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Synthesis and Characteristics of Poly(N-isopropylacrylamide-co-methacrylic acid)/Fe3O4 Thermosensitive Magnetic Composite Hollow Latex Particles
No full textSynthesis and Research of Termosensitive Magnetic Hollow Latex Particle
No full text摘要 本研究目的是利用無乳化劑乳化聚合法製備溫度敏感磁性中空乳膠顆粒，並將合成出的顆粒包覆藥物，進行各項測試。 本論文分三部份，第一部份：合成Poly(Methylmethacryl-Methyl acrylic acid)(poly(MMA-MAA))乳膠顆粒，並以此乳膠顆粒為seeds，再分別加入N-Isopropylacrylamide(NIPAAM)、Methyl acrylic acid(MAA)、交聯劑N,N’-Methylene-bisacrylamide(MBA)及起始劑Potassium persulfate(KPS)，形成外層有交聯結構的Poly(MMA-MAA)/poly(NIPAAM-MAA)乳膠顆粒。接者加入氨水，將顆粒內部無交聯的部份Poly(MMA-MAA)溶解出來，形成中空乳膠顆粒。在實驗中，改變殼層NIPAAM及MAA比例、MBA量，並以TEM觀察中空顆粒形態並探討其性質。 第二部份，我們利用具有羧酸基之中空乳膠顆粒Poly(NIPAAM-MAA)，加入鐵離子並與顆粒鍵結成-COOFe2+及-COOFe3+，當氨水參與反應時，Fe3O4將會以in-situ的方式形成。針對不同殼層比例並改變磁流形成環境的pH值、溫度及磁流添加量，由TEM圖觀察磁性乳膠顆粒上磁流的分布及性質。 第三部份，選出上述步驟中，磁流分佈較均勻的磁性中空乳膠顆粒為seeds，再添加NIPAAM、MAA、MBA及KPS形成Poly(NIPAAM-MAA)/Fe3O4/Poly(NIPAAM-MAA)中空磁性乳膠顆粒，改變seeds濃度、NIPAAM、MAA及MBA量，並進行LCST及TEM的測試與觀察。最後，利用紫外光-可見光分光光度計在272nm，於不同時間下取樣測試咖啡因濃度-藥物包覆釋放實驗，並討論不同pH值、不同溫度下包覆效果。鍵字：氮-異丙基丙烯醯胺，甲基丙烯酸，中空乳膠顆粒，磁性，藥物釋放Abstract We synthesis magnetic hollow latex with the behaviors of thermosensitivity by the method of soapless emulsion polymerization. We tests this magnetic hollow latex in some experiments including TEM, LCST and drug release. First, We synthesis the linear copolymer,poly(methyl methacrylate-methyl acrylic acid)(Poly(MMA-MAA)). Using it as seeds, we add different ratio of NIPAAM(N-isopropylacrylamide)/MAA(methacrylic acid) and amount of crosslinker to synthesis Poly(MMA-MAA) /(NIPAAM-MAA). Then we use ammonium hydroxide to dissolve Poly(MMA-MAA) inside of the particle to get hollow P(NIPAAM-MAA) latex which is thermo-sensitive. We use transmission electron microscopy to observe hollow Poly(NIPAAM-MAA) latex. Second, by using the functional group (-COOH) on hollow latex surface to bond with Fe2+and Fe3+, we put ammonia into the latex, and get magnetic hollow latex. The effects of temperature, amount of Fe3O4, and ratio of NIPAAM/MAA on in-situ reaction were investigated. Third, using magenetic hollow latex as seeds, we add different ratio of NIPAAM/MAA and amount of crosslinker to synthesis Poly(NIPAAM-MAA)/Fe3O4/(NIPAAM-MAA) magnetic hollow latex. The magnetic hollow latex containing thermo-sensitive monomers can be used in drug releasing treatment. We observe drug release of magenic hollow latex in different temperature and buffer solution by UV-vis Spectrophotometer.eyword: N-isopropylacrylamide, acrylic acid, hollow latex, magnetic, drug release目 錄要............................................................................................................. Ibstract ......................................................................................................II 錄.......................................................................................................III 目 錄................................................................................................. VII 目 錄................................................................................................. XII一章 緒論...............................................................................................1-1 氧化鐵.................................................................................................2-2 磁性材料.............................................................................................3-3 磁性流體的製造.................................................................................3-4 乳化聚合.............................................................................................5-4-1 簡介...........................................................................................5-4-2 無乳化劑乳化聚合...................................................................6-5 免疫乳膠顆粒的製備.........................................................................7-6 標的導向型藥物功能.........................................................................8-6-1 控制藥物標定導向...................................................................8-6-2 控制藥物釋放傳輸...................................................................9-7 中空高分子顆粒製備方式...............................................................12三章 實驗方法....................................................................................15-1 實驗藥品與儀器...............................................................................15-1-1 實驗藥品................................................................................15-1-2 實驗儀器................................................................................15-2 實驗流程...........................................................................................20-2-1 Poly(MMA-MAA)乳膠顆粒之合成......................................20-2-2 Poly(MMA-MAA)/(MAA-NIPAAM)乳膠顆粒之合成........20V-2-3 中空(MAA -NIPAAM)乳膠顆粒之合成...............................21-2-4 Poly(MAA-NIPAAM)/Fe3O4 磁性中空乳膠顆粒之合..............................................................................................21-2-5 Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)中空型磁性膠顆粒之合成.............................................................22-3 合成方法...........................................................................................23-3-1 Poly (MMA- MAA)乳膠顆粒之合成................................23-3-2 Poly(MAA- MMA)/(NIPAAM- MAA)乳膠顆粒之合成......24-3-3 中空Poly(MAA -NIPAAM)乳膠顆粒之合成.......................25-3-4 Poly (MAA-NIPAAM)/Fe3O4磁性中空乳膠顆粒之合成.....26-3-5 Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)中空型磁性膠顆粒之合成.....................................................................27-3-6 