Tailored Nanocomposites of Polypropylene with Layered Silicates

Abstract

The melt rheological properties of layered silicate nanocomposites with maleic anhydride (MA) functionalized polypropylene are contrasted to those based on ammonium-terminated polypropylene. While the MA functionalized PP based nanocomposites exhibit solid-like linear viscoelastic behavior, consistent with the formation of a long-lived percolated nanoparticle network, the single-end ammonium functionalized PP based nanocomposites demonstrated liquid-like behavior at comparable montmorillonite concentrations. The differences in the linear viscoelasticity are attributed to the presence of bridging interactions in MA functionalized nanocomposites. Further, the transient shear stress of the MA functionalized nanocomposites in start-up of steady shear is a function of the shear strain alone, and the steady shear response is consistent with that of non-Brownian systems. The weak dependence of the steady first normal stress difference on the steady shear stress suggests that the polymer chain mediated silicate network contributes to such unique flow behavior.

Influence of hard segment content and nature on polyurethane/multiwalled carbon nanotube composites

“…The concept of creating both structural and functional multi-nanophase composites with improved performance is currently under development in a wide variety of metallic, ceramic and polymeric matrices, although the emphasis to date has been on polymeric systems [1][2][3]. By introducing carbon nanotubes (CNT) into a polymer matrix, many properties can be improved at once, including mechanical [4,5], thermo-mechanical [6], electrical [7,8], thermal [9,10], chemical [11] and optical properties [12].…”

Enhancing damping properties of epoxy resins using silicone macromolecule intercalated montmorillonite clay

“…A tiny fluctuation of Tg was exhibited among the epoxy-nanocomposites with different content of LVHS-OMMT in Fig.13. It has been reported that the addition of the organoclay can increase Tg by strengthening the polymer network by the polymer absorbed on the surface of the filler (increase of entanglements) [19][20] , while the free flexible silicone macromolecules can decrease it. These two factors, which provide the opposite effect, may account for the tiny fluctuation in Tg.…”

Toughened elastomer/polyhedral oligomeric silsesquioxane (POSS)‐intercalated rectorite nanocomposites: Preparation, microstructure, and mechanical properties

“…Hence, polymer/layered silicate nanocomposites have been attracting intense interest in recent years [11][12][13][14][15]. As a type of regularly interstratified clay mineral, rectorite (REC) is made of alternative dioctahedral mica-like layer and dioctahedral smectite-like layer at a 1:1 ratio.…”