مدل سازي و مطالعه رئولوژي و ريخت شناسي آلياژهاي PA6/ABS و اثر نانورس بر خواص حرارتي آن

چكيده انگليسي :

Modeling and Study on Rheology and Morphology of ABS PA6 Blends and the Role of Nanoclay on Thermal Properties of the Blend Mahbobeh Aminjafari m aminjafari@ce iut ac ir Date of Submission 2011 05 28 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisors Morteza Sadeghi m sadeghi@cc iut ac ir Mahmood Masumi mmasoomi@cc iut ac irAbstract In this study rheological and morphological properties of incompatibilized polyamide 6 acrylonitrilebutadiene styrene blend and their relationship was investigated Also the effect of nanoclay on heatresistance and flammability of the blends was studied The blends were prepared with compositions of0 10 25 50 75 90 and 100 weight polyamide 6 and their nanocomposites with 3 nanoclay All themixtures were prepared in same conditions in a twin screw extruder 240 c and rotation speed of 60 rpm Linear viscoelastic properties rheology morphology of all blends with heat resistance of nanocompositesand their flammability have been investigated by using vibrational dynamic rheometer RMS scanningelectron microscopy SEM termogravimetric analysis TGA and limited oxygen index LOI experiments respectively Rheological behavior of polyamide 6 was newtonian Due to existence of rubberphase in structure of acrylonitrile butadiene styrene it has a three dimentional network which makes a yieldstress in acrylonitrile butadiene styrene that causes a platue in low frequencies region in its storagemodulus frequency plot This behavior is also observed in all rich acrylonitrile butadiene styrene blends Viscosity storage modulus and loss modulus of acrylonitrile butadiene styrene was larger than polyamide 6through all frequency ranges and it was decreased with adding polyamide 6 Comparison between complexviscosities of blends with additive rule showed a negative deviation of additive rule in all compositions thisdeviation in processing conditions implies to interlayer slippage behavior in the components interfacewhich show emulsionlike behavior is prominent Increasing elasticity of rich polyamide 6 blends is morepronounced than rich acrylonitrile butadiene styrene blends Because polyamide 6 get more orientationthan acrylonitrile butadiene styrene due to shear rate Interfacial tension of acrylonitrile butadienestyrene polyamide 6 was calculated in accordance to harmonic equation Then rheological behavior of theblend was fitted to some rheological models Fitting to Palierne model was good for polyamide 6 richblend containing 75 wt PA6 but not for acrylonitrile butadiene styrene rich blend containing 75wt ABS Because Palierne model doesn t predict yield stress of ABS Also complex modulus of the blendswas fitted to Zener model This fitting was done for all blends and had good results especially forpolyamide 6 rich blends through all frequency range So a unique model was obtained for this blend getscomplex modulus of blends just versus frequency and component percentage without requiring anyunknown parameter Morphology studies shows blend with 50wt polyamide 6 have cocontinuousmorphology and other compositions have dispersed matrix structure Dispersed phase particles size waspredicted by Teilor model and it was in good agreement with morphological results In the second part ofthis study heat resistance and flammability of polyamide 6 75wt and polyamide 6 25wt was comparedto their nanocomposites having 3wt nanoclay The results showed heat resistance of nanocompositesimproved in comparison by neat blends Especially this improvement is more pronounced for polyamide 625wt nanocomposite Because this nanocomposite have more acrylonitrile butadiene content thanpolyamide 6 75wt and acrylonitrile butadiene styrene which have less heat resistance than polyamide 6

امين جعفري، محبوبه

مدل سازي و مطالعه رئولوژي و ريخت شناسي آلياژهاي PA6/ABS و اثر نانورس بر خواص حرارتي آن

آلياژ پليمري , آلياژ امتزاج ناپذير , پلي آميد , اكريلونيتريل بوتادين استئايرن , نانو كامپوزيت , اشتغال پذيري