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Showing 1 to 20 of 28 for “"AMIC"”.
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Synthesis and Characterization of Wholly Aromatic, Water-Soluble Polyimides and Poly(amic acid)s Towards Fire Suppression Foams
… sulfonated polyimide (sPI) and poly(amic acid) (sPAA) systems for next-generation polymer-based fire suppression foams. The use of sulfonated monomers and poly(amic acid) salt formation enables tunable structures and water solubilities. The polymers maintain competitive thermal …
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Klinische und radiologische Ergebnisse nach Behandlung fokaler Knorpelschäden mittels Minced-Cartilage-Technik
… klinischen Ergebnissen nach Behandlung mittels AMIC. Die Resultate nach Minced Cartilage sind moderat und in der Untersuchung dem AMIC-Verfahren nicht überlegen.
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The preparation of high performance polymers for composites and blends: A) thermally stable ion containing polymers B) epoxy and hydroxy functional polyolefin macromers
… poly(ether-irTlides) via water soluble poly(amic acid) salt precursors. In this approach controlled molecular weight poly(amic acid)s were synthesized, and treated with stoichiometric quantities of tertiary or quaternary ammonium bases to form poly(amic acid) salts. The imidization …
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Investigation of the heating and curing rate of polymeric materials with thermal energy, continuous and pulsed microwave radiation
… constant average power. The curing rate of poly(amic acids) have also been studied with thermal energy, continuous and pulsed microwave radiation to better understand the interaction between pulsing the microwave and the polymeric material. Results from the heating rate studies indicate that the …
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Siloxane modified engineering polymers: synthesis and characteristics
… first involving the generation of soluble poly(amic acid) intermediates through reaction of various aromatic dianhydrides and aromatic diamines with a series of bis(aminopropyl)polydimethylsiloxane oligomers. These difunctional siloxane oligomers were prepared through the anionic equilibration …
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Synthesis and characterization of poly-(p-phenylene pyromellitamic acid)
<p>"Poly-(p-phenylenepyromellitamic acid)s have been synthesized over the weight average molecular weight range from 8,000 to 22,000 by reaction of pyromellitic dianhydride and p-phenylenediamine in dimethylformamide. The polymers were recovered as amorphous yellow powders having planar dimensions …
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Synthesis and characterization of high performance polyimide homopolymers and copolymers
… in a polar aprotic solvent to form a poly(amic acid). The poly(amic acid) is then cyclodehydrated by either thermal or solution imidization at high temperatures to give the fully cyclized polyimides. This research focuses on the development of a low temperature solution polymerization route …
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Synthesis and Characterization of Poly(siloxane imide) Block Copolymers and End-Functional Polyimides for Interphase Applications
End-functional poly(ether amic acid)s and poly(siloxane imide) multiblock copolymers, comprised of 2,2'-Bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA) / meta-phenylene diamine (MPDA) and hexafluoroisopropylidene-2-bis(phthalic acid anhydride) (6FDA) / meta-phenylene diamine (MPDA) …
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Characterization of Organosilicone Surfactants and Their Effects on Sulfonylurea Herbicide Activity
… oil, Rigo oil concentration, and X-77, and Dyne-Amic (a blend of an organosilicone with a crop oil concentrate), surface tension was rarely below 28 dyne/cm and spreading ability was limited on velvetleaf. In addition, the organosilicone surfactant and Kinetic also lowered dynamic surface …
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Adhesion of novel high performance polymers to carbon fibers: fiber surface treatment, characterization, and microbond single fiber pull-out test
… (SEM), single fiber tensile tests, and dynamic contact angle analysis. The commercial surface treatment which converted the AU-4 to the AS-4 fiber oxidized the carbon fiber surface. The surface of the AS-4 carbon fiber was further modified using air, oxygen, ammonia, and ethylene plasmas. …
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Structure-property behavior of polyimide homopolymers, copolymers, and blends
… imidization technique in converting the poly(amic acid) intermediate to the fully cyclized polyimide. Another important method was the incorporation of a monofunctional reagents to obtain controlled endgroups and molecular weights. Structural modifications achieved by either copolymerization …
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Synthesis and Characterization of Thermosetting Polyimide Oligomers for Microelectronics Packaging
… 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 …
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The application of siloxane modified polyimides as high performance textile coatings
… first involving the generation of soluble poly(amic acid} intermediates which were then cyclodehydrated by heating in a coamide solution, at temperatures ranging from 140 to 170°C, resulting in soluble polymer which exhibited excellent thermal and mechanical properties. Because of the different …
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Synthesis and Characterization of Wholly Aromatic Semicrystalline Polyimides Based Upon Bis(4-Aminophenoxy) Benzenes
… were synthesized via the classical two step amic acid route. More specifically, polyimides were derived from para linked 1,4-bis(4-aminophenoxy)benzene, or TPEQ (triphenyl ether diamine- hydroquinone) and its meta isomer 1,3-bis(4-aminophenoxy)benzene, or TPER (triphenyl ether …
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PEPTIDOGLYCAN REMODELLING FACTORS: KEY PLAYERS IN CELL DIVISION AND HOMEOSTASIS MAINTENANCE OF ESCHERICHIA COLI
… is mediated by PG amidases, AmiA, AmiB, and AmiC, that are activated by LytM-domain proteins both from inside the cell, with the periplasmic protein EnvC that is anchored to the divisome components FtsEX, and the outside of the cell thanks to the OM lipoproteins NlpD and ActS. In the first …
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Photocrosslinkable polyimide and poly(imide siloxane) homo- and copolymers: synthesis and characterization
… two step method of first preparing soluble poly(amic acid) prepolymers by the reaction of various aromatic dianhydrides with aromatic diamines. The siloxane modified copolymers were synthesized by reacting single or mixed components of the aromatic dianhydrides with a mixture of aromatic amine …
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Synthesis and Characterization of High Performance Polymers for Gas Separation and Water Purification Membranes and as Interfacial Agents for Thermplastic Carbon Fiber Composites
… A 100% disulfonated polyimide (sPI) and poly(amic acid) salt (PAAS) using the same monomers used for the synthesis of Ultem® were utilized as suspending agents for the fabrication of coated sub-micron polyetherimide (PEI) particles. Sub-micron particles were obtained using 1 wt% PAAS and 4 wt% …
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Periplasmic determinants of virulence in Salmonella enterica
… three proteins involved in cell septation: AmiA, AmiC, and SufI.
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The synthesis and characterization of semicrystalline polyimides
… directly synthesized via preparation of the poly(amic acid) followed by cyclodehydration by solution imidization. One requirement is the polyimide must be crystalline so that as the polyimide is formed it will crystallize and precipitate from solution as small particles in the range of 2-16 pm. …
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Kinetic and mechanistic investigations of polyimide formation and characterization of their blends with polybenzimidazoles
… by the quantitative non-aqueous titration of the amic acid functional groups as a function of reaction conditions. The homogeneous solution imidization processes were described by auto-acid catalyzed second order kinetics. The effects of heteroatom bridging groups in the diamines and dianhydrides …
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