| Summary: | 碩士 === 中原大學 === 化學系 === 88 === Abstract
Expanded PTFE and PTFE coexist the same physical properties, e.g. low frictional coefficient, high stability against heat, high resistance to chemical reagents, and high electric resistance. However, the hydrophobicity limits its several application. To improve its surface property, many methods have been employed, e.g. treatment with high-energy irradiation, ozone, corona discharge and plasma. Among them, the “Plasma Surface Modification” has the advantages of safe, effective, low pollution and so on. There are several differences between expanded PTFE and PTFE. For example, ePTFE was constituted with nodes and fibers, and the average pore size of the ePTFE sheet is 1 µm.
The surface modifications of ePTFE sheet have been accomplished with C2H4, CO2 and Ar microwave plasma treatment to improve its hydrophilicity. And the modified ePTFE were then characterized by a combination of attenuated total reflection Fourieer transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), electron spectroscopy for chemical analysis (ESCA), static contact angle measurement and dynamic contact angle measurement with Wilhelmy Plate Method.
The results of ESCA showed that all the C2H4, CO2 and Ar microwave plasma were able to activate the surface of the ePTFE sheet, and the sheet was modified after graft polymerization with acrylic acid (AAc). Under the similar plasma pretreatment condition, it was found that the C2H4 plasma treatment gave a better value of [O]/[C] and [F]/[C] ratio. SEM observations revealed that the morphology of the ePTFE sheet changed with grafting time both on the surface and the cross-section nearby the surface. The data obtained from the plasma modified ePTFE show that the hydrophilicity of ePTFE sheet were improved by static contact angle measurement and Wilhelmy Plate Method.
|
|---|
