temperature dehydration of a poly(styrene-co-styrenesulfonic acid) (PSSA) membrane was investigated by differential scanning calorimetry, fourier transform infrared spectroscopy (FT-IR), electron magnetic resonancespectroscopy (EMR), and ¹H- and ¹³C solid-state nuclear magnetic resonance spectroscopy. These analyses were performed at room temperature for powdered PSSA specimens with and without dehydration and the following key observations were made. First, FT-IR analysis showed that low-temperature dehydration not only transformed the [SO₃ - ···H⁺] ionic pair in the non-hydrated PSSA to an SO₃H group, but also induced the formation of -C=C- double bonds in the dehydrated PSSA. Second, the -SO₃ · radical was unambiguously identified by EMR spectroscopy. Third, H-abstraction was detected by ¹H magic-angle spinning spectroscopy. Finally, an unexpected color shift from white for the non-hydrated PSSA to a yellowish brown for the dehydrated sample was observed. In order to explain these experimental results, it was proposed that the formation of the intermediate hydrogen (H˙) or hydroxyl radical (HO˙) species was initiated by the dehydration process. The sespecies attacked the SO₃H group and the tertiary proton at the α-carbon, resulting in the formation of -SO˙ radicals and -C=C- double bonds, which correlated with the color shift in the dehydrated PSSA sample. The semechanisms are useful for understanding the simultaneous loss of an aromatic ring and -SO- groups in the PSSA fuel cell membrane.

1가, 2가 양이온으로 중화되고 극성, 비극성 가소제로 블렌드한 Poly(styrene-co-methacrylate) 아이오노머의 동적 기계적 연구

모하메드 루크만,김준섭 조선대학교 생산기술연구소 2007 生産技術硏究 Vol.29 No.2

Na^(+) 그리고 Ba^(2+) 양이온으로 중화된 poly(styrene-co-methacrylate) 아이오노머의 동적·기계적 성질에 dioctyl phthalate(DOP)와 glycerol(Glyc)가 어떠한 영향을 미치는지에 대해 동적 계계적 분석장치(DMA)를 사용하여 연구하였다. DOP가 첨가된 아이오노모의 matrix유리전이온도(T_(g))는 급격한 감소를 보이는 반면, Glyc가 혼합된 아이오노머의 경우에는 약간의 감소만을 보였다. 또한 이온 모듈러스와 cluster T_(g)의 급격한 감소가 관찰되었다. Glyc가 혼합된 PSMA 아이오노머에서 Ba^(2+)로 중화한 것과 Na^(+)로 중화한 것을 비교해 보면, 이온 모듈러스는 Ba^(2+)로 중화한 시료의 경우에 Na^(+)로 중화한 이이오노머에 비해 더 적게 감소하였다. DOP가 혼합된 PSMA 아이오노머도 같은 결과를 보여 주었다. 따라서 유리전이온도(T_(g))와 이온 모듈러스를 감소시키는 가소제 효과는 1가 양이온으로 중화한 것 보다 2가 양이온으로 중화한 것이 더 적다고 가정할 수 있다. The effects of the dioctyl phthalate (DOP) and glycerol (Glyc) on the dynamic mechanical properties of the poly(styrene co methacrylate) ionomers neutralized with Na^(+) and Ba^(2+) cations were studied using dynamic mechanical analyzer (DMA). The drastic decrease in the matrix glass transition temperatures (Tgs) by the addition of DOP but only a slight decrease by the incorporation of Glyc was observed in both systems. A significant decrease in the ionic modulus and cluster Tgs of both systems was also observed. The decrease in the ionic modulus of Ba^(2+) system was lower than that of the Na^(+) system at comparable amount of the Glyc, while similar level of decrease in ionic modulus was shown with DOP in both systems. Thus, it was suggested that the effects of the plasticizers in decreasing the Tgs and ionic modulus were less pronounced in the systems neutralized with di valent cation than that in mono valent one.

Dispersion Polymerization of Styrene Employing Lyophilic Comonomer in the Absence of Stabilizer: Synthesis of Impurity-free Microspheres

Han, Hye-Kyung,Lee, Jeong-Woo,Hong, Jin-Ho,Shim, Sang-Eun The Polymer Society of Korea 2009 Macromolecular Research Vol.17 No.7

We investigated the feasibility of dispersion polymerization without any stabilizer, which has been considered essential for ensuring colloidal stability. By employing small amounts of a lyophilic comonomer, 4-vinyl pyridine, styrene was successfully polymerized by dispersion polymerization in aqueous alcohol without stabilizer to afford stable poly(styrene-co-4-vinyl pyridine) copolymer microspheres. The stable microspheres were produced in the 4-vinyl pyridine range of 2-15 wt% to styrene. Without 4-vinyl pyridine, severely coagulated particles were obtained, implying that the poly(4-vinyl pyridine) moiety endowed colloidal stability. The polymerization kinetics, behavior, and properties of the ultimate particles showed general features of dispersion polymerization. The study results suggest that stabilizer- tree dispersion polymerization is possible, thereby facilitating the synthesis of impurity(stabilizer)-tree polymer particles.

