Effects of kinetics coefficients on ternary phase separation during the wet spinning process

2012 ◽  
Vol 125 (5) ◽  
pp. 3630-3637 ◽  
Author(s):  
Yu Han ◽  
Jun Wang ◽  
Hongdong Zhang
Keyword(s):  
Phase Separation ◽  
Ternary Phase ◽  
Wet Spinning ◽  
Spinning Process

scholarly journals Compositions Based on PAN Solutions Containing Polydimethylsiloxane Additives: Morphology, Rheology, and Fiber Spinning

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 815
Author(s):  
Valery G. Kulichikhin ◽  
Ivan Y. Skvortsov ◽  
Lydia A. Varfolomeeva
Keyword(s):  
Phase Separation ◽  
Continuous Medium ◽  
Viscosity Ratio ◽  
Fiber Spinning ◽  
Wet Spinning ◽  
Diffusion Front ◽  
Molecular Weights ◽  
Effect Of Additives ◽  
Coalescence Rate ◽  
Spinning Process

The effect of additives of polydimethylsiloxanes (PDMS) with various molecular weights on the morphology and rheological behavior of polyacrylonitrile (PAN) solutions in dimethyl sulfoxide has been analyzed. It was shown that only partial compatibility of the PDMS with the lowest molecular weight member of the homologous series studied—hexamethyldisiloxane—with PAN solution takes place. All other PDMS samples form emulsions with PAN solutions. The coalescence rate of PDMS drops depends on the viscosity ratio of the disperse phase and the continuous medium, which determines both the duration of dispersion preparation and the conditions for processing emulsions into fibers and films. An anomalous change in viscosity for a series of emulsions with different concentrations of additives, associated with the slippage, was detected. The relaxation properties of emulsions “feel” macro-phase separation. Modeling of the wet spinning process has shown that the morphology of the deposited solution drop reflects the movement of the diffusion front, leading to the gathering droplets in the center of the deposited formulation drop or to their localization in a certain arrangement. It was shown that the emulsion jets upon stretching undergo phase separation.

Theoretical and experimental investigation of the wet-spinning process for mechanically strong carbon nanotube fibers

2021 ◽  
Vol 412 ◽  
pp. 128650
Author(s):  
Hyeon Dam Jeong ◽  
Seo Gyun Kim ◽  
Gyeong Min Choi ◽  
Minji Park ◽  
Bon-Cheol Ku ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Carbon Nanotube ◽  
Wet Spinning ◽  
Spinning Process ◽  
Carbon Nanotube Fibers

scholarly journals Effects of solvent sort on casting solution and morphology of poly(ether sulfones) filtration membrane

2020 ◽  
Author(s):  
Kai Fan ◽  
Chun Liu ◽  
Haijun Yang ◽  
Zhengchi Hou
Keyword(s):  
Phase Diagram ◽  
Phase Separation ◽  
Shear Viscosity ◽  
Ternary Phase ◽  
Ternary Phase Diagram ◽  
Viscosity Measurement ◽  
Micro Structure ◽  
Filtration Membranes ◽  
Filtration Membrane ◽  
Thermodynamics And Dynamics

Abstract Four kinds of solvent were chosen to prepare poly(ether sulfones) (PES) filtration membranes by the nonsolvent induced phase separation (NIPS) method. Ternary phase diagram and shear viscosity measurement were conducted to analyse the formation of prepared membrane from thermodynamic and kinetic perspectives. The micro-structure of the membranes with different solvents were analysed, and the result showed a high relevance to the thermodynamics and dynamics of the casting solutions, and promoted the proposal of a reasonable membrane formation mechanism.

Tough synthetic spider-silk fibers obtained by titanium dioxide incorporation and formaldehyde cross-linking in a simple wet-spinning process

Biochimie ◽  
2020 ◽  
Vol 175 ◽  
pp. 77-84
Author(s):  
Hongnian Zhu ◽  
Yuan Sun ◽  
Tuo Yi ◽  
Suyang Wang ◽  
Junpeng Mi ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Spider Silk ◽  
Wet Spinning ◽  
Cross Linking ◽  
Silk Fibers ◽  
Spinning Process

Effect of coagulation bath parameters on the morphology and absorption behavior of a skin–core filament based on biomedical polyurethane and native silk fibroin microparticles

2019 ◽  
Vol 90 (3-4) ◽  
pp. 460-468 ◽  
Author(s):  
Yan Zhuang ◽  
Han Wang ◽  
Linfeng Wang ◽  
Changjun Liu ◽  
Yuan Xu ◽  
...  
Keyword(s):  
Drug Release ◽  
Water Absorption ◽  
Silk Fibroin ◽  
Controlled Drug Release ◽  
Coagulation Bath ◽  
Wet Spinning ◽  
Electron Microscopy Analysis ◽  
Potential Applications ◽  
Spinning Process ◽  
Biomedical Polyurethane

