Effects of nano- and micro-fillers and processing parameters on injection-molded microcellular composites

Abstract

The effects of submicron core-shell rubber (CSR) particles, nanoclay fillers, and molding parameters on the mechanical properties and cell structure of injectionmolded microcellular polyamide-6 (PA6) composites were studied. The experimental results of PA6 nanocomposites with 5.0 and 7.5 wt% nanoclay loadings and of CSR-modified PA6 composites with 0.5 and 3.1 wt% CSR loadings were compared to their neat resin counterparts. This study found that nanoclay was more efficient in promoting a smaller cell size, larger cell density, and higher tensile strength for microcellular injection molding parts. A higher nanoclay loading led to more brittle behavior for microcellular parts. It was found that a proper amount of CSR particles could be added to the microcellular injection-molded PA6 to reduce the cell size, increase the cell density, and enhance the toughness of the molded part. However, CSR particles were less effective cell nucleation agents as compared to nanoclay for producing desirable cell structures, and a higher CSR loading was found to have diminishing effects on the process and on the properties of the parts. POLYM. ENG. SCI., 45:773-788, 2005.

Nanofibrillated cellulose (NFC) reinforced polyvinyl alcohol (PVOH) nanocomposites: properties, solubility of carbon dioxide, and foaming

“…In addition, cell size in the PVOH/NFC nanocomposites generally decreased with increasing NFC content and the cell density increased, suggesting that NFC nucleates cells. These results agree with findings from the literature on other types of nanocomposites Yuan et al 2005;. It should be pointed out that a few larger cells observed in the PVOH/NFC nanocomposites were likely formed by evaporated vapor from the NFC instead of CO 2 , thus resulting in a large error bar.…”

Open‐Pore Biodegradable Foams Prepared via Gas Foaming and Microparticulate Templating

“…This restricts the expansion of cells, [11] and is also related to the feasible nucleating effect of the filler. [51] By the further increase of NaCl to 70 wt.-% ( Figure 3d) the foams showed a progressive decrease of the pore size and the pores created by the gas foaming and microparticle leaching became indistinguishable. These results are in agreement with the curves of F and D C plotted against NaCl concentration in Figure 4a and the pore-size distributions for different NaCl concentrations shown in Figure 4b.…”

Use of nanoparticles for improving the foaming behaviors of linear PP

“…9 Recently, nanoclay particles have also been used in the polymer nanocomposite foaming process, serving as efficient nucleating agents that help to decrease the foam cell size and increase the foam cell density. [14][15][16][17][18] Previously, micrometer-size fillers were employed to this end. [19][20][21] However, what distinguishes clay nanoparticles from traditional microfillers is that the role of nanoparticles in polymer foaming may not be simply limited to cell nucleation, but may also encompass significant functions that promote polymer foamability and affect foam morphologies.…”