Structure/property behavior of inorganic/organic sol-gel derived hybrid materials

A novel class of inorganic/ organic hybrid materials referred to as CERAMERs have been successfully prepared by a sol-gel process using a polymeric acid catalyst, poly(styrene sulfonic acid), to form a network from tetraethylorthosilicate (TEOS) and triethoxysilane end capped oligomers of poly( tetramethylene oxide) (PTMO). The structure-property relationships were determined for these hybrid networks from their dynamic mechanical behavior, mechanical properties, and SAXS behavior. Thermal gravimetric data coupled with FfIR analysis were used to obtain a qualitative measure of the extent of conversion of the metal alkoxides as a function of acid catalyst. Another new class of CERAMERs was successfully developed by the sol-gel processing of three different metal alkoxides in conjuction with the triethoxy silane end capped PTMO oligomers. The first novel hybrid is based upon complexes of aluminum tri-n-butoxide with ethyl acetoacetonate or titanium tetra-iso-propoxide with ethyl acetoacetate reacted with the triethoxysilane end capped PTMO. The hybrid networks were optically clear and could be easily formed as relatively large monoliths. A novel method of preparation of stable sols without the use of ethyl acetoacetate, developed by Dr. Bing Wang in this laboratory, led to more stable CERAMERS of titanium tetra-iso-propoxide (TiOPr) reacted with the functionalized P'TMO as well as a fourth inorganic/organic hybrid material based upon zirconium tetra-n-propoxide and PTMO. Indeed, the mechanical properties of the TiOPr/P'TMO CERAMERs and ZrOPr/P'TMO CERAMERs were significantly enhanced over the TEOS/PTMO CERAMERs in terms of both Young's modulus and stress at break. The structure-property relationships of these materials were adequately described by the morphological model originally developed for the CERAMERs based upon TEOS/PTMO.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Materials Engineering Science

Department dc:contributor.department

Materials Engineering Science

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1990

Author dc:creator

• Brennan, Anthony Bartholomew

Chair dc:contributor.committeechair

• Wilkes, Garth L.

Committee members dc:contributor.committeemember

• David, Mark E.
• King, Russell K.
• McGrath, James E.
• Ward, Thomas C.

• polyimidesno

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-09162005-115036

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/39379