Type of Document Master's Thesis Author Noell, John Lee Watson URN etd-08012012-040155 Title The preparation and characterization of PEK/TEOS glasses by the sol-gel method Degree Master of Science Department Chemical Engineering Advisory Committee
Advisor Name Title Wilkes, Garth L. Committee Chair Conger, William L. Committee Member Gibson, Harry W. Committee Member Keywords
Date of Defense 1987-07-05 Availability restricted AbstractOver the last twenty years, substantial emphasis has been placed on the development
of a new class of inorganic glasses using the sol-gel approach. This technique utilizes metal
alkoxide precursors such as tetraethylorthosilcate (TEOS) to build an inorganic glass matrix
out of solution by a two step poly(hydrolysis-condensation) reaction mechanism. The benefits
of making ceramics by this method include considerable energy savings due to the lower
sintering temperatures required to form the densified glass and the ability to produce multi-component
amorphous materials that can not be made through the traditional firing processes.
As a result of this last possibility, polymer researchers have sought to develop spin-off
hybrid inorganic-organic network systems that can be prepared by the sol-gel method using
reactively functionalized oligomers and/or monomers along with the metal alkoxide precursors.
These types of organically modified multi-component glasses could have enormous potential
from an applications standpoint because the system’s mechanical and physical
features can be tailored in accordance to the organic and polymeric materials chosen.
One such inorganic-organic system prepared by this procedure is the new PEK/TEOS
glasses. The PEK represents the bisphenol-A polyarylene ether either ketone thermoplastic
polymer endcapped with triethoxysilane functional groups. By mixing the PEK and
TEOS components at different weight compositions in the starting sol-gel reaction solution,
change in the mechanical properties is observed as the TEOS content is increased for the final,
thin film glasses. Also, a poor extent of reaction or degree of incorporation of the PEK
oligomer is revealed which has been attributed to the vitrification of the glass before the PEK
endgroups have a chance to react. To alleviate this problem, thermal treatments are employed
to further the sol-gel reaction and to complete the network formation in the PEK/TEOS
glasses. After the thermal treatments, the change in the mechanical and physical properties are monitored, and the data retlects systematic trends in regards to the TEOS content and the
temperature of the thermal treatment utilized. In addition to these results, some speculative
information is provided on the temperature sensitivity and the rate of curing of the PEK/TEOS
glasses during the thermal treatments.
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