臺灣博碩士論文加值系統

　　　　靜電紡絲為製備纖維方法之一,在高分子領域方面,為經常使用的技術在文獻報導指出聚胺酯(Polyurethanes，PU)已經被廣泛使用靜電紡絲的技術，其應用範圍包括各種材料，例如：塑膠材料、生醫材料等。因此PU的應用在化學和商業的發展成為一項重要課題。然而奈米碳管具有良好的熱傳導性和機械性質之奈米材料，常做為添加劑加入至高分子中增強其性質。本實驗將先以聚氧四亞基二醇(PTMO，M.W=2900) 和4,4’-二苯甲烷二異氰酸鹽(MDI)以莫耳比1:3之比例先形成預聚物，再以1.4-丁二醇(BD)之混合溶液鏈延長合成PU，最後再與酸化或氯醯化之多壁奈米碳管(MWCNTs)進行混合，並以靜電紡絲方法將其噴絲製成聚胺酯/多壁奈米碳管複合材料(PU/MWCNTs)。

　　藉由FTIR、NMR鑑定材料其結構，證明成功將奈米碳管接枝於改質PU中。電子顯微鏡(SEM)可觀察期纖維結構。TGA及DSC熱分析數據說明，隨著奈米碳管添加量的上升，其5%熱重損失溫度(Td)及玻璃轉移溫度(Tg)都有上升的趨勢，代表奈米碳管有助於複合材料熱穩定的趨勢。表面電阻的數據則是藉由表面電阻儀測試，隨著奈米碳管添加量的上升，而表面電阻是降低的。拉伸測試的結果顯示，拉伸強度及楊氏模數比較沒有規則性，而斷裂延伸率則是普遍逐漸下降。　　　　
　　生物相容性測試則是使用溶液成膜的方法製備，靜電紡絲製備成膜的部分，爾後再行測試。藉由全血凝固動力測試結果說明，有加入奈米碳管的PU複合材料之吸光值比未加入碳管的純PU和改質PU高，顯示出加入奈米碳管之後，可讓血液在薄膜上面不易凝固，增加抗凝血性，達到生物相容的效果。細胞毒性測試是使用MTT Test，由MTT結果顯示，可說明其溶液成膜的薄膜可能具有毒性。

　　In this research, the poly(tetramethylene oxide) (PTMO, M.W. = 2900) and the 4,4 '- diphenylmethane diisocyanate (MDI) with a molar ratio of 1:3 were reacted at 60-70 oC in nitrogen atmosphere to form the prepolymer(pre-PU). The product was subsequently added the 1,4 - butanediol (1,4-BD) and the N-BOC-protected serinol (N-BOC-serinol) to obtain the modified polyurethane (4PU). The N-BOC groups were deprotected from the 4PU by using the trifluoroacetic acid to obtain the serinol-modified PU. The multi-walled carbon nanotubes (MWCNTs) were calcined at 570 oC to remove the amorphous carbon and metals, and then H2SO4 and HNO3 at a ratio of 3/1 vol were added and reacted at 60 oC for 6 hours to get the COOH-functionalized MWCNTs (AMWCNTs). The AMWCNTs were chloroacylated by SOCl2 at 70-80 oC under N2 atmosphere to produce the COCl-functionalized MWCNTs (ClMWCNTs). Finally, the serinol-modified PU, ClMWCNTs (or AMWCNTs), and 4-dimethylaminopyridine (DMAP) were mixed and electrospun onto the aluminum foil. The electrospun web (or film) was then heated in vacuum at 70℃ for 24 hours in order to get the chemically bonded composite.
　　Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopic were used to identify the chemical structures of the PU/AMWNTs and PU/ ClMWNTs composites. The structure of the web was investigated by SEM and the incorporation of the MWCNTs into the 4PU were also examed by TEM. The temperature of decomposition with 95% mass remained (Td) obtained from the thermogravimetric analysis (TGA) and the glass transition temperature (Tg) measured by the differential scanning calorimetry (DSC) increased with the increase of the amount of the MWCNTs in the composite. The surface resistance of the composite decreased with the addition of the MWCNTs into the 4PU. The elongation at break of the specimen decreased with an increase in the amount of the MWCNTs in the composite.　
　　Biocompatibility was based on the whole blood clotting tests and the cell viability tests (MTT tests). The results showed that the anticoagulation ability of MWCNTs/PU was better than those of PU and 4PU. The cell viability tests indicated that PU, 4PU and the MWCNTs/PU composite were toxic to cells.

