Improvement of the dispersity of micro‐nano particles for PP/PVC composites using gas‐assisted dispersion in a controlled foaming process

Abstract

Polyvinyl chloride (PVC) and nanosilicon dioxide (nano‐SiO2) were blended with neat polypropylene (PP) to improve its flame retardancy and cellular foam structure, and the dispersal effects of PVC and nano‐SiO2 and the foaming effect of the PP/PVC composites were investigated. PP/PVC samples with different compositions and foaming degrees were first fabricated by conventional injection molding with and without a blowing agent. Tensile testing, differential scanning calorimetry, scanning electron microscopy, limiting oxygen index testing, and vertical burn testing were used to study the mechanical properties, thermal features, microstructures, and flame‐retardant properties of the molded samples, and the samples with different degrees of foaming were compared. The results suggest that the foaming process facilitates the dispersion of PVC and nano‐SiO2, while the presence of PVC and nano‐SiO2 improves the foamability of PP. A method for a gas‐assisted dispersion technology to control the foaming process was hence proposed. Considering that the mechanical properties of PP/PVC could be retained with satisfactory flame retardancy and weight loss, convenient processing, and low‐cost materials; the technology presented can be directly applied for lightweight engineering and the manufacture of fire‐resistant material and can act as a reference for other micro‐nano processing involving the dispersion of particles. POLYM. ENG. SCI., 60:524–534, 2020. © 2019 Society of Plastics Engineers

Effect of in situ fibrillation on polyethylene/poly(ethylene terephthalate)/multiwalled carbon nanotube electromagnetic shielding foams

“…[ 45,46 ] In this article, 0.5 wt% weight reduction is applied, we aim at using uniform cell size and distribution to maintain even distribution of MWCNT, thus promote high EMI SE with low filler content. [ 47 ]…”

Effects of Ultrasonication Time on the Properties of Polyvinyl Alcohol/Sodium Carboxymethyl Cellulose/Nano-ZnO/Multilayer Graphene Nanoplatelet Composite Films

“…This behavior was ascribed to the strong adsorption of graphene, which may limit the movement of PVA/CMC molecular chains to increase tensile strength. Moreover, graphene can increase compatibility between ZnO NPs and PVA/CMC and provide the effect of particle reinforcement [ 51 ]. Finally, the beneficial effect of x GnP can also be ascribed to the high mechanical strength of graphene sheets [ 52 ].…”

“…Pure PVA/CMC films featured a maximum tensile strength of 45.50 ± 3.18 MPa and a maximum Young’s modulus of 33.95 ± 2.93 MPa, which was hardly affected by the incorporation of only ZnO NPs or graphene. This finding was ascribed to the poor compatibility between ZnO NPs or x GnP and PVC/CMC, which resulted in weak interfacial adhesion between the two phases, and hence in the easy initiation and propagation of cracking at the corresponding interface [ 51 ]. However, this impact was small.…”

Microwave foaming of carbon dioxide saturated poly lactic acid

“…Polymer foams with micro‐ and nano‐sized pores have gained significant attention in the recent past as they find numerous applications such as in filtration, energy absorption, thermal insulation, catalysis, and tissue engineering scaffolds. [ 1–7 ] The current techniques to fabricate polymer foams include particulate leaching, [ 8,9 ] thermal induced phase transition, [ 10,11 ] gas foaming, [ 12 ] block co‐polymers, [ 13 ] immiscible polymer blending, [ 14 ] and solid‐state foaming. [ 15,16 ] However, majority of these techniques result in thin films with low porosity and do not offer control over the resulting pore morphology.…”