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Polymer Chemistry Commons

Open Access. Powered by Scholars. Published by Universities.®

1997

Materials Science and Engineering

Articles 1 - 2 of 2

Full-Text Articles in Polymer Chemistry

Correlation Of Dynamic Dielectric Properties To Reaction Kinetics And Changing Mechanical Properties Of Epoxy Resins During Cure, Yunfei Wang Jan 1997

Correlation Of Dynamic Dielectric Properties To Reaction Kinetics And Changing Mechanical Properties Of Epoxy Resins During Cure, Yunfei Wang

Dissertations, Theses, and Masters Projects

The principal objective of this paper is to describe how complex impedance, obtained from frequency dependent dielectric sensing technique, can be used as an effective diagnostic tool for in situ real-time investigation in the fabrication of thermoset structures.;Two epoxy systems (Pr500 from 3M and My720 from Ciba Geigy) with different functionality are characterized in terms of their dielectric, thermal, and rheological behavior. It is observed that there is a one to one relationship between Tg and conversion which is independent of cure temperature. The chemical kinetics of the reaction is satisfactorily described by an autocatalyzed reaction mechanism. The chemical rate …


The Synthesis Of Reflective And Electrically Conductive Polyimide Films Via An In Situ Self-Metallization Procedure Using Silver(I) Complexes, Robin Elaine Southward Jan 1997

The Synthesis Of Reflective And Electrically Conductive Polyimide Films Via An In Situ Self-Metallization Procedure Using Silver(I) Complexes, Robin Elaine Southward

Dissertations, Theses, and Masters Projects

Optically reflective polyimide films have been prepared by the incorporation of silver(I) acetate and a {dollar}\beta{dollar}-diketone solubilizing agent, hexafluoroacetylacetone (HFAH), into a dimethylacetamide solution of the poly(amic acid) formed from {dollar}3,3\sp\prime,4,4\sp\prime{dollar}-benzophenonetetracarboxylic acid dianhydride (BTDA) and {dollar}4,4\sp\prime{dollar}-oxydianiline {dollar}(4,4\sp\prime{dollar}-ODA). Optically reflective and conductive polyimide films have been prepared by replacing the {dollar}\beta{dollar}-diketone (HFAH), with the less substituted {dollar}\beta{dollar}-diketone, trifluoroacetylacetone (TFAH). The former system has been both cast directly from the poly(amic acid) resin and cast from the poly(amic acid) resin onto a fully imidized {dollar}\rm BTDA/4,4\sp\prime{dollar}-ODA base (forming a metallized topcoat). Thermal curing of the silver(I)-containing poly(amic acid) leads to imidization with …