نویسندگان

پردیس دانشکده های فنی دانشگاه تهران، دانشکده مهندسی، گروه مهندسی متالورژی و مواد ، تهران، ایران.

چکیده

در یک دهه گذشته تحقیقات گسترده‌ای در زمینه‌ پوشش‌های خودترمیم‌شونده صورت گرفته است. در مقاله حاضر به تولید و مشخصه‌یابی میکروکپسول‌های حاوی رزین اپوکسی (به عنوان ماده ترمیم‌کننده) پرداخته شده است. ماده تشکیل‌دهنده پوسته میکروکپسول‌ها اوره- فرمالدهید است که با استفاده از روش پلیمریزاسیون درجا تولید شده است. این کپسول‌ها جهت استفاده در پوشش‌های خودترمیم‌شونده حاوی میکروکپسول ساخته شده‌اند. بررسی خواص مختلف میکروکپسول‌های تولیدی با استفاده از ابزارهای مختلفی نظیر میکروسکوپ الکترونی روبشی (SEM)، طیف‌سنجی تبدیل فوریه مادون قرمز (FTIR)، آنالیز توزین حرارتی (TGA) و گرماسنجی افتراقی (DSC) صورت گرفت. نتایج به‌دست آمده حاکی از تولید موفقیت‌آمیز این میکروکپسول‌ها است. قطر میکروکپسول‌های تولیدی به طور متوسط 100 میکرون است و دارای سطح خارجی مملو از نانوذرات اوره- فرمالدهید می‌باشد که به چسبندگی بیشتر این میکروکپسول‌ها به زمینه دلخواه کمک می‌نماید. میکروکپسول‌های تولیدی دارای پایداری شیمیایی و حرارتی مناسب جهت کاربردهای مختلف در زمینه پوشش‌های خودترمیم‌شونده هستند.

کلیدواژه‌ها

عنوان مقاله [English]

Synthesis and Characterization of Microcapsules Containing Epoxy Resin (Epon 828) for Self-healing Coatings

نویسندگان [English]

  • Tahere Ebrahimi Sadrabadi
  • Saeid reza Allah karam
  • Naser Towhidi

University of Tehran , College of Engineering, Department of Metallurgy and Materials Engineering, Tehran, Iran.

چکیده [English]

In the field of coatings, extensive laboratory research has been conducted in the last decade. In the present work, effectiveness of epoxy resin filled microcapsules was investigated for future using in healing of cracks generated in coatings. Microcapsules were prepared by in situ polymerization of urea–formaldehyde resin to form shell over epoxy resin droplets. The optimal process parameters for synthesizing the microcapsules were selected. The as-synthesized microcapsules were studied by various characterizations techniques, including scanning electron microscope (SEM), Fourier transform-infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC).
The results indicate that microcapsules containing epoxy resins can be synthesized successfully. The average size is around 100 µm. The rough outer surface of microcapsule is composed of agglomerated urea–formaldehyde nanoparticles. The microcapsules basically exhibit good storage stability at room temperature, and they are chemically stable before the heating temperature is up to approximately 250 °C.

کلیدواژه‌ها [English]

  • Microcapsule
  • Epoxy
  • Self-healing
  • Smart coating
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