Dispersion Polymerization of Styrene Employing Lyophilic Comonomer in the Absence of Stabilizer: Synthesis of Impurity-free Microspheres

한혜경,이정우,홍진호,심상은 한국고분자학회 2009 Macromolecular Research Vol.17 No.7

We investigated the feasibility of dispersion polymerization without any stabilizer, which has been considered essential for ensuring colloidal stability. By employing small amounts of a lyophilic comonomer, 4-vinyl pyridine, styrene was successfully polymerized by dispersion polymerization in aqueous alcohol without stabilizer to afford stable poly(styrene-co-4-vinyl pyridine) copolymer microspheres. The stable microspheres were produced in the 4-vinyl pyridine range of 2-15 wt% to styrene. Without 4-vinyl pyridine, severely coagulated particles were obtained, implying that the poly(4-vinyl pyridine) moiety endowed colloidal stability. The polymerization kinetics, behavior, and properties of the ultimate particles showed general features of dispersion polymerization. The study results suggest that stabilizer-free dispersion polymerization is possible, thereby facilitating the synthesis of impurity (stabilizer)-free polymer particles.

Poly(styrene-co-vinylbenzophenone) as photoactive antimicrobial and selfdecontaminating materials

Hong, Kyung Hwa,Sun, Gang Wiley Subscription Services, Inc., A Wiley Company 2008 Journal of applied polymer science Vol.109 No.5

<P>Photoactive structures such as benzophenone chromophoric groups were incorporated onto polymers by using a Friedel-Crafts acylation reaction. The structures and properties of the resultant polymers, poly (styrene-co-vinylbenzophenone) were evaluated as the ratio of benzoyl chloride to phenyl groups in polystyrene in the acylation bath increased. The results proved that the poly (styrene-co-vinylbenzophenone) in different contents of benzophenone groups was successfully prepared, and the contents of the benzophenone chromophoric group branched in the resultant polymer increased as the amount of benzoyl chloride in acylation bath increased. Also, the poly (styrene-co-vinylbenzophenone) copolymers revealed superior special activities such as antibacterial ability. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008</P>

Poly(butylene terephthalate)와 acrylonitrile butadiene styrene mixture에서 styrene계 copolymer가 용융 거동 및 물성에 미치는 영향: 열적 및 유변학적 성질

최규성 ( Kyu Sung Choi ),김용성 ( Yong Seong Kim ) 경남대학교 기초과학연구소 2010 기초과학지 Vol.27 No.-

본 연구에서는 결정성 고분자인 PBT와 비결정성 고분자인 ABS의 혼합물 제조에 있어서 스티렌계 탄성체가 열적 성질, 용융 상태에서의 유동 거동에 미치는 영향에 대해 조사하였다. PBT/ABS 혼합 시스템에서 PBT의 용융 온도와 결정화 온도는 조성에 무관하게 일정한 값을 나타내었다. ABS의 유리 전이 온도는 PBT의 조성이 증가함에 따라 직선적으로 증가하였으며, 열분해 온도는 열안정성이 우수한 PBT를 혼합함으로서 개선되었다. PBT/SEBS/ABS 혼합체의 복합 점도는 SEBS의 함량이 증가할수록 상승하였고, 증가하는 정도는 스티렌의 함량이 많은 SEBS-2를 사용한 경우가 SEBS-1을 사용한 경우보다 더 크게 나타났다. 용융 상태에서의 PBT/SEBS/ABS 혼합체의 G′과 G″은, SEBS-1을 사용한 경우에는 조성에 무관하였으나, SEBS-2를 사용한 경우에는 조성에 큰 영향을 받았다. In this study, thermal and rheological behavior has been investigated for the mixture of poly(butylene terephthalate) and acrylonitrile butadiene styrene. It turned out that melting and crystalization temperatures for PBT/ABS blends were kept similar although styrene composition varied. Glassy transition temperature of ABS increased as the amount of PBT increased and thermal decomposition of ABS became better by the addition of PBT. Viscosity of PBT/SEBS/ABS blends enhanced more with SEBS-2 than with SEBS-1. Also, G′ and G″ were more affected with SEBS-2 than with SEBS-1.

Study of optimized action properties with Polyethyleneimine (PEI) and various Poly(styrene-alt-maleic anhydride) (PSMA)

박재중,황기섭,이준영 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0

We successfully synthesized Poly(styrene-co-maleic anhydride) (PSMA) by using the co-polymerization system of styrene and maleic anhydride monomer. Then, PSMA-PEI copolymer was synthesized by reaction between PSMA copolymer and NH2 bond of Polyetyleneimine (PEI). The molecular weight is changed by controlling the amount of styrene, maleic anhydride and PEI was analyzed by GPC. PSMA-PEI copolymer was characterized by using FT-IR and 1H-NMR spectra. Also, the thermal property of PSMA-PEI copolymer was confirmed by DSC and TGA analysis.