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Katsuichiro Inoue - One of the best experts on this subject based on the ideXlab platform.
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flexural properties and impact strength of denture Base Polymer reinforced with woven glass fibers
Dental Materials, 2000Co-Authors: Takahito Kanie, K Fujii, Hiroyuki Arikawa, Katsuichiro InoueAbstract:Abstract Objectives: The present investigation was undertaken to determine the reinforcing effect of woven glass fibers on deflection, flexural strength, flexural modulus and impact strength of acrylic denture Base Polymer. Methods: Three silanized or unsilanized woven glass fibers were used. Specimens were made by heating the denture cure resin dough containing glass fibers, which were sheathed in the dough. Specimens with four different thicknesses and of five different types were made, incorporating the glass fiber. Three-point flexural test and flywheel type impact test were employed to determine the flexural properties and impact strength. Results: When specimens contained unsilanized glass fiber, the flexural strength in specimens of 1 and 2 mm thickness and the impact strength in specimens of 2 mm thickness were higher than those of specimens without glass fiber ( p On the contrary, the flexural strength and deflection in specimens reinforced with silanized glass fiber of 1 mm thickness were significantly higher ( p p ( p than that of unreinforced specimens. Statistically significant differences were found in the flexural strength ( p and in the impact strength ( p when specimens of 4 mm thickness were reinforced with two or three unsilanized glass fibers. Significance: The reinforcement with glass fiber was effective in thin specimens, and the reinforcing effect increased with the increase of the number of glass fibers in the case of thick specimens.
Andreas Ullrich - One of the best experts on this subject based on the ideXlab platform.
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synthesis of novel engineering Polymers containing basic side groups and their application in acid Base Polymer blend membranes
Separation and Purification Technology, 2001Co-Authors: Jochen Kerres, Andreas UllrichAbstract:New modified PSU Udel® containing N-basic side groups like pyridine and dimethylamino groups have been developed. The modified PSU was synthesized via (i) lithiation of PSU ortho to the sulfone bridge and (ii) reaction of the lithiated PSU with aromatic ketones like 2,2′-bipyridylketone, 4,4′-dimethylaminobenzophenone, aromatic aldehydes like 2-, 3-, and 4-pyridinealdehyde, and 4-N,N-diethylaminobenzaldehyde, and aromatic carboxylic acid esters like isonicotinic acid ethyl ester and 4-N,N-dimethylaminobenzoic acid ethyl ester. The basic PSU Polymers were characterized via NMR, elemental analysis, and thermogravimetry (TGA). Selected basic Polymers were mixed with poly(etheretherketone) (PEEK) sulfonic acid to yield Polymeric acid–Base blends. The obtained blend membranes were characterized in terms of ionic conductivity by impedance spectroscopy, in terms of morphology by transmission electron microscopy (TEM), and in terms of thermal stability by TGA. The acid–Base blends show good ionic conductivities at ion-exchange capacities of ≥1 meq/g, and good thermal stabilities. The TEM investigations yielded the result that the acid–Base-blends are miscible-no Polymer-microphase separation could be observed.
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synthesis of novel engineering Polymers containing basic side groups and their application in acid Base Polymer blend membranes
Separation and Purification Technology, 2001Co-Authors: Jochen Kerres, Andreas UllrichAbstract:New modified PSU Udel® containing N-basic side groups like pyridine and dimethylamino groups have been developed. The modified PSU was synthesized via (i) lithiation of PSU ortho to the sulfone bridge and (ii) reaction of the lithiated PSU with aromatic ketones like 2,2′-bipyridylketone, 4,4′-dimethylaminobenzophenone, aromatic aldehydes like 2-, 3-, and 4-pyridinealdehyde, and 4-N,N-diethylaminobenzaldehyde, and aromatic carboxylic acid esters like isonicotinic acid ethyl ester and 4-N,N-dimethylaminobenzoic acid ethyl ester. The basic PSU Polymers were characterized via NMR, elemental analysis, and thermogravimetry (TGA). Selected basic Polymers were mixed with poly(etheretherketone) (PEEK) sulfonic acid to yield Polymeric acid–Base blends. The obtained blend membranes were characterized in terms of ionic conductivity by impedance spectroscopy, in terms of morphology by transmission electron microscopy (TEM), and in terms of thermal stability by TGA. The acid–Base blends show good ionic conductivities at ion-exchange capacities of ≥1 meq/g, and good thermal stabilities. The TEM investigations yielded the result that the acid–Base-blends are miscible-no Polymer-microphase separation could be observed.
