• Composites Research
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• 제34권6호
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• pp.434-439
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• 2021

그래핀과 폴리 아닐린은 기존의 무기물 기반 열전 소재의 단점을 극복하고 유연한 열전 소자에 응용할 수 있는 유기물 기반 열전 소재이다. 본 연구에서는 그래핀-폴리 아닐린 복합체를 합성하고 빛에 의해 유도되는 광열전 특성을 측정하였다. 그래핀-폴리 아닐린 복합체는 그래핀과 폴리 아닐린을 공유결합으로 연결하기 위해 산화 그래핀에 아민 작용기를 도입하였고 산화 그래핀을 다시 환원하여 환원된 산화 그래핀을 얻은 뒤 아닐린과 중합하여 그래핀-폴리 아닐린 복합체를 합성하였다. 최적의 광열전 효과를 기대하기 위해 아닐린의 함유량을 변화하여 그래핀-폴리 아닐린 복합체를 제조하였고, FT-IR과 라만 분석을 통하여 화학 구조와 조성을 확인하였다. 광전류와 광전압 특성은 외부 전기장이 없이 빛을 비대칭으로 조사하여 아닐린 함유량에 따른 전류와 전압을 분석하였다. 아닐린의 함량이 증가할수록 그래핀-폴리 아닐린 복합체의 광전류가 증가하는 전기 전도도와 같은 경향을 보였고 광전압은 빛에 의해 열에너지로 전환되어 나타나는 그래핀-폴리 아닐린 복합체의 온도변화와 관련 있음을 확인하였다.

• Carbon letters
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• 제14권1호
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• pp.51-54
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• 2013

In this study, polyaniline (PANI)/graphene nanosheet (GNS) composites were synthesized through chemical oxidation polymerization by changing the weight ratio of aniline monomers. To examine the morphological structure of the composites, scanning electron microscopy and transmission electron microscopy (TEM) were conducted. TEM results revealed that fibril-like PANI with a diameter of 50 nm was homogeneously coated on the surface of the GNS. The electrochemical properties of the composites were studied by cyclic voltammetry in 1 M $H_2SO_4$ electrolyte. Among the prepared samples, the PANI/GNS (having 40 wt% aniline content) showed the highest specific capacitance, 528 $Fg^{-1}$, at 10 $mVs^{-1}$. The improved performance was attributed to the GNS, which provides a large number of active sites and good electrical conductivity. The resulting composites are promising electrode materials for high capacitative supercapacitors.

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1097-1100
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• 2009

New types of conducting polyaniline-polymannuronate (PANI-PM) composites were synthesized by in situ deposition techniques in an aqueous media. By dissolving different weight percentage of polymannuronate (PM) (5, 10, 15, and 25%), the oxidative polymerization of aniline was carried out using ammonium per sulfate as an oxidant. The obtained composites were studied for their thermal stability and electrochemical behavior. The thermal stability of PANI-PM composites is lower than PANI, which supports a strong interaction between PANI and PM. However, the composites show an appreciable electrochemical behavior. Based on these observation the PANI-PM composites can be explored in different fields such as electric devices, sensors, functional coatings, etc.

• Korean Chemical Engineering Research
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• 제52권6호
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• pp.781-788
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• 2014

Polyaniline modified graphene oxide (PANI/GO) composites were synthesized by dilute polymerization technique and were characterized by Fourier transformed infrared spectroscopy (FTIR), Raman spectroscopy, and scanning electron microscopy (SEM). The characterization results indicated that polyaniline molecules were successfully grafted on GO surfaces. The application of PANI/GO composites to the adsorption of heavy metals from aqueous solutions was investigated under ambient conditions. The maximum adsorption capacities of Co(II), Ni(II), Pb(II) and U(VI) ions on PANI/GO composites calculated from Langmuir models are 22.28, 25.67, 65.40 and 1552.31 mg/g, respectively. The excellent adsorption capacity suggests that PANI/GO composites can be applied as a promising adsorbent in heavy metal pollution cleanup in environmental pollution management.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.449-452
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• 2012

A polyaniline-gold composite was prepared via the polymerization of aniline hydrochloride with or without water-soluble graphite oxide using auric acid as an oxidant. The reaction products were characterized using Xray photoelectron spectroscopy. The thermal stability and embedded crystallinity of the composites were also investigated using thermogravimetric and X-ray diffraction analyses. The electrical properties of the composites were examined using cyclic voltammetric measurements at room temperature and temperature-dependent DC conductivity within 300-500 K. Compared to pure graphene oxide and polyaniline-gold composite, the polyaniline-gold-graphene composite exhibited higher crystallinity and thermal stability, and higher current density response under equivalent conditions.

