• Title/Summary/Keyword: graft polymerization

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Use of Amphiphilic Graft Copolymer as Dispersant for Carbon Nanotubes (양친성 그래프트 공중합체의 탄소나노튜브 분산제로의 이용)

  • Jeon, Ha-Rim;Ahn, Sung-Hoon;Chi, Won-Seok;Kim, Jong-Hak
    • Polymer(Korea)
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    • v.35 no.6
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    • pp.615-618
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    • 2011
  • Carbon nanotubes (CNTs) draw attention as promising materials due to their excellent electrical and mechanical properties. However, the intrinsic strong interaction between CNTs presents a challenge to their use in various applications. Here, we present a facile method to disperse single-walled carbon nanotubes (SWCNTs) in a polar solution using a graft copolymer, poly(vinyl chloride)-graft-poly(oxyethylene methacrylate), PVC-g-POEM. The graft copolymer was synthesized via atom transfer radical polymerization (ATRP), as confirmed by gel permeation chromatography (GPC) and $^1H$ NMR spectroscopy. The SWCNTs were uniformly dispersed in a polar solvent such as dimethylsiloxane (DMSO) using PVC-g-POEM as a dispersant, due to interaction between CNT and the graft copolymer, as revealed by transmission electron microscopy (TEM) analysis. Upon removal of the solvent, free standing nanocomposite films with good homogeneity were obtained.

Preparation and Properties of Polyolefin Graft Polymer available as a Primer for Polyurethane Adhesive (I) Synthesis of polyolefins with cyclic acid anhydride by free radical graft polymerization

  • Ryu, Ki Jung;Kim, Min Jung;Min, Seong Kee;Lee, Won Kee;Park, Chan Young
    • Elastomers and Composites
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    • v.50 no.2
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    • pp.119-125
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    • 2015
  • Because of their low surface free energy and absence of polar groups at the surface, polyolefins are substrates whose wetting and adhesion are very difficult. Free radical grafting of monomers to backbone polymer is one of the most attractive ways for the chemical modification of polymers. Synthesis of graft copolymer through graft polymerizations of PE and/or PP with phthalic anhydride (PhAn) was made and FTIR spectra of the graft polymer were the examined. And also the effects of phthalic anhydride content on the grafting ratio, thermal properties and contact angle of the graft polymer were examined.

Studies on the Physical Properties of Vinyl Monomers Graft Polymerized Silk Fibre (비닐 단량체 그라프트 중합견의 물성에 관한 연구)

  • 이용우;송기언
    • Journal of Sericultural and Entomological Science
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    • v.27 no.1
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    • pp.47-50
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    • 1985
  • The physical properties of graft polymerized silk fibre were investigated with various vinyl monomers. 1. The graft polymerization of styrene and methyl methacrylate onto raw silk reduced the tenacity and elongation of raw silk due to fixation of sericin covering silk fibre in, but the styrene grafting was more effective for sericin fixation of raw silk than the methyl methacrylate one. 2. The water absorbability of glycidyl methacrylate grafted silk increased 14.6% greater than that of methyl methacrylate grafted silk at the same degree of grafting polymerization. 3. The degree of grafting polymerization was increased mostly with ethylene glycol methacrylate. The water absorbability of ethylene glycol methacrylate grafted silk was higher than that of glycidyl methacrylate or ethyl acrylate grafted silk. But the grafted silk fabric increased the fabric flexural rigidity which was negatively related with the favorability of fabric hand-touch, as compared with that of nongrafted silk fabric. 4. The evenness of graft polymerization could be improved by agitating the polymerization bath at the fixed interval by reducing the inter size deviation of grafted silk skein and the thickness deviation of grafted silk fabric.

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Methacrylamide graft polymerization on silk fibroin dyed with reactive dyestuffs (반응염색견(反應染色絹)의 Methacrylamide graft 중합(重合))

  • Rhee, In Jeon;Lee, Dong Soo
    • Current Research on Agriculture and Life Sciences
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    • v.12
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    • pp.83-95
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    • 1994
  • Fixation rate of reactive dyes on silk fibroin showed the same tendency to absorption rate. Fixation rate of Yellow 179 and Blue 71 was quite slow and Black 5, Blue 49, Blue 4, Blue 19 and Blue 21 was relatively fast. Weight increase by MAA graft polymerization onto filk fibroin was decreased, on the whole, according to the the increase of dye fixation, but weight increase of silk fibroin dyed with Blue 71 and Blue 21 was much higher than that of silk fibroin. And weight increase of silk fibroin dyed with Yellow 179 was similar to that of silk fibroin and in case of Blue 19, weight increase was about 12%, constantly. Weight increase of silk fibroin dyed with Blue 71 and Blue 21 was higher and the others were lower than of silk fibroin. And weight increase was diminished according as the dyeing temperature rises. The color was a little changed by MAA graft polymerization.

