اثر قیر قطران بر بهبود کارایی عایق حرارتی ایروژل کربنی بر پایه رزین نووالاک

نوع مقاله : پژوهشی اصیل

نویسندگان

1 دانشجوی دانشگاه تربیت مدرس

2 عضو هیات علمی گروه مهندسی مواد دانشگاه تربیت مدرس

3 عضو هیات علمی گروه مهندسی پلیمر دانشگاه تربیت مدرس

چکیده
ژوهش حاضر در راستای سنتز ایروژل کربنی ارزان‌قیمت با خواص مطلوب و با رویکرد عایق حرارتی است. در این پژوهش از رزین ارزان‌قیمت نوولاک به‌عنوان ماده اولیه تولید ایروژل پلیمری و روش خشک‌کردن محیطی استفاده شد؛ سپس قیر قطران زغال‌سنگ به‌وسیله غوطه‌وری نمونه‌های پلیمری در محلول قیر به نمونه‌ها اضافه شد. در مرحله‌ی بعد، ایروژل‌های پلیمری نوولاک- قیر، در عملیات حرارتی گرماکافت به ایروژل‌های نانو ساختار کربنی تبدیل شدند. نتایج حاصل نشان داد که با این روش می‌توان به ایروژل‌هایی با ساختار نانو و با چگالی قابل‌پیش‌بینی دست یافت؛ همچنین با بررسی ریزساختار و ریخت‌شناسی این ایروژل‌ها مشخص شد که این ایروژل‌ها دارای تخلخل بالا، چگالی پایین (حدود 4/0-1/0) و مساحت سطح ویژه بالا (حدود 600) هستند. قیر زغال‌گذاری بالایی از خود نشان داد و افزودن آن باعث بهبود خواص حرارتی حداقل به‌میزان 100 ثانیه تاخیر در بالا رفتن دما در آزمون تاریخچه حرارتی گردید؛ که نتیجه آن دستیابی به عایقی با عملکرد حفاظت حرارتی مطلوب‌تر بود.

کلیدواژه‌ها

موضوعات


عنوان مقاله English

Effect of Coal Tar Pitch on Improvement of Thermal Insulation Performance of Carbon Aerogels Based on Novolac Resin

چکیده English

The current study is based on synthesis a low cost carbon aerogel with improved properties and thermal insulator approach. In this work cheap novolac resin are used as a raw material for producing polymer aerogel by ambient drying method; then the coal tar pitch is added to samples by immerging them in pitch solution. In next step novolac-pitch polymer aerogels is converted to carbon nano-structure aerogels by pyrolysis heat treatment at inert atmosphere. The results proved, nano-structured aerogels with predictable density will be achieved by this method; also by studying on microstructure and morphology of aerogels it founded these aerogels have high porosity, low density(about 0.1-0.4 g/cm3) and high specific surface area (about 600 m2/g). The charring pitch was a lot and using of it made improved thermal properties that resulted in at least 100s delay in increasing temperature in time-temperature history test; as a result a high performance thermal insulator achieved.

کلیدواژه‌ها English

Carbon aerogel
Novolac resin
Coal tar pitch
Pyrolysis
Thermal properties
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