利用超臨界二氧化碳進行聚碸薄膜表面接枝之研究

Surface Grafting of Polysulfone Membrane Using Supercritical Carbon Dioxide

陳宗勤(Tsung-Chin Chen)

指導教授 ： 陳延平

國立臺灣大學/工學院/化學工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.02266

摘要

聚碸高分子薄膜（polysulfone membrane）是一種被廣泛使用的血液透析薄膜，然而PSf薄膜卻具有疏水性的表面，導致其生物相容性不佳，限制了PSf在血液透析中的應用。本實驗利用超臨界二氧化碳（SCCO2）取代傳統有機溶劑，以2,2’-azobisisobutyronitrile（AIBN）做為起始劑，利用自由基接枝聚合法將丙烯酸（AAc）及甲基丙烯酸羥乙酯（HEMA）等親水性單體接枝在PSf薄膜上，使疏水性表面改質成為親水性。
　　實驗中我們藉由調整反應溫度、操作壓力、反應時間及反應物濃度等操作參數來控制接枝的程度。接枝HEMA單體時，當反應溫度為80℃、壓力為17.5 MPa、AIBN及HEMA濃度分別為0.04 M及0.12 M，在反應時間5小時的操作條件下，可以得到最大的接枝重量百分比 36.0 wt%。而PSf薄膜的親水性可隨著接枝程度的增加而增加，表面接觸角可從原來的88.6o ± 1.1降至43.0o ± 2.4（n=10）。
　　然而在接枝AAc的系統中，當反應溫度為85℃、壓力為17.5 MPa、AIBN及AAc濃度分別為0.04 M及0.12 M，反應時間則僅需3小時，可以得到最大的接枝重量百分比 20.4 wt%。而其表面接觸角則可以從88.6o ± 1.1降至43.2o± 3.0（n=10）。
　　薄膜改質後可由Fourier transform infrared spectroscopy （FTIR）分析薄膜表面的化學性質，scanning electron microscopy（SEM）觀察表面型態上的改變，differential scanning calorimetry （DSC）分析熱性質的變化，以及X-ray Induced Photoelectron Spectroscop（XPS）分析表面蛋白質吸附的情形。由以上諸多分析實驗結果，可證明我們可以利用超臨界二氧化碳做為溶劑，成功的將HEMA及AAc接枝於PSf薄膜表面上，並能有效的將疏水性的薄膜表面改質成為親水性。

關鍵字

聚碸超臨界二氧化碳 ； 自由基接枝聚合 ； 丙烯酸 ； 甲基丙烯酸羥乙酯

並列摘要

Polysulfone (PSf) is a widely used material in membrane for hemodialysis. However, the hydrophobic nature of PSf limit its application in hemodialysis. Graft acrylic acid (AAc) and 2-Hydroxyethyl methacrylate (HEMA) monomer onto PSf membrane by free-radical polymerization using supercritical carbon dioxide (SCCO2) as a solvent and swelling agent. The PSf membrane was first impregnated with the monomer and initiator AIBN with SCCO2, and the monomer molecules were grafted onto the PSf membrane at a higher temperature. By this method, the grafting level can be controlled by temperature, pressure, reaction time, and concentration of reaction agents. When temperature is 80℃, pressure is 17.5 MPa, the concentration of HEMA and AIBN are 0.12M and 0.04M. At reaction time 5h, the grafting percentage of PSf-g-HEMA is 36.0 wt%. Further, at the optimal condition of grafting AAc, the grafting percentage is 20.4 wt%.
The modified surfaces were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), contact angle and X-ray induced photoelectron spectroscop (XPS). The hydrophilicity of the membranes is increased after grafting. The contact angle of modified PSf membranes are reduced from 88.6o ± 1.1 to 43.0o ± 2.4 (n=10).

並列關鍵字

polysulfone ； acrylic acid ； HEMA ； grafting ； SCCO2

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