Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 11 of 11 for “"Gel fraction"”.
-
Continuous Devulcanization of Ground Tire Rubber of Different Particle Sizes Using an Ultrasonic Twin-Screw Extruder
… curing behavior of devulcanized rubber, gel fraction and rheological properties of devulcanized and revulcanized rubbers, crosslink density and mechanical properties of revulcanized rubbers were obtained. It was found that GTR of 10 mesh devulcanized less than GTR of 30 mesh. Similarly, …
-
Statistical mechanics of the amorphous solid state of randomly crosslinked macromolecules
… but in the amorphous solid state, some fraction (called the ""gel fraction"") of the monomers become localized near random mean positions, and thermally fluctuate about these positions with random r.m.s. displacements (called ""localization lengths""). The distribution of localization …
-
Creation and modification of polymeric materials using electron beam radiation
… that the crosslinking behavior (in terms of the gel fraction produced) is strongly dependent on all three of these factors. Furthermore, the protective nature of the aromatic groups in polystyrene that is typically displayed by this polymer was not observed in this blend system.
-
Ultrasound propagation in colloidal dispersions
… Measurements of a[alpha] and c using non-gelling aqueous kaolinite suspensions are shown to agree well with theory when the eccentricity and the interactions of particles are taken into account. For gelling aqueous bentonite suspensions, a[alpha] and c were found to be time-dependent over …
-
Structure-property behavior of novel high performance thermoplastic and thermoset structural adhesives and composite matrix resins
… of these novel networks. Ninety-nine percent gel fraction networks were observed after cure at 380°C for 60 minutes. Thermomechanical properties such as tensile properties, adhesion properties, creep behavior, and heat distortion temperatures have been generated which illustrate the excellent …
-
Synthesis and Characterization of Poly(arylene ether sulfone)s for Reverse Osmosis Water Purification and Gas Separation Membranes
… produced large, ductile membranes with gel fractions approaching 99%, the highest reported for crosslinked sulfonated polysulfone oligomers. This crosslinking reaction was studied by synthesizing two series of oligomers, one based on a bisphenol A monomer and the other based on a …
-
Part I: Synthesis of Aromatic Polyketones Via Soluble Precursors Derived from Bis(A-Amininitrile)S; Part Ii: Modifications of Epoxy Resins with Functional Hyperbranched Poly(Arylene Ester)s
… CPMAS 13C NMR, kinetic FTIR spectroscopes and gel fraction analysis. Fracture toughness was improved without sacrificing thermal properties. The fracture toughness K1C values of the modified epoxies were found to be a function of the percentage loading, the molecular weights and the proportion …
-
Synthesis, crosslinking and characterization of disulfonated poly(arylene ether sulfone)s for application in reverse osmosis and proton exchange membranes
… membranes were characterized in terms of gel fraction, water uptake, swelling, self-diffusion coefficients of water, proton conductivity, methanol permeability, water permeability and salt rejection. In general, all of the crosslinked membranes had lower water uptake and swelling relative …
-
Synthesis and Characterization of Thermosetting Polyimide Oligomers for Microelectronics Packaging
… 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 …
-
Ultrasonically Aided Extrusion of Rubber Nanocomposites and Rubber Blends
… up to certain values caused an increase of the gel fraction and viscosity of compounds, minimum and maximum torques during their curing. Due to the gel formation in SBR under ultrasonic treatment, an increase of the crosslink density, modulus and tensile strength of vulcanizates was observed. In …
-
Synthesis and Characterization of Linear and Crosslinked Sulfonated Poly(arylene ether sulfone)s: Hydrocarbon-based Copolymers as Ion Conductive Membranes for Electrochemical Systems
… highly crosslinked systems with greater than 90% gel fractions. At such a high gel fraction, the water uptake of the crosslinked membranes was lower than that of the linear biphenol-based, disulfonated random copolymer with a similar IEC. Among these series of copolymers, it was shown that the …