聚丙基丙烯醯胺poly(N-isopropyl acrylamide)(poly(NIPAM))的化學結構式具有疏水性的主鏈及親水性的支鏈。由於其特殊的化學結構造成它的分子形態對溫度變化有極大的敏感性，會隨著溫度的上升下降有可逆的物理形態變化。
本論文研究poly(NIPAM)水溶液濃度是1wt%及2wt%應屬於半稀釋溶液(semi-dilution solution)。分形維數及動態光散射數據均顯示兩者的θ-Temp在30℃附近。在溫度低於θ-Temp時poly(NIPAM)經由水分子氫鍵產生交聯形成網狀結構，分形維數dF＞2.2以上。在溫度高於θ-Temp時氫鍵解離分子鏈伸展而排列鬆散，dF＜2.0以下。在溫度高於33℃以上水分子與poly(NIPAM)之間的氫鍵完全解離，poly(NIPAM)與水互不相溶，產生²相²分離(phase separation)無法做光散射實驗。2wt% poly(NIPAM)水溶液濃度較高，在溫度低於θ-Temp時poly(NIPAM)分子經由水分子氫鍵聚集形成分子團(cluster)。但1wt% poly(NIPAM)水溶液，分子團含量較少。動態光散射fast mode Rf值在半稀釋溶液中是量測分子鏈相鄰兩交聯點或重疊點間的距離。在溫度高於θ-Temp以上，因氫鍵解離且分子鏈伸張造成Rf在30℃以上，隨溫度上升而增加。當poly(NIPAM)濃度增加時，分子鏈的氫鍵交聯及重疊點增加，相鄰兩交聯點或重疊點間距離縮短，Rf下降。所以2wt% poly(NIPAM)溶液的Rf值低於1wt% poly(NIPAM)水溶液的Rf值。

Poly(NIPAM) has a chemical structure hydrophobic main chain and hydrophibic side chains. Molecular chain conformation of poly(NIPAM) are sensitive with temperature due to special chemical structure that has reversible physical conformation with temperature. In this study poly(NIPAM) solution concentration are 1wt% and 2wt% that belong to semi-dilution solution. Fractal dimension and DLS data show a θ-temp of about 30℃. At a temperature lower thanθ-temperature Poly(NIPAM) formed network structure through crosslink of H2O H-bond with fractal dimension dF>2.2. At a temperature higher thanθ-temperature, H-bond decompose and molecular chains expand causing a loose molecular chain arrangement and fractal dimension below dF<2.0. Above 33℃, H-bond decompose completely, poly(NIPAM) and water causes “phase” separation. In 2wt% poly(NIPAM) water solution, poly(NIPAM) molecules aggregate to form cluster through H-bond aggregation. But as poly(NIPAM) concentration was reduced to 1wt% very few clusters were observed. In the DLS experiments, Rf value measures distance between two neighbouring crosslink points or overlap points. Above θ-temp, H-bond decomposed and molecular chain expanded caused Rf value to increase with temperature. When poly(NIPAM) concentration increased, H-bond crosslinks and molecular chain overlap points increased, distance between neighbouring crosslink points or overlap points decreased and Rf decrease. So the Rf value of 2wt% poly(NIPAM) water solution is lower than that of 1wt%.

