Rozprawy doktorskie: „Polyimides”

1

Qi, Yu Carleton University Dissertation Chemistry. "Synthesis and characterization of polyimides with novel structures /". Ottawa, 1997.

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2

Brink, M. Heather. "The synthesis and characterization of semicrystalline polyimides". Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-164714/.

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3

Quenneson, Marie-Eve. "Synthèse et caractérisation de films polyimides pour applications diélectriques". Lyon 1, 1986. http://www.theses.fr/1986LYO19044.

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Synthese de polybenzhydrolimides par polycondensation en solution de l'acide benzhydrol tetracarboxylique avec la methyle dianiline et l'oxydianiline; caracterisation des polymeres par gpc et diffusion de lumiere; fabrication et traitement thermique de films; trandition vitreuse par atd et analyse thermomecanique; tenue en temperature par thermogravimetrie; proprietes dielectriques

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4

Marasco, Jean-Paul. "Contribution à l'étude de nouveaux précurseurs de polyimides". Lyon 1, 1995. http://www.theses.fr/1995LYO10254.

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L'instabilite des polyamides acides en solution est engendree par l'equilibre de la reaction de polycondensation entre un dianhydride et une diamine qui peut provoquer une chute des proprietes rheologiques des solutions par hydrolyse des fonctions anhydrides terminales ou simple redistribution des masses moleculaires. Cet equilibre est supprime si l'on remplace les groupes acides par des derives esters ou amides, lesquels sont obtenus soit par modification de la structure macromoleculaire, soit par l'utilisation de monomeres actives. Deux voies de synthese relativement douces ont pu se degager pour la preparation de ces nouveaux precurseurs: l'ouverture d'un diisoimide active par une diamine ; la reaction entre un diimidazolide diamide ou diester et une diamine. La premiere voie aboutit a des chaines polyamides aromatiques contenant des fonctions paranitranilides en ortho de chaque fonction amide. Il resulte de cette structure particuliere, une competition lors de la cyclisation en polyimide qui peut provoquer une chute de la masse moleculaire mais que l'on peut orienter favorablement. La deuxieme voie permet de preparer des polyamides esters et des polyamides amides disubstitues ou le probleme de la selectivite a la cyclisation est supprime. Ce type d'approche permet en outre de mettre en uvre des precurseurs de polyimides a enchainements para a partir de monomeres enrichis. L'utilisation de tels systemes peut s'averer efficace dans la mise en uvre de polyimides rigides. Dans les deux cas les solutions obtenues sont stables et ne subissent pas la moindre variation de viscosite au cours du temps

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5

Cano, Camilo I. "Polyimide Microstructures From Powdered Precursors: Phenomenological and Parametric Studies on Particle Inflation". Akron, OH : University of Akron, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1123710711.

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Dissertation (Ph.D.)--University of Akron, Dept. of Polymer Engineering, 2005.
"August, 2005." Title from electronic dissertation title page (viewed 09/24/2005) Includes bibliographical references.

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6

Meyer, Gerald W. "Novel high performance thermosetting polyimides". Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-05222007-091420/.

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7

Dunson, Debra Lynn. "Synthesis and Characterization of Thermosetting Polyimide Oligomers for Microelectronics Packaging". Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/27394.

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A series of reactive phenylethynyl endcapped imide oligomers has been prepared in either fully cyclized or amic acid precursor form. Soluble oligomers have been synthesized with controlled molecular weights ranging from 2- to 12 Kg/mol. Molecular weight characterization was performed using SEC (size exclusion chromatography) and 13C-NMR, revealing good agreement between the theoretical and experimental (Mn) values. Crosslinked polyimides were obtained by solution or melt processing the oligomers into films and gradually heating in a programmed temperature manner up to the appropriate reaction temperature for the phenylethynyl groups, which is approximately 350-400Â°C. Thermal analysis of the resulting films showed high glass transition temperatures (>300Â°C) and excellent thermal stability, comparable to those found for thermoplastic control polyimides. The crosslinked films also had exceptional solvent resistance as evidenced by a high gel fraction (greater than or equal to 95%) following extraction in common solvents for several days. This was in contrast to the amorphous thermoplastic controls, which quickly dissolved upon immersion in solvents. The monomers used for synthesizing the polyimide oligomers were varied systematically within the series to study the influence of both molecular structure and molecular weight on the physical and film-forming properties. The incorporation of fluorinated monomers, such as 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), reduced water absorption and lowered the dielectric constant relative to non-fluorinated polyimides in the series. When flexible ether linkages were incorporated in the repeat unit by using 4,4'-oxydianiline (ODA), relatively more ductile solvent-cast films were obtained from oligomers having Mn values as low as 10 Kg/mol. Additionally, oligomer Mn and the relative rigidity/symmetry of the repeat unit structure greatly influenced the solubility of polyimides in NMP. For example, even 6FDA/p-phenylenediamine based oligomers with Mn values targeted below 10 Kg/mol precipitated from NMP at 180Â°C during solution imidization. The relationship between solution viscosities of polyimide and poly(amic acid) thermosetting oligomers and wetting/spreading ability to form continuous films during spin casting was elucidated. Employing o-dimethoxybenzene (DMB) as a cosolvent with NMP improved the film-forming ability of the fully imidized 6FDA/ODA oligomer series. This was evidenced by a decrease in viscosity (via suppression of physical-type gel formation) and better overall coverage and clarity of the films. Humidity was found to have a detrimental effect, causing the polyimide oligomers to phase separate to form cloudy or porous films. When moisture was reduced, oligomers having Mn greater than or equal to 6 Kg/mol formed spin cast films of <20 micrometer thickness with good qualitative adhesion to several inorganic substrates. Dielectric constants (epsilon) were estimated for several of the polyimides by measuring the refractive indices (n) of the films and using Maxwell's relationship (epsilon at optical frequencies is equal to n raised to the second power). The apparent dielectric constants were low, ranging from 2.47 to 2.75. The novel combination of low dielectric constant, solvent resistance and isotropic physical properties inherent in the thermosetting polyimide oligomers makes these materials excellent candidates for use as thin film insulating layers in microelectronics packaging applications.
Ph. D.

