An experimental study on the micro- and nanocellular foaming of polystyrene/poly(methyl methacrylate) blend composites

Abstract

<jats:title>Abstract</jats:title> <jats:p>Polystyrene/poly(methyl methacrylate) (PS/PMMA) blends in 80:20, 50:50, and 20:80 ratios with and without calcium carbonate nanoparticles were prepared. <jats:italic>n</jats:italic>-Pentane was then used to foam the samples in an autoclave. After the diffusion of <jats:italic>n</jats:italic>-pentane gas into the polymer matrix, the samples and the gas were simultaneously cooled to obtain the liquid <jats:italic>n</jats:italic>-pentane phase. Phase change to liquid provided the required pressure drop for cell nucleation and consequent cell growth. The solubility of <jats:italic>n</jats:italic>-pentane in the samples was measured. Liquid <jats:italic>n</jats:italic>-pentane trapped inside created micro- and nanopores, forming a foam with closed cells. Experiments were carried out in different compositions of the materials, with and without nanoparticles, and the cell morphologies were characterized. The results of this work show that nanocellular structures can be achieved when calcium carbonate nanoparticles are added to PS/PMMA blends.</jats:p>

The relationship between cellular microstructure and the mechanical properties of styrene/methyl methacrylate copolymer‐silica nanocomposite foams prepared by a supercritical CO2 blowing agent

“…[34][35][36][37][38] The diffusivity and solubility of CO 2 in PMMA and PS matrices are increased by enhancement of pressure and reduction of temperature, respectively. 9,39 Jahani et al 40 investigated the foaming of PMMA/PS blends by n-pentane gas as a physical foaming agent, in the presence of calcium carbonate nanoparticles. They observed that the addition of calcium carbonate nanoparticles enhanced the morphological and mechanical properties of the final foams.…”

Effect of the Molecular Structure of TPU on the Cellular Structure of Nanocellular Polymers Based on PMMA/TPU Blends

“…The nucleating agent increases the nucleation density to the values required to reduce the cell size to the nanoscale (higher than 10 13 nuclei/cm 3 ), allowing to produce nanocellular polymers. In the last years, several studies were conducted focusing on the effect of nucleating species in the fabrication of nanocellular polymers, such as nanoparticles [ 17 , 18 , 19 , 20 ] or an immiscible polymeric second phase [ 21 , 22 ]. For instance, Liu et al [ 23 ] synthesize silica nanoparticles with different surface roughness to enhance the nucleation of poly(methyl-methacrylate) PMMA.…”

The diffusivity modeling of different gases in acrylonitrile butadiene styrene (ABS)

“…26 Also we investigated the foaming process of PS/PMMA blends and copolymers by our designed bath system and the cellular structures of produced polymer foams were fully illustrated. 27–30 Most of the models developed so far have been expressed in a form of an exponential function of either the free volume or the free volume fraction. In order to apply the models to estimating the diffusion of gas in a polymer, one must estimate the specific free volume of the polymer/gas mixture and to determine model parameters, such as the pre-exponential coefficient, an activated energy, etc.…”