中文摘要…………………………….…………………………i
英文摘要……………………………………………………….ii
致謝…………………………………………………………….iv
目錄……..………………………………………………………v
表目錄 ………………………………………………………...vii
圖目錄 ……………………………………………….……….viii
第一篇 Poly(NIPAM)水溶液的光散射研究
一、前言……………………………………………………....1
1.1簡介……………………………………………………1
1.2研究目的………………………………………….....…5
二、實驗方法…………………………………………………..6
2.1材料………………………………………….………..6
2.2溶液配置……………………………………….…..…6
2.3儀器及器材規格……………………...………….…...6
2.4實驗方法……………………………………….……..9
2.4.1分形維數實驗………………………………………9
2.4.2動態光散射儀器操作………………………………9
2.5數據分析……………………………………………...9
2.5.1分形維數數據分析…………………………………9
2.5.2動態光散射數據分析……………………………..10
三、結果與討論……………………………………………....15
3.1光散射實驗………………………………………….15
3.1.1 Poly(NIPAM)水溶液之分形維數探討…...……..…15
3.1.2 動態光散射實驗…….………………………...…..17
3.1.3 討論…….………………………...…..…….………20
四、討論………………………………………………..... 22
五、參考文獻…………………………………………….... 23

Aronson M., Lock M., Santos E., “Encapsulated bleach particles for machine dishwashing compositions”, US Patent, 4, 762, 637 (1988)
Bae Y.H., Okano T., Kim S.W., “²on-off² thermocontrol of solute transport. I. Temperature dependence of swelling of N-isopropylacrylamide networks modified with hydrophobic components in water”, Pharm. Res., 8, 531 (1991)
Deshmukh M.V., Ganapathy S., Kulkarni M.G., Rajamohanan P.R., Vaidya A.A., “LCST in poly(N-isopropylacrylamide) copolymers:hight resolution proton NMR investigation”, Polymer, 41, 7951-7960 (2000)
Deshmukh M.V., Ganapathy S., Kulkarni M.G., Rajamohanan P.R., Vaidya A.A., “Proton magnetic resonance imaging in hydrogels:Volume phase transition in poly(N-isopropylacrylamide)”, Polymer, 41, 4543-4547 (2000)
Dong L.C., Hoffman A.S., “Synthesis and application of thermally-reversible heterogels for drug delivery”, J. Controlled Release, 14, 21 (1990)
Dong L.C., Hoffman A.S., “A novel approach for preparation PH-sensitive hydrogels for enteric drug delivery”, J. Controlled Release, 15, 141 (1991)
Durmaz S., Okay O., “Phase separation during the formation of poly(acrylamide) hydrogels”, Polymer, 41, 5729-5735 (2000)
Fang L., Brown W., “Dynamic light scattering by permanent gels: Heterodyne and nonergodic medium methods of data evalution”, Macromolecules, 25, 6897 (1992)
Fujishige,S., “Intrinsic viscosity-molecular weight relation for poly(N-isopropylacrylamide) solution:, Polym. J.,19, 297(1987)
Fujishige S., Kubota K., Ando I., “Single-chain transition of poly(N-isopropylacrylamide) in water”, J. Phys. Chem., 93, 3311 (1990)
Garay M.T., Alava C., Rodriguez M., “Study of polymer-polymer complexes and blends of poly(N-isopropylacrylamide) with poly(carboxylic alcohol) 2.poly(acrylic acid) and poly(methacrylic acid) partially neutralized”, Polymer, 41, 5799-5807 (2000)
Geissler E., Horkay F., Hecht, A-M., “Osmotic and scattering properties of chemically cross-linked poly(vinyl alcohol) hydrogels”, Macromolecules, 24, 6006 (1991)
Hansen J.P., Levesque D., Zinn-Justin J., “Liquids,freezing and glass transition”, North-Holland:Amsterdam,Neth, 488 (1991)
Hatto N., Cosgrove T., Snowden M.J., “Novel microgel-particle colloids:The detailed characterization of the layer structure and chain topology of silica: Poly(N-isopropylacrylamide) core-shell particles”, Polymer, 41, 7133-7137 (2000)
Henkel C., European Patent Application DE-636904 (1986)
Hoffman A.S., Dong L.C., “A general classification scheme for ²hydrophilic² Am. Chem. Soc. Symp. Ser., 350, 236 (1987)
Horkay, F., Burchard, W., Geissler, E., and Hecht, A-M., “Thermodynamic properties of poly(vinyl alcohol) and poly(vinyl alcohol-vinyl acetate) hydrogels”, Macromolecules, 26, 1296 (1993-a).
Horkay, F., Burchard, W., Hecht, A-M., and Geissler, E., “Scattering properties of poly(vinyl acetate) gels in different solvents”, Macromolecules, 26, 4203 (1993-b).
