اثر نانوذرات خاک‌رس بر خواص جریان و گرمایی آمیخته پلی‌پروپیلن- کوپلیمر (استیرن - اتیلن - بوتیلن – استیرن) پیوندخورده با مالئیک انیدرید

نوع مقاله: پژوهشی

نویسندگان

1 دانشگاه آزاد اسلامی واحد پارسیان، پارسیان کدپستی ۷۹۷۷۱۶۵۱۹۳

2 دانشگاه آزاد اسلامی واحد فسا، فسا کدپستی ۸۹۸۱۸-۷۴۶۱۷

3 دانشگاه صنعتی امیرکبیر، دانشکده مهندسی پلیمر، تهران صندوق پستی ۱۵۸۷۵-۴۴۱۳

4 تهران‌ پژوهشگاه پلیمر و پتروشیمی ایران، پژوهشکده فرایند، گروه فرایند و مهندسی لاستیک، صندوق پستی ۱۱۲-۴۹۷۵

5 هنرستان مطهره، داراب کدپستی ۷۴۸۱۶-۹۶۴۶۵

چکیده

هدف از این پژوهش، بررسی اثر نانوذرات خاک رس (Cloisite® 15A) بر رفتار جریان و خواص مکانیکی و گرمایی آمیخته پلی‌پروپیلن/کوپلیمر (استیرن - اتیلن - بوتیلن - استیرن) پیوند خورده با مالئیک انیدرید SEBS-g-MA)، ۱۵% وزنی) است. بدین منظور، کامپوزیت­هایی برپایه این آمیخته و مقادیر مختلف خاک‌رس (۱، ۳  و ۵% وزنی) با استفاده از مخلوط کن داخلی در دمای ۱۹۰ درجه سلسیوس و سرعت چرخش  ۷۵ دور بر دقیقه به مدت ۱۲ دقیقه به شکل مذاب تهیه شدند. سپس نمونه ­هایی با ابعاد مورد نیاز برای آزمون­ های مختلف با استفاده از پرس گرم قالب‌گیری شدند. از آزمون پراش پرتو X و میکروسکوپ الکترونی عبوری (TEM) برای بررسی ساختار و شکل شناسی نمونه‌­ها استفاده شد. همچنین رفتار جریان، خواص مکانیکی و گرمایی همه نمونه­‌های تهیه شده با استفاده از روش­‌های استاندارد اندازه‌گیری شدند. نتایج آزمون پراش پرتو X و میکروسکوپ الکترونی عبوری، تشکیل نانوکامپوزیت­‌هایی با ساختارهای پراکنشی ورقه‌­ای و بین لایه‌­ای را تأیید می­‌کنند. در همه نانوکامپوزیت­‌های تهیه شده، تعادل بین استحکام و چقرمگی با افزودن همزمان کوپلیمر (SEBS-g-MA) و نانوذرات خاک رس وجود دارد. نتایج اندازه گیری خواص رئولوژیکی نیز نشان می‌­دهد، با افزایش سرعت برش، گرانروی ظاهری همه نمونه­‌ها کاهش می‌­یابد (رفتار نازک شدن برشی). افزودن نانوذرات خاک رس به آمیخته و افزایش مقدار آن، شاخص جریان مذاب (MFI) نمونه­‌ها را کاهش داده است. افزون براین، وجود خاک رس و افزایش مقدار آن اثر کمی بر خواص گرمایی داشته و افزایش کم در دما در درصد بلورینگی، دمای انحراف گرمایی و نیز نقطه نرم‌شدگی ویکات نمونه­‌ها افزایش کمی حاصل شده است.

کلیدواژه‌ها


عنوان مقاله [English]

Nanoclay Effect on the Flow and Thermal Properties of PP/SEBS-g-MA Blend

نویسندگان [English]

  • M. Ranjbar 1
  • M. Sabetzadeh 2
  • A. Arefazar 3
  • G. Bakhshandeh 4
  • Aazam Ranjbar 5
1 Islamic Azad University, Parsian Branch, Parsian 79771-65193, Iran
2 Chemical Engineering Department, Polymer Group, Isfahan University of Technology, Isfahan 84156-83111, Iran
3 Polymer Engineering Department, Amirkabir University of Technology, Isfahan 15875-4413, Iran
4 Department of Rubber Engineering, Faculty of Processing, Iran Polymer and Petrochemical Institute, P.O. Box: 14975-112, Tehran, Iran
5 Motahhareh high school, Darab 74816-96465, Iran
چکیده [English]