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synthesis and characterization of novel acid Base Polymer blends for application in membrane fuel cells
Solid State Ionics, 1999Co-Authors: Jochen Kerres, Andreas Ullrich, F Meier, Thomas HaringAbstract:Abstract In this contribution novel acid–Base Polymer blend membranes are introduced. The membranes are composed of sulfonated poly(etheretherketone) sPEEK Victrex or poly(ethersulfone) sPSU Udel® as the acidic compounds, and of PSU Udel® diaminated at the ortho position to the sulfone bridge, or poly(4-vinylpyridine), poly(benzimidazole) PBI CELAZOLE®, or poly(ethyleneimine) PEI (Aldrich) as the basic compounds. The membranes showed good proton conductivities at ion-exchange capacities IEC of 1 (IEC=meq SO 3 H/g dry membrane), and they showed excellent thermal stabilities (decomposition temperatures >270°C). Two of the membranes were tested in a H 2 membrane fuel cell and showed good performance. The specific interaction of the SO 3 H groups and of the basic N groups was investigated via FTIR for the sulfonated PSU/diaminated PSU and for the sulfonated PSU/poly(4-vinylpyridine) (Pyr) blend. It could be proved that in the dry membranes polysalt groups exist formed by the following acid–Base reaction: PSU–SO 3 H+H 2 N–PSU→[PSU–SO 3 ] − + [H 3 N–PSU], and PSU–SO 3 H+P→[PSU–SO 3 ] − + [H–Pyr].
Francesco Picchioni - One of the best experts on this subject based on the ideXlab platform.
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ionomeric membranes Based on partially sulfonated poly styrene synthesis proton conduction and methanol permeation
Journal of Membrane Science, 2000Co-Authors: N Carretta, Vincenzo Tricoli, Francesco PicchioniAbstract:Homogeneuosly sulfonated poly(styrene) (SPS) was prepared with various concentration of sulfonic acid groups in the Base Polymer. Membranes cast from these materials were investigated in relation to proton conductivity and methanol permeability in the temperature range from 20°C to 60°C. It was found that both these properties increase as the Polymer is increasingly sulfonated, with abrupt jumps occurring at a concentration of sulfonic acid groups of about 15 mol%. The most extensively sulfonated membrane exhibited conductivity equal to that of Nafion. As a consequence, this membrane material is potentially an appealing alternative to the very expensive Nafion, for a number of electrochemical applications. For the membrane with the highest degree of sulfonation we measured a methanol permeability about 70% smaller than for Nafion. This characteristic is especially desirable in applications related to the direct methanol fuel cell (DMFC).
Jochen Kerres - One of the best experts on this subject based on the ideXlab platform.
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synthesis of novel engineering Polymers containing basic side groups and their application in acid Base Polymer blend membranes
Separation and Purification Technology, 2001Co-Authors: Jochen Kerres, Andreas UllrichAbstract:New modified PSU Udel® containing N-basic side groups like pyridine and dimethylamino groups have been developed. The modified PSU was synthesized via (i) lithiation of PSU ortho to the sulfone bridge and (ii) reaction of the lithiated PSU with aromatic ketones like 2,2′-bipyridylketone, 4,4′-dimethylaminobenzophenone, aromatic aldehydes like 2-, 3-, and 4-pyridinealdehyde, and 4-N,N-diethylaminobenzaldehyde, and aromatic carboxylic acid esters like isonicotinic acid ethyl ester and 4-N,N-dimethylaminobenzoic acid ethyl ester. The basic PSU Polymers were characterized via NMR, elemental analysis, and thermogravimetry (TGA). Selected basic Polymers were mixed with poly(etheretherketone) (PEEK) sulfonic acid to yield Polymeric acid–Base blends. The obtained blend membranes were characterized in terms of ionic conductivity by impedance spectroscopy, in terms of morphology by transmission electron microscopy (TEM), and in terms of thermal stability by TGA. The acid–Base blends show good ionic conductivities at ion-exchange capacities of ≥1 meq/g, and good thermal stabilities. The TEM investigations yielded the result that the acid–Base-blends are miscible-no Polymer-microphase separation could be observed.
