• Macromolecular Research
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• 제15권2호
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• pp.173-177
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• 2007

Living anionic and cationic polymerizations have been combined to prepare various types of comb-like copolymers composed of polystyrene (PS) and polyisoprene (PI) blocks, with a precisely controlled architecture. According to the relative placement of these elementary building blocks, combs with randomly distributed PS and PI or with poly(styrene-b-isoprene) diblock branches (I & II, respectively) can be prepared. The reaction procedure initially includes the synthesis of a poly(chloroethylvinyl ether) using living cationic polymerization, which is used as the reactive backbone to successively graft $PS^-Li^+$ and $PI^-Li^+$ or $PI-b-PS^-Li^+$ to obtain structures (I) or (II). The synthesis of Janus-type PS-comb-b-PI-combs (III) initially involves the synthesis of a diblock backbone using living cationic polymerization, which bears two distinct reactive functions having either a protected or activated form. Living $PS^-Li^+$ and $PI^-Li^+$ are then grafted, in two separate steps, onto each of the reactive functions of the backbone, respectively.

• 폴리머
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• 제25권4호
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• pp.602-607
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• 2001

이중 측쇄 이타코네이트 단위를 가지는 새로운 겔 전해질로 이용하기 위하여 bis(2-methoxyethyl)itaconate (bis(ME)I)를 itaconic acid와 2-methoxyethanol과 에스테르화 반응에 의하여 합성하였다. AN과 bis(ME)I의 공중합체들은 라디칼 중합에 의하여 AN/bis(ME)I = 9/1 ~ 1/1 조성을 가지는 것을 합성하였다. 최적의 기계적 성질과 이온전도도는 AN/bis(ME)I = 5/1 과 6/1 (25 ~ 35 wt%), LiClO$_4$(15 wt%) 그리고 가소제 (EC/PC=1/1) (40 ~ 50 wt%)에서 보여주었다. 가소화 겔 이온전도체는 질기고 안정된 기계적 성질을 보여주었으며 이온전도도는 8.12 ${\times}$ 10$_{-4}$ ~ 1.87 ${\times}$ 10$_{-3}$S/cm을 보여주었다. 최대 이온전도성을 보여주는 이온전도체는 전형적인 PEO를 중심으로 한 이온전도성 고분자보다 10배 이상 높은 이온전도성을 보여주었다.

• 멤브레인
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• 제18권2호
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• pp.132-137
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• 2008

폴리비닐리덴플로라이드(PVDF) 지지체 위에 빗살모양의 술폰화된 공중합체를 코팅하여 나노 분리막을 제조하였다. 빗살모양의 공중합체는 원자전달 라디칼 중합법(ATRP)에 의해 제조하였으며, 폴리비닐클로라이드의 주사슬과 폴리스티렌 술폰산(PSSA)의 곁사슬로 구성되어 있다. 핵자기 공명법($^1H$-NMR), FT-IR분광학 그리고 WAXS 분석법에 의해 공중합체가 성공적으로 합성되었음을 확인하였다 PVC-g-PSSA로 구성된 복합 나노 분리막은 PSSA의 함량이 증가함에 따라 플럭스와 배제율 모두 증가하였다. 이러한 성능 향상은 분리막의 술폰산의 함량의 증가로써 설명할 수 있다. PSSA가 71wt%첨가된 나노 복합막의 배제율은 $Na_2SO_4$ 88%, NaCl 33%을 나타내었고, 플럭스는 $Na_2SO_4$ 26, NaCl $34L/m^2 h$을 각각 나타내었다.

• Macromolecular Research
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• 제15권2호
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• pp.95-99
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• 2007

The most recent developments in two areas: (a) synthesis of inorganic particles with control over size and shape by polymer additives, and (b) synthesis of inorganic-polymer hybrid materials by bulk polymerization of blends of monomers with nanosized crystals are reviewed. The precipitations of inorganics, such as zinc oxide or calcium carbonate, in presence and under the control of bishydrophilic block or comb copolymers, are relevant to the field of Biomineralization. The application of surface modified latex particles, used as controlling agents, and the formation of hybrid crystals in which the latex is embedded in otherwise perfect crystals, are discussed. The formation of nano sized spheres of amorphous calcium carbonate, stabilized by surfactant-like polymers, is also discussed. Another method for the preparation of nanosized inorganic functional particles is the controlled pyrolysis of metal salt complexes of poly(acrylic acid), as demonstrated by the syntheses of lithium cobalt oxide and zinc/magnesium oxide. Bulk polymerization of methyl methacrylate blends, with for example, nanosized zinc oxide, revealed that the mechanisms of tree radical polymerization respond to the presence of these particles. The termination by radical-radical interaction and the gel effect are suppressed in favor of degenerative transfer, resulting in a polymer with enhanced thermal stability. The optical properties of the resulting polymer-particle blends are addressed based on the basic discussion of the miscibility of polymers and nanosized particles.