• Title/Summary/Keyword: in situ polymerization.

Search Result 169, Processing Time 0.039 seconds

Templated Formation of Silver Nanoparticles Using Amphiphilic Poly(epichlorohydrine-g-styrene) Film

  • Park, Jung-Tae;Koh, Joo-Hwan;Seo, Jin-Ah;Roh, Dong-Kyu;Kim, Jong-Hak
    • Macromolecular Research
    • /
    • v.17 no.5
    • /
    • pp.301-306
    • /
    • 2009
  • This work has demonstrated that a novel amphiphilic poly(epichlorohydrine)-graft-polystyrene (PECH-g-PS) copolymer at 34:66 wt% was synthesized via atom transfer radical polymerization (ATRP) of styrene using PECH as a macroinitiator. The structure of the graft copolymer was characterized by nuclear magnetic resonance ($^1H$ NMR) and FTIR spectroscopy, demonstrating that the "grafting from" method using ATRP was successful. The self-assembled graft copolymer was used as a template film for the in-situ growth of silver nanoparticles from $AgCF_3SO_3$ precursor under UV irradiation. The in situ formation of silver nanoparticles with 6-8 nm in average size in the solid state template film was confirmed by transmission electron microscopy (TEM), UV-visible spectroscopy and wide angle X-ray scattering (WAXS). Differential scanning calorimetry (DSC) also displayed the selective incorporation and the in situ formation of silver nanoparticles within the hydrophilic PECH domains, probably due to stronger interaction of the silvers with the ether oxygens of PECH backbone than that with hydrophobic PS side chains.

Preparation and characterization of melamine resin microcapsules by in-istu polymerization. (In-situ 중합법에 의한 마이크로캡슐의 제조 및 특성분석)

  • 백남중;박연흠;김영준
    • Proceedings of the Korean Fiber Society Conference
    • /
    • 2001.10a
    • /
    • pp.316-319
    • /
    • 2001
  • 기능성 섬유는 원하는 기능을 발휘할 수 있는 기능성 물질을 섬유 또는 직물상에 물리적 혹은 화학적으로 처리함으로써 제조할 수 있다. 그러나 이러한 기능성 물질들이 물리적 혹은 화학적으로 불안정하거나 섬유에 대한 친화력이 약할 경우에는 기능성 물질들의 내구성이 저하되는 문제점이 발생한다. 이러한 문제점을 마이크로캡슐을 이용한 가공기술로 극복하려는 노력이 있었다. (중략)

  • PDF

Multiwalled Carbon Nanotubes Functionalized with PS via Emulsion Polymerization

  • Park, In-Cheol;Park, Min;Kim, Jun-Kyung;Lee, Hyun-Jung;Lee, Moo-Sung
    • Macromolecular Research
    • /
    • v.15 no.6
    • /
    • pp.498-505
    • /
    • 2007
  • This study demonstrated the in-situ functionalization with polymers of multi-walled carbon nanotubes (MWNTs) via emulsion polymerization. Polystyrene-functionalized MWNTs were prepared in an aqueous solution containing styrene monomer, non-ionic surfactant and a cationic coupling agent ([2-(methacryloyloxy)ethyl]trime-thylammonium chloride (MATMAC)). This process produced an interesting morphology in which the MWNTs, consisting of bead-string shapes or MWNTs embedded in the beads, when polymer beads were sufficiently large, produced nanohybrid material. This morphology was attributed to the interaction between the cationic coupling agent and the nanotube surface which induced polymerization within the hemimicellar or hemicylindrical structures of surfactant micelles on the surface of the nanotubes. In a solution containing MATMAC alone without surfactant, carbon nanotubes (CNTs) were not well-dispersed, and in a solution containing only surfactant without MATMAC, polymeric beads were synthesized in isolation from CNTs and continued to exist separately. The incorporation of MATMAC and surfactant together enabled large amounts of CNTs (> 0.05 wt%) to be well-dispersed in water and very effectively encapsulated by polymer chains. This method could be applied to other well-dispersed CNT solutions containing amphiphilic molecules, regardless of the type (i.e., anionic, cationic or nonionic). In this way, the solubility and dispersion of nanotubes could be increased in a solvent or polymer matrix. By enhancing the interfacial adhesion, this method might also contribute to the improved dispersion of nanotubes in a polymer matrix and thus the creation of superior polymer nanocomposites.

Preparation of polyaniline/cyanoethyl resin blends

  • Kim, Tae-Kyun;Kim, Seong-Hun;Oh, Kyung-Wha
    • Proceedings of the Korean Fiber Society Conference
    • /
    • 2003.10a
    • /
    • pp.93-93
    • /
    • 2003
  • Electrically conducting polyaniline/cyanoethyl resin (PANI/Cyan) blends were prepared by in situ polymerization. The mechanical properties of the blend films increased with increasing cyanoethyl resin and the blend films have moderate conductivity.