目 錄
摘 要 i
ABSTRACT iii
誌 謝 v
目 錄 vi
表目錄 x
圖目錄 xi

第一章 緒論 1
1.1前言 1
1.2研究動機與目的 2
1.3研究方法 2

第二章 文獻回顧 4
2.1聚胺酯 4
2.1.1聚胺酯簡介 4
2.1.2聚胺酯的合成 5
2.2奈米碳管 6
2.2.1奈米碳管簡介 6
2.2.2奈米碳管的改質 7
2.3 靜電紡絲 7
2.3.1靜電紡絲簡介 7
2.3.2靜電紡絲原理 8
2.3.3靜電紡絲影響因子…………………………………………………………..9
　2.4形狀記憶聚合物……………………………………………………………..…12
2.4.1形狀記憶性之聚合物介紹………………………………………………….12
2.4.2形狀記憶聚合物原理……………………………………………………….13
2.5聚胺酯/奈米碳管複合材料相關文獻 15

第三章 實驗 19
3.1 實驗藥品 19
3.2 實驗器材 25
3.3 實驗流程..………………………………………………………………………28
3.4 實驗儀器及檢測方法 29
3.4.1傅立葉轉換紅外線光譜法(Fourier Transform Infrared Spectroscopy，FTIR) 29
3.4.2核磁共振光譜法(Nuclear Magnetic Resonance Spectroscopy，NMR) 29
3.4.3凝膠滲透層析法(Gel Permeation Chromatography，GPC) 29
3.4.4掃描式電子顯微法(Scanning Electron Microscopy，SEM)……………….30
3.4.5穿透式電子顯微法(Transmission Electron Microscopy，TEM)…………...30
3.4.6熱重分析(Thermogravimetric Analysis，TGA) 30
3.4.7示差掃描熱分析儀(Diffterential Scanning Calorimetry，DSC) 31
3.4.8拉伸試驗(Tensile Test) 31
3.4.9粒徑分析儀(Quasielastic Light Scatteing) 32
3.4.10超絕緣儀(Super Megohmmeter) 32
3.4.11反滴定法(Boehm’s Method) 32
3.4.12全血凝固動力實驗(Whole Blood ClottingTest)…………………………..32
3.4.13細胞毒性測試(MTT Test)…………………………………………………33
3.4.14形狀記憶測試 (Shape Recovery Test )…………………………………...33
3.5 奈米碳管的純化與改質 36
3.5.1奈米碳管的純化 36
3.5.2奈米碳管的酸化…………………………………………………………….36
3.5.3奈米碳管的氯醯化………………………………………………………….37
3.6聚胺酯的製備……………….…………………………………………………..38
3.6.1藥品前處理 38
3.6.2聚胺酯的合成 38
3.6.3改質聚胺酯的合成 38
3.6.4改質聚胺酯的活化………………………………………………………….39
3.7 靜電紡絲改質聚胺酯/多壁奈米碳管複合材料的製備……………………….39

第四章 結果與討論 41
4.1 改質奈米碳管鑑定 41
4.1.1粒徑分析 41
4.1.2官能基鑑定(反滴定法) 41
4.1.3 FTIR分析 42
4.2 改質聚胺酯/多壁奈米碳管複合材料鑑定 43
4.2.1 FTIR分析 43
4.2.2 1H NMR分析 46
4.2.3 GPC分析 50
4.2.4 SEM纖維之觀察...…………………………………………………………51
4.2.5 TEM纖維內部之觀察……………………………………………………...56
4.2.6 DSC分析 72
4.2.7 TGA分析 75
4.2.8機械性質分析 77
4.2.9表面電阻 81
4.2.10形狀記憶恢復測試 84
4.3生物相容性測試（Casting Film）………………………………………………87
4.3.1全血凝固動力試驗（Casting Film）……………………………………….87
4.3.2 MTT測試（Casting Film）…………………………………………………89

第五章 結論 91
參考文獻 93
附錄A 奈米碳管粒徑分析數據 98
附錄B 聚胺酯、改質聚胺酯及複合材料之FTIR圖譜 101
附錄C 聚胺酯、改質聚胺酯及複合材料之NMR圖譜 105
附錄D 聚胺酯、改質聚胺酯及活化聚胺酯之GPC 109
附錄E 聚胺酯、改質聚胺酯及活化聚胺酯之SEM…………………………………113
附錄F 聚胺酯、改質聚胺酯及複合材料之DSC 118