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Radiation-Induced Graft Copolymerization of Acrylic Acid onto Polyester

  • Chang, Hoon-Sean;Kong, Young-Kun;Lee, Chong-Kwang;Park, Jae-Ho
    • Nuclear Engineering and Technology
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    • v.9 no.2
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    • pp.65-74
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    • 1977
  • The radiation-induced graft polymerization of acrylic acid onto polyester fabric was investigated with accelerated electron beams as ratiation source at high dose rates. Homopolymerization was suppressed by addition of cations which is known as homopolymerization inhibitor, but this practical advantage was obtained at the expense of grafting efficiency. The rate of grafting (%/sec) was proportional to the 0.82th power of dose rates over the range from 1.6$\times$10$^{6}$ to 10$\times$10$^{6}$ rad/sec. The grafted polyester fabric showed considerable improvement in moisture regain and antistatic properties.

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Preparation and Evaluation of Chitin Derivatives and Their Utilization for Waste-water Treatement

  • Aly, Aly Sayed;Jeon, Byeong-Dae;Kim, Young-Jun;Park, Yun-Heum
    • Proceedings of the Korean Fiber Society Conference
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    • 1996.10a
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    • pp.53-58
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    • 1996
  • The Chitin Thiocarbonate-Fe(II)-H2O2 redox initiator system was investigated for the graft copolymerization of acrylonitrile(AN) and acrylic acid(AA) monomers onto chitin powder. The reactions with vinyl monomers onto chitin were carried out under various the graft copolymerization conditions to elucidate the polymerization behavior in terms of graft yield. Reactions of chitin-acrylonitrile graft copolymer with hydroxyl amine hydrochloride and those with sodium hydroxide were conducted in order to obtain chitin-(amidoxime-co-acrylonitrile) and chitin-(acrylate-co-acrylamide) graft copolymers, respectively. The reaction efficiency was observed to depend on the alkali concentration, time, temperature, and the reactant concentrations. The prepared chitin derivatives were evaluated to find potential applications for use in wastewater treatments for adsorption and desorption of heavy metal ions as well as acidic and basic dyes.

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Graft Polymerization of Acrylic Acid onto nylon 6

  • Park, Jae ho;Lee, Chong-Kwang
    • Nuclear Engineering and Technology
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    • v.8 no.3
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    • pp.159-168
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    • 1976
  • Acrylic acid has been grafted onto nylon fabric with ceric salts and ${\gamma}$-rays from Co-60 as initiators. The distribution of molecular weight of the grafted polyacrylic acid has been determined and it was found that the ratio of weight-average and number-average molecular weight was higher in room temp. than in low temp. (-184$^{\circ}C$). The weight-average molecular weight of the polyacrylic acid was calculated from viscosity measurements in sodium hydroxide solution. The factors affecting graft polymerization of acrylic acid onto nylon were examined. A possible mechanism that the oxidation of nylon probably takes place at the methylene group attached to nitrogen to give a free-radical was discussed.

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Preparation and Characterization of Acrylic Acid Grafted Polypropylene Nonwoven Fabric (아크릴산 그라프트 폴리프로필렌 부직포의 제조와 특성)

  • Kim, Sang-Yool;Na, Choon-Ki
    • Fashion & Textile Research Journal
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    • v.6 no.3
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    • pp.384-392
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    • 2004
  • The purpose of this study is in development of effective filter-type polymer adsorbent for removal of pollutants from wastewater by UV irradiation graft polymerization. Photografting of acrylic acid (AA) on polypropylene (PP) nonwoven fabric using benzophenone (BP) as a photosensitizer was investigated. Inhibition of homopolymerization was achieved by adding various concentrations of $FeSO_4{\cdot}7H_2O$, $CuSO_4{\cdot}5H_2O$ and Mohr's salt. As AA concentration was increased, the degree of grafting was increased as to a specific value and then decreased, and the effect of BP concentration showed the same tendency. It was also found that the degree of grafting increased with reaction time and reaction temperature. Addition of the polyfunctional monomers and $H_2SO_4$ to the grafting system accelerated the photografting. The melting temperature, molecular weight and breaking stress and breaking strain were decreased with the increase in the degree of grafting.

Electron Beam -Induced Graft Polymerization of Acrylic Acid on Polypropylene Nonwoven Fabrics(II) (전자빔 가속기를 이용한 폴리프로필렌섬유의 개질(II) - 전자빔의 흡수선량 및 중합조건이 그라프트 공중합에 치는 영향 -)

  • ;N.I. Shtanko
    • Textile Coloration and Finishing
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    • v.15 no.3
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    • pp.154-160
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    • 2003
  • Polypropylene nonwoven fabrics were grafted with acrylic acid by a preirradiation method by using electron beam accelerator. The effect of irradiation dose, storage time, concentration of acrylic acid, reaction temperature, reaction time and Mohr's salt concentration on the degree of grafting were investigated in detail. The grafted Polypropylene nonwoven fabrics were characterized using IR spectroscopy and SEM. The results showed that the degree of grafting increased with increasing absorbed dose and the Mohr's salt in the acrylic acid solution promoted grafting efficiency.