Preparation and characterization of carbon nanotube filled poly (2-hydroxyethylmethacrylate) nanocomposites

Abstract

Poly(2-hydroxyethylmethacrylate) (PHEMA)/multiwalled carbon nanotubes (MWNTs) nanocomposites were prepared by solvent casting using dimethyl formamide (DMF) solvent via sonication process. Effect of addition of MWNTs on the properties of nanocomposites was investigated at different nanofiller contents. Uniform dispersion and distrubution of nanotubes in PHEMA matrix is obtained within the studied composition range. The electrical resistivity, dielectric permittivity and the loss factor of dry PHEMA and PHEMA/MWNT nanocomposites were studied by varying the MWNT concentration in the frequency range of 30 Hz to 1 MHz. The obtained results indicated that the addition MWNTs to PHEMA matrix decreases the electrical resistivity and increases the dielectric constant at low dielectric loss. The thermal properties of the PHEMA/MWNT nanocomposites were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The thermal behavior of these nanocomposites was also compared with PHEMA homopolymer. The glass transition temperature (T g ) of PHEMA homopolymer was found to increase with nanotube concentration. Experimental results also demonstrated that the incorporation of the MWNTs into the PHEMA matrix not only enhanced the mechanical property but also increased and the thermal stability of the PHEMA/MWNT nanocomposites increases with increase in MWNT concentration.

Qualifying Dispersion and Distribution of Carbon Nanotubes in Polyamide Matrix during Melt-Mixing by Flow Simulation

“…At a given time, in addition to solve the continuity and Navier-Stokes equations, the solver linked to Matlab calculates the new position of the points by using a Runge Kutta (order 4) scheme. The distributive capability of the flow can then be characterized by the length stretch method reported by Tao and Manas-Zloczower 32 , which is defined as the ratio (l) of the distance between two points at time t (d) to its initial value at t 0 (d 0 ) ( 15): (15) The distributive capability can also be characterized using the Lyapunov exponent which measures the divergence of the trajectories of two points infinitely close from each other at the initial time t 0 . At each time and for each point (located at time t by  X(t) ), the local Lyapunov exponent λ e (  X(t)) reflecting the instantaneous expansion rate is calculated by ( 16): (16) where represents the mean value of the distances between the two nearest points at a time t, and this same mean value at a time t + dt (dt is the time step used in the simulation).…”

“…Controlling the nanocomposite elaboration process is thus crucial. Very good results were achieved by melt compounding in a twin-screw extruder [3][4][5][6] for different polymer matrices and filler contents [7][8][9][10][11][12][13][14][15] .…”

Enhancement in mechanical properties and conductivity of modified epoxy resin composites

“…Since the first observation of multiwalled carbon nanotubes (MWCNTs) by Iijima, 1 a lot of researches in the field of carbon nanotubes/polymer nanocomposites have made progress due to their excellent mechanical and electrical properties. 2 –4 On the one hand, MWCNT has a unique atomic structure and can achieve very high aspect ratios because of their diameters in the range of a few nanometers with lengths of several hundred nanometers. In light of these properties, MWCNTs have attracted more and more attention and dispersed in a wide range of matrices including polymers, resins, metal to enhance the mechanical, electronic properties, and heat resistance.…”

“…In light of these properties, MWCNTs have attracted more and more attention and dispersed in a wide range of matrices including polymers, resins, metal to enhance the mechanical, electronic properties, and heat resistance. 3 On the other hand, the surface of MWCNTs shows a chemical inertness which dramatically limits the application scope of the MWCNTs. In order to solve the above problems, we can deal with the MWCNTs by the mixed acids.…”

Preparation and Characterization of Poly(2-Hydroxyethyl Methacrylate) and Castor Oil Based Uralkyds Interpenetrating Polymer Networks

“…Though voluminous literature is available on modified castor oil polyurethane, the study of IPNs of modified castor oil polyurethane has not been paid due attention. As a part of our studies on polymeric materials [16][17][18][19] , in this article we report on the miscibility of a new blend system of Poly[2-Hydroxyethylmethacrylate] (PHEMA) and castor oil based uralkyds (UA).…”