مروری بر روش‌های مختلف تغییر خواص پیزوالکتریک در پلی‌(وینیلیدن فلوئورید)

نوع مقاله: پژوهشی

نویسندگان

1 تهران، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات تهران، باشگاه پژوهشگران و نخبگان، صندوق پستی 775-14515

2 تهران، دانشگاه آزاد اسلامی، واحد تهران جنوب، گروه مهندسی نساجی و پلیمر، صندوق پستی 11365-4435

3 تهران، پژوهشگاه پلیمر و پتروشیمی ایران، پژوهشکده فرایند، گروه پلاستیک، صندوق پستی 112-14975

4 تهران، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، گروه مهندسی نساجی، صندوق پستی 775-14515

5 تهران، دانشگاه آزاد اسلامی، واحد تهران جنوب، گروه مهندسی برق، کد پستی 1777613651

چکیده

امروزه تأمین انرژی الکتریکی از انرژی‌های تجدیدپذیر مانند انرژی مکانیکی، گرمایی و خورشیدی گسترش یافته است. مواد پیزوالکتریک از مناسب‌ترین گزینه‌ها برای تأمین انرژی الکتریکی از انرژی مکانیکی موجود در طبیعت مانند نیروی مکانیکی، ارتعاش و حرکات بدن انسان است. کاربرد برداشت‌کننده‌های پیزوالکتریک به‌منظور تأمین انرژی الکتریکی در قطعات الکترونیکی خودشارژشونده یا حسگرهای بی‌سیم با توان کم برای حذف باطری یا کابل است. در واقع، خاصیت پیزوالکتریک خاصیتی از موادی ویژه است که قابلیت تبدیل انرژی مکانیکی به الکتریکی و برعکس را فراهم می‌کند. خاصیت پیزوالکتریک ابتدا در سرامیک‌ها کشف شد. اما به‌دلیل نیاز به مواد پیزوالکتریک با سطح بزرگ و انعطاف‌پذیری زیاد در بسیاری از کاربردها و نیز قیمت نسبتاً ارزان و فناوری تولید ساده پلیمرها در مقایسه با سرامیک‌ها، پلیمرها به‌طور گسترده به‌کار گرفته شدند. پلی‌(وینیلیدن فلوئورید) (PVDF)، پلیمری نیمه‌بلوری با خواص فروالکتریک و پیزوالکتریک است و پنج شکل بلوری دارد. فاز β، قطبی است و به‌دلیل بیشترین ممان دوقطبی و قطبش دائمی خاصیت پیرو و پیزوالکتریک نشان می‌دهد. در این مقاله، ابتدا PVDF معرفی و سپس روش‌های مختلف برای تعیین و اندازه‌گیری فازهای مختلف آن مرور شده است. در نهایت، روش‌های مختلف از جمله کشش مکانیکی، فشار زیاد، سردکردن مذاب، استفاده از حلال‌های قطبی، قطبش زیر کشش و میدان الکتریکی قوی، آمیخته‌سازی با پلیمرها و الکتروریسی و اثر افزودن انواع مواد افزودنی مانند نانولوله کربن، خاک‌رس، فلزات و نمک‌های فلزی و سرامیک‌ها بر افزایش فاز قطبی β بحث و بررسی شده است.

کلیدواژه‌ها


عنوان مقاله [English]

Different Methods of Changing Piezoelectric Properties in Poly(vinylidene fluoride): A Review

نویسندگان [English]

  • Mina Abasipour 1
  • Ramin Khajavi 2
  • Ali Akbar Yousefi 3
  • Mohamad Ismail Yazdanshenas 4
  • Farhad Razaghian 5
1 Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, P.O. Box 14515-775, Tehran, Iran
2 Department of Textile and Polymer Engineering, South Tehran Branch, Islamic Azad University, P.O. Box 4435-11365, Tehran, Iran
3 Department of Plastics, Faculty of Polymer Processing, Iran Polymer and Petrochemical Institute, P.O. Box 14975-112, Tehran, Iran
4 Department of Textile Engineering, Science and Research Branch, Islamic Azad University, B.O. Box 14515-775, Tehran, Iran
5 Department of Electrical Engineering, South Tehran Branch, Islamic Azad University, Postal Code 1777613651, Tehran, Iran
چکیده [English]

Recently, the supply of electrical energy from sustainable and renewable energies such as mechanical, thermal and solar energy has been expanded. Piezoelectric materials are one of the best alternatives for supplying electrical energy from the mechanical energy available in nature such as mechanical force, vibration and human body movements. The applications for piezoelectric energy harvester include low power electronics or wireless sensing at relatively lower power levels (nW to mW) with an aim to reduce a reliance on batteries or electrical power through cables and realize fully autonomous and self-powered systems. In fact, the piezoelectric property is the property of a special material that enables the conversion of mechanical energy into electrical energy and vice versa. Piezoelectric property was discovered in ceramics for the first time. However, because of the need to piezoelectric materials with large surfaces and high flexibility in many applications, and the relatively low price and simple manufacturing technology of polymers in comparison with ceramics, polymers are used extensively. Poly(vinylidene fluoride) (PVDF) is a semicrystalline polymer with ferroelectric and piezoelectric properties. It has five distinctive configurations. β-phase is a polar phase showing significant piezoelectricity and pyroelectricity due to the highest dipolar moment and spontaneous polarization. In this review, PVDF polymer is introduced and then the different strategies for identification and quantification of PVDF phases are summarized. Finally, various methods including stretching, high pressure, ultra-fast cooling, melt quenching, using polar solvents, poling, copolymerization, polymer blending, electrospinning and filler addition such as carbon nanotube, clay, metals and metal salts, ceramics and etc., have been discussed for β-phase enhancement.

کلیدواژه‌ها [English]

  • poly(vinylidene fluoride)
  • piezoelectric
  • pyroelectric
  • β phase
  • energy harvesting
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