This study investigates the effect of the constituents and temperature of a coagulation bath on the morphology and water absorption behavior of a skin–core filament, which has potential application in the field of controlled drug release, based on biomedical polyurethane (BPU) and native silk fibroin microparticles (NSFPs). BPU solution and BPU/NSFP blend solution were extruded from the cortex and core channel of a coaxial double injector into a coagulation bath with different constituents and at different temperatures to form filaments. Scanning electron microscopy analysis of the skin–core filament prepared by wet-spinning revealed that the addition of ethanol decreased the exchange speed between the solvent and non-solvent and led to the formation of micropores on the surface. Meanwhile, the interface between the cortex and core became pronounced and the water absorption capability of the filament decreased with increasing ethanol concentration in the coagulation bath. The high temperature of the coagulation bath also improved the exchange speed between the solvent and non-solvent; however, its effect on the morphology of the filament was weak. Thus, a skin–core filament with different morphologies and water absorption behaviors was fabricated by controlling the constituents and temperature of the coagulation bath during the wet-spinning process. This skin–core filament has potential applications in controlled drug release.

Solid solid phase change (SSPC) chitosan-g-mPEG fiber with improved mechanical performance via in-situ wet spinning process

2020 ◽  
Vol 240 ◽  
pp. 116313 ◽  
Author(s):  
Da Bao ◽  
Lisha Liu ◽  
Ting Sun ◽  
Ying Han ◽  
Fanliang Meng ◽  
...  
Keyword(s):  
Phase Change ◽  
Mechanical Performance ◽  
Solid Phase ◽  
Wet Spinning ◽  
Spinning Process

Preparation of carrageenan fibers with extraction of Chondrus via wet spinning process

2018 ◽  
Vol 194 ◽  
pp. 217-224 ◽  
Author(s):  
Min Dong ◽  
Zhixin Xue ◽  
Jingjing Liu ◽  
Miao Yan ◽  
Yanzhi Xia ◽  
...  
Keyword(s):  
Wet Spinning ◽  
Spinning Process

On the wet spinning process of viscose fibres

1988 ◽  
pp. 388-391 ◽  
Author(s):  
K. Fischer ◽  
H. Sendner ◽  
R. Büchner ◽  
A. Schlesinger
Keyword(s):  
Wet Spinning ◽  
Spinning Process

Exploring the Thermodynamic Aspects of Structure Formation During Wet-Spinning of Polyacrylonitrile Fibres

2011 ◽  
Vol 1 (2) ◽  
pp. 36-52
Author(s):  
Shahram Arbab ◽  
A. Zeinolebadi ◽  
Parviz Noorpanah
Keyword(s):  
Phase Separation ◽  
High Strength ◽  
Solution Viscosity ◽  
Wet Spinning ◽  
Precipitation Process ◽  
Carbon Fibres ◽  
Electron Scanning Microscopy ◽  
Lower Porosity ◽  
On Line ◽  
Micrometer Size

Wet-spun polyacrylonitrile fibres are the main precursor for high strength carbon fibres. The properties of carbon fibres strongly depend on the structure of the precursor fibre. Polyacrylonitrile fibres were spun from solutions with varying solvent/nonsolvent content and different draw ratios. Wet-spinning is an immersion precipitation process, thus thermodynamic affinity of spinning dope to the coagulation medium was considered as the driving force of phase-separation, while viscosity of the solution accounted for the resistive force against phase separation and growth of the nucleated voids. Thermodynamic affinity was estimated by modifying Ruaan’s theory and viscosity of the solution was assessed on-line by measuring flow rate and back pressure at the spinneret. Hence, the parameter X (thermodynamic affinity/viscosity) was introduced to predict the porous morphology of the fibres. Generally, an increase in X led to fibres with higher porosity. A combination of electron scanning microscopy (SEM), porosimetry and thermoporometry was applied to fully characterize microstructure of fibres. Based on image analysis of SEM micrographs and data obtained from thermoporometry and porosimetry fractions of dense polymer ligament, micrometer size voids (macrovoids) and nanometer size voids (nanovoids) were estimated. Increasing polymer content or nonsolvent content in the spinning dope caused an increase in the solution viscosity and resulted in fibres with lower porosity. Imposing drawing on the as-spun fibres further decreased the porosity. Drawing also shifted the size distribution of nanovoids toward smaller values.

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