Adapting a Capillary Rheometer for Research on Polymer Melt Interfaces

Compared with in the conventional scales, the rheological properties of polymer melts have changed in the micro-scales. Based on the principle of capillary flow and modified with the method of Bagley or zero die micro-die, the rheological characteristics of polypropylene (PP) were investigated using the HAAKE capillary rheometer under the micro-die and conventional die. The results show that: the viscosity of polymer melt modified with the method of bagley or zero die micro-die in the different L/D ratio of micro-die is the same and the shear viscosity of PP decreases with the increase of shear rate; Compared with the viscosity in the conventional scales, the measured viscosity of PP in the micro-scales was reduced by 46% in 0.25mm diameter die, 44% in the 0.20mm diameter die and 88% in the 0.15mm diameter die at the same shear rate; a layer of fixed polymer melt was found in the inwall of the micro-die through the calculation of wall slip rate.

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Polymer Morphology Revealed by Staining Techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098204 ◽

1981 ◽

Vol 39 ◽

pp. 340-341

Author(s):

A. C. Reimschuessel ◽

V. Kramer

Keyword(s):

Polymer Melt ◽

Nylon 6 ◽

Morphological Features ◽

Negative Staining ◽

Polymer Morphology ◽

Crystallizable Polymer ◽

Staining Techniques ◽

Long Chain

Staining techniques can be used for either the identification of different polymers or for the differentiation of specific morphological domains within a given polymer. To reveal morphological features in nylon 6, we choose a technique based upon diffusion of the staining agent into accessible regions of the polymer.When a crystallizable polymer - such as nylon 6 - is cooled from the melt, lamellae form by chainfolding of the crystallizing long chain macromolecules. The regions between adjacent lamellae represent the less ordered amorphous domains into which stain can diffuse. In this process the lamellae will be “outlined” by the dense stain, giving rise to contrast comparable to that obtained by “negative” staining techniques.If the cooling of the polymer melt proceeds relatively slowly - as in molding operations - the lamellae are usually arranged in a radial manner. This morphology is referred to as spherulitic.

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The change in the efficiency of polyethylene inhibition during the diffusion saturation of the polymer melt with an antioxidant

Polymer materials and technologies ◽

10.32864/polymmattech-2017-3-3-41-48 ◽

2017 ◽

Vol 3 (2) ◽

pp. 41-48

Author(s):

D. G. Lin ◽

E. V. Vorobyova

Keyword(s):

Polymer Melt ◽

Diffusion Saturation

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Polymer melt rheology

10.1533/9780857092984 ◽

1994 ◽

Cited By ~ 35

Author(s):

F. N. Cogswell

Keyword(s):

Polymer Melt ◽

Melt Rheology

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A Study on Polymer Particle Flow in a Disk Zone of a Screw-Disk Extruder

Chemical and Process Engineering ◽

10.2478/cpe-2014-0009 ◽

2014 ◽

Vol 35 (1) ◽

pp. 121-135 ◽

Cited By ~ 3

Author(s):

Tomasz Rydzkowski ◽

Iwona Michalska-Pożoga

Keyword(s):

Mechanical Properties ◽

Computer Simulations ◽

Particle Motion ◽

Polymer Melt ◽

Experimental Tests ◽

Polymer Particle ◽

Particle Flow ◽

Material Particle ◽

Motion Trajectories ◽

Stretching Effect

Abstract The paper presents the summary of research on polymer melt particle motion trajectories in a disc zone of a screw-disk extruder. We analysed two models of its structure, different in levels of taken simplifications. The analysis includes computer simulations of material particle flow and results of experimental tests to determine the properties of the resultant extrudate. Analysis of the results shows that the motion of melt in the disk zone of a screw-disk extruder is a superposition of pressure and dragged streams. The observed trajectories of polymer particles and relations of mechanical properties and elongation of the molecular chain proved the presence of a stretching effect on polymer molecular chains.

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