Experimental and Monte Carlo simulation studies on percolation behaviour of a shape memory polyurethane carbon black nanocomposite

Abstract

Electro-active shape memory polymer nanocomposite from polyurethane matrix with carbon black fillers was synthesized and characterised for its electrical properties. The polyurethane matrix possesses high transition temperature, which enables it to be a candidate for high temperature applications. The carbon nanoparticle content was varied with conductivity measured at each instance, and a percolation threshold value of 6% was observed experimentally. The conductivity phenomenon was studied using Monte Carlo simulation approach on a pseudo random model of the system, developed using constrained optimization by linear approximations algorithm in visual C language platform. The probability of three dimensional network formations of carbon particles was evaluated for varying filler loading and percolation threshold of 6.2% was obtained from the model. The conductive networks formed have resulted in multiple electron paths, generating volumetric heating of the system while connected with a known power supply. This joule heating was used as stimuli for activating the shape memory behaviour by passage of electric current. High shape recovery efficiency (>95%) observed with faster recovery time (25 s), along with high transition temperature (85°) can help to qualify the system for space applications.

Selective entanglement coupling of nanoparticles in polymer nanocomposite with high shape recovery stress

“…On the other hand, the topological entanglement of nanoparticle and macromolecular chain is then decreased with a further increase in concentration of nanoparticle from 3% to 5%, resulting in relaxation motions accelerated. These analytical and experimental results are following the percolation rule of nanoparticles in the nanocomposites [21].…”

“…A micromechanical model was previously utilized to study the interphase influences on the mechanical behavior of SMP nanocomposite, and the environmental conditions were considered in the modelling process [19,20]. Monte Carlo simulation was also used to study the percolation behavior of SMP nanocomposite reinforced by carbon black [21].…”

Structural-modelling and experimental validation of percolation threshold for nanotube-polyurethane shape memory system

“…The reduction in the resistivity is attributed to the increased contacts of the MWNT or the conducting networks formed between them ultimately cause a reduction in resistivity. The same can be discerned in the model where the particle closeness is evaluated for a percolation network [38][39][40].…”

Effect of nanofillers on polyurethane/polystyrene matrix nanocomposites: Characteristics and forthcoming developments

“…80 Nanofiller additives have been used in the polyurethanes to enhance the shape memory properties. 81 Various nanofillers filled in the polyurethanes, to enhance the thermal, mechanical, electrical, and shape memory, include carbon nanotube, 82,83 graphene, 84,85 carbon black, 86,87 nanoclay, and inorganic nanoparticles. 88 Table 3 lists the electrical conductivity and electric field-triggered or electro-active shape recovery properties of the PU/PS, PU/PS-NO 2 , and PU/PS-NH 2 .…”