- 學位論文
ePTFE電漿改質膜之剝離強度研究
A study on peel strength of plasma modified ePTFE membrane
摘要
本研究主要是以Ar、O2氣體無線電波電漿對聚四氟乙烯（ePTFE）樹脂進行表面處理，之後再誘導接枝不同親水性單體，如丙烯醯胺 (acrylamide, AAm)、甲基丙稀酸環氧丙脂（Glycidyl Methacrylate, GMA）、甲基丙烯酸羥乙酯(2-Hydroxyethyl Methacrylate, HEMA)。以探討不同氣體電漿改質ePTFE表面，親水性的變化及接枝不同單體後的界面黏著性質。並以ESCA、ATR-FTIR等表面分析儀器鑑定改質後ePTFE之結構，以SEM觀察PTFE表面型態的變化，及water contact angle量測探討親水性的變化。此外亦比較不同氣體電漿改質ePTFE膜，後接枝不同親水性單體黏著性質的差異，及與金屬銅箔間之黏著性。 研究中發現O2電漿在電漿前處理過程當中，對膜表面蝕刻效應顯著，同時在電漿狀態下，被蝕刻的-CFx‧基團會再以物理吸附的方式沈積回鐵氟龍表面，剝離力由3.65 N/cm下降至2.15 N/cm（未改質鐵氟龍表面剝離強度為2.47N/cm）。隨電漿功率的提升，此現象愈加明顯，剝離力急遽下降至1.05 N/cm（150W）。經氧電漿50W-60s前處理，後接枝AAm（接枝聚合反應溫度80℃，接枝聚合時間3小時，接枝單體濃度20 wt%）之鐵氟龍膜（[N]/[C]比值為0.208），剝離強度可提升至6.22±0.55 N/cm。 以Ar電漿前處理50W-120s，後接枝AAm（接枝聚合反應溫度80℃，接枝聚合時間3小時，接枝單體濃度10 wt%）之鐵氟龍膜([N]/[C]比值為0.214)，剝離強度可提升至5.61±0.20N/㎝。當AAm單體濃度超過10 wt%，在鐵氟龍表面會有一層AAm的接枝層，造成鐵氟龍膜表面與3M-600膠帶間無法緊密貼附，剝離力降至3.50±1.34 N/cm。
並列摘要
In this investigation, we attempt to improve the peel strength of ePTFE membrane by plasma treatment followed by grafting with hydrophilic monomers, such as Acrylamide (AAm)、Glycidyl methacrylate (GMA) and 2-Hydroxyethyl methacrylate (HEMA). The adhesion properties of the PTFE membrane were significantly improved by using plasma graft polymerization of AAm、GMA、and HEMA onto the surface of ePTFE membrane. The surface properties of the modified membrane were characterized by X-ray photoelectron spectroscopy (XPS), attenuated total refraction–Fourier transform infrared (ATR-FTIR), contact angle meter (CA), scanning electron microscopy (SEM) and Instron. In this study, it was found that heavy degradation was happened by the oxygen plasma treatment. Small molecular weight segments such as –CFx were formed due to the etching phenomenon on the ePTFE surface. By increasing the power of plasma, this phenomenon was more significantly. These -CFx segments might be re-deposition on to the ePTFE surface by physical adsorption and lead to the decrease of peel strength from 3.65 N/cm to 1.05 N/cm (peel strength between original ePTFE and adhesive is 2.47 N/cm). Optimum peel strength was obtained using an oxygen plasma treatment followed by grafting with 20 wt% AAm at 80 oC for 3 hr, giving a [N]/[C] ratio: 0.208 and improvement of peel strength to 6.22 ± 0.55 N/cm. In addition, the adhesion properties of the ePTFE membrane were significantly improved by oxygen plasma pretreated and followed by post grafting with AAm onto the surface of ePTFE membrane from 2.47 to 6.22 N/cm. On the other hand, the adhesion strength is lower by the argon plasma pretreated ePTFE membrane followed by post grafting with AAm than oxygen plasma pretreated one under the same condition. It suggests that due to the surface pore of ePTFE membrane were filled up with the homopolymer, the mechanical inter locking force between the ePTFE and adhesion was decreased, resulting in the drop of peel strength.