附錄G 聚胺酯、改質聚胺酯及複合材料之TGA 125
附錄H 聚胺酯及複合材料之機械性質數據 132
附錄I 聚胺酯、改質聚胺酯及複合材料之表面電阻測試數據 135
附錄J 聚胺酯、改質聚胺酯及複合材料之形狀記憶性測試數據 137
附錄K聚胺酯、改質聚胺酯及複合材料(Casting Film)之全血凝固動力測試數據139
附錄L聚胺酯、改質聚胺酯及複合材料(Casting Film)之MTT測試數據…………..142、表目錄
表2.1 HBPU/MWCNTs複合材料之機械性質數據[36] ……………………………..15
表2.2 PU與MWCNTS/PU之機械性質數據表[38]…………………………..……...17
表2.3 PU、SWCNTs-PU、MWCNTs-PU之纖維薄膜之導電度[40]………………..17
表2.4奈米碳管/形狀記憶性聚胺酯之記憶型的測試數據[41]……………………...18
表3.1 聚胺酯(PTMO=2900)與改質聚胺酯配製參數………………………............. 39
表3.2 複合材料製備參數(以配製10ml，20wt%高分子溶液為例)………………..40
表4.1酸化奈米碳管反滴定結果 …42
表4. 2改質聚胺酯/多壁奈米碳管複合材料之FTIR共振峰值表……………………45
表4. 3 PU、4PU和活化4PU之硬鏈段氫鍵鍵結指數(R) ………………………….45
表4. 4 PU及4PU之GPC數據 50
表4. 5 PU、改質4PU、複合材料之Tg數據………………………………………...73
表4. 6 PU、改質4PU、複合材料之TM數據 73
表4. 7 PU、改質4PU、複合材料之AREA數據 .74
表4. 8 PU、改質4PU、鍵結及混摻複合薄膜材料之Td點與殘餘量數據…………76
表4. 9 PU、混摻及鍵結複合薄膜材料之抗拉強度…………………………………..78
表4. 10 PU、混摻及鍵結複合薄膜材料之楊氏模數…………………………………79
表4. 11 PU、混摻及鍵結複合材料之斷裂延伸率 80
表4. 12 PU、改質4PU及混摻與鍵結複合薄膜材料之表面電阻數據 82
表4. 13 PU、改質4PU、混摻與鍵結複合薄膜材料之形狀保持率數據 85
表4. 14 PU、改質4PU、混摻與鍵結複合薄膜材料之形狀回復率數據……………86
表4. 15 PU、改質4PU與MWCNTS/PU全血凝固動力試驗之吸收值(OD570)數據….. 87
表4. 16 PU、改質4PU、MWCNTs/PU之MTT(0天)測試數據……………………89
表4. 17 PU、改質4PU、MWCNTs/PU之MTT(1天)測試數據……………………90、圖目錄
圖2. 1 聚胺酯之結構[7] 5
圖2. 2 聚胺基甲酸酯之相分離圖[8-9].………………………...……………………...5
圖2. 3 二段聚合法[12-13]…………………………...…………………………………6
圖2. 4 (a)單壁奈米碳管 (b)多壁奈米碳管 之奈米碳管結構[14]................................6
圖2. 5亞硫醯氯官能基改質之流程[18] 7
圖2. 6靜電紡絲裝置 9
圖2. 7 (A)分子量1000之PU之SEM影像(B)分子量2900之PU之SEM影像…...9
圖2. 8 (A)分子量1000之2PU之SEM影像(B)分子量2900之4PU之SEM影像...10
圖2. 9 (A)分子量1000之2PU3之SEM影像(B)分子量2900之4PU3之SEM影像..10
圖2. 10 PDLA溶液濃度不同對纖維形態影響(a) 25wt%(b) 30 wt% (c)35wt%[26]...10
圖2. 11靜電紡絲參數對纖維的影響之總整理[29]…………………………………..11
圖2. 12製備聚胺酯之過程圖[34] ………………………………………………….....13
圖2. 13聚胺酯之形狀恢復率與硬鏈段比例之關係圖[34]…………………………..13
圖2. 14形狀記憶性原理[35]…………………………………………………………..14
圖2. 15 HBPU/MWCNTS複合材料的熱裂解溫度[36] ……………………………...15
圖2. 16 PU與不同含量之奈米碳管複合薄膜材料之TEM影像[37]……………….16
圖3. 1以ASTM D412-C型裁刀裁切樣品之樣品圖 ……………………………..…31
圖3. 2形狀記憶測試實驗流程圖……………………………………………………..36
圖3. 3奈米碳管純化與改質流程圖…………………………………………………..37
圖4. 1 (A)市售奈米碳管(B)AMWCNTS (C)ClMWCNTS之FTIR光譜圖………………..42
圖4. 2 (A)PU (B)4PU (C)活化4PU (D)4PU3複合材料 之FTIR光譜圖 44
