- 學位論文
常壓電漿接枝類雙離子材料於高分子薄膜之研究
Modification of Polymeric Membranes with Pseudo-zwitterionic Materials by Atmospheric-pressure Plasma
摘要
本研究以常壓輝光介電質放電對聚偏二氟乙烯同時進行表面活化與接枝步驟，接枝甲基丙烯醯氧乙基三甲基氯化銨（TMA）與3-磺酸丙基甲基丙烯酸鉀鹽（SA）製備出仿生薄膜，其中單體TMA帶正電荷，SA帶負電荷。電漿處理後的膜材利用水接觸角、全反射式傅立葉轉換紅外線光譜儀、掃描式電子顯微鏡、X射線光電子能譜儀、界達電位量測儀等儀器分析表面化學與物理特性，再進行蛋白質吸附及細菌貼附測試，瞭解膜材抗生物沾黏之效果，同時於血液實驗中測量改質薄膜之血液相容性，並利用蛋白循環過濾測試探討膜材之水通量恢復效能。 常壓輝光介電質放電於固定功率為100 W，改質時間為60 s的電漿參數下製備之PVDF-g-(TMA/SA)改質膜材，經由ATR-FTIR與XPS分析所得之正電荷與負電荷比例瞭解表面電性，當表面呈電中性時最接近仿生薄膜，具有抗生物沾黏效能。生物分子沾黏實驗中，單體配比TMA:SA = 1:1於電漿接枝後表面最接近電中性，能有效抵抗相反電性的蛋白質吸附、血球以及細菌的貼附，並且於蛋白循環測試有90%以上的水通量恢復效能，具備可利用性的價值，可應用於生醫薄膜材料或過濾廢水處理的產業；單體配比TMA:SA = 2:1於電漿接枝後，蛋白循環過濾中也有良好的恢復力，但不具備抵抗血球沾黏的效能，因此僅能應用於廢水回收之過濾薄膜。 本研究所開發的常壓輝光介電質放電可以快速、乾淨、均勻的製備仿生膜材，達到抗生物分子沾黏的性質，其中表面電性為生物分子吸附的原因之一，可運用不同單體電性之混合配比下，製備出所需的表面電性，是一種新穎的技術。
並列摘要
Membrane technology is important in wastewater treatment and bioseparation applications. However, biofouling arising from protein adsorption and biofilm formation are of great concern because of significant reduction in utilization and increase in operational cost. The cell membrane can prevent the adsorption of proteins in the blood stream owing to the zwitterionic characteristics of the phospholipid molecules on cell membranes. Thus, it is of great interest to synthesize biomimetic membranes to reduce protein adsorption in bioseparation processes. In this study, a novel atmospheric dielectric barrier discharge (DBD) plasma was used to graft 2-[(methacryloyloxy) ethyl] trimethylammonium chloride (TMA) and 3-Sulforpopyl methacrylate potassium salt (SA) onto poly(vinylidene fluoride) (PVDF) membrane. The chemical structure, surface morphology of the surface-modified PVDF membranes were characterized by Fourier Transform Infrared-Attenuated Total Reflectance（FTIR-ATR）, Electron Spectroscopy for chemical analysis（ESCA）, Scanning Electron Microscopy（SEM）, Laser Scanning Confocal Microscope（CLSM）, Zeta Potential and Contact Angle. In addition, the anti-biofouling capability of prepared membranes was characterized by the protein adsorption of bovine serum albumin（BSA）and Lysozyme. It was tested with the human blood cell and attachment ability with Escherichia coli. Lastly, cyclic filtration test was done BSA solution. After modification of PVDF membrane, it was found that at monomer ratio, TMA : SA = 1:1（T1S1）, the grafting density was around at 0.36 mg/cm2. The functional groups of two monomers TMA and SA are of positively（N+(CH3)3） and negatively（SO3-）, respectively. The PVDF-g-T1S1 membrane performances of zwitterionic surface were characterized by XPS, ATR-FTIR and zeta potential. The zwitterionic surface of membranes not only can prevent protein adsorption, but also can resist the human blood cell and Escherichia coli bacterial attachment. Thus, preparation of pseudo-zwitterionic materials by atmospheric-pressure plasma is succeeful. Flux recovery of water（FRwi）was calculated using the data of the cyclic filtration, PVDF-g-T1S1 of FRwi is 92.6% in the second cycle. The PVDF-g-T1S1 membrane could effectively resist protein adsorption and exhibited an extremely low biofouling characteristic during the cyclic filtration. The results indicated the importance of charge balances on the membrane surface owing to protein fouling human blood cell and bacterial adhesion.