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New organic-inorganic hybrid materials and their anti-electrostatic hybrid membranes are prepared via sol-gel process. The polycondensation of epoxy oligomers and AEAPS/Al2O3 complexes which are organically surface modified submicrometer aluminum trihydroxide inorganic fillers with an active aminoterminal silane coupling agent, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS), are performed. AEAPS enhances the interfacial interactions between the inorganic fillers and epoxy polymers. Meanwhile, this coupling agent maintains well dispersion of fillers in these composites. To improve the mechanical strength and thermal stability, pyromellitic dianhydride (PMDA) is used as curing agent. These hybrid films prepared from this method have excellent physical properties, such as UV-shielding, high transmission in visible resign (> 85%), high hardness (7∼8H) , high adhesive force (7∼8) and low relative surface resistance (9.71 × 1011∼1.26 × 1010 Ω/cm2) with anti-electrostatic characters. For thermal resistance, the best Td value of epoxy/PMDA/AEAPS/Al2O3 is 378.6 °C which is 85.4 °C higher than that of neat epoxy resin. Physical properties of these materials are almost the same as those of the nanocomposites prepared from expensive colloid Al2O3. Evidences from TEM micrograph show that the inorganic additives are dispersed evenly in organic matrix with nanometer scale. [ABSTRACT FROM AUTHOR]

Two acids, 2( S )-[2( S )-ethylhexyloxy] propionic acid and 2( S )-[2( R )-ethylhexyloxy] propionic acid, were used as the chiral building block for the preparation of four liquid crystals 5, 6, 7 and 8 . The diastereomers of the biphenyl ring system, 5 and 6 , possess the phase sequence I-N * -SmC * -Cr1-Cr2, while the diastereomers of the naphthalene ring system, 7 and 8 , exhibit the sequence I-SmA-SmC * -Cr. The temperature ranges of the SmC * phase for 5 and 6 are wider than those for 7 and 8 ; the phase transition temperatures of the SmC * phase for 7 and 8 are lower than those for 5 and 6 . In the case of the diastereomers of naphthalene ring system, the larger the size of the lateral substituent at the second chiral centre, i.e. ethyl or methyl group, the wider the temperature range of the SmC * phase. [ABSTRACT FROM AUTHOR]

New organic-inorganic hybrid materials and their anti-electrostatic hybrid membranes are prepared via sol-gel process. The polycondensation of epoxy oligomers and AEAPS/Al2O3 complexes which are organically surface modified submicrometer aluminum trihydroxide inorganic fillers with an active aminoterminal silane coupling agent, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS), are performed. AEAPS enhances the interfacial interactions between the inorganic fillers and epoxy polymers. Meanwhile, this coupling agent maintains well dispersion of fillers in these composites. To improve the mechanical strength and thermal stability, pyromellitic dianhydride (PMDA) is used as curing agent. These hybrid films prepared from this method have excellent physical properties, such as UV-shielding, high transmission in visible resign (> 85%), high hardness (7∼8H) , high adhesive force (7∼8) and low relative surface resistance (9.71 × 1011∼1.26 × 1010 Ω/cm2) with anti-electrostatic characters. For thermal resistance, the best Td value of epoxy/PMDA/AEAPS/Al2O3 is 378.6 °C which is 85.4 °C higher than that of neat epoxy resin. Physical properties of these materials are almost the same as those of the nanocomposites prepared from expensive colloid Al2O3. Evidences from TEM micrograph show that the inorganic additives are dispersed evenly in organic matrix with nanometer scale. [ABSTRACT FROM AUTHOR]