圖4. 3 (A)PU (B)4PUA3複合材料之FTIR光譜圖 44
圖4. 4 PU之1H NMR圖譜 47
圖4. 5 改質4PU之1H NMR圖譜 48
圖4. 6 活化4PU之1H NMR圖譜 48
圖4. 7 4PU3複合材料之1H NMR圖譜 49
圖4. 8 4PUA3複合材料之1H NMR圖譜 49
圖4. 9 PPU之SEM影像………………………………………………………………51
圖4. 10 4PU之SEM影像…..…………………………………………………………52
圖4. 11 4PUA1之SEM影像…………………………………………………………..52
圖4. 12 4PUA3之SEM影像…………………………………………………………..53
圖4. 13 4PUA5之SEM影像…………………………………………………………..53
圖4. 14 4PU1之SEM影像….………………………………………………………..54
圖4. 15 4PU3之SEM影像….………………………………………………………..54
圖4. 16 4PU5之SEM影像….………………………………………………………..55
圖4. 17 4PU1之20K TEM影像….…………………………………………………..57
圖4. 18 4PU1之50K TEM影像.……………………………………………………..58
圖4. 19 4PU1之100K TEM影像..……………………………………………………59
圖4. 20 4PU3之20K TEM影像..……………………………………………………..60
圖4. 21 4PU3之50K TEM影像..……………………………………………………..61
圖4. 22 4PU3之100K TEM影像..……………………………………………………62
圖4. 23 4PU5之20K TEM影像..……………………………………………………..63
圖4. 24 4PU5之50K TEM影像..……………………………………………………..64
圖4. 25 4PU5之100K TEM影像..……………………………………………………65
圖4. 26 4PUA3之20K TEM影像……………………………………………………..66
圖4. 27 4PUA3之50K TEM影像……………………………………………………..67
圖4. 28 4PUA3之100K TEM影像…..……………………………………………….68
圖4. 29 4PUA5之20K TEM影像……………………………………………………..69
圖4. 30 4PUA5之50K TEM影像……………………………………………………..70
圖4. 31 4PUA5之100K TEM影像..………………………………………………….71
圖4. 32混摻與鍵結複合薄膜材料之Tg與碳管添加量之比例關係圖.……………73
圖4. 33混摻與鍵結複合薄膜材料之Tm與碳管添加量之比例關係圖.…………...74
圖4. 34混摻與鍵結複合薄膜材料之Area與碳管添加量之比例關係圖……………74
圖4. 35鍵結及混摻複合薄膜材料之Td點與奈米碳管添加量之關係圖.…………76
圖4. 36混摻及鍵結複合薄膜材料之抗拉強度與碳管添加量之比例關係圖..……..78
圖4. 37混摻及鍵結複合薄膜材料之楊氏模數與碳管添加量之比例關係圖 79
圖4. 38混摻及鍵結複合薄膜材料之斷裂延伸率與碳管添加量之比例關係圖……80
圖4. 39混摻複合薄膜材料之電阻與奈米碳管添加量之比例關係圖………………82
圖4. 40鍵結複合薄膜材料之電阻與奈米碳管添加量之比例關係圖………………83
圖4. 41混摻與鍵結之複合薄膜材料之電阻與奈米碳管添加量之比例關係圖……83
圖4. 42 PU、混摻與鍵結複合薄膜材料之形狀保持率與奈米碳管添加量之關係圖.85
圖4. 43 PU、混摻與鍵結複合薄膜材料之形狀回復率與奈米碳管添加量之關係圖.86
圖4. 44 PU、改質4PU與MWCNTs/PU全血凝固動力試驗之比較圖…………….88
圖4. 45 PU、改質4PU、MWCNTs/PU之MTT測試吸光值(0天)………………..89
圖4. 46 PU、改質4PU、MWCNTs/PU之MTT測試吸光值(1天)………………..90

[1]Cooley, J.F.British Patent GB 06385 「Improved methods of and apparatus for electrically separating the relatively volatile liquid component from the component of relatively fixed substances of composite fluids」.　
