تهيه كامپوزيت EPDM/MWCNT با خواص مكانيكي-رئولوژيكي بهبود يافته از طريق اصلاح سيلاني پليمر در غلظت هاي مختلف نانو لوله كربن

چكيده انگليسي :

Preparation of EPDM MWCNT Composite with high Mechanical and Rheological Properties by Silane Modification of Polymer using Various Concentration of MWCNT Fatemeh Khademeh Molavi f khademehmolavi@ce iut ac ir Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Rohollah Bagheri bagheri@cc iut ac ir Ghaseme Naderi g naderi@ippi ac ir Abstract The use of organic or inorganic filler has become ubiquitous in polymer systems Polymer composites are manufactured commercially for many diverse applications such as sporting goods aerospace components automobiles etc In the last 20 years there has been a strong emphasis on the development of polymeric nanocomposites where at least one of the dimension of the filler material is of the order of a nanometer The final product does not have to be in nanoscale but can be micro or macroscopic in size In general the unique combination of the nanomaterial s characteristics such as size mechanical properties and low concentrations necessary to effect change in a polymer matrix couples with the advanced characterization and simulation techniques now available have generated much interest in the field of nanocomposites In addition many polymer nanocomposites can be fabricated and processed in ways similar to that of conventional polymer composites making them particularly attractive from a manufacturing point f view In this study the composites based on ethylene propylene diene monomer EPDM and multi walled carbon nanotube MWCNT have been prepared by melt compounding The effect of silane grafting on properties of MWCNT EPDM composite were investigated To overcome the problem of non uniform dispersion of MWCNTs in polymer matrix Vinyl trimethoxy silane was used as coupling agent The melt grafting of VTMS onto EPDM chains was done in an internal mixer The effect of MWCNT concentration on cure characteristics microstructure mechanical rheological and thermal properties of silane modified EPDM was studied A comparison with un modified matrix was also considered The grafting reaction confirmed by Fourier transform infrared spectroscopy FT IR The state of dispersion of the fillers in the polymer matrix was evaluated through scanning electron microscopy SEM and atomic force microscopy AFM The rheological characteristics were studied by rubber process analyzer RPA and dynamic properties were also investigated by dynamic mechanical thermal analysis DMTA In addition the mechanical measurement was also done Moreover the thermal behavior of VTMS modified EPDM MWCNT composite were studied by thermogravimetric analysis TGA The results obtained show that the cure time t and scorch time t were decreased while maximum torque M and minimum torque M of the modified composites were increased with increasing MWCNT concentration this investigation also showed that VTMS grafted onto the EPDM surface improved the dispersion of MWCNTs in matrix The rheological properties of composites such as storage modulus G and complex viscosity was increased due to increasing MWCNT content In addition it was found that due to increasing the amount of MWCNT composite exhibited superior modulus tensile strength and hardness whereas lower elongation at break compared to pure and un modified polymers It showed that the thermal stability of VTMS modified EPDM MWCNT was improved Dynamic mechanical thermal studies reveal a strong rubber filler interaction in the composite which is manifested in the lowering of tan at the glass transition temperature These finding confirmed the improved interfacial interactions arising from covalent bond between modified EPDM and functional groups of MWCNTs Keywords Composite EPDM MWCNT rheological characteristic mechanical properties PDF created with pdfFactory trial version www pdffactory com

خادمه مولوي، فاطمه

تهيه كامپوزيت EPDM/MWCNT با خواص مكانيكي-رئولوژيكي بهبود يافته از طريق اصلاح سيلاني پليمر در غلظت هاي مختلف نانو لوله كربن

چند ديواره