Analysis of the Morphological Development of PBT/ABS Blends during the Twin Screw Extrusion and Injection Molding Processes

2003 ◽  
Vol 18 (4) ◽  
pp. 376-381 ◽  
Author(s):  
E. N. Ito ◽  
L. A. Pessan ◽  
J. A. Covas ◽  
E. Hage
2014 ◽  
Vol 893 ◽  
pp. 132-135 ◽  
Author(s):  
Branislav Duleba ◽  
František Greškovič ◽  
Emil Spišák ◽  
Ľudmila Dulebová

In this paper, study of preparation and testing of polymer nanocomposites (PNC) based on polypropylene matrix and montmorillonite nanofillers is described. Samples were prepared by twin-screw extrusion and injection molding to final shape. Changes of basic properties of these PNC ́s were tested and described in main part of this article.


2014 ◽  
Vol 53 (4) ◽  
pp. 379-386 ◽  
Author(s):  
Michael A. Gunning ◽  
Luke M. Geever ◽  
John A. Killion ◽  
John G. Lyons ◽  
Clement L. Higginbotham

2013 ◽  
Vol 685 ◽  
pp. 19-23 ◽  
Author(s):  
Ali Sinan Dike ◽  
Harun Mindivan

The present work aims to compare the mechanical properties of Polypropylene (PP) based composites reinforced with B4C. Maleic Anhydride Modified Polypropylene (MAPP) was added to improve the B4C-matrix interphase. Processing has been carried out by twin-screw extrusion and injection molding. By adding the B4C particles to the PP and PP+MAPP matrix, the yield strength, shore D hardness, microhardness and relative scratch resistance increased gradually, but PP+MAPP/B4C composites showed better overall mechanical properties than the PP/B4C composites. However, elongation at break values occurred for all composites dropped with the B4C content, and PP+MAPP/B4C composites exhibited lower elongations at break than PP/B4C composites.


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2128
Author(s):  
Paulo F. Teixeira ◽  
José A. Covas ◽  
Loïc Hilliou

The dispersion mechanisms in a clay-based polymer nanocomposite (CPNC) during twin-screw extrusion are studied by in-situ rheo-optical techniques, which relate the CPNC morphology with its viscosity. This methodology avoids the problems associated with post extrusion structural rearrangement. The polydimethylsiloxane (PDMS) matrix, which can be processed at ambient and low temperatures, is used to bypass any issues associated with thermal degradation. Local heating in the first part of the extruder allows testing of the usefulness of low matrix viscosity to enhance polymer intercalation before applying larger stresses for clay dispersion. The comparison of clay particle sizes measured in line with models for the kinetics of particle dispersion indicates that larger screw speeds promote the break-up of clay particles, whereas smaller screw speeds favor the erosion of the clay tactoids. Thus, different levels of clay dispersion are generated, which do not simply relate to a progressively better PDMS intercalation and higher clay exfoliation as screw speed is increased. Reducing the PDMS viscosity in the first mixing zone of the screw facilitates dispersion at lower screw speeds, but a complex interplay between stresses and residence times at larger screw speeds is observed. More importantly, the results underline that the use of larger stresses is inefficient per se in dispersing clay if sufficient time is not given for PDMS to intercalate the clay galleries and thus facilitate tactoid disruption or erosion.


Sign in / Sign up

Export Citation Format

Share Document