Preparation and characterization of CNTs/UHMWPE nanocomposites via a novel mixer under synergy of ultrasonic wave and extensional deformation

Abstract

In this work, design and development of a new melt mixing method and corresponding mixer for polymer materials were reported. Effects of ultrasonic power and sonication time on the carbon nanotubes (CNTs) filled ultra high molecular weight polyethylene (UHMWPE) nanocomposites were experimentally studied. Transmission Electron Microscopy images showed that homogeneous dispersion of CNTs in intractable UHMWPE matrix is successfully realized due to the synergetic effect of ultrasonic wave and extensional deformation without any aid of other additives or solvents. Differential scanning calorimetry results revealed an increase in crystallinity and crystallization rate due to the finer dispersion of the CNTs in the matrix which act as nucleating point. Composites' complex viscosity and storage modulus decreased sharply at first and then leveled off with the increase of sonication time or the ultrasonic power. The thermal stability and the tensile strength of the CNTs/UHMWPE nanocomposites improved by using this novel mixing method. This is the first method that combined the ultrasonic wave and the extensional deformation in which the elongation rate, sonication time and ultrasonic power can be adjusted simultaneously during mixing. The novel mixer offers several advantages such as environment-friendly, high mixing efficiency, self-cleaning and wide adaptability to materials.

Trends on Synthesis of Polymeric Nanocomposites Based on Green Chemistry

“…The ultrasonically treated PNCs showed an increase in the viscosity and storage modulus which indirectly indicates high dispersion of MWCNTs even to concentrations of up to 10 wt. [47] Likewise, There are extruders where the extensional deformation of the flow is combined with the controlled sonication to create a synergistic effect in the compounding of PNCs, [48] as well as extruders with the ability to induce an ultrasonic treatment during the injection of mechanical test specimens [49]. Along with the works mentioned above related with innovations in extrusion and injection of PNCs, new processes and equipment have also been introduced to sonicate PNCs/ epoxy resin formulations.…”

Homogeneous dispersion of multiwalled carbon nanotubes via in situ bubble stretching and synergistic cyclic volume stretching for conductive LDPE/MWCNTs nanocomposites

“…The characteristic of interlaced divergent and convergent flow of melt in the cavity of the vane mixer was utilized to achieve the effect of repeated bubble stretching. The vane mixing device is a new type of nonscrew plasticizing processing equipment based on extensional deformation, and the schematic of its mixing unit is shown in Fig. .…”

“…Here, we reported a method for preparing LDPE/MWCNTs nanocomposites that achieved better dispersion of one‐dimensional nanofillers. This novel method is solvent free and uses no surface modification of the fillers . And this new processing method will provide a double stretching effect in order to promote the dispersion of MWCNTs.…”

In-Situ Bubble Stretching Assisted Melt Extrusion for the Preparation of HDPE/UHMWPE/CF Composites

“…In addition, it is an effective way to improve the mixing efficiency and performance by superimposing external force field onto elongation flow or shear flow. Yin [30] designed a novel mixing device in which ultrasonic vibration synergized with extensional deformation acts on the melts. The morphology results showed that CNTs dispersed homogeneously in intractable UHMWPE matrix without any aid of additives or solvents.…”