نانوکامپوزیت‌های پلی‌یورتانی بر پایه هیدروکسیدهای دوگانه لایه‌ای: مروری بر روش‌های سنتز و کاربردها

نوع مقاله : مروری

نویسندگان

1 اصفهان، دانشگاه اصفهان، دانشکده شیمی، گروه شیمی پلیمر، کد پستی 73441-81746

2 تهران، پژوهشگاه پلیمر و پتروشیمی ایران، پژوهشکده علوم، گروه پلی‌یورتان و مواد پیشرفته، صندوق پستی ۱۱۲-۱۴۹۷۵

چکیده

امروزه توسعه نانوکامپوزیت‌های پلیمری به‌منظور بهبود استحکام مکانیکی، پایداری گرمایی، کاهش هزینه ساخت و فراهم‌سازی امکان استفاده برای کاربردهای ویژه مورد توجه زیادی قرار گرفته است. پلی‌یورتان‌ها به‌عنوان گروه مهمی از پلیمرها، دامنه گسترده و کنترل‌پذیری از خواص فیزیکی و مکانیکی را به‌دلیل امکان استفاده از مواد اولیه گوناگون مانند پلی‌ال‌ها و ایزوسیانات‌ها نشان می‌دهند. تنوع و کنترل‌پذیری خواص انواع مختلف پلی‌یورتان‌ها مانند الاستومرها، الیاف، اسنفج‌ها، هیدروژل‌ها و پوشش‌ها، این دسته از پلیمرها را به گزینه مناسبی برای کاربرد در زمینه‌های گوناگون نظیر حمل‌و‌نقل، پوشاک، مبلمان و زیست‌پزشکی تبدیل کرده است. مطالعات فراوانی در راستای تهیه نانوکامپوزیت‌های پلی‌یورتانی با استفاده از نانوساختارهای متنوعی مانند نانوذرات گرافن، نانولوله‌های کربن، اکسیدهای فلزی و سایر مواد انجام شده است. نانوساختارهای هیدروکسیدهای دوگانه لایه‌ای (LDH)، دسته‌ای از ترکیبات لایه‌ای معدنی و دوست‌دار محیط‌زیست با قابلیت تبادل آنیون هستند. لایه‌های این نانوساختارها بار مثبت دارند و فضای میان لایه‌ها نیز آنیون‌ها و آب وجود دارد. به‌دلیل ساختار لایه‌ای و ظرفیت تبادل آنیون زیاد، LDH‌ها در زمینه‌های بی‌شماری از قبیل کاتالیزگرها، رهایش دارو، جذب و جداسازی گازها و آلاینده‌های زیست‌محیطی و نیز استفاده به‌عنوان جاذب فرابنفش، بازدارنده خوردگی و بازدارنده شعله در پلیمرها استفاده می‌شوند. طی سال‌های اخیر از نانوساختارهای LDH در تهیه نانوکامپوزیت‌های پلی‌یورتانی به‌منظور بهبود خواص گوناگون نظیر خواص مکانیکی، گرمایی و مقاومت شعله در پلیمرها استفاده شده است. در مقاله حاضر، افزون بر معرفی نانوساختارهای LDH، پلی‌یورتان‌ها و کاربرد آن‌ها، نانوکامپوزیت‌های پلی‌یورتانی برپایه LDH نیز بحث می‌شود.

کلیدواژه‌ها


عنوان مقاله [English]

Polyurethane Nanocomposites Based on Layered Double Hydroxides: A Review on Their Syntheses and Applications

نویسندگان [English]

  • Abbas Mohammadi 1
  • Hossein Abdolvand 1
  • Mehdi Barikani 2
1 Department of Polymer Chemistry, Faculty of Chemical, University of Isfahan, Postal Code 81746-73441, Isfahan, Iran
2 Department of Polyurethane and Advanced Materials, Faculty of Science, Iran Polymer and Petrochemical Institute, P.O. Box 14975-112, Tehran, Iran
چکیده [English]

Nowadays, polymer nanocomposites have attracted much attention in research activities due to their high mechanical strength, high thermal stability, low-cost, with possibility for their applications in many areas. Polyurethanes (PUs), as a main group of polymers, show a diverse and controllable range of physical and mechanical properties due to their tailored properties depending on the nature of precursors like polyols and isocyanates. This diversity and controllability of their properties make different types of PUs (elastomers, fibers, foams, hydrogels, and coatings) preferred candidates for a variety of uses, including transportation, clothing, furniture, and biomaterials. Many studies have been performed on polyurethane nanocomposites using different types of nanostructures such as graphene-like nanosheets, carbon nanotubes, metal oxides, and so on. Layered double hydroxides (LDHs) are eco-friendly layered mineral nanostructures with positively charged layers and anion-exchange capability. Depending on the types of anions and structure of layers, the LDHs nanostructures can be used broadly for the applications such as catalysts, drug delivery, separation technology, and also as a UV absorbent, corrosion, and a flame inhibitor for polymers. Recently, LDHs nanostructures are used in the fabrication of polyurethane nanocomposites to improve their mechanical, thermal, and flame properties. In this review, in addition to the description of LDH nanostructures, polyurethanes and their applications, LDH-based polyurethane nanocomposites are discussed in detail.

کلیدواژه‌ها [English]

  • nanocomposite
  • polyurethane
  • layer double hydroxides
  • synthesis
  • application
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