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8

Zhuang, Hong. "Synthesis and Characterization of Aryl Phosphine Oxide Containing Thermoplastic Polyimides and Thermosetting Polyimides with Controlled Reactivity". Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30692.

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Phosphorus containing monomers, bis(3-aminophenyl)methyl phosphine oxide (m-DAMPO) and bis(3-aminophenyl)phenyl phosphine oxide (m-DAPPO), were synthesized and incorporated into a thermoplastic poly(arylene ether imide) based upon 2,2'-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride and 1,3-phenylene diamine, in order to study their influence on flame resistance and other properties. DAMPO or DAPPO were quantitatively incorporated in concentrations of 25, 50, 75 and 100 mole percent, using the "one pot" ester-acid method. The number average molecular weights of the prepared materials were controlled to 20,000g/mol by off-setting the stoichiomety and endcapping with phthalic anhydride. This strategy enabled one to distinguish the effects of the phosphine oxide incoporation from the influence of molecular weight. The resulting copolymers demonstrated a significant increase in char yield as a function of the phosphine oxide content, thus suggesting improved fire resistance. Glass transition temperatures similar to the control were determined by DSC analysis. Analysis of the mechanical behavior of the DAMPO system at room temperature showed that tensile strength and elongation at failure values were comparable to the control system, while the DAPPO containing copolymers were surprisingly brittle. The influence of the reactive endgroup on the synthesis, cure behavior and network properties of thermosetting polyetherimides was investigated. Reactive phenylacetylene, acetylene and maleimide terminated poly(ether imide) oligomers were prepared and characterized. Optimal reaction conditions were established to produce fully endcapped oligomers with imidized structures and controlled molecular weight. The phenylacetylene endcapped system was synthesized by a conventional ester-acid method. The acetylene endcapped system was prepared via modified ester-acid method and the maleimide endcapped system was fabricated utilizing an amic-acid route. It was determined that phenylethynyl endcapped polymers could be thermally cured at high temperatures (350-380Â°C) providing good processibility. The networks exhibited thermal stability, chemical resistance and good adhesion strength, ideal as "primary" bonding adhesives. Acetylene and maleimide endcapped systems were prepared for application as "secondary" bonding materials, meaning that they are cured at a lower temperature than that of the Tg of the primary structure. Lap shear test results indicated good adhesion to titanium when cured at 250Â°C -280Â°C. The cured materials showed high glass transition temperatures and good thermal and thermo-oxidative stability as determined by DSC, TGA and DMA. Good chemical resistance was demonstrated via solvent extraction measurements. The influence of molecular weight between crosslinks (Mc) on thermal and mechanical behavior was also investigated. Lower molecular weight oligomers exhibited lower Tg and cure temperatures, whereas the cured networks resulting from lower molecular weight oligomers afforded higher Tg and higher gel fractions, but reduced toughness.
Ph. D.

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9

Dong, Zhenzhen. "Synthesis of two-dimensional scaffolds and metallofoldamers". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 255 p, 2008. http://proquest.umi.com/pqdweb?did=1459908101&sid=13&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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10

Billon, Laurent. "Matrices organiques à haute stabilité thermique et résistance à l'oxydation". Pau, 1996. http://www.theses.fr/1996PAUU3037.

