How to distinguish between hydrophobic and hydrophilic membranesIssuing time:2023-03-08 18:03 Hydrophobic andhydrophilic membranes can be distinguished based on their behavior towardswater molecules. A hydrophobic membrane repels water and is not wetted by it,while a hydrophilic membrane attracts water and is easily wetted by it. Here are somemethods to distinguish between hydrophobic and hydrophilic membranes: 1. Contact angle measurement:This is a commonly used method to measure the wettability of a surface. Adroplet of water is placed on the membrane, and the angle formed between thedroplet and the membrane surface is measured. A hydrophobic membrane will havea high contact angle, typically above 90 degrees, indicating that waterdroplets do not spread easily on its surface. In contrast, a hydrophilicmembrane will have a low contact angle, typically below 90 degrees, indicatingthat water droplets spread easily on its surface. 2. Membranefiltration test: Hydrophobic membranes are commonly used in filtrationapplications to separate non-polar compounds from water. In this test, ahydrophobic membrane is used to filter a mixture of water and oil. Thehydrophobic membrane will allow the oil to pass through while retaining thewater. In contrast, a hydrophilic membrane would allow both oil and water topass through. Membrane surfacecharge: Hydrophilic membranes typically have charged surface groups thatattract water molecules. This charge can be measured using zeta potentialmeasurements. In contrast, hydrophobic membranes have a neutral or hydrophobicsurface, which does not attract water molecules. 3. Waterpermeability: Hydrophilic membranes typically have a higher water permeabilitythan hydrophobic membranes. This can be measured using permeability tests,where the rate of water flow through the membrane is measured under controlledconditions. Overall, thewettability of a membrane is a critical parameter that determines itsperformance in various applications. Determining the hydrophobic or hydrophilicnature of a membrane is important in choosing the appropriate membrane for agiven application. 声明:此篇为华合盛科技原创文章,转载请标明出处链接:www.szhhstech.comhttps://szhhstech.com/sys-nd/32.html
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