[2]Iijima, S. “Helical microtubules of graphitic carbon” Nature, vol.354, 1991, pp. 56.
[3]Collins P. G. , A. Zettl, H. Bando, A. Thess and R. E. Smalley, “Nanotube nanodevice” Science, vol. 278, 1977, pp. 100-103.
[4]Sen, R., B Zhao., Perea, D., Itkis, M.E., Hu, H., Love, J.,Bekyarova, E.Haddon, R.C. “Preparation of single-walled carbon nanotube reinforced polystyrene and polyurethane nanofibers and membranes by electrospinning” Nano Letters, vol.4 , 2004 , pp.459-464.
[5]David D. J. and H. B. Staley, “Analytical Chemistry of the Polyurethanes Part III”, New York, Wiley-Interscience, 1969.
[6]Boretos, J.W., Pierce,W. S. “Segmented polyurethane : a new elastomer for biomedical applications. ” Science , vol.158 , 1967 , pp.1481-1482.
[7]黃凌威，紫外光可硬化聚胺酯丙烯酸樹脂之製備與其應用於高透明防破裂玻璃保護之研究，碩士論文，國立台灣大學化學工程學研究所，臺北市，2009.
[8]林睿哲，聚胺基甲酸酯之磺酸化改質與蛋白質前吸附處理於人工膽管支架之膽汁相容性探討，碩士論文，國立成功大學化學工程學系，台南市，2003.
[9]Chen, K.S., Yu, T.L., Chen, Y.S., Lin, T.L.,Liu, W.J. “Soft- and hard-segment phase segregation of polyester-based polyurethane” Journal of Polymer Research , vol.8 , 2001 , pp.99-109.
[10]M. D. Lelah and S. L. Cooper, “Polyurethane Chemistry.” in “Polyurethane in Medicine” CRC Press, Boca Raton, FL, USA,1986.
[11]Chang A. L. and E. L. Thomas, “Morphological studies of PCL/MDI/BDO-based segmented polyurethanes” Advances in Chemistry Series, vol. 176, 1979, pp. 31-52.
[12]Hepburn C., “Polyurethane Elastomers” Applied Science, London, 1982.
[13]Oertel G., “Polyurethane Handbook” New York, Hanser Publisher, 1985.
[14]魏向辰，導電高分子與多層奈米碳管複合材料之研究，國立中央大學化學
與材料工程研究所，2007.
[15]Tsang, S. C., Y. K, Chen., P. J. F, Harris., M. L. H, Green., “A simple chemical method of opening and filling carbon nanotubes” Nature , vol.372 , 1994 , pp.159-162.
[16]Liu, J., A.G, Rinzler., H, Dai., J.H, Hafner., K Bradley, R., Boul, P.J., Lu, A., Iverson, T., Shelimov, K., Huffman, C.B., Rodriguez-Macias, F., Shon, Y.-S., Lee, T.R., Colbert, D.T., Smalley, R.E., “Fullerene pipes”, Science, vol.280 , 1998 , pp.1253-1255.
[17]Chen J., M. A. Hamon, H. Hu, Y. Chen, A. M. Rao, P. C. Eklund and R. C. Haddon, “Solution properties of single-walled carbon nanotubes” Science, vol. 282, 1998, pp. 95-98.
[18]Hamon M. A., J. Chen, H. Hu, Y. Chen, A. M. Rao, P. C. Eklund and R. C. Haddon, “Dissolution of single-walled carbon nanotubes” Advanced Material, vol. 11, 1999, pp. 834-840.
[19]Zeleny, J. The Electrical Discharge from Liquid Points, and a Hydrostatic Method of Measuring the Electric Intensity at Their Surfaces. Physical Review. 1914, 3 (2): 69.
[20]Formhals, A. US Patent No.2187306,1940.
[21]Formhals, A. US Patent No.2323025,1943.
[22]Taylor, G.I. “Disintegration of water drops in an electric field” Proceedings of The Royal Society A：Mathematical , Physical &; Engineering Sciences, vol.280 , 1964 , pp.383-397.
[23]Reneker , D. H., I, Chun. “Nanometre diameter fibres of polymer, produced
by electrspinning” Nanotechnology , vol.7 , 1996 , pp.216-223.
