Effect of multiwall carbon nanotubes on the phase separation of concentrated blends of poly[(α-methyl styrene)-co-acrylonitrile] and poly(methyl methacrylate) as studied by melt rheology and conductivity spectroscopy

Abstract

• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publicationCitation for published version (APA): Bose, S., Cardinaels, R. M., Özdilek, C., Leys, J., Seo, J. W., Wübbenhorst, M., & Moldenaers, P. (2014). Effect of multiwall carbon nanotubes on the phase separation of concentrated blends of poly[(-methyl styrene)-coacrylonitrile] and poly(methyl methacrylate) as studied by melt rheology and conductivity spectroscopy. European Polymer Journal, 53, 253-269. DOI: 10.1016/j.eurpolymj.2014.01.030 General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. resulted in a selective thermodynamically driven localization of both types of MWNTs in the PαMSAN phase whereas they were randomly distributed in the mono-phasic materials. Hence, a percolative MWNT network was formed at much lower concentrations as compared to those needed for percolation in the blend components. However, the significant changes in viscosity and elasticity of the blend components, brought about by the MWNTs, can also affect morphology development. This way, effective percolation in the blends can be hindered, as was observed for the 60/40 blend with polyethylene coated MWNTs (PE-MWNTs). Finally, a dramatic transition from an insulating one-phasic material at room temperature to a highly conductive material in the melt was induced by the phase separation.

Morphology evolution, conductive and viscoelastic behaviors of chemically reduced graphene oxide filled poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) nanocomposites during annealing

“…5b). The localization of CRGO in the SAN-rich phase for the phase-separated PMMA/SAN system is similar with those of RGO and MWCNTs in the PMSAN phase for PMMA/PMSAN blend [32,63] . In an immiscible or partial miscible blend, the minimization of the interfacial energy is the thermodynamic driving force for the filler to localize in a specific phase or at the interface [64] .…”

“…[69] . The initial increase of G arises from the formation of new co-continuous phase interface at the early stage of SD and the following decrease of G may be attributed to the decrease of interfacial area induced by the domain coalescence and the morphology transition from percolation to droplet of SAN-rich domain in the late stage of phase separation due to the excess of interfacial energy [63,70] . Figure 7(b) shows the blend morphology after being annealed for 10 h at 180 C and affirms the breakup of SAN-rich (dark region) phase network.…”

Electrical and melt rheological characterization of PC and co‐continuous PC/SAN blends filled with CNTs: Relationship between melt‐mixing parameters, filler dispersion, and filler aspect ratio

“…Adding carbon fillers to polymers changes their melt rheological behavior. In structure sensitive frequency dependent oscillatory tests—particularly at low measurement frequencies—an increase in the complex melt viscosity and the storage and loss moduli can be observed with increasing filler content . At constant filler level, the degree of increase is mainly dependent on the state of dispersion of the nanoparticles, which reflects the filler–polymer and filler–filler interactions.…”

Spherical nanoparticle effects on the lower critical solution temperature phase behavior of poly(ε‐caprolactone)/poly(styrene‐co‐acrylonitrile) blends: Separation of thermodynamic aspects from kinetics

“…Along with the theoretical works, the effects of nanofillers on the phase behavior of polymer blends have been critically investigated by using different experimental approaches . Small‐angle light scattering (SALS) and optical microscopy have been widely applied to determine the phase‐transition points of binary polymer blends and filled polymer mixtures .…”

“…The refractive indices of polymers, film transparency, and thickness are the most important parameters in SALS and optical microscopy measurements that can affect the validity of the results . Following the linear viscoelastic responses over the phase transition is one of the well‐established strategies to study the phase behavior of polymer mixtures, which is less affected by the film transparency and thickness . Because of the high sensitivity to the chain repetition time, diffusion, and interfacial viscoelasticity, the rheological measurements can correlate the linear viscoelastic responses of polymer mixtures with subtle structural changes during phase separation process and detect the phase transition in rather early stages .…”