Hsu S.H., Yu T.L., “Recentrant behavior of poly(vinyl alcohol)-borax semidilute aqueous solutions”, Macromol. Rapid Commun.,21, 476 (2000)
Itakura M., Inomata K., Nose T., “Aggregation behavior of poly(N,N-diethylacrylamide) in aqueous solution”, Polymer, 41, 8681-8687 (2000)
Joosten J.G.H., Gelade E.T.F., Pusey P.N., “Dynamic light scattering by nonergodic media:Brownian particles trapped in polyacrylamide gels”, Phys. Rev. A., 42, 2161(1990)
Joosten J.G.H., McCarthy J.L., Pusey P.N., “Dynamic and static light scattering by aqueous polyacrylamide gels”, Macromolecules, 24, 6690 (1991)
Kubota K., Fujishige S., Ando I., “Phase transition of aqueous solution of poly(N-isopropylacrylamide) and poly(N-isopropylacrylamide)”, J. Phys. Chem. 94, 5154(1989)
Kubota K., Fujishige S., Ando I., “Solution properties of poly(N-isopropylacrylamide) in water”, Polym. J. 22(1), 1520(1990)
Lion C., Japanese Patent, 149, 691 (1984)
Melekaslan D., Okay O., “Swelling of strong polyelectrolyte hydrogels in polymer solutions:Effect of ion pair formation on the polymer collapse”, Polymer, 41, 5737-5747 (2000)
Mitsuhiro S., Toyoichi T., J. Chem. Phys. 102, 23 (1995)
Mitsuhiro S., Yoshihiro F., Shumji N., “Dynamic light scattering study of poly(N-isopropylacrylamide-co-acrylic acid) gels”, Macromolecules, 29, 6535 (1996)
Okano T., Bae Y.H., Jacobs H., Kim S.W., “Thermally on-off switching polymers for drug permeation and release”, J. Controlled Release, 11, 255 (1990)
Percot A., Lafleur M., Zhu X.X., “New hydrogels based on N-isopropylacrylamide) copolymers crosslinked with polylysine: Membrane immobilization systems”, Polymer, 41, 7231-7239 (2000)
Priest J.H., Murrey S.L., Nelson R.J., Hoffman A.S., Am. Chem. Soc. Symp. Ser., 350, 255 (1987)
Pusey P.N., Van Megan W., “Dynamic light scattering by non-ergodic media”, Physical A., 157, 705 (1989)
Qiu X., Kwan S., Wu C., “Laser light scattering study of the formation and structure of poly(N-isopropylacrylamide-co-acrylic acid) nanoparticles”, Macromolecules, 30, 6090 (1997)
Schild H.G., “Poly(N-isopropylacrylamide):experiment,theory and application”, Prog. Polym. Sci., 17, 163-249 (1992)
Snowden M.J., Morgan J., Vincent B., UK Patent, GB2262117A (1993-a)
Snowden M.J., Thomas D., Vincent B., Analyst., 118, 1367 (1993-b)
Snowden M.J., Booty M.T., in Encapsulaton and Controlled Released. Karsa D, Royal Society of Chemistry, Cambridge, 1993-c
Snowden M.J., Marston N.J., Vincent B., Colloid Polym. Sci., 272, 1273 (1994)
Wei X., Simon C., Malcolm B., “Observations on some copolymerisations involving N-isopropylacrylamide)”, Polymer, 41, 7575-7581 (2000)
Williams C., Brochard F., Frisch H.L., Annu. J. Phys. Chem., 94, 5154 (1990)
Wu W-L., Shibayama M., Roy S., Kurokawa H., Coyne L. D., Nomura S., and Stein R.S., ”Physical gels of aqueous poly(vinyl alcohol) solution:A small-angle neutron-scattering study”, Macromolecules, 23, 2245 (1990).
Wu C., Zhou S., “Thermodynamically stable globule state of a single poly(N-isopropylacrylamide) chain in water”, Macromolecules, 28, 5388 (1995-a)
Wu C., Zhou S., “Laser light scattering study of the phase transition of poly(N-isopropylacrylamide) in water”, Macromolecules, 28, 8381 (1995-b)
Yamamoto I., Iwasaki K., Hirotsu S., J. Phys. Soc. Jpn. 58, 210 (1989)
Yoo M.K., Sung Y.K., Lee Y.M., Cho C.S., “Effect of polyelectrolyte on the lower critical solution temperature of poly(N-isopropylacrylamide) in the poly(N-isopropylacrylamide-co-acrylic acid) hydrogel”, Polymer, 41, 5713-5719 (2000)
Yoshida R., Sakai K., Okano T., Sakurai Y., “²on-off² switching mechanism of pulsatile drug release using thermo-responsive poly(N-isopropylacrylamide-co-alkyl methacrylate)gels”, J. -Biomater Sci., Polymer Edn, 6, 585 (1994)
Yoshida R., Uchida K., Kaneko Y., Sakai K., Kikuchi A., Sakurai Y., Okano T., “Intelligent thermo-responsive hydrogels-mechanism of on-off switches for drug release”, Nature, 374, 240 (1995)
Zhu P.W., Napper D.H., “Light scattering studies of poly(N-isopropylacrylamide) microgel particles in mixed water-acetic acid solvent”, Macromol. Chem. Phys., 200, 1950-1955 (1999)
Zrinyi M., “Intelligent polymer gels controlled by magnetic fields”, Colloid Polym. Sci., 278, 98-103 (2000)