[24]潘彥曲，靜電紡絲製備醚型聚胺酯/改質奈米碳管複合材料及性質鑑定，碩士論文，臺北科技大學有機高分子所，臺北市，2013.
[25]Zong, X., K, Kim., D, Fang., S, Ran., B.S, Hsiao ., B, Chu., “Structure and process relationship of electrospun bioabsorbable nanofiber membranes” Polymer , vol.43 , 2002 , pp.4403-4412.
[26]Mit-Uppatham, C., M Nithitanakul., P, Supaphol., “Ultrafine electrospun polyamide-6 fibers: Effect of solution conditions on morphology and average fiber diameter” Macromolecular Chemistry and Physics , vol.205 , 2004 , pp.2327-2338.
[27]Wang, C., W, Zhang., Z. H, Huang., E. Y, Yan., Y. H, Su., “Effect of concentration, voltage, take-over distance and diameter of pinhead on precursory poly (phenylene vinylene) electrospinning” Pigment and Resin Technology , vol.35 , 2006 , pp.278-283.
[28]Buchko, C.J., L. C, Chen., Y Shen., D. C, Martin., “Processing and microstructural characterization of porous biocompatible protein polymer thin films” Polymer , vol. 40 , 1999 , pp.7397-7407.
[29]Yuan, X.Y., Y. Y, Zhang., C, Dong., J, Sheng., “Morphology of ultrafine polysulfone fibers prepared by electrospinning” Polymer International , vol.53 , 2004 , pp.1704-1710.
[30]Buehler W. J., J. V. Gilfrich and R. C. Wiley, “Effect of low-temperature phase changes on the mechanical properties of alloys near composition TiNi” Journal of Applied Physics, vol. 34, 1963, pp. 1475-1477.
[31]王學樑，奈米銀/形狀記憶聚胺基甲酸酯功能性複合材料製備與形狀記憶性影響之研究，華岡工程學報，中國文化大學工程學院，台北市，2007.
[32]林志榮，聚氨酯形狀記憶材料及其機械黏彈模型，國立台灣大學材料科學與工程學研究所，博士論文，台北市，1998.
[33]Lee B. S., B. C. Chun, Y. C. Chung, K. I. Sul and J. W. Cho, “Structure and thermomechanical properties of polyurethane block copolymers with shape memory effect” Macromolecules, vol. 34, no. 18, 2001, pp. 6431-6437.
[34]李宣緯，鄭如忠，「有記憶的高分子」，科學發展，第472期，2012，第13-14頁.
[35]Deka H., N. Karak, R. D. Kalita and A. K. Buragohain, “Biocompatible hyperbranched polyurethane/multi-walled carbon nanotube composites as shape memory materials” Carbon, vol. 48, 2010, pp. 2013-2022.
[36]Rana, S., J. W, Cho., “Core-sheath polyurethane-carbon nanotube nanofibers prepared by electrospinning” Fibers and Polymers , vol.12 , 2011 , pp.721-726.
[37]Tijing, L.D., C. H, Park., W. L, Choi., M. T. G, Ruelo., A, Amarjargal., H. R, Pant., I. T, Im., C. S, Kim., “Characterization and mechanical performance comparison of multiwalled carbon nanotube/polyurethane composites fabricated by electrospinning and solution casting” Composites Part B: Engineering , vol.22 , 2013 , pp.613-619.
[38]柯佩欣，2-胺基丙二醇改質醚型聚胺酯/多壁奈米碳管複合材料之製備、鑑定和形狀記憶性，碩士論文，臺北科技大學有機高分子所，臺北市，2014.
[39]Sirivisoot, S., B. S, Harrison., “Skeletal myotube formation enhanced by electrospun polyurethane carbon nanotube scaffolds.” International journal of nanomedicine , vol.6 , 2011 , pp.2438-2497.
[40]Bai, Y. K., Y. M, Zhang., and Q, Wang., “Shape memory properties of multi-walled carbon nanotube/polyurethane composites prepared by in situ polymerization” Journal of Materials Science, vol. 48, 2013, pp. 2207-2214.
[41]Meng, J., H, Kong., H. Y, Xu., L, Song., C. Y, Wang., S. S, Xie., “Improving the blood compatibility of polyurethane using carbon nanotubes as fillers and its implications to cardiovascular surgery” Journal of Biomedical Materials Research - Part A ,vol.74 , 2005 , pp.208-214.