Poly(N-isopropylacrylamide) (PNIPAM) is a smart polymer exhibiting an inverse temperature-solubility relationship with a sharp transition at 32&deg / C in its aqueous solution. Due to its reversible thermo-responsive phase transition behavior at around body temperature, PNIPAM promise a potential for a variety of novel applications especially in biotechnology and medicine. PNIPAM can be produced by conventional polymerization methods, as well as by use of ionizing radiation, primarily by gamma which leads mainly to a residual-free crosslinked polymer. In this study, RF plasma (glow discharge) technique is used as a novel synthesis method in solid state leading to higher proportions of linear polymer. Since plasma method is an additive-/initiator-free process, a residual-free polymer is expected. To obtain a better understanding of the plasma induced solid state polymerization mechanism of NIPAM, X-ray data are used. It is found that crystalline structures of Acrylamide (AAm) and NIPAM are isomorphous. Plasma and post plasma aging effects on crystalline structure of NIPAM are followed. From the Electron Paramagnetic Resonance (EPR) investigations it is observed that post plasma polymerization of NIPAM in solid state proceed by radicalic mechanism. After determination of temperature range in which the radical formed by plasma treatment of NIPAM is highly stable, decay kinetics of the propagating radical in solid state after plasma treatment has been studied in detail.

In this study, N-vinylcaprolactam was polymerized by radiation in the solid state. The polymerization was carried out at room temperayure under vacuum and open to atmosphere respectively. The polymerization mechanism showed autoacceleration and the rate of polymerization was higher in the presence of oxygen. However the limiting conversion was 100% under vacuum conditions and 90% in the present of oxygen. This is due to the low molecular weight olgomer formation in the presence of oxygen. The polymers were characterized by FT-IR, NMR, DSC, TGA, Light Scattering, GPC, Viscosity, X_Ray and mass spectrometry methods. FT-IR and NMR results showed that polymerization proceded through the vinyl groups and caprolactam is a pendent group. DSC results show that the polymer produced could be polymerized further or crosslink by heat treatment. The Tg value for the polymerobtained from radiation induced polymerization was about 147 C. It increased to 174 C after thermal treatment. Solution properties were studied by Light Scattering, GPC and viscosity measurements. The solutionbehavioor of the polymer was highyl dependent on the molecular weight of the polymer. This effect was also the conformation of polymer in solution and the viscosity properties. Since the polymer obtained had low molecular weight a regular relation could not be obtained for the radius of gyration, hydrodynamic radius and viscosity. X-ray diffraction studies showed that the monomer structure was retained up to about 86% conversion of monomer to polymer. The chain structure of the polymer was confirmed further by mass spectroscopic results.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第24585号 / 工博第5091号 / 新制||工||1975(附属図書館) / 京都大学大学院工学研究科分子工学専攻 / (主査)教授 関 修平, 教授 梶 弘典, 教授 SIVANIAH Easan / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

ABSTRACT SYNTHESIS AND CHARACTERIZATION OF POLY(DIHALOPHENYLENE OXIDE)S AND ITS DERIVATIVES FROM DIAMMINE BIS(TRIHALOPHENOLATO) Cu(II) COMPLEXES Sonsuz, Muammer M.S., Department of Chemistry Supervisor: Assoc. Prof. Dr. G&uuml / ls&uuml / n G&ouml / kaga&ccedil / Co-Supervisor: Prof. Dr. Duygu Kisak&uuml / rek September 2004, 62 pages In this study, synthesis and characterization of poly(dihalophenylene oxide)s were done by thermal decomposition of diamminebis(trichlorophenolato) copper(II) and diamminebis(tribromophenolato) Cu(II) complexes in solid state. 2,4,6-trichlorophenol (TCP), 2,4,6-tribromophenol (TBP) and ammonia were used as ligands in the complex syntheses. The complexes were characterized by means of X-ray diffraction, FTIR, DSC, mass spectroscopy, magnetic susceptibility and C, H, N elemental analyses. Synthesized complexes were decomposed thermally in solid state for the production of poly(dihalophenylene oxide)s. Polymerizations were carried out at two different conditions. In the first condition, the decomposition time was kept constant at 3 hours and temperature was varied for each sample to observe the effect of temperature on decomposition. In the second condition, the decomposition temperature was kept constant at maximum conversion temperature and the period of time was varied from 3 hours to 48 hours in order to define the effect of time on the decomposition. Synthesized polymers were characterized by FTIR, 1H-NMR, 13C-NMR, DSC, SEM, FAAS and viscometric measurements. At the end of the study, it was observed that, the percent conversion and the structure of the polymeric product depend on polymerization condition and the type of the starting complex.

Acetylenedicarboxylic acid monopotassium salt, ADCA-K, was polymerized by radiation induced solid-state and chemical initiator induced solution polymerization methods. Radiation induced solid-state polymerization was carried out by Co-60 g-radiation at room temperature. The powder polymer obtained was soluble in water but insoluble in common organic solvents. The solution polymerization initiated by benzoylperoxide was carried out in an oil bath at 90&deg / C. The polymer obtained was soluble in water but insoluble in dimethylsulfoxide. In the first stage of the polymerization, H2O, CO and/or CO2 gases were evolved and the polymerization was proceeded on the acetylene group. The polymers obtained were characterized by FT-IR, DSC, TGA-FTIR, NMR and DP-MS methods. The crystal structure effect on polymerization was investigated by X-Ray method. The monomer is monoclinic with a space group of C2/c. The unit cell parameters are a=795.4, b=1192.6, c=591.8 pm and b=105.40. Polymer showed a partial polycrystalline structure. The larger fraction of polymer has identical crystal structure to that of the monomer. Therefore, polymerization takes place a topotactic mechanism.

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