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synthesis of novel engineering Polymers containing basic side groups and their application in acid Base Polymer blend membranes
Separation and Purification Technology, 2001Co-Authors: Jochen Kerres, Andreas UllrichAbstract:New modified PSU Udel® containing N-basic side groups like pyridine and dimethylamino groups have been developed. The modified PSU was synthesized via (i) lithiation of PSU ortho to the sulfone bridge and (ii) reaction of the lithiated PSU with aromatic ketones like 2,2′-bipyridylketone, 4,4′-dimethylaminobenzophenone, aromatic aldehydes like 2-, 3-, and 4-pyridinealdehyde, and 4-N,N-diethylaminobenzaldehyde, and aromatic carboxylic acid esters like isonicotinic acid ethyl ester and 4-N,N-dimethylaminobenzoic acid ethyl ester. The basic PSU Polymers were characterized via NMR, elemental analysis, and thermogravimetry (TGA). Selected basic Polymers were mixed with poly(etheretherketone) (PEEK) sulfonic acid to yield Polymeric acid–Base blends. The obtained blend membranes were characterized in terms of ionic conductivity by impedance spectroscopy, in terms of morphology by transmission electron microscopy (TEM), and in terms of thermal stability by TGA. The acid–Base blends show good ionic conductivities at ion-exchange capacities of ≥1 meq/g, and good thermal stabilities. The TEM investigations yielded the result that the acid–Base-blends are miscible-no Polymer-microphase separation could be observed.
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synthesis and characterization of novel acid Base Polymer blends for application in membrane fuel cells
Solid State Ionics, 1999Co-Authors: Jochen Kerres, Andreas Ullrich, F Meier, Thomas HaringAbstract:Abstract In this contribution novel acid–Base Polymer blend membranes are introduced. The membranes are composed of sulfonated poly(etheretherketone) sPEEK Victrex or poly(ethersulfone) sPSU Udel® as the acidic compounds, and of PSU Udel® diaminated at the ortho position to the sulfone bridge, or poly(4-vinylpyridine), poly(benzimidazole) PBI CELAZOLE®, or poly(ethyleneimine) PEI (Aldrich) as the basic compounds. The membranes showed good proton conductivities at ion-exchange capacities IEC of 1 (IEC=meq SO 3 H/g dry membrane), and they showed excellent thermal stabilities (decomposition temperatures >270°C). Two of the membranes were tested in a H 2 membrane fuel cell and showed good performance. The specific interaction of the SO 3 H groups and of the basic N groups was investigated via FTIR for the sulfonated PSU/diaminated PSU and for the sulfonated PSU/poly(4-vinylpyridine) (Pyr) blend. It could be proved that in the dry membranes polysalt groups exist formed by the following acid–Base reaction: PSU–SO 3 H+H 2 N–PSU→[PSU–SO 3 ] − + [H 3 N–PSU], and PSU–SO 3 H+P→[PSU–SO 3 ] − + [H–Pyr].
Takahito Kanie - One of the best experts on this subject based on the ideXlab platform.
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flexural properties and impact strength of denture Base Polymer reinforced with woven glass fibers
Dental Materials, 2000Co-Authors: Takahito Kanie, K Fujii, Hiroyuki Arikawa, Katsuichiro InoueAbstract:Abstract Objectives: The present investigation was undertaken to determine the reinforcing effect of woven glass fibers on deflection, flexural strength, flexural modulus and impact strength of acrylic denture Base Polymer. Methods: Three silanized or unsilanized woven glass fibers were used. Specimens were made by heating the denture cure resin dough containing glass fibers, which were sheathed in the dough. Specimens with four different thicknesses and of five different types were made, incorporating the glass fiber. Three-point flexural test and flywheel type impact test were employed to determine the flexural properties and impact strength. Results: When specimens contained unsilanized glass fiber, the flexural strength in specimens of 1 and 2 mm thickness and the impact strength in specimens of 2 mm thickness were higher than those of specimens without glass fiber ( p On the contrary, the flexural strength and deflection in specimens reinforced with silanized glass fiber of 1 mm thickness were significantly higher ( p p ( p than that of unreinforced specimens. Statistically significant differences were found in the flexural strength ( p and in the impact strength ( p when specimens of 4 mm thickness were reinforced with two or three unsilanized glass fibers. Significance: The reinforcement with glass fiber was effective in thin specimens, and the reinforcing effect increased with the increase of the number of glass fibers in the case of thick specimens.