اثر هم‌افزایی آمونیوم پلی‌فسفات‌ و مونت‌موریلونیت آلی اصلاح‌شده بر خواص تأخیراندازی شعله و اسفنجی‌شدن زیست‌کامپوزیت پلی‌اتیلن پرچگالی-پودر پوست گردو

نوع مقاله: پژوهشی

نویسندگان

1 اصفهان، دانشگاه اصفهان، گروه مهندسی شیمی، صندوق پستی 8174673441

2 بوشهر، دانشگاه خلیج فارس، دانشکده نفت، گروه مهندسی شیمی، صندوق پستی7516913817

3 مرودشت، دانشگاه آزاد اسلامی، واحد مرودشت گروه مهندسی شیمی، صندوق پستی 13119-73711

4 آبادان، دانشگاه صنعت نفت، دانشکده نفت شهید تندگویان، صندوق پستی 63187143314

چکیده

اثر هم‌افزایی مونت‌موریلونیت آلی اصلاح‌شده (OMMT) و آمونیوم پلی‌فسفات‌ (APP) بر بهبود پایداری گرمایی و تأخیراندازی شعله زیست‌کامپوزیت پلی‌اتیلن پرچگالی-پودر پوست گردو (HDPE/WSP) با استفاده از آزمون‌های شاخص حدی اکسیژن (LOI)، گرما‌‌وزن‌سنجی (TGA) و گرماسنجی مخروطی بررسی شد. داده‌های حاصل از آزمون شاخص حدی اکسیژن اثر هم‌افزایی OMMT را بر APP نشان می‌دهد، به‌طوری که در نمونه دارای phr 9 از OMMT و phr 15 از APP شاخص حدی اکسیژن به %28 رسید. براساس نتایج آزمون گرماوزن‌سنجی تجزیه تمام مواد در دو مرحله انجام شد. اضافه‌کردن APP و OMMT فرایند تجزیه در مرحله اول را تسریع کرده و زغال باقی‌مانده بیشتری تولید کرد. فرایند تجزیه مرحله دوم نیز در دمای بیشتری انجام شد. این افزایش دما را می‌توان ناشی از اثر OMMT و APP در ایجاد لایه‌ای از زغال دانست که مانع از انتقال گرما و جرم بین سطح و پلیمر مذاب شده و در نتیجه تأخیراندازی شعله زیست‌کامپوزیت افزایش می‌یابد. با اضافه‌شدن APP و OMMT و در پی آن تشکیل لایه زغال، HRR و MLR نیز کاهش یافت. اسفنج‌های میکروسلولی زیست‌کامپوزیت HDPE/WSP به روش ناپیوسته و با استفاده از نیتروژن به‌عنوان عامل دمش تولید شدند. اندازه سلول‌ها و چگالی نسبی زیست‌کامپوزیت تابع قوی از محتوای APP و OMMT و شرایط عملیاتی بودند. با افزایش محتوای APP در زیست‌کامپوزیت، چگالی نسبی کاهش و سپس افزایش یافته و اندازه سلول‌ها افزایش یافت. با اضافه‌شدن OMMT اندازه سلول‌ها کاهش و چگالی نسبی افزایش پیدا کرد. با افزایش دما و فشار اشباع چگالی نسبی کاهش یافت.

کلیدواژه‌ها


عنوان مقاله [English]

Synergistic Effect of Intumescent Flame Retardant and Organically Modified Montmorillonite on Flame-Retardant and Foaming Properties of High Density Polyethylene/Walnut Shell Powder Biocomposites

نویسندگان [English]

  • Ebrahim Bahreyni 1
  • Mansure Farid 2
  • Mohamadali Fakhari 3
  • Mohammad Farid 4
1 Department of Chemical Engineering, Isfahan University, P.O. Box: 8174673441, Isfahan, Iran
2 Chemical Engineering Group, Persian Gulf University, Post Code: 7516913817, Boushehr, Iran
3 Department of Chemical Engineering, College of Engineering, Marvdasht Branch, Islamic Azad University, Postal Code: 73711-13119, Marvdasht, Iran
4 Abadan Faculty of Petroleum (Shahid Tondgouyan), Petroleum University of Technology, Abadan, Iran
چکیده [English]

The synergistic effects of organic montmorillonite (OMMT) and ammonium polyphosphate (APP) on flame retardant enhancement of High density polyethylene/walnut shell powder (HDPE/WSP) biocomposite were investigated by using the limiting oxygen index (LOI), thermogravimetric analysis (TGA) and Cone calorimeter test. The LOI data show that OMMT has a synergistic flame retardant effect with APP and the LOI value reaches 28%for the samples containing 9 phr OMMT and 15 phr APP. The TGA and Cone calorimeter data demonstrate that the incorporation of OMMT and APP is very effective in enhancing the thermal stability ofHDPE/WSP/OMMT/APP system. Based on The results of the thermogravimetric analysis all samples decomposed in two decomposition stages. Addition of OMMT and APP alsocatalyzed the first stage of decomposition, and produced morechar residual. The second decomposition stage conductedin higher temperature. These transitionsare due to the OMMTincorporates with APP to produce a charred layer and prevents the heatand mass transfer between surface and melting polymer, lead toimprovethe fire resistance of the composites.Addition of OMMT and APP and consequently production of charred layer also decreased HRR and MLR values.Microcellular HDPE/WSP biocomposite foams were prepared with batch foaming apparatus using nitrogen as blowing agent. In microcellular biocomposites, therelative density and cell size were a strong function of APP and OMMT contentand processing conditions. With increasing of APP content, the relative density decreased and then increased and the cell size increased.Addition of OMMTresulting in smaller cell size and higher relative density. The relative density decreased with increasing of saturation temperature and pressure.

کلیدواژه‌ها [English]

  • foams
  • biocomposite
  • walnut shell
  • HDPE
  • flame retardant

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