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L'objectif de cette étude est l'amélioration de la thermostabilité dans une gamme de température supérieure à 250c, de polyimides thermodurcissables thermostables synthétisés à partir de nouveaux monomères, tout en tenant compte du procédé de mise en oeuvre. A cette fin, notre travail a consisté en l'étude de la réactivité de deux systèmes binaires en milieu méthanolique, mono ester de l'anhydride nadique ne/diamine et hexafluoro diméthyl ester HFDE/diamine. Une réactivité supérieure du composé Ne a été mise en evidence, entraînant la formation de bisnadimide Ne - diamine - Ne. L'étude structurale et thermique de ces composés montre une isomérisation endo/exo des fonctions nadimide à l'état solide ainsi qu'une grande stabilité thermique, qui nous obligent à revoir les cycles thermiques de polymérisation. La synthèse de polyimides téléchéliques nadimide, maleimide et styrenique, ainsi que leur caractérisation microstructurale, physicochimique et thermomécanique montrent la très grande complexité de ces oligomères (produits secondaires, polymolécularité, isomérisation endo/exo des fonctions nadimide, transition vitreuse et sous vitreuse). Les résultats obtenus ont été discutés dans le cadre des relations structure/propriétés des polyimides téléchéliques. L'étude des prépolymères fonctionnalises nadimide a montré l'influence de l'isomérisation endo/exo sur la transition vitreuse. Ces résultats jouent un rôle important lors de la réticulation de ces systèmes car la temperature finale du cycle de polymérisation depend de la valeur de la température de transition vitreuse.

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11

Rogers, Martin E. "Synthesis and characterization of high performance polyimide homopolymers and copolymers". Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10022007-144559/.

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12

Ngo, Thomas T. "Chemistry and characterization of cycloaddition polyimides". Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/27107.

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13

Dangarwala, Gaurav A. "A model of the change in viscosity of polyimide PMR-15 during cure". Ohio : Ohio University, 1993. http://www.ohiolink.edu/etd/view.cgi?ohiou1175284832.

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14

Chin, Joannie W. "Surface characterization and adhesion of plasma-modified polyimides". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040355/.

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15

Sejour, Hensley. "Investigation of Dithiolenes for Propylene/Propane Membrane Separations". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19697.

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Polyimide membranes containing nickel dithiolenes were investigated for the separation of propylene and propane. Permeation and sorption experiments were conducted as well thermal property analyses. Results indicate that the dithiolene has an antiplasticizing effect on the polymers studied. Upon addition of the dithiolene there is a subsequent reduction in the permeability coefficient and the permeability selectivity remains relatively unchanged. There is some evidence of increases in solubility selectivity, but a larger decrease in diffusivity selectivity results in a decrease in the permeability selectivity. Investigation of the thermal and mechanical properties of dithiolene-containing films indicates a reduction in fractional free volume as well as the glass transition temperature when compared to the pure polymer. There is also an increase in the modulus of the films upon addition of the dithiolene. The implications of these results and their correlation with antiplasticization are discussed.

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16

Gopalanarayanan, Bhaskar. "Analysis of Thermoplastic Polyimide + Polymer Liquid Crystal Blends". Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc279285/.

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Thermoplastic polyimides (TPIs) exhibit high glass transition temperatures (Tgs), which make them useful in high performance applications. Amorphous and semicrystalline TPIs show sub-Tg relaxations, which can aid in improving strength characteristics through energy absorption. The a relaxation of both types of TPIs indicates a cooperative nature. The semicrystalline TPI shows thermo-irreversible cold crystallization phenomenon. The polymer liquid crystal (PLC) used in the blends is thermotropic and with longitudinal molecular structure. The small heat capacity change (ACP) associated with the glass transition indicates the PLC to be rigid rod in nature. The PLC shows a small endotherm associated with the melting. The addition of PLC to the semicrystalline TPI does not significantly affect the Tg or the melting point (Tm). The cold crystallization temperature (Tc) increases with the addition of the PLC, indicating channeling phenomenon. The addition of PLC also causes a negative deviation of the ACP, which is another evidence for channeling. The TPI, PLC and their blends show high thermal stability. The semicrystalline TPI absorbs moisture; this effect decreases with the addition of the PLC. The absorbed moisture does not show any effect on the degradation. The addition of PLC beyond 30 wt.% does not result in an improvement of properties. The amorphous TPI + PLC blends also show the negative deviation of ACP from linearity with composition. The addition of PLC causes a decrease in the thermal conductivity in the transverse direction to the PLC orientation. The thermomechanical analysis indicates isotropic expansivity for the amorphous TPI and a small anisotropy for the semicrystalline TPI. The PLC shows large anisotropy in expansivity. Even 5 wt. % concentration of PLC in the blend induces considerable anisotropy in the expansivity. Thus, blends show controllable expansivity through PLC concentration. Amorphous TPI + PLC blends also show excellent film formability. The amorphous TPI blends show good potential for applications requiring high thermal stability, controlled expansivity and good film formability.

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17

He, Zhanqi. "A cycloaddition approach to the curing of polyimides". Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/27301.

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18

Dawood, Bann. "Mixed matrix membranes consisting of porous polyimide networks and polymers of intrinsic microporosity for gas separation". Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/mixed-matrix-membranes-consisting-of-porous-polyimide-networks-and-polymers-of-intrinsic-microporosity-for-gas-separation(bb07d633-69dc-471b-a5ae-f1f0888615b6).html.

