Effect of nanofillers on the phase separation and rheological properties of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) blends

Abstract

International audienceThe viscoelastic characteristics of the blends of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) (PMMA/SAN) were investigated at various temperatures below, near, and above the phase separation temperature. The investigated polymer system is characterized by a lower critical solution temperature. Rheological behavior of the blends in the region of a phase separation was compared with change of the light scattering intensity. The presence of nanofillers in the blend results in that the phase separation occurs at a higher temperature. At the isothermal conditions, the phase separation begins earlier and proceeds with a higher rate as compared with the same blend without filler. The results of the study show the considerable change of the viscoelastic characteristics of PMMA/SAN when the polymer system passes from the homogeneous state to the heterogeneous one. Such characteristics as the dependence of the storage modulus (G (')) on the loss modulus (G (aEuro3)), the dependence of the loss viscosity (eta (aEuro3)) on the dynamic viscosity (eta (')), the dependences of the complex viscosity (eta*), and the free volume fraction (f) on the blend composition are the most sensitive to the phase separation. The phase separation affects the characteristics G (')(omega), where omega is the frequency only in a low-frequency range. Temperatures of phase separation were estimated using dependence G (')(T) at omega, which is the constant in the range of low frequencie

Effect of Thermally Reduced Graphene Sheets on the Phase Behavior, Morphology, and Electrical Conductivity in Poly[(α-methyl styrene)-co-(acrylonitrile)/poly(methyl-methacrylate) Blends

“…Nanoclay was also observed to induce phase separation in PMMA/SAN blends . On the contrary, Shumsky et al reported a delay in phase separation in presence of nanoclay in the same system (PMMA/SAN). Hence, the surface chemistry, the characteristics, the concentration and the positioning of the nanoparticles play a significant role in influencing the thermodynamics of phase separation.…”

Structuration, selective dispersion and compatibilizing effect of (nano)fillers in polymer blends

“…Hence, the effect of SiO 2 on the phase separation behavior of PMMA/SAN blend obviously depends on the composition of the blend matrix. More recently, Shumsky et al [31] investigated the viscoelastic characteristics of the blends of PMMA/SAN blends at various temperatures below, near, and above the phase separation temperature. The presence of non spherical nanofillers (natural montmorillonite Cloisite ® Na + (ClNa), montmorillonite Cloisite ® 30B (C30B) modified with triple ammonium salt) in the blend results in the change of the interactions between the components at the interphase that promote the change of the free mixing energy.…”

Unusual Phase Separation Kinetics in Poly(Methyl Methacrylate)/Poly(Styrene-co-Acrylonitrile) (PMMA/SAN) Blends with PMMA of Different Molecular Weights

“…Various factors that influence the phase behavior of polymer blends, such as shear flow [7][8][9], filler [10][11][12][13][14], composition [15][16][17], viscosity [18], thickness of blend film [19] and molecular weight [1,[20][21][22], have been investigated. The relative molecular weights of the polymers is regarded as one of the most important factors which control the thermodynamics, kinetics and morphology of polymer blends.…”