• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.392.2-392.2
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• 2014

Poly (vinylidene fluoride) thin films were deposited by a spray-coating technology. Two organic solvents with different boiling point were used to prepare the mixture solution for spray coating process: N-Methylpyrrolodone ($B.P.=202^{\circ}C$); Tetrahydrofuran ($B.P.=66^{\circ}C$). Post-deposition annealing temperature was varied for the spray-coated Poly(vinylidene fluoride) thin films. Structural characteristics of the thin films were comparatively investigated by FT-IR and XRD in relation with the organic solvent and post-deposition annealing temperature.

• Proceedings of the Korean Society of Rheology Conference
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• 2002.05a
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• pp.29-32
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• 2002

• Proceedings of the Korean Fiber Society Conference
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• 2000.04a
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• pp.265-269
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• 2000

• Proceedings of the Korean Fiber Society Conference
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• 1987.06a
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• pp.51-51
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• 1987

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.271-274
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• 2001

최근 압전성 및 유전성, 비선형 광학전도성 등과 같은 특성을 갖는 전기전자 및 광기능성 고분자에 대한 연구가 많이 이루어지고 있다[1-2]. 그 중에서 압전 및 초전성을 나타내는 대표적 유기 고분자인 poly(vinylidene fluoride)(PVDF)의 경우 압전성을 향상시키기 위하여 vinylidene. fluoride(VDF)나 vinyl fluoride(VF), trifluoroethylene(TrFE) 등과 공중합시킨 고분자들에 대한 연구가 활발히 진행되어 왔다[3-4]. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.437-438
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• 2002

Poly(vinylidene fluoride)(PVDF)는 우수한 화학적 특성을 갖는 불소계 고분자로서 엔지니어링 플라스틱, 압전성 소재 및 봉합사용 소재로 이용되고 있다. 최근에는 PVDF의 화학적 개질을 통하여 전도성 고분자나 탄소섬유화 등의 기능성 소재로 만들려는 연구가 흥미롭게 이루어지고 있다. PVDF를 알칼리 처리하여 주쇄에 공액이중결합을 도입함으로써 전도성 고분자용 소재 또는 접착력이 개선된 PVDF 소재를 만들 수 있다. (중략)

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.380-382
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• 1989

Dielectric breakdown strength (Eb) of thin Poly(Vinylidene Fluoride ; PVDF) film is studied in the temperature range between 4.2 K and 400 K. The results of this study can be summerized as follows. 1) Temperature dependence of dielectric breakdown strength (Eb) can be devided into high and low temperature regions. The critical temperature (Tc) at which two regions are devided depends on applied voltage. 2) Dielectric breakdown strength (Eb) by pulse voltage is higher than that by DC voltage. Especially this difference is remarkable at low temperature.

• Korea-Australia Rheology Journal
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• v.20 no.4
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• pp.213-220
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• 2008

The effects of temperature on the rheological properties of the solutions of poly(vinylidene fluoride-co-hexafluopropylene) (PVDF-HFP) in dimethyl acetamide (DMAc) were investigated in terms of frequency and concentration. The effects of temperature on the intrinsic viscosity of the solutions were discussed. In dynamic rheological measurement, the concentrated solutions showed a little unexpected rheological response; as temperature was increased dynamic viscosity was increased and the solutions exhibited more noticeable Bingham body character over the temperature range, 30 to $70^{\circ}C$. In addition, the solution gave longer relaxation time, lower value of loss tangent and higher value of yield stress at higher temperature and at higher concentration. On the other hand, the dilute solutions revealed that intrinsic viscosity was decreased and its Huggins constant was increased with increasing temperature. These physical parameters suggested that the increase of viscosity with increasing temperature resulted from the localized gelation of PVDF-HFP due to reduced solubility to the solvent.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.41-48
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• 2011

The wettabilities of the partially fluorinated polymers (ethylene-tetrafluoroethylene copolymer (ETFE), ethylenechlorotrifluoroethylene copolymer (ECTFE), and poly(vinylidene fluoride) (PVDF)) were investigated by contact angle measurements. Zisman plots for ETFE and ECTFE exhibited linear relationships, while the Zisman plot for PVDF showed a slight curvature, which was interpreted to indicate strong non-dispersive interactions between the surface and the contacting liquids. The Lifshitz-van der Waals forces of the fluoropolymers were estimated to increase in the order of ETFE < PVDF $\ll$ ECTFE. An evaluation of the polar or "acid-base" interaction energies showed that PVDF, which possesses the most acidic hydrogens among the examined fluoropolymers, has the strongest acid-base interactions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.437-440
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• 2004

The radiation-induced changes taking place in poly(vinylidene fluoride)(PVDF) exposed to $^{60}Co\;\gamma-ray$ irradiation were investigated in correlation with the applied doses. Samples were irradiated in air at room temperature by $^{60}Co\;\gamma-ray$ to doses in the range of 200 to 1000 kGy. Various properties of the irradiated PVDF were studied using nm, differential scanning calorimetry(DSC) and gel fraction. $^{60}Co\;\gamma-ray$ irradiation was found to induce changes in chemical, thermal, structural properties of PVDF and such changes vary depending on the radiation dose.