Nanocomposites of Polypropylene and Halloysite Nanotubes Prepared by a Novel Vane Mixer

Abstract

Halloysite nanotubes (HNTs) were used to prepare polypropylene (PP) nanocomposites through a novel vane mixer. The effects of melt blend time and halloysite content on properties of composites were investigated. SEM analysis was performed to show that HNTs were well dispersed in PP matrix with the increase of mixing time. DSC showed both the degree of crystallinity and crystallization temperature increased due to the introduction of HNTs into PP, which indicating a potential nucleation effect induced by the nanotubes. TGA illustrated that the presence of HNTs had two opposite effects on the thermal behavior. A surface catalytic action of the halloysite speeded up thermal degradation of PP. However, this effect was reduced with improved HNTs dispersion. Rheological investigations revealed that rheological properties were significantly increased by the addition of low fraction of halloysite to PP. The 2 wt% HNTs nanocomposites reached maximum tensile strength because HNTs dispersed evenly in PP.

“Tree-Ring” Patterns of Halloysite Nanotubes by Agitation-Assisted Assembly for Guiding Cell Alignment

“…The storage and loss moduli of the HNT dispersions with different concentrations as a function of the angular frequency are presented in Figure D,E. Generally, the storage and loss moduli increased with the HNT concentration, which fit well for the model of a rodlike particle suspension. − According to the viscoelastic theory, it is believed that the storage and loss moduli of the suspension increase with an increase of the frequency because of the formation of a network of solid particles. , The shear viscosities of HNT dispersions with different concentrations as a function of the shear rate are shown in Figure F. Evidently, a strong shear-thinning effect of the HNT dispersion was found at low shear rate, which could maintain great dispersibility under a shear force and thus would form a regular HNT pattern.…”

“…44−46 According to the viscoelastic theory, it is believed that the storage and loss moduli of the suspension increase with an increase of the frequency because of the formation of a network of solid particles. 47,48 The shear viscosities of HNT dispersions with different concentrations as a function of the shear rate are shown in Figure 2F. Evidently, a strong shear-thinning effect of the HNT dispersion was found at low shear rate, which could maintain great dispersibility under a shear force and thus would form a regular HNT pattern.…”

Rheological Percolation of Cellulose Nanocrystals in Biodegradable Poly(butylene succinate) Nanocomposites: A Novel Approach for Tailoring the Mechanical and Hydrolytic Properties

“…cosity shows a sharp decrease even at low frequencies. 31,32 In addition, η' increases noticeably over the entire frequency range of observation. Similarly, incorporation of CNC results in a sharp increase in G' (Figure 5(b)).…”