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This research aimed to develop the fabrication of mixed matrix membranes (MMMs) utilizing a polymer of intrinsic microporosity (PIM-1) with porous polyimide networks, and to explore their effect on gas transport properties. PIM-1 has been chosen as polymer matrix for its high surface area and high sorption of gases. It is also considered as interesting candidate for membrane gas separation. PIM-1 has been synthesized successfully using high temperature methods (40 min, 160 oC) and low temperature methods (72 h, 65 oC). Porous polyimide networks have been chosen as organic fillers as they have good chemical affinity to polymer matrix and can adhere much better than inorganic fillers. MPN-1 and MPN-2 were synthesized by condensation polymerization of A2 (dianhydride) and B4 (tetraamino). The polymer matrix (PIM-1) and network polyimide fillers were characterized using various characterization techniques, including FTIR, NMR spectroscopy, TGA and N2 sorption analysis. MMMs were fabricated successfully utilizing PIM-1 with 10, 20, and 30wt. % loadings of fillers. The MMMs prepared were homogenous on a macroscale. They characterized using different techniques, such as FTIR spectroscopy, powder x-ray diffraction, and scanning electron microscopy. The gas transport properties of MMMs were obtained using a time lag method. The treatment of MMMs with alcohol showed an increase in the permeability and diffusivity of gases. We aimed in this research to increase solubility of microporous polyimide network (MPN-1) by decreasing the extent of network structure. Different strategies have been utilized. First, using different molar ratios and second, using end-capping modification. The polymers were characterized using various techniques, including FTIR, NMR spectroscopy and TGA. Following this, their CO2 uptake and solubility are also examined.

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19

Tschen, Molina Francisco. "Synthesis of novel polyimides for the testing of structure-processing and property relations when used to form high temperature polymer matrices". Texas A&M University, 2005. http://hdl.handle.net/1969.1/5006.

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High-performance polymers have found an extreme range of applications in the aerospace industry. Composites which have polymers incorporated in them can usually meet the needs of the design, and are the ideal materials for aerospace applications due to their light weight, high strength, and radar transparency. Phenyl-ethynyl terminated oligomers, for example, have found many uses in the aerospace industry. Phenyl-ethynyl terminated oligomers (AFR-PEPA-N) exhibit glass-transition temperatures of up to 450ÃÂ°C. Unfortunately crystals form due to interactions of the oligomers. These crystals do not melt until 360ÃÂ°C after 15 minutes when the resin is already 50% cured. Investigation was performed to find any possible alteration to the end-caps and monomer chain elements of the current AFR-PEPA-N. Several siloxane related amines were added to the AFR-PEPA-N chain to form protective coatings when in service at high temperatures. The new poly(siloxane imide) showed an increase in processability while mantaining AFR-PEPA-N properties. In addition, phenyl-ethnyl end-caps were substituted with an ethynyl end-caps which showed no improvement in processability.

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20

Hardaker, Stephen S. "Application of molecular modeling for the determination of intrinsic molecular parameters and characterization of orientation in PMDA-ODA polyimide". Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/8536.

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21

Dorsey, Kyra. "Formation, morphology, and properties of oriented LaRC-IA filaments". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/10948.

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22

Frazier, Albert Bruno. "The use of polyimide for the development of micromachined materials, processes and devices". Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/15696.

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23

Droge, Stefan. "Analysis of hairy-rod polyimides for photoalignment". Thesis, University of Hull, 2008. http://hydra.hull.ac.uk/resources/hull:1604.

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The evaluation of novel polyimides for nematic liquid crystal alignment by UV irradiation was the aim of this thesis. Homeotropic liquid crystal (LC) alignment was observed for the majority of the in-house synthesised hairy-rod polyimides (PIs). Oblique unpolarised UV irradiation of branched PIs results in pretilted LCs of 2 deg to 88 deg depending on chemical composition, processing history and fluence. The initial pretilted alignment collapsed to homogeneous alignment at higher fluences, which was dependent on the main chain, side chain combination. Minimal changes in the UV/VIS and FTIR absorption spectra were found for fluences at which pretilted LC alignment occurred. For higher fluences photodegradation could be observed in the FTIR spectra. AFM measurements revealed an increased surface roughness after UV irradiation, but no surface anisotropy could be observed. X-ray reflectivity measurements showed film shrinkage after in-situ UV irradiation with identical trends as was observed for the collapse of the LC pretilt. Modeling revealed an increased electron density at the surface and a less diffuse interface following UV exposure. Bragg features in the reflectivity curve suggested a periodical internal film morphology, which was confirmed by grazing incidence X-ray diffraction (GIXRD). Models of chain orientations are proposed for three PIs and the UV induced morphology change analysed. GIXRD probes the surface or bulk of the thin film and an anisotropic increase in order was found for the in-plane surface scan at low fluences, followed by a general order decrease for higher fluences. The LC tilts in the direction of UV irradiation and not toward higher order. An entropy-related photodegradation model is suggested whereby the LC tilts toward maximum surface disorder to minimise free energy. Polarised UV irradiation of main chain only PIs results in homogeneous LC alignment. This was used to photoalign a LC semiconductor material, resulting in a polarised UV absorption ratio of 11 to 1.

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24

Wickman, Kristy. "The Synthesis of Polyimides Containing Oxyalkylene Units". Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1405623715.