代號說明.................................................................................28-4 性質測定............................................................................................30-4-1 顆粒形態之觀察-TEM……………………………………...30-4-2 顆粒形態之觀察-TEM 切片圖.............................................30-4-3 LCST 測試實驗.......................................................................30-4-4 熱重損失分析儀測試(TGA)..................................................30-4-5 磁滯曲線測試.........................................................................30-4-6 轉化率測定.............................................................................30-4-7 藥物包覆釋放測試.................................................................32四章 結果與討論................................................................................34-1 Poly (MMA- MAA) 乳膠顆粒之合成..............................................35-1-1 轉化率測定............................................................................35-1-2 Poly(MMA-MAA)乳膠顆粒的形態觀察..............................35-2 Poly (MMA- MAA)/(MAA-NIPAAM)乳膠顆粒之合成.................36-2-1 轉化率測定.............................................................................36-2-2Poly(MMA-MAA)/(MAA-NIPAAM) 顆粒的形態觀............................................................................................37-3 Poly (MAA-NIPAAM)中空乳膠顆粒之合成...................................38-3-1 Poly (MAA-NIPAAM)中空乳膠顆粒之形態觀察................38-3-2 Poly (MAA-NIPAAM)中空乳膠顆粒之LCST 測定............38-4 Poly (MAA-NIPAAM)/ Fe3O4 中空磁性乳膠顆粒之合成..............39-4-1 不同單體比例對Poly (MAA-NIPAAM)/ Fe3O4中空磁性乳膠粒的形態影響....................................................................39-4-2 不同交聯度對Poly (MAA-NIPAAM)/ Fe3O4中空磁性乳膠顆amp;#63993;的形態影響........................................................................39-4-3 不同磁流量對Poly (MAA-NIPAAM)/ Fe3O4中空磁性乳膠顆amp;#63993;的形態影響.........................................................................39-4-4 不同溫度對Poly (MAA-NIPAAM)/ Fe3O4 中空磁性乳膠顆amp;#63993;的形態影響.........................................................................40-4-5 不同pH 值對Poly (MAA-NIPAAM)/ Fe3O4中空磁性乳膠顆amp;#63993;的形態影響........................................................................40-4-6 Poly (MAA-NIPAAM)/ Fe3O4 中空磁性乳膠顆粒之LCST 測............................................................................................41-4-7 Poly (MAA-NIPAAM)/ Fe3O4中空磁性乳膠顆粒之磁滯曲線定........................................................................................42-4-8 Poly (MAA-NIPAAM)/ Fe3O4 中空磁性乳膠顆粒之TGA 測............................................................................................43-5 Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)中空型磁性乳膠顆Iamp;#63993;之合成...........................................................................................44-5-1 合成Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)中空型性乳膠顆粒的形態觀察.....................................................44-6 Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)中空型磁性乳膠顆amp;#63993;藥物釋放實驗............................................................................47-6-1 caffeine calibration curve 之建立...........................................47-6-2 載藥後之形態觀察................................................................47-6-3 載藥測試................................................................................47-6-4 藥物釋放測試........................................................................48五章 結論.............................................................................................49amp;#63851;考文獻...................................................................................................50 目 錄2-1鐵氧化物結構簡表………………………………………………..23-3-1 Poly(MMA-MAA)乳膠顆粒之進料組成與反應條件...........233-3-2 Poly(MAA-MMA)/(NIPAAM-MAA)乳膠顆粒之進料組成與反應條件...................................................................................................243-3-3中空Poly(MAA -NIPAAM)乳膠顆粒之進料組成與反應條件...............................................................................................................253-3-4 Poly (MAA-NIPAAM)/Fe3O4磁性中空乳膠顆粒之進料組成與反應條件...................................................................................................263-3-5 Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)中空型磁性乳膠顆粒之進料組成與反應條件...............................................................273-3-6 Poly (MAA-NIPAAM)/Fe3O4/(MAA-NIPAAM)乳膠顆粒第二次包殼組成之代號整理...........................................................................293-4-1 Poly(MMA-MAA)乳膠顆粒之進料組成...............................313-4-2 Poly(MAA-MMA)/(NIPAAM-MAA)乳膠顆粒之進料組成....324-1轉化率與反應時間對照表.............................................................344-2-1 不同MAA、NIPAAM比例與反應時間的轉化率對照表........354-2-1 不同MAA與NIPAAM比例與反應時間的轉化率對照表(continued) ...............................................................................................364-2-2不同組成的Poly(MMA-MAA)/(MAA-NIPAAM)乳膠顆粒的粒徑對照表...............................................................................................374-3-2不同組成的Poly (MAA-NIPAAM)乳膠顆粒的LCST對照表..................................................................................................................384-4-6不同合成環境的Poly (MAA-NIPAAM)/ Fe3O4中空磁性乳膠顆粒LCST對照表...................................................................................414-6藥物釋放量....................................................................................4
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use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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