4 edition of Solutocapillary convection effects on polymeric membrane morphology found in the catalog.
Solutocapillary convection effects on polymeric membrane morphology
by National Aeronautics and Space Administration, National Technical Information Service, distributor in [Washington, D.C, Springfield, Va
Written in English
|Statement||William B. Krantz, Paul W. Todd.|
|Series||[NASA contractor report] -- NASA CR-202378.|
|Contributions||Todd, Paul W., United States. National Aeronautics and Space Administration.|
|The Physical Object|
1. Introduction. Mixed matrix membranes (MMMs), which consist of a continuous polymeric phase and a dispersed inorganic particle phase (porous or non-porous), have been receiving increasing attention in the field of gas separations [1,2].Many studies have demonstrated higher gas permeability and/or selectivity for the MMMs when compared to the conventional homogeneous polymeric membranes Cited by: The surface morphology and phase separation structure of polyurethane/butyl hydroxypropyl cellulose ester (PU/BPC) composite membranes with different BPC contents and underwent different post-treatments were investigated by using polarized optical microscopy (POM), scanning electron microscopy (SEM) and small angle X-ray scattering (SAXS).Cited by:
The effect of UV-irradiation time and addition of AA on the performance and morphology of nanofiltration membranes were investigated. The obtained membranes illustrate the ability for rejection of Na 2 SO 4 and significant properties for separation of divalent ions from monovalent ions [ 3 ].Cited by: 2. Macrovoid growth during polymer membrane casting Macrovoid growth during polymer membrane casting Khare, Vivek P.; Greenberg, Alan R.; Zartman, Jeremiah; Krantz, William B.; Todd, Paul The Solutocapillary Convection (SC) hypothesis contends that macrovoid (MV) growth in dry-cast membranes is governed by a solutal-Marangoni convection-induced force .
and stable performance. Polymer blending can be done by blending the main polymer with polymers that can form a hydrogen bond. The formation of a hydrogen bond leads to compatibilization of the blend polymer. Blend membranes must have IEC of to mmol/g and show low ionic resistances for application in electromembranes .Author: Monaheng L Masheane, Arne Verliefde, Sabelo Mhlanga. Fabrication of hollow fiber membranes by phase inversion 1. &CHAPTER 31 Fabrication of Hollow-Fiber Membranes by Phase Inversion TAI-SHUNG NEAL CHUNG Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore INTRODUCTION Since Mahon proposed using hollow-ﬁber membranes as separation .
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Get this from a library. Solutocapillary convection effects on polymeric membrane morphology: final report. [William B Krantz; Paul W Todd; United States. acetatemembrane showing a dense top layer or "skin" and a porous sublayer with larger macrovoid pores.
The presence of macrovoid pores in large numbers can result in compaction and/or collapse of polymeric membranes and hence in a reduction of flux in. Solutocapillary convection is flow-caused by a concentration induced surface-tension gradient.
Macrovoid growth in the former hypothesis is gravity independent, while in the latter it is opposed by gravity. To distinguish between these two hypotheses, experiments were designed to cast membranes.
including the solutal Marangoni convection force (solutocapillary convection), viscous drag force, and the buoyancy force. Despite these prior studies, many aspects of membrane morphology development including the initiation and growth of macrovoid pores are not well understood.
Consequently, the overall. Under certain conditions the polymer-lean phase gives rise to very large and usually undesirable, tear-drop-shaped pores (size approx. 10 - 50 microns) termed macrovoids (MVs).
Although in many cases the presence of MV pores has deleterious effects on membrane performance, there are a number of innovative applications where the presence of such pores is highly desirable. Buoyancy should have no effect on MV growth as proposed in the purely diffusive growth hypothesis but should influence MV growth via the solutocapillary convection hypothesis since the latter.
The Solutocapillary Convection (SC) hypothesis contends that macrovoid (MV) growth in dry-cast membranes is governed by a solutal-Marangoni convection-induced force caused by the rapid evaporation of volatile solvent from the liquid/gas interface, a viscous drag force Cited by: CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): The Solutocapillary Convection (SC) hypothesis contends that macrovoid (MV) growth in dry-cast membranes is governed by a solutal-Marangoni convection-induced force caused by the rapid evaporation of volatile solvent from the liquid/gas interface, a viscous drag force, and a gravity-induced buoyancy force.