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.99-106
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• 2013

Polyaniline-yttrium trioxide (PAni-$Y_2O_3$) composites were synthesized by the in-situ polymerization of aniline in the presence of $Y_2O_3$ The composite formation and structural changes in these composites were investigated by X-ray diffraction (XRD), Fourier transform infra red spectroscopy (FTIR), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The direct current (DC) electrical conductivity of the order of $0.51{\times}10^{-2}\;S\;cm^{-1}-0.283\;S\;cm^{-1}$ in the temperature range 300 K-473 K indicates semiconducting behavior of the composites. Room temperature AC conductivity and dielectric response of the composites were studied in the frequency range of 10 Hz to 1 MHz. The variation of AC conductivity with frequency obeyed the power law, which decreased with increasing weight percentage (wt %) of $Y_2O_3$. Studies on dielectric properties shows the relaxation contribution coupled by electrode polarization effect. The dielectric constant and dielectric loss in these composites depend on the content of $Y_2O_3$ with a percolation threshold at 20 wt % of $Y_2O_3$ in PAni. Electromagnetic interference shielding effectiveness (EMI SE) of the composites in the frequency range 100 Hz to 2 GHz was in the practically useful range of -12.2 dB to -17.2 dB. The observed electrical and shielding properties were attributed to the interaction of $Y_2O_3$ particles with the PAni molecular chains.

• 공업화학
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• 제9권7호
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• pp.979-984
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• 1998

Nylon6,6를 matrix로 사용하여 전도성 고분자인 polyaniline(PANI)과의 전도성 복합체를 블렌딩 방법에 의하여 제조하였다. 블렌딩은 m-cresol를 용매로 사용하였으며 PANI는 camphorsulfonic acid(CSA) 혹은 dodecylbenzenesulfonic acid (DBSA)와 같은 알킬 벤젠 술폰산으로 양성화시켰다. 또한, 비상용성인 두 고분자간의 혼화성을 개선시키기 위하여 가소제를 첨가하여 상분리를 최대한 억제시켰다. 제조된 전도성 복합체에 대하여 양성화제의 유무에 따라 또는 PANI의 함량에 따라 전기전도도 및 몰포로지 등을 측정 분석하였다. PANI 착체의 함량이 증가할수록 전기전도도는 증가하였고, 알킬 사슬의 길이가 긴 DBSA로 양성화된 PANI(25wt%)과 가소화된 nylon6,6의 전도성 복합체의 전기전도도는 1.02 S/cm까지 향상되었다.

• 공업화학
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• 제10권2호
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• pp.287-292
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• 1999

Polycarbonate (PC)를 matrix로 사용하여 전도성 고분자인 polyaniline (PANI)과의 복합체를 블렌딩 방법에 의하여 제조하였다. 용매로는 chloroform을 사용하였으며 PANI는 전하수송을 가능하게 하고 유기용매에 잘 용해될 수 있도록 camphorsulfonic acid (CSA) 혹은 dodecylbenzenesulfonic acid (DBSA)와 같은 알킬 벤젠 술폰산으로 양성화시켰다. 또한, 전도성 복합체의 전기전도성은 압축성형이 아닌 solution casting법에 의하여 향상시켰다. 아울러 양성화제 유무, PANI의 함량 또는 온도에 따라 전기전도도, 몰포로지 및 인장강도 등을 측정 분석하였다. PANI 착체의 함량이 많을수록 전기전도도는 증가하였으며 알킬사슬이 긴 DBSA로 양성화된 25 wt % PANI 착체의 전도성 복합체의 전기전도도는 3.18 S/cm까지 향상되었다.

• Korean Membrane Journal
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• 제6권1호
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• pp.37-43
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• 2004

Comb-type graft hydrogels composed of alginate and poly(N-isopropylacrylamide) (PNIPAAm) were prepared to manifest rapid temperature and pH sensitivity. To appear the electro-sensitivity, the polyaniline, conducting polymer, was added into the matrix. The swelling kinetics and ratios were compared under the various compositions of polyaniline. The swelling behaviors revealed that conducting polymer/hydrogel composites could control the swelling ratio and kinetics. The addition of polyaniline in the matrix improved the thermal stability in comparison with that of the hydrogel without polyaniline. In temperature sensitivity, the adding the polyaniline into the matrix decreased the degree of change in the swelling ratio. The swelling ratios continuously increased with increasing pH values. The drug release rate from the hydrogel increased with the adding the polyaniline and the applying the direct voltage to the hydrogels.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.927-933
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• 2011

Conducting polyaniline-poly($\varepsilon$-caprolactone) polymer composites were synthesized via in situ deposition techniques. By dissolving different weight percentages of poly($\varepsilon$-caprolactone) (PCL) (10%, 20%, 30%, 40%, and 50%), the oxidative polymerization of aniline was achieved using ammonium persulfate as an oxidant. FTIR, UV-vis spectra, and X-ray diffraction studies support a strong interaction between polyaniline (PANI) and PCL. Structural morphology of the PANI-PCL polymer composites was studied using scanned electron microscopy (SEM) and transmittance electron microscopy (TEM), and thermal stability was analyzed by thermogravimetric analysis (TGA) technique. The temperature-dependent DC conductivity of PANI-PCL polymer composite films was studied in the range of 305-475 K, which revealed a semiconducting behavior in the transport properties of the polymer films. Conductivity increased with the increase of PCL in below critical level, however conductivity of the polymer film was decreased with increase of PCL concentration higher than the critical value.