The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Nieck E. Benes - One of the best experts on this subject based on the ideXlab platform.
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The use of a star-shaped trifunctional Acyl Chloride for the preparation of polyamide thin film composite membranes
Journal of Membrane Science, 2018Co-Authors: Evelien Maaskant, Wouter Vogel, Theo J. Dingemans, Nieck E. BenesAbstract:Abstract A star-shaped trifunctional Acyl Chloride bearing ether linkages was synthesized as an alternative to the commonly used trimesoyl Chloride (TMC) in the preparation of polyamide thin film composite membranes (TFC). Although this star-shaped Acyl Chloride has the same functionality as TMC, it is larger in size and its Acyl Chloride groups are less reactive due to the electron donating ether linkages. In this work, we prepared TFC membranes by the interfacial polymerization of both this star-shaped Acyl Chloride and TMC with either one of the two structural isomers: m-phenylenediamine (MPD) or p-phenylenediamine (PPD). No strong effect was observed of the substitution pattern of the aromatic diamine on the membrane formation with TMC, due to the high reactivity of the Acyl Chloride groups of TMC. In contrast, the use of this star-shaped Acyl Chloride results in significant differences in the properties of the formed TFC membrane depending on the use of MPD or PPD. Where TMC-MPD membranes are well-known for their excellent retention, we could not obtain defect-free membranes prepared from MPD and this star-shaped triAcyl Chloride ( R rose bengal 77 % ). The use of PPD instead of MPD, however, did result in defect-free membranes ( R rose bengal > 97 % ) with an acceptable clean water permeance (2.5 L m−2 h−1 bar−1).
Evelien Maaskant - One of the best experts on this subject based on the ideXlab platform.
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The use of a star-shaped trifunctional Acyl Chloride for the preparation of polyamide thin film composite membranes
Journal of Membrane Science, 2018Co-Authors: Evelien Maaskant, Wouter Vogel, Theo J. Dingemans, Nieck E. BenesAbstract:Abstract A star-shaped trifunctional Acyl Chloride bearing ether linkages was synthesized as an alternative to the commonly used trimesoyl Chloride (TMC) in the preparation of polyamide thin film composite membranes (TFC). Although this star-shaped Acyl Chloride has the same functionality as TMC, it is larger in size and its Acyl Chloride groups are less reactive due to the electron donating ether linkages. In this work, we prepared TFC membranes by the interfacial polymerization of both this star-shaped Acyl Chloride and TMC with either one of the two structural isomers: m-phenylenediamine (MPD) or p-phenylenediamine (PPD). No strong effect was observed of the substitution pattern of the aromatic diamine on the membrane formation with TMC, due to the high reactivity of the Acyl Chloride groups of TMC. In contrast, the use of this star-shaped Acyl Chloride results in significant differences in the properties of the formed TFC membrane depending on the use of MPD or PPD. Where TMC-MPD membranes are well-known for their excellent retention, we could not obtain defect-free membranes prepared from MPD and this star-shaped triAcyl Chloride ( R rose bengal 77 % ). The use of PPD instead of MPD, however, did result in defect-free membranes ( R rose bengal > 97 % ) with an acceptable clean water permeance (2.5 L m−2 h−1 bar−1).
Theo J. Dingemans - One of the best experts on this subject based on the ideXlab platform.
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The use of a star-shaped trifunctional Acyl Chloride for the preparation of polyamide thin film composite membranes
Journal of Membrane Science, 2018Co-Authors: Evelien Maaskant, Wouter Vogel, Theo J. Dingemans, Nieck E. BenesAbstract:Abstract A star-shaped trifunctional Acyl Chloride bearing ether linkages was synthesized as an alternative to the commonly used trimesoyl Chloride (TMC) in the preparation of polyamide thin film composite membranes (TFC). Although this star-shaped Acyl Chloride has the same functionality as TMC, it is larger in size and its Acyl Chloride groups are less reactive due to the electron donating ether linkages. In this work, we prepared TFC membranes by the interfacial polymerization of both this star-shaped Acyl Chloride and TMC with either one of the two structural isomers: m-phenylenediamine (MPD) or p-phenylenediamine (PPD). No strong effect was observed of the substitution pattern of the aromatic diamine on the membrane formation with TMC, due to the high reactivity of the Acyl Chloride groups of TMC. In contrast, the use of this star-shaped Acyl Chloride results in significant differences in the properties of the formed TFC membrane depending on the use of MPD or PPD. Where TMC-MPD membranes are well-known for their excellent retention, we could not obtain defect-free membranes prepared from MPD and this star-shaped triAcyl Chloride ( R rose bengal 77 % ). The use of PPD instead of MPD, however, did result in defect-free membranes ( R rose bengal > 97 % ) with an acceptable clean water permeance (2.5 L m−2 h−1 bar−1).
Wouter Vogel - One of the best experts on this subject based on the ideXlab platform.
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The use of a star-shaped trifunctional Acyl Chloride for the preparation of polyamide thin film composite membranes
Journal of Membrane Science, 2018Co-Authors: Evelien Maaskant, Wouter Vogel, Theo J. Dingemans, Nieck E. BenesAbstract:Abstract A star-shaped trifunctional Acyl Chloride bearing ether linkages was synthesized as an alternative to the commonly used trimesoyl Chloride (TMC) in the preparation of polyamide thin film composite membranes (TFC). Although this star-shaped Acyl Chloride has the same functionality as TMC, it is larger in size and its Acyl Chloride groups are less reactive due to the electron donating ether linkages. In this work, we prepared TFC membranes by the interfacial polymerization of both this star-shaped Acyl Chloride and TMC with either one of the two structural isomers: m-phenylenediamine (MPD) or p-phenylenediamine (PPD). No strong effect was observed of the substitution pattern of the aromatic diamine on the membrane formation with TMC, due to the high reactivity of the Acyl Chloride groups of TMC. In contrast, the use of this star-shaped Acyl Chloride results in significant differences in the properties of the formed TFC membrane depending on the use of MPD or PPD. Where TMC-MPD membranes are well-known for their excellent retention, we could not obtain defect-free membranes prepared from MPD and this star-shaped triAcyl Chloride ( R rose bengal 77 % ). The use of PPD instead of MPD, however, did result in defect-free membranes ( R rose bengal > 97 % ) with an acceptable clean water permeance (2.5 L m−2 h−1 bar−1).
Jiaxi Xu - One of the best experts on this subject based on the ideXlab platform.
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do reaction conditions affect the stereoselectivity in the staudinger reaction
Journal of Organic Chemistry, 2006Co-Authors: Yikai Wang, Daming Du, Yong Liang, Lei Jiao, Jiaxi XuAbstract:The stereochemistry is one of the critical issues in the Staudinger reaction. We have proposed the origin of the stereoselectivity recently. The effects of solvents, additives, and pathways of ketene generation on the stereoselectivity were investigated by using a clean Staudinger reaction, which is a sensitive reaction system to the stereoselectivity. The results indicate that the additives, usually existed and generated in the Staudinger reaction, and the pathways of the ketene generation do not generally affect the stereoselectivity. The solvent affects the stereoselectivity. The polar solvent is favorable to the formation of trans-β-lactams. The addition orders of the reagents affect the stereoselectivity in the Staudinger reaction between Acyl Chlorides and imines. The addition of a tertiary amine into a solution of the Acyl Chloride and the imine generally decreases the stereoselectivity, which is affected by the interval between additions of the Acyl Chloride and the tertiary amine, and the imine s...