Effect of Non-Solvents Used in the Coagulation Bath on Morphology of PVDF Membranes (DMF) from Vetec. The non-solvents used were distilled water and ethanol from Simoquímica.
The support used was woven macroporous % polyester with a thickness of µm purchased from Notredame Trade and Imports. Membrane preparation. Effect of porosity on the free convection flow of non-Newtonian fluids along vertical plate embedded in a porous media was presented by Beithou et al.
Yih () investigated the effect uniform lateral mass flux on natural convection of non-Newtonian fluids over a cone in porous media. Free convection. 1 Article 2 PVDF membrane morphology - influence of polymer 3 molecular weight and preparation temperature.
4 Monika Haponska 1, Anna Trojanowska 2,*, Adrianna Nogalska3, Renata Jastrzab 4, Tania Gumi 5 5 and Bartosz Tylkowski 6,* 6 1 Departament d’ enginyeria química, Universitat Rovi ra i Virgili, Av. dels Països Catal 7 Tarragona, Spain; A. Mickiewicz University, Faculty of Cited by: Introduction Polymeric membranes can be formed via evaporative (dry) casting whereby a single-phase polymer/ solvent/non-solvent (P/S/NS) solution is caused to Author: A.
Greenberg, V. Khare, J. Zartman, W. Krantz, P. Todd. Konagurthu cites these effects as evidence that solutocapillary convection is indeed important to MV formation in dry-cast membranes. This paper describes the results of recent modeling efforts and the data obtained from casting experiments conducted in 0- and 1- Cited by: We have studied, for the first time, the effects of spinneret dimension and its coupling effect with air gap distance on macrovoid evolution.
Spinnerets with different annulus gaps, i.e., from to mm, were fabricated. Hollow fiber membranes spun from thinner spinneret annulus gaps show only inward-pointed long, teardrop, and elliptical shape macrovoids, while those spun from thicker Cited by: Long-Time Observation of Near-Critical Spinodal Decomposition of Colloid-Polymer Mixtures in Microgravity.
Peter Lu, David Weitz, Gregory Chamitoff, Leroy Chiao, E. Fincke, Michael Foale, Sandra Magnus, William McArthur, Daniel Tani, Peggy Whitson, Jeffrey Williams, Catherine Frey, Brion Au, William Meyer and Ronald Sicker.
Effect of non-solvents used in the coagulation bath on morphology of PVDF membranes. Mônica Beatriz Thürmer I, *; Patrícia Poletto II; Marcos Marcolin II; Jocelei Duarte II; Mara Zeni II. I Materials Engineering Department, Universidade Federal do Rio Grande do Sul - UFRGS, CEPPorto Alegre, RS, Brasil II Science and Technology Center, Universidade de Caxias do Sul - UCS, Caxias.
The onset and stability of solutal (buoyancy and Marangoni) convection induced by a localized source of surface-active substance placed under an interface were studied both experimentally and theoretically.
It was shown that the competition between the buoyancy and solutocapillary convection can lead to the onset of oscillatory convection.
The period of the observed oscillations Cited by: 3. Abstract. This chapter mainly describes the principles of membrane formation process for polymeric membranes.
With a brief introduction of relevant background information such as various membranes and membrane processes, a comprehensive list of polymer materials, which are suitable for making membranes, has been by: The polymer membranes of cellulose triacetate-o-NPPE with 1-alkylimidazole were characterised by scanning electron microscopy, non-contact atomic force microscopy and thermal analysis techniques.
The influence of membrane morphology on the Zn(II). Books by Language Additional Collections Journal of materials engineering. Journal of paediatric dentistry. Featured movies All video. TY - BOOK. T1 - Nanoporous Polymers for Membrane Applications. AU - Li, Li. PY - Y1 - N2 - Membrane technology has been realized as a useful tool in a variety of applications, such as health sector, food industry, sustainable water treatment and energy conversion and by: Effect of sintering temperature on the morphology and mechanical properties of PTFE membranes as a base substrate for proton exchange membrane Songklanakarin J.
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