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25

Razdan, Mayuri. "Adhesion of copper to photo-oxidized polyimides /". Online version of thesis, 2008. http://hdl.handle.net/1850/7909.

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26

Arnold, Cynthia A. "Structure-property behavior of polyimide homopolymers, copolymers, and blends". Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115012/.

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27

Moy, Thomas M. "Synthesis and characterization of soluble, high temperature aromatic polyimides". Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10022007-144551/.

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28

Karangu, Njeri T. "Synthesis, characterization and properties of diacetylene functionalized polyimides". Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/27368.

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29

Wilkens, Diana L. "Synthesis of poly(arylene ether sulfone)-polyimide segmented copolymers". Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41592.

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Poly(arylene ether sulfone) oligomers have been synthesized by nucleophilic aromatic substitution using potassium carbonate as base and N-methyl pyrrolidinone (NMP) as solvent. m-Aminophenol was used as an endcapper to control the molecular weight of the oligomers and to provide functional amine termination. These amine terminated oligomers can then be utilized in a variety of post reactions. Poly(arylene ether sulfone)-Polyimide segmented copolymers were synthesized using a solution imidization procedure with NMP as the solvent and o-dichlorobenzene as the azeotroping agent. The polysulfone oligomers were reacted into the system via the diamine oligomer. The segmented copolymers demonstrated good solubility characteristics, high thermal stability, and high glass transition temperatures. Previously, polyimides containing pyromellitic dianhydride (PMDA) did not remain soluble in the NMP solvent during the solution imidization, but rather precipitated out of solution when partially imidized. Incorporation of the amine terminated polysulfone oligomers into PMDA containing copolymers resulted in Systems that remained soluble even after completion of imidization. The resulting copolymers were completely soluble in many of the high boiling solvents. The copolymers demonstrated high thermal Stability and high glass transition temperatures.
Master of Science

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30

Sim, Seok-Hoon. "Modifications of polyimides and polyimide-inorganic oxide hybrids with perfluoroether oligomers for use as matrices for carbon-fibre composites". Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/35624.

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The performance of a polyimide derived from a low molecular weight polyamic acid (Skybond 703) and the corresponding polyimide-silica hybrids, used as matrices for Carbon-fibre composites, was evaluated. The study involved the incorporation of telechelically modified perfluoroether oligomers into the resin systems. Telechelic modifications of the hydroxyl-terminated perfluoroether oligomer were carried out in order to achieve the required compatibility with the polyimide phase through grafting reactions with the polyamic acid precursor. In the case of hybrids, the compatibility requirements were extended also to the prehydrolysed alkoxysilane solution added to the polyamic acid mixtures. The latter was achieved with the incorporation of a silane coupling agent (γ-glycidyloxypropyltrimethoxysilane), which resulted in the formation of nano-scale silica domains in the polyimide.

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31

Kulkarni, Pallavi P. "Effect of polyhedral oligomeric silsesquioxane on gas transport properties of polyimide /". Connect to full text in OhioLINK ETD Center, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1196883179.

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Dissertation (Ph.D.)--University of Toledo, 2007.
Typescript. "Submitted as partial fulfillment of the requirements for the Doctor of Philosophy degree in the Engineering Science Concentration in Chemical and Environmental Engineering." Bibliography: leaves 213-221.

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32

Chen, Xin. "High temperature performance of glass fabric/polyimide composites". Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/11165.

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33

Criss, Jim McRae. "Synthesis, characterization, and study of polyimide processing additives and their effect on polyimide properties". Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/20015.

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34

Lee, Jae-kyun. "Structure-property correlation of polyimide thin films and line structures /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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35

Marin, Nicolas. "Contribution à l'étude de la diffusion d'impuretés métalliques dans un film polymère (Kapton) sous et hors irradiation /". Gif-sur-Yvette : Direction de l'information scientifique et technique, CEA Saclay, 1996. http://catalogue.bnf.fr/ark:/12148/cb358261299.

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36

Schmitt, Agnès. "Étude de l'adhésion d'une colle cyanoacrylate sur un polyimide kapton et un composite époxyde chargé fibres de verre". ENSMP, 2000. http://www.theses.fr/2000ENMP0963.

