بررسی اثر میزان ماده کف زای شیمیایی و آرد چوب بر ویژگیهای مکانیکی، چگالی و ریخت شناسی چندسازه سبک شده هیبریدی پلی اتیلن سنگین/ اتیلن وینیل استات/آرد چوب

نوع مقاله: مقاله پژوهشی

نویسندگان

1 عضو هیأت علمی دانشگاه آزاد اسلامی واحد ملایر

2 استادیار دانشگاه آزاد اسلامی واحد ملایر

چکیده

در این تحقیق تأثیر میزان ماده کف‌زای شیمیایی و آرد چوب  بر ویژگیهای مکانیکی، چگالی و ریخت شناسی چندسازه سبک شده هیبریدی پلی اتیلن سنگین/ اتیلن وینیل استات/ آرد چوب مورد بررسی قرار گرفت. برای این منظور، چندسازه‌ها با استفاده از فرآیند اختلاط در یک مخلوط کن داخلی تهیه و سپس به روش تک مرحله‌ای (Batch) فوم شدند. سپس خواص مکانیکی شامل مقاومت خمشی، مدول خمشی و کششی و چگالی اندازه‌گیری شدند. ریخت شناسی نمونه‌ها نیز با عکسبرداری با میکروسکوپ الکترونی(SEM) مورد ارزیابی قرار گرفت. نتایج نشان داد با افزایش میزان آرد چوب، مقاومت خمشی، مدول خمشی و کششی و چگالی افزایش یافت. در حالی‌که با افزایش میزان ماده کف زای شیمیایی و EVA، خواص مکانیکی و چگالی چندسازه‌های فوم شده کاهش یافت. همچنین آرد چوب به عنوان عامل هسته‌گذار عمل کرده و منجر به کاهش اندازه سلولی و افزایش چگالی سلولی گشت. از طرفی، EVA  با افزایش گرانروی مذاب ماتریس پلیمری، نقش مهمی را در فرآیند فوم شدن ایفاء نمود. به گونه‌ای که نمونه‌های دارای میزان EVA بیشتر، دارای بیشترین میزان چگالی سلولی و کمترین اندازه سلولی گشتند.
 

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