Morphology development of PC/PE blends during compounding in a twin‐screw extruder

Abstract

The morphological development of a polycarbonate/ polyethylene (PC/PE) blend in a twin-screw extruder was studied using a scanning electron microscope (SEM). The effects of extrusion temperature, viscosity ratio (the ratio of the viscosity of the dispersed phase to that of the matrix), and the screw configuration on the morphology of the PC/PE blend during the extrusion were discussed in detail. It was found that the morphology of the dispersed particles and the interfacial adhesion between the dispersed phase and matrix were both influenced by the extrusion temperature. The dispersed phase had a spheroidal shape and a small size during the high temperature processing, and an irregular shape and a large size when it was processed at low temperature. The PC phase with a lower viscosity was easier to disperse and also to coalesce. Therefore, the deformation of the low-viscosity dispersed phase during the processing was more intense than that of the high-viscosity dispersed phase. By comparing the effects of the different screw configurations on the morphology development of the PC/PE blend, it was found that the melting and breaking up of the dispersed phase were mainly affected in the initial blending stages by the number of the kneading blocks. While a kneading block with a 90 degree staggering angle was used, the size of the dispersed particles decreased and the long fibers were shortened, the large particles were drawn by the additional kneading zone. Finally, all of these structures were completely changed to the short fibers. POLYM.

Synthesis of Reactive Comb Polymers and Their Applications as a Highly Efficient Compatibilizer in Immiscible Polymer Blends

“…The shear stress was constant in our experiment, while the interfacial tension was significantly reduced by the RL or RC compatibilizers, and so the morphology development indicated a variation of interfacial tension; the greater deformation implied a lower interfacial tension and furthermore a better emulsifying effect of the in-situ formed PLLA grafted RC polymers at the interface. [43][44][45][46][47][48] As shown in Figure S8, the higher magnification TEM micrographs showed that many white particles (30~40 nm in diameter) existed in the PVDF phase when the blends were compatibilized by RL and these particles might be correlated with the PLLA grafted RL polymers, which were drawn from the interface under shear condition. [49][50][51][52] It was noteworthy that such tiny particles were scarcely found in the PVDF phase of the blends compatibilized by RC.…”

In‐line turbidity monitoring of the second phase droplets deformation during extrusion

“…With the increase of the screw rotation and post‐extrusion speed, which increased the shear stress rate, reduced the second phase particles diameter. Yin et al analyzed the influence of the viscosity ratio, temperature condition, and screw configuration on the morphology development of PC/PE blends. In the case of extrusion temperature, its increase reduces the size of the particles.…”

Morphology prediction and the effect of core‐shell structure on the rheological behavior of PP/EPDM/HDPE ternary blends

“…Polymer blends have been widely applied as a versatile method in the industry because of their ability to improve the performance of materials for specific applications, at a relatively low cost when compared with the development of a new polymer [1–7]. Recently, in order to obtain better properties of polymer materials, great efforts have been taken to develop multicomponent polymer blends with advanced properties such as increase of modulus and strength, electrical conductivity, improved barrier properties, increase in solvent and heat resistance, and enhancement of good optical transparency [6, 8, 9].…”