http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Bien Dong Che (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Bien Dong Che,Le-Thu T. Nguyen,Bao Quoc Nguyen,Ha Tran Nguyen,Thang Van Le,Nieu Huu Nguyen 한국고분자학회 2014 Macromolecular Research Vol.22 No.11
Radar absorbing materials (RAMs) for practical applications are expected not only to have strong microwaveabsorption and a wide absorption bandwidth, but also to be lightweight, to have a fine thickness and acceptablestructural performance, as well as being cost-effective. Although the dispersion of carbon-nanofillers in polymermatrices is a key factor determining the microwave absorbing properties of the composites, there have few studieson these effects. To our knowledge, to date, the realization of pristine multi-walled carbon nanotube (MWCNT)/polymercomposites as RAMs in industrial production has been restricted, due to high CNT contents or large composite thicknesses. Thus, in this work, two MWCNT dispersion processing methods, a solution process with surfactant-aid anda ball-milling dispersion, were investigated to fabricate pristine MWCNT/epoxy nanocomposites. The effects of thedifferent dispersion processes, CNT loading, and composite thickness on CNT dispersion in the matrix, were observedby TEM, and the electrical conductivity and X-band absorbing performance of the composites were assessed. Theuse of an ionic surfactant to aid the dispersion of CNTs in solution resulted in the best RAMs, with a good compromiseamong effective X-band absorption, small composite thickness, and very low CNT content. The ball-millingmethod also resulted in materials with a low CNT content and microwave absorbing performance acceptable forindustrial applications. Moreover, it offers a very simple and efficient route suitable for low-cost, mass productionof RAMs. The results showed that by facile approaches of dispersing pristine commercial MWCNTs in an epoxyresin matrix, composites of only 2-3 mm thickness and as little as 0.25-0.5 wt% CNT loading could be obtained,with a relatively wide X-band operating bandwidth and maximum absorptions exceeding 18-25 dB.
-
A Novel Conducting Amphiphilic Diblock Copolymer Containing Regioregular Poly(3-hexylthiophene)
Ha Tran Nguyen,Bien Che Dong,Nieu Huu Nguyen 한국고분자학회 2014 Macromolecular Research Vol.22 No.1
Amphiphilic rod-coil diblock copolymers combining the conductive features of a conjugated polymer andnanoscale morphologies arising from micro-phase separation of dissimilar blocks are attractive as potential materialsfor electronic applications. The synthesis and properties are reported for a novel amphiphilic diblock copolymer containinga block of regioregular poly(3-hexylthiophene) (P3HT) and poly(methyl methacrylate-random-2-hydroxyethylmethacrylate) (P(MMA-r-HEMA)) as the hydrophilic block. Well-defined rod-coil P3HT-b-P(MMA-r-HEMA)amphiphilic diblock copolymers with molar masses of around 11,000 and low molar mass dispersities (ÐM) below1.5 were successfully synthesized via the combination of quasi-living Grignard metathesis (GRIM) polymerizationand atom transfer radical polymerization (ATRP). P3HT was first obtained in a regioregular form with an averagemolecular weight of around 7,200 g/mol and ÐM below 1.3. Post-polymerization end-group modifications of the asobtainedP3HT were then successfully realized to give a macroinitiator for the ATRP of MMA and HEMA co-monomers,resulting in the P3HT-b-P(MMA-r-HEMA) diblock copolymers. The structure and properties of the resultingdiblock copolymers were characterized by proton nuclear magnetic resonance (1H NMR), gel permeation chromatography(GPC), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectroscopy and modulated differentialscanning calorimetry (MDSC).
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