  • PDF

Critical Syndiotacticity Required for In-Situ Fibrillation of Poly(vinyl Alcohol) during Saponification of Poly(vinyl Ester)

  • Lyoo, Won-Seok;John Blackwell
    • Proceedings of the Korean Fiber Society Conference
    • /
    • 1998.04a
    • /
    • pp.130-134
    • /
    • 1998
  • The physical properties of poly(vinyl alcohol) (PVA) are highly dependent on the degree of syndiotacticity, which is determined primarily by the choice of the vinyl ester monomer precursor. Efforts to produce more syndiotactic PVAs, as well to increase the molecular weight, have centered on the polymerization of vinyl trifluoroacetate,$^1$ vinyl trichloroacetate,$^2$ and vinyl pivalate (VPi).(omitted)

  • PDF

The Production of Microcapsules containing Fragrant material (방향물질을 함유한 마이크로캡슐 제조)

  • 김혜림;송화순
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.26 no.5
    • /
    • pp.684-690
    • /
    • 2002
  • The microcapsules containing fragrant material as functional compound were produced by in-situ polymerization. The prepolymer was made from urea-formaldehyde(UF) and melamine-formaldehyde(MF) as wall materials of microcapsules. The effects of wall material, dispersing agent and ratio of wall material to core material on the mean diameter variation were investigated. Thermal efficiency and release behavior of microcapsules were measured. The resultant UF and MF microcapsules are capable of preserving fragrant oil for long self-life.

Development of New Fibers Related Sensitivity and comfortability -Preparation of Melamine Microcapsules Containing Fragrant oil and the Their Application- (감성기능 섬유신소재의 개발(I) - 방향성 멜라민 마이크로캡슐의 제조와 응용 -)

  • Hong, Ki Jeong;Park, Soo Min
    • Textile Coloration and Finishing
    • /
    • v.8 no.5
    • /
    • pp.76-83
    • /
    • 1996
  • Fragrant microcapsules were prepared by in situ polymerization using urea-formaldehyde prepolymer. Lemon oil and migrin oil as susceptible materials were used. The diameter and distribution of the microcapsule were controlled by several factors, such as wall material, core material content, emulsion agent and stirring speed, respectively. Susceptible cotton fabrics with fragrant release functionality were successfully produced by using microcapsule containing fragrant materials.

  • PDF

Effect of Mixing Process on the Wear Properties of UHMWPE/Kaolin Composite (입자충전 초고분자량 폴리에틸렌의 마모특성 : 입자충전 방법의 효과)

  • Ki, Nam;Lee, Geon-Woong;Yoon, Ho-Gyu;Park, Hong-Jo;Kwak, Soon-Jong;Kim, Jun-Kyung;Park, Min
    • Polymer(Korea)
    • /
    • v.26 no.6
    • /
    • pp.803-811
    • /
    • 2002
  • In this study the wear behavior of ultra high molecular polyethylene (UHMWPE) filled with kaolin particles by different methods was investigated. UHMWPE/kaolin composites were prepared by two different methods: polymerization-filling and powder mixing. Particularly in a powder mixing method. Particle dispersion and wear property according to powder mining method were examined. It was found from wear test that filling of inorganic filler into UHMWPE by polymerization filling was more effective way than by powder mixing method in improving Wear resistance of UHMWPE. It was also confirmed that abrasive wear was dominant wear mechanism and particle dispersion in the composite as well as interface property was an important factor in controlling the wear behavior of the resulting composites.

Fabrication of CNT/MgCl2-Supported Ti-based Ziegler-Natta Catalysts for Trans-selective Polymerization of Isoprene

  • Cao, Lan;Zhang, Xiaojie;Wang, Xiaolei;Zong, Chengzhong;Kim, Jin Kuk
    • Elastomers and Composites
    • /
    • v.53 no.3
    • /
    • pp.158-167
    • /
    • 2018
  • In this study, in-situ trans-selective polymerization of isoprene was carried out using titanium-based Ziegler-Natta catalysts. The catalysts were prepared by high-energy ball milling. Individually Large-inner-diameter carbon nanotubes (CNTL), and hydroxylated carbon nanotubes (CNTOH), along with magnesium chloride ($MgCl_2$) were used as the carriers for the catalysts. The optimum ball-milling time for preparing the $CNT/MgCl_2/TiCl_4$ Ziegler-Natta catalysts was 4 h. The $CNTOH/MgCl_2/TiCl_4$ catalyst showed a higher efficiency than that of the $CNTL/MgCl_2/TiCl_4$ catalyst, based on the rate of polymerization. The effects of the CNT-filler type on the isoprene polymerization behaviors and polymer properties were investigated. The morphologies of the trans-1,4-polyisoprene (TPI)/CNT and TPI/CNTOH nanocomposites exhibited a tube-like shape, and the CNTL and CNTOH fillers were well dispersed in the TPI matrix. In addition, the thermal stability of TPI significantly increased upon the introduction of a small amount of both CNTL/CNTOH fillers (0.15 wt%), owing to the satisfactory dispersion of the CNTL/CNTOH in the TPI matrix.