Study on the viscosity of polypropylene composites filled with different size and size distribution CaCO₃

Abstract

Two kinds of different size calcium carbonates are blended and filled into polypropylene in 30 wt%. The melting viscosity of PP composites samples is measured by capillary extrusion rheometer at 2308C. The results show that the melt viscosity of PP composites evidently decreased when that was filled with the blending 325 and 1,500 mesh CaCO 3 and the 1,500 mesh proportion in fillers was from 20 to 60 wt%. The viscosity in the low shear velocity decreased more than that in the high shear velocity. The shear viscosity of single filler and filler samples with the size distribution at the different temperature was studied by capillary extrusion rheometer. The results show that the flow activation energy and the flow activation entropy of composites filled with the size distribution filler increased. The change of the flow activation entropy and the model of the efficient arrangement of the structure are used to explain the phenomenon in melting viscosity decrease of PP filled with the size distribution fillers. A structural model of composites that filled with the size distribution fillers was set up. OLYM.

Tensile properties and die swell behaviours of highly filled polypropylene nanocomposites

“…For example, rheological percolation was observed when NFs concentration exceeded a critical value. As a result, the viscoelastic HFPNCs melts showed solid-like behaviour owing to the effect of filler–filler and filler–chains networks [2, 10-12].…”

Effect of inorganic particles gradation on the properties of high‐filled unsaturated polyester resin/CaCO3 composites

“…The mechanical properties of the composites are closely related to their macroscopic defect morphology, the particle size distribution of the filler, and the contact state of the microscopic interfaces between the fillers 30–33 . The results show that the thermoplastics filled with CaCO 3 with different particle size distributions have lower melting crystallization temperature and lower melting viscosity than the composites filled with a single particle size, which improves the machining and mechanical properties of the composites significantly 22,34–36 . In a study of mica as filler‐reinforced polypropylene, Busigin et al 37 noted that the modulus of the composite was related to the aspect ratio of the mica, and the strength was influenced the most by the size or scale diameter of the mica.…”

“…[30][31][32][33] The results show that the thermoplastics filled with CaCO 3 with different particle size distributions have lower melting crystallization temperature and lower melting viscosity than the composites filled with a single particle size, which improves the machining and mechanical properties of the composites significantly. 22,[34][35][36] In a study of mica as filler-reinforced polypropylene, Busigin et al 37 noted that the modulus of the composite was related to the aspect ratio of the mica, and the strength was influenced the most by the size or scale diameter of the mica. However, in the field of high-filled thermosetting resin composites, there is a lack of corresponding research on CaCO 3 gradation, leading to the question of how CaCO 3 gradation affects the material properties is long puzzled.…”

Effect of filler content, size, aspect ratio and morphology on thermal, morphological and permeability properties of porous talc filled—Polypropylene obtained throughMEAUSprocess

“…The use of mineral fillers can provide to the membrane an increase in rigidness, an enhancement of the hydrophilic surface characteristic and also can affect to the final porous morphology of the membranes, as most of the fillers have some nucleating ability in the crystallization processes of polyolefins. [7][8][9][10][11][12] Caihong et al [13] used magnesium sulfate whiskers as filler and showed that with increasing whiskers content the porosity of the stretched microporous membranes decreased, whereas the Gurley value showed an increase in values, they also showed that the introduction of MgSO 4 up to 10 wt.% did not induce pronounced changes in the pore structure and air permeability properties of the stretched microporous membranes.…”