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Ce travail s'inscrit dans l’étude des interfaces colle cyanoacrylate / polyimide kapton et colle cyanoacrylate / composite verre-époxyde. Une préparation de surface par nettoyage, permettant d’améliorer l’adhérence de l'interface, est considérée. Les matériaux constituant les assemblages sont étudiés avant collage, en terme de morphologie et de physico-chimie. La polymérisation de la colle a été étudiée par différentes méthodes, permettant d'appréhender sa cinétique et sa phase d'inhibition. Les films polyimides et composites sont analysés avant et après passage dans un procédé de mise en œuvre industriel. L'étude morphologique montre la présence d'agents glissants sur le polyimide et celle de cratères et de remontées de fibres sur le composite. Après mise en œuvre, la morphologie n'est pas modifiée mais une couche de contamination par du pdms (poly(dimethylsiloxane)) est détectée à l'extrême surface. Après nettoyage des films, la morphologie n’évolue pas, alors que l'agent perturbateur disparaît des surfaces, des composes hydrocarbones sont éliminés, l'alcool est adsorbé et des réactions secondaires se produisent. L'adhérence est traitée en utilisant des essais interprétés par la mécanique de la rupture, comme un essai d'arrachement par indentation, proche du test cerache, en mode monotone et en mode fatigue. En mode monotone, la raideur des assemblages est obtenue. L'effet de la vitesse sur la contrainte à la rupture et sur les faciès de rupture (stick-slip) est mis en évidence. La corrélation adhésion-adhérence est finalement réalisée grâce à l'étude de la compatibilité des matériaux, notamment avec les paramètres de solubilité. Une étude expérimentale des liaisons créées à l'interface permet de montrer l'existence de liaisons hydrogène entre l'ester de la colle et le substrat. Les liaisons alcools classiquement mises en avant dans la littérature ne sont pas observées expérimentalement
Few adhesion studies on cyanoacrylate glue exist despite its large use. This study deals with cyanoacrylate glue / Kapton polyimide and cyanoacrylate glue / glass-epoxyde composite interfaces. A surface treatment (cleaning) for adhesion improvment is considered. Materials morphology and chemical structure are studied before assembly. A study of the glue leads to polymerization kinetic measurement and shows characteristic inhibition phase. Polyimide and composite films are studied before and after industrial processing. A morphological study shows the presence of slipping particules on polyimide, craters and rising fibres on composite. After processing, no change appears in the film morphology, but a PDMS (poly(dimethylsiloxane)) contamination layer is detected on extreme surface. After films cleaning, the morphology doesn't change, whereas surface contamination is eliminated, hydrocarbon compounds disappear, alcohol is adorbed and secondary reactions occur. The mechanical adhesion study deals with fracture mechanics test. A pull ou test, based on indentation test and Cerache test, is used in monotonous and fatigue modes. In monotonous mode, assemblies stiffness is obtained. The cracking speed effect on rupture strain and on rupture locus is shown (stick-slip). Adhesion-mechanical adhesion correlation is finally realized thanks to materials compatibility with the use of solubility parameters. An experimental study of bonds created at interface lead to hydrogen bonds between ester from the glue and the substrate. The literature refers generally to alcohol bonds, but those are not observed

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37

Qi, Yu. "Synthesis and characterization of polyimides with novel structures". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22174.pdf.

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38

Ghassemi, Hossein. "Synthesis and properties of novel polyimides utilizing hydrazine". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28451.

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Hydrazine reacts with phthalic anhydride to give a mixture of cyclic hydrazide and N-aminophthalimide. However, the N-aminoimide is exclusively formed in high yield by the reaction of 1,8-naphthalic anhydride with hydrazine. N-aminoimides act as amines and react further with cyclic anhydrides to yield stable bisimides containing an N-N linkage. The syntheses of several bis(N-aminoimide)s from the corresponding bisanhydrides which contain the naphthalic anhydride moiety have been described. Novel high molecular weight polyimides have been synthesized by the reaction of these bis(N-aminoimide)s with cyclic dianhydrides. Most of the polymers are amorphous and are soluble in solvents such as chloroform, o-dichlorobenzene, N-methylpyrrolidinone and m-cresol. Only those polyimides having less flexible groups in their structure or containing a significant amount of perylene units show some degree of crystallinity.
All of the polymers show remarkably high glass transition temperatures, as high as 455$ sp circ$C. Their 5% weight loss by thermogravimetric analysis in an atmosphere of air or nitrogen are all above 440$ sp circ$C. Most of these polymers are highly fluorescent. Their emission spectra are in the visible region and show some evidence for an excited energy transfer and molecular aggregation.

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39

Bird, Matthew B. "Modification of Polyimides by Non-Covalent Cross-Linking". Thesis, University of Reading, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507009.

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Shah, Saral. "SOLUTION PROCESSIBLE AROMATIC POLYIMIDES VIA DIELS ALDER PRECURSOR". Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3509.

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Aromatic polyimides are interesting materials since they possess outstanding key properties such as thermoxidative stability, high mechanical strength, high modulus, excellent electrical properties, and superior chemical resistance. However, their low solubility makes them difficult to characterize, process and obtain high molecular weight polymer. In this report, we synthesized a series of precursor polymers that contains Diels-Alder (DA) adducts of anthracene. Different dienophiles were tried. These precursor polymers are soluble in common organic solvents such as chloroform and can be easily processed to thin films. Heating the film above 215 degree induce retro-DA reaction, which generated the fully aromatic polyimides in situ. The solid-state retro-DA reactions were monitored by ATR-FTIR and UV-Vis spectra. The fully aromatic polyimides are highly stable and their thin films are insoluble in organic solvents. Profilometry and AFM studies showed that after the thermal treatment, the films are smooth and pin-hole free, while the volumes decreased with a percentage close to the weight loss caused by retro-DA reaction. These Polymers can have a wide range of potential applications from thermal patterning polymers to organic photovoltaics.
M.S.
Department of Chemistry
Sciences
Industrial Chemistry MS

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41

Georgiades, Alexis N. "Synthesis and characterisation of novel high temperature polyimides". Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/733/.

