Speaker:

Date/Time:

Price:

$30 Members; $20 Students, Retirees, Life Members; $35 nonmembers

Location:

Reservations:

Contact Alice Totten by Friday, May 9th with your dinner option below:

Email (preferred):  alicetotten@aol.com

Phone:  (206) 427-8825

Dinner Options:

• Salmon
• Chicken
• Vegetarian

Peter Kazarinoff
Graduate student, Materials Science & Engineering, UW
Energy Levels and Charge Carrier Mobility in Carboxylate Functionalized Polythiophenes

Organic semi-conducting polymers have been the subject of intense study during the last couple of years. These materials are alternatives for conventional silicon based semiconductors in low cost, easy to manufacture electronic devices such as thin film transistors and solar cells.  Three semi-conducting polythiophene based polymers have been synthesized with electron withdrawing carboxylate substituents. They provide better air stability, compared to other semi-conducting polymers, due to a decreased HOMO (highest occupied molecular orbital) by 0.5eV. These polymers still exhibit high charge carrier mobility averaging 0.01 cm²/Vs in thin-film transistors fabricated entirely in air.

Jason Zhou
Senior, Materials Science and Engineering, UW
Study of Rigid Natural Fibers-Lessons for New Composites

Spicule fibers of the siliceous sponge Euplectella aspergillum were studied under torsional loading to determine the mechanical response of this concentrically-ringed structure. Laser confocal scanning microscopy and scanning electron microscopy have clarified the damage mechanisms in these natural rigid composite systems. The results have confirmed the controlling roles of thin protein layers, and the complex architecture of such sponges in structural toughening. It is expected that this work will lead to new design composite configurations for normally brittle materials, such as undersea optical cables.

Conor D. Keenan
Senior, Materials Science and Engineering, UW
Using an Instrumented Rapid Adhesion Test (I-RAT) to Obtain a Comparative Measure of Bond Strength

The Rapid Adhesion Test (RAT) originated as a test method that was modified from a metal-to-metal peel test.  It is used to quickly and inexpensively assess the mode of failure of a composite bond.  Initially designed to produce a qualitative measure of the failure mode representing bond quality, the test can be performed with 90% less cost and flow time as compared to the industry standard of composite bond analysis by the Double Cantilever Beam (DCB) test.  In order to obtain more quantitative data from the RAT test method the Instrumented Rapid Adhesion Test (i-Rat) was developed by the Flinn group at the University of Washington.  This modified test method incorporates the use of a Climbing Drum Peel (CDP) fixture with bonded samples that were originally intended for manual RAT testing.  This innovative modification to the RAT method allows us to produce a comparative measure of bond strength using the peel torque data obtained during testing of the bonded composite.  Different composite/adhesive/peel ply combinations in a composite bond can therefore be ranked according to their bond strength in a very quick and inexpensive method to help determine the best choice for a certain application