The effect of nanoclay (Cloisite® 15A) was studied in relation to the flow behavior, mechanical and thermal properties of polypropylene/maleic anhydride-g-(styrene-ethylene-butylene-styrene) triblock copolymer (PP/SEBS(15%)-g-MA) blend. In this regard, the composites based on the blend and various amounts of nanoclay (1,3,5 wt%) were melt compounded using an internal mixer at the temperature of 190°C, rotor speed of 75rpm for 12min. The prepared samples were compression molded in a hot-press machine under the conditions of 190°C, 31 MPa pressure for 9 min to obtain the sheets in various thicknesses. The sheets were then cooled to ambient temperature with cooling water at the rate of 1.5°C.s-1. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to study the structure and morphology of the samples. In addition, the mechanical and thermal properties were determined by standard methods. The results of X-ray diffraction and transmission electron photographs confirmed both exfoliated and intercalated structures in the prepared samples. There were balanced strength/toughness properties in all the prepared nanocomposites by addition of both SEBS-g-MA and clay simultaneously. The measurement of rheological properties showed that as the shear rate increased, the apparent viscosity of the samples decreased (shear thinning behavior). Gradual increase in incorporation of nanoclay also decreased the melt flow index (MFI) values. In addition, increases in nanoclay content had an insignificant effect on the thermal behavior and in that respect there were slight increases in degree of crystallinity, heat deflection temperature (HDT) as well as Vicat softening point by slight increase in temperatureThe effect of nanoclay (Cloisite® 15A) was studied in relation to the flow behavior, mechanical and thermal properties of polypropylene/maleic anhydride-g-(styrene-ethylene-butylene-styrene) triblock copolymer (PP/SEBS(15%)-g-MA) blend. In this regard, the composites based on the blend and various amounts of nanoclay (1,3,5 wt%) were melt compounded using an internal mixer at the temperature of 190°C, rotor speed of 75rpm for 12min. The prepared samples were compression molded in a hot-press machine under the conditions of 190°C, 31 MPa pressure for 9 min to obtain the sheets in various thicknesses. The sheets were then cooled to ambient temperature with cooling water at the rate of 1.5°C.s-1. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to study the structure and morphology of the samples. In addition, the mechanical and thermal properties were determined by standard methods. The results of X-ray diffraction and transmission electron photographs confirmed both exfoliated and intercalated structures in the prepared samples. There were balanced strength/toughness properties in all the prepared nanocomposites by addition of both SEBS-g-MA and clay simultaneously. The measurement of rheological properties showed that as the shear rate increased, the apparent viscosity of the samples decreased (shear thinning behavior). Gradual increase in incorporation of nanoclay also decreased the melt flow index (MFI) values. In addition, increases in nanoclay content had an insignificant effect on the thermal behavior and in that respect there were slight increases in degree of crystallinity, heat deflection temperature (HDT) as well as Vicat softening point by slight increase in temperature.The aim of this work is to study effect of nanoclay (Cloisite® 15A) on the flow behavior, mechanical and thermal properties of polypropylene/maleic anhydride grafted-(styrene-ethylene-butylene- styrene) triblock copolymer (PP/15%SEBS-g-MA) blend. In this regard, the composites based on the blend and various amounts of nanoclay (1,3,5 wt.%) were melt compounded using an internal mixer at the temperature of 190oC, rotor speed of 75rpm for 12min. The prepared samples were then compression molded in a hot-press machine under the conditions of 190°C, 31 MPa pressure, for 9 min to obtain the sheets in various thicknesses. Afterwards, the plates were cooled to ambient temperature with cooling water at the rate of 1.5oC.s-1. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to study the structure and morphology of the samples. In addition, the mechanical and thermal properties were carried out by means of the standard methods. The results of X-ray diffraction and transmission electron photographs confirm both exfoliated and intercalated structures in the prepared samples. There is balanced strength/toughness properties in all the prepared nanocomposites via addition both SEBS-g-MA and clay simultaneously. The measurement of rheological properties show that as the shear rate increases, the apparent viscosity of the samples decreases (shear thinning behavior). Incorporation of nanoclay and increasing its content also decreases the melt flow index (MFI) values. In addition, increase in the nanoclay content have the insignificant effect on the thermal behavior so that slight increase in crystallinity temperature/degree, heat deflection temperature (HDT) as well as vicat softening point are obtained.

کلیدواژه‌ها [English]

  • : nanoclay
  • Polypropylene
  • sebs-g-ma copolymer
  • flow behavior
  • thermal properties