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Bernard, Robert John. "The synthesis and characterisation of sulfonate-containing polyimides". Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248285.

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Rancourt, James David. "Electrical properties of polyimides modified with metal salts". Diss., Virginia Tech, 1987. http://hdl.handle.net/10919/39288.

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Oraison, Jean-Marc. "Synthèse et caractérisation de films diélectriques polyimides cardo". Lyon 1, 1991. http://www.theses.fr/1991LYO10114.

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La necessite de disposer de materiaux thermostables solubles pour leur utilisation comme couches d'isolation intermetalliques ou comme elements d'interconnexion nous a conduit a developper des polymeres a structure de chaines rigides associee a une faible polarite. Nous avons synthetise trois polyimides cardo par polycondensation dans la nmp d'une diamine primaire la dapf avec differents dianhydrides: le btda, le 6fda ou encore un melange de ce dernier avec le pmda. Nous obtenons ainsi des polyimides totalement cyclises qui peuvent etre separes par precipitation dans l'eau. Les tests de solubilite ont revele que les solvants de ces polyimides doivent presenter une d elevee et un #h et un #p faibles. Lors de la mise en uvre de films par voie solvant des contraintes sont creees suite au processus d'evaporation du solvant et a la difference de dilatation thermique entre le film et le substrat. Des analyses thermomecaniques et de refractometrie nous ont permis de caracteriser ces phenomenes. Par ailleurs, ces materiaux presentent une tres bonne stabilite thermique (temperature de degradation >350c) et des transitions vitreuses elevees > a 340c et l'evolution des constantes dielectriques est en accord avec la structure chimique des chaines. Les absorptions dielectriques observees sur les spectres isofrequences ont ete attribuees a basse temperature (t<75c) a la presence d'eau puis a haute temperature aux rotules flexibles liant les groupements imides et enfin a des phenomenes de conduction

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Wang, Lei. "Synthesis and Characterization of Polyimides with Twisted Configurations". University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1133362562.

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LEVINE, KIRILL LVOVICH. "SYNTHESIS, CHARACTERIZATION AND PROPERTIES OF POLYPYRROLE/POLYIMIDES COMPOSITES". University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1038338668.

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47

Kull, Kenneth. "Synthesis and Characterization of Novel Polyurethanes and Polyimides". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6530.

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Four novel high performance soft thermoplastic polyurethane elastomers utilizing methylene bis(4-cyclohexylisocyanate) as a hard segment, 1,4 butanediol as a chain extender and modified low crystallinity carbonate copolymer as a soft segment were synthesized. The samples were characterized by infrared spectroscopy (FTIR), tensile, elongation, hardness, abrasion resistance and atomic force microscopy (AFM). SAXS data shows evidence of an interdomain "center-to-center" distance of 45Å. DSC traces show evidence of one glass transition temperature and a weak melting region. DMA analysis reveals a low temperature secondary relaxation and the glass to rubber transition followed by a rubbery plateau. All samples demonstrated the ability to maintain excellent physical and mechanical properties in hardness below 70 Shore A. Thermoplastic polyurethanes in this study do not possess surface tackiness usually observed in soft polyurethanes. Biocompatability testing showed no toxicity of these samples as indicated by USP Class VI, MEM Elution Cytotoxicity and Hemolysis toxicology reports. This novel type of polyurethane material targets growing markets of biocompatible polymers and can be utilized as peristaltic pump tubing, balloon catheters, enteral feeding tubes and medical equipment gaskets and seals. Polyimides are a family of engineering polymers with temperature stability, high polarity and solvent resistance. These high-performance materials are used in aerospace applications, in the production of semi-dry battery binders, and in a host of other high temperature demanding situations. However, their glass transition and melt temperatures are characteristically very high and close to one another, making them difficult to melt process and limiting them to thin film formulations from their polyamic acid precursors. Here, a new series of thermoplastic polyether-polyimides (PE-PIs) are synthesized by incorporating a polyetherdiamine monomer to reduce rigidity and break up an otherwise fully aromatic backbone as seen with most conventional polyimides. It will be shown that control of the stoichiometric ratio between the aromatic 4,4'-methylenebis(2,6-dimethylaniline) and aliphatic polyetherdiamines relative to PMDA (pyromellitic dianhydride), along with the molecular weight of the polyetheramine, can be used to tune the Tg to best balance between temperature performance and processability.

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Romeo, Michael Joseph. "Design, synthesis, and characterization of novel, low dielectric, photodefinable polymers". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24782.

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Thesis (Ph.D.)--Chemical Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Henderson, Cliff; Committee Member: Beckham, Haskell; Committee Member: Hess, Dennis; Committee Member: Koros, William; Committee Member: Tolbert, Laren.

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Mokthari, Ilham. "Synthèse et caractérisation de polyimides poreux à faible constante diélectrique". Chambéry, 2005. http://www.theses.fr/2005CHAMS049.

