Mechanical properties and morphology of polypropylene‐calcium carbonate nanocomposites prepared by dynamic packing injection molding

Abstract

In this article, dynamic packing injection molding (DPIM) technology was used to prepare injection samples of Polypropylene-Calcium Carbonate (PP/CaCO 3 ) nanocomposites. Through DPIM, the mechanical properties of PP/nano-CaCO 3 samples were improved significantly. Compared with conventional injection molding (CIM), the enhancement of the tensile strength and impact strength of the samples molded by DPIM was 39 and 144%, respectively. In addition, the tensile strength and impact strength of the PP/nano-CaCO 3 composites molded by DPIM increase by 21 and 514%, respectively compared with those of pure PP through CIM. According to the SEM, WAXD, DSC measurement, it could be found that a much better dispersion of nano-CaCO 3 in samples was achieved by DPIM. Moreover, ccrystal is found in the shear layer of the DPIM samples. The crystallinity of PP matrix in DPIM sample increases by 22.76% compared with that of conventional sample. The improvement of mechanical properties of PP/nano-CaCO 3 composites prepared by DPIM attributes to the even distribution of nanoCaCO 3 particles and the morphology change of PP matrix under the influence of dynamic shear stress.

CaCO3–Polymer Nanocomposite Prepared with Supercritical CO2

“…The overall percentage of CaCO 3 in the nanocomposite was estimated to be 57.3 wt%; that is, the CaCO 3 content was high. Producing nanocomposites containing large amounts of inorganic materials is difficult via conventional mixing processes [14].…”

“…The TGA result showed that the content of CaCO 3 in the whole sample was relatively high. Even though CaCO 3 nanocomposites have previously been synthesized [14,19,20], synthesizing nanocomposites with a high CaCO 3 content remains challenging. For example, in a previous synthesis of CaCO 3 nanocomposites, CaCO 3 particles with dimensions of several tens of nanometers, synthesized in advance, were mixed with polymers, but when high concentrations of these CaCO 3 particles were mixed with the polymers, CaCO 3 aggregated [21].…”

Hydrothermal Hot Pressing of CaCO3‐Chitosan Composites with High CaCO3 Content

“…e overall percentages of CaCO 3 in the composites were estimated to be 93.0, 93.2, and 93.5 wt.% for discs fabricated from the CaCO 3 -chitosan composites prepared at 4 and 95°C and the scallop shell disc, respectively; that is, the CaCO 3 contents were high. is is noteworthy because producing nanocomposites containing large amounts of inorganic materials is difficult via conventional mixing processes [13].…”

Morphology Control Technologies of Polymeric Materials During Processing

“…In addition to an enhanced degree of orientation, Yang et al also observed well‐defined nanohybrid shish–kebab entities, in which CNTs acted as shish while HDPE lamellae acted as kebab, within the oriented zone of HDPE/CNTs composites prepared by OPIM. Gao et al prepared PP/CaCO 3 (9 wt%) nanocomposites utilizing OPIM technology and investigated the effect of oscillation pressure on the mechanical properties of PP/CaCO 3 and PP samples. The improvement of mechanical performances is shown in Table .…”