Polymer scientist with extensive experience in design, synthesis and characterization of block and segmented copolymers and their structure-property behavior.
Abstract : Novel elastomeric polysiloxane modifiers for epoxy networks have been synthesized and ... more Abstract : Novel elastomeric polysiloxane modifiers for epoxy networks have been synthesized and characterized. In addition, curing studies of conventional epoxy resins incorporating these oligomers have been conducted. Structures were prepared having either epoxide, primary amine and/or secondary amine endgroups. The polymerization step for the siloxanes consisted of a base catalyzed equilibration of the appropriately functional disiloxane and octamethylcyclotetrasiloxane. In the case of hydroxy piperazine terminated modifiers, polymers were first synthesized with epoxy endgroups. These endgroups were then subsequently capped with an excess of piperazine prior to curing. The oligomers were characterized by FTIR, 'H and 13C NMR, GPC, endgroup analysis and vapor pressure osmometry. The secondary amine terminated oligomers basically act as linear modifiers. By contrast, the aminopropyl functional siloxanes produce a crosslinked network. Piperazine terminated oligomers show much better compatibility with the epoxy resins compared to the aminopropyl terminated oligomers.
... Claire Jalbert and Jeffrey T. Koberstein' Institute of Materials Science and Dep... more ... Claire Jalbert and Jeffrey T. Koberstein' Institute of Materials Science and Department of Chemical Engineering, University of Connecticut, Storrs, Connecticut 06269 ... and Pose+J developed a theory for the surface tension of polymer melts based upon the Cahn-Hilliard theory of ...
Abstract : Novel elastomeric polysiloxane modifiers for epoxy networks have been synthesized and ... more Abstract : Novel elastomeric polysiloxane modifiers for epoxy networks have been synthesized and characterized. In addition, curing studies of conventional epoxy resins incorporating these oligomers have been conducted. Structures were prepared having either epoxide, primary amine and/or secondary amine endgroups. The polymerization step for the siloxanes consisted of a base catalyzed equilibration of the appropriately functional disiloxane and octamethylcyclotetrasiloxane. In the case of hydroxy piperazine terminated modifiers, polymers were first synthesized with epoxy endgroups. These endgroups were then subsequently capped with an excess of piperazine prior to curing. The oligomers were characterized by FTIR, 'H and 13C NMR, GPC, endgroup analysis and vapor pressure osmometry. The secondary amine terminated oligomers basically act as linear modifiers. By contrast, the aminopropyl functional siloxanes produce a crosslinked network. Piperazine terminated oligomers show much better compatibility with the epoxy resins compared to the aminopropyl terminated oligomers.
... Claire Jalbert and Jeffrey T. Koberstein' Institute of Materials Science and Dep... more ... Claire Jalbert and Jeffrey T. Koberstein' Institute of Materials Science and Department of Chemical Engineering, University of Connecticut, Storrs, Connecticut 06269 ... and Pose+J developed a theory for the surface tension of polymer melts based upon the Cahn-Hilliard theory of ...
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