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Le travail proposé concerne la réalisation de matériaux à faible constante diélectrique pour une application en microélectronique. L'objectif consiste à réaliser des matériaux possédant non seulement de faibles valeurs de permittivité, mais également une bonne stabilité thermique et une haute température de transition vitreuse. La stratégie adoptée repose sur la création de porosité par dégradation thermique de séquences macromoléculaires thermolabiles (polycaprolactone) dispersées ou liées de façon covalente dans une matrice thermostable (polyimide), légèrement réticulée par un traitement photochimique. La première partie de ce mémoire a été consacrée à la synthèse et à la caractérisation de matrices polyimides. Dans une seconde partie, des segments polycaprolactones fonctionalisés (amine-PCL ou diamine-PCL) ont été synthétisés, caractérisés, puis utilisés comme macromonomères en polycondensation, afin d'obtenir des copolymères à architectures variées (triblocs ou peignes). La dernière partie est consacrée à l'élaboration de matériaux poreux. Dans un premier temps, au travers de diverses caractérisations thermiques de la PCL libre, dispersée ou greffée, les conditions expérimentales permettant de dégrader totalement les segments macromoléculaires thermolabiles sans pour autant affecter la matrice polyimide ont été identifiées. Dans un deuxième temps, une étude précise de l'influence des différents paramètres (nature de la matrice PI, Tg, taux de PCL introduit, PCL greffée ou dispersée dans la matrice PI, degré de comptabilité entre les chaînes PCL et les chaînes PI, nature du traitement thermique destiné à éliminer les segments PCL. . . ) sur l'obtention de polymères poreux a été réalisée. Les résultats obtenus suggèrent que deux paramètres sont indispensables à l'obtention de matériaux poreux : d'une part, une température de transition vitreuse de la matrice élevée et d'autre part, une ségrégation de phase des segments thermolabiles dans la matrice thermostable
This research work concerns the elaboration of low dielectric constant materials to be used as interlayer dielectrics in microelectronics. The strategy adopted for the generation of porosity relies on the thermal degradation of thermolabiles polycaprolactone sequences simply dispersed or covalently linked to thermostable polyimide matrices, slightly crosslinked by a photochemical process. The first part of this work is devoted to the synthesis and characterization of different polyimides matrices. In a second part, functionnalized polycaprolactone segments (amine-PCL or diamine-PCL) have been synthesized, characterized and involved in a polycondensation reaction in order to end up with controlled architecture copolymers. The last part of the work is related to the elaboration of porous materials. First, the experimental conditions suitable for a complete elimination of the thermolabile segments without any mage to the polyimide matrix have been determined. Therefore, a precise study of the influence of different parameters (polyimide structure, glass transition temperature, polycaprolactone proportion introduced. . . ) on the elaboration of porous structures have been realized. The results obtained suggest at two parameters are crucial for the elaboration of porosity : a high transition temperature of the matrix as well as a phase separation of the thermolabile segments in the themostable polymer

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Salvetat, Jean-Paul. "Transition isolant-conducteur dans le polyimide Kapton irradié par des ions lourds rapides". Lyon 1, 1995. http://www.theses.fr/1995LYO19003.

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Des films minces de polyimide kapton-h ont ete irradies, sous vide, par des ions lourds rapides en regime d'excitations electroniques. Des mesures de conductivite continue et alternative, et de resonance paramagnetique electronique en mode continu, ont mis en evidence une transition isolant-conducteur, se deroulant en quatre etapes. Dans un premier temps, a faible fluence, l'endommagement est concentre dans les traces latentes des ions. Un grand nombre de defauts paramagnetiques est cree. La trace est un milieu moleculaire desordonne, ou la diffusion des spins et des charges reste tres localisee. Son volume est approximativement proportionnel au carre du pouvoir d'arret electronique. Dans la deuxieme etape, un semi-conducteur covalent amorphe, dope par des defauts d'irradiation, est progressivement cree par recouvrement des traces. La conductivite est ohmique a champ faible, suit une loi d'arrhenius en fonction de la temperature, et la dependance en champ fort est de type poole-frenkel. Des amas carbones conjugues se forment egalement sous irradiation dans la matrice degradee. A partir d'une concentration critique, la conduction s'effectue par saut entre les amas conjugues. Les interactions coulombiennes entre les electrons jouent alors un role determinant dans le processus de conduction. Lorsque les liaisons conjuguees s'etendent a l'ensemble du solide, on obtient un bon conducteur desordonne, dont les caracteristiques sont proches d'un polyacetylene fortement dope ou d'un carbone vitreux. L'hypothese de la formation d'un graphite polycristallin est ici exclue. Comme dans de nombreux systemes carbones, riches en liaisons conjuguees, l'oxygene de l'air a un effet important sur la conductivite et le paramagnetisme. On observe notamment une diminution de la densite de spins, et de la conductivite, sous air ou sous oxygene. Cet effet, rarement evoque dans les precedents travaux d'irradiation, est utilise ici comme sonde de la dynamique de spin et de charges

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