Non-isothermal rheological response in melt spinning and idealized elongational flow

1976 ◽  
Vol 16 (11) ◽  
pp. 735-741 ◽  
Author(s):  
M. Matsui ◽  
D. C. Bogue
Keyword(s):  
Melt Spinning ◽  
Elongational Flow ◽  
Rheological Response

Theory and Simulation of Fiber Texture Formation and Rheology of Carbonaceous Mesophase Fibers

2001 ◽  
Vol 709 ◽  
Author(s):  
A. D. Rey
Keyword(s):  
Liquid Crystals ◽  
High Performance ◽  
Melt Spinning ◽  
Elongational Flow ◽  
Fiber Texture ◽  
Texture Formation ◽  
Cross Sectional ◽  
Wide Range ◽  
Spinning Process ◽  
Sectional Shape

ABSTRACTCarbonaceous mesophases are discotic nematic liquid crystals that are spun into high performance carbon fibers using the melt spinning process. The spinning process produces a wide range of different fiber textures and cross-sectional shapes. Circular planar polar (PP), circular planar radial (PR) textures, ribbon planar radial (RPR), and ribbon planar line (RPL) textures are ubiquitous ones. This paper presents, solves, and validates a model of mesophase fiber texture formation based on the classical Landau-de Gennes theory of liquid crystals, adapted here to carbonaceous mesophases. The effects of fiber cross-sectional shape and elongational flow on texture formation are characterized. Emphasis is on qualitative model validation using existing experimental data [1, 2]. The results provide additional knowledge on how to optimize and control mesophase fiber textures.

Non‐Isothermal Rheological Response During Elongational Flow

1977 ◽  
Vol 21 (4) ◽  
pp. 453-468 ◽  
Author(s):  
Takayoshi Matsumoto ◽  
Donald C. Bogue
Keyword(s):  
Elongational Flow ◽  
Rheological Response

scholarly journals Structure–Property Relationships in Bionanocomposites for Pipe Extrusion Applications

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 782
Author(s):  
Luigi Botta ◽  
Francesco Paolo La Mantia ◽  
Maria Chiara Mistretta ◽  
Antonino Oliveri ◽  
Rossella Arrigo ◽  
...  
Keyword(s):  
Low Frequency ◽  
Elongational Flow ◽  
Structure Property ◽  
Remarkable Effect ◽  
Suitable Material ◽  
Rheological Response ◽  
Structure Property Relationships ◽  
Potential Alternative ◽  
Pipe Extrusion ◽  
Material Ductility

In this work, bionanocomposites based on different biodegradable polymers and two types of nanofillers, namely a nanosized calcium carbonate and an organomodified nanoclay, were produced through melt extrusion, with the aim to evaluate the possible applications of these materials as a potential alternative to traditional fossil fuel-derived polyolefins, for the production of irrigation pipes. The rheological behavior of the formulated systems was thoroughly evaluated by exploiting different flow regimes, and the obtained results indicated a remarkable effect of the introduced nanofillers on the low-frequency rheological response, especially in nanoclay-based bionanocomposites. Conversely, the shear viscosity at a high shear rate was almost unaffected by the presence of both types of nanofillers, as well as the rheological response under nonisothermal elongational flow. In addition, the analysis of the mechanical properties of the formulated materials indicated that the embedded nanofillers increased the elastic modulus when compared to the unfilled counterparts, notwithstanding a slight decrease of the material ductility. Finally, the processing behavior of unfilled biopolymers and bionanocomposites was evaluated, allowing for selecting the most suitable material and thus fulfilling the processability requirements for pipe extrusion applications.

Elongational flow of polyethylenes in isothermal melt spinning

1993 ◽  
Vol 37 (6) ◽  
pp. 1041-1056 ◽  
Author(s):  
Pascale Revenu ◽  
Jacques Guillet ◽  
Christian Carrot
Keyword(s):  
Melt Spinning ◽  
Elongational Flow

scholarly journals Elongational Flow in Melt Spinning of Glass

1980 ◽  
Vol 8 (2) ◽  
pp. 60-66 ◽  
Author(s):  
Osamu ISHIZUKA ◽  
Kiyohito KOYAMA ◽  
Katsuhiro AOKI ◽  
Hiroaki SHOONO
Keyword(s):  
Melt Spinning ◽  
Elongational Flow

EM of rapidly solidified permanent magnets

1992 ◽  
Vol 50 (1) ◽  
pp. 198-199
Author(s):  
Raja K. Mishra
Keyword(s):  
Melt Spinning ◽  
Permanent Magnets ◽  
Dark Field Image ◽  
Dark Field ◽  
Maximum Energy ◽  
Quench Rate ◽  
Maximum Energy Product ◽  
Energy Product ◽  
Annular Dark Field ◽  
Rapidly Solidified

The discovery of a new class of permanent magnets based on Nd2Fe14B phase in the last decade has led to intense research and development efforts aimed at commercial exploitation of the new alloy. The material can be prepared either by rapid solidification or by powder metallurgy techniques and the resulting microstructures are very different. This paper details the microstructure of Nd-Fe-B magnets produced by melt-spinning.In melt spinning, quench rate can be varied easily by changing the rate of rotation of the quench wheel. There is an optimum quench rate when the material shows maximum magnetic hardening. For faster or slower quench rates, both coercivity and maximum energy product of the material fall off. These results can be directly related to the changes in the microstructure of the melt-spun ribbon as a function of quench rate. Figure 1 shows the microstructure of (a) an overquenched and (b) an optimally quenched ribbon. In Fig. 1(a), the material is nearly amorphous, with small nuclei of Nd2Fe14B grains visible and in Fig. 1(b) the microstructure consists of equiaxed Nd2Fe14B grains surrounded by a thin noncrystalline Nd-rich phase. Fig. 1(c) shows an annular dark field image of the intergranular phase. Nd enrichment in this phase is shown in the EDX spectra in Fig. 2.

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