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2. Place the pre-cured polymer under house vacuum in order to remove any
interstitial air. Remove when bubbling has ceased (~ 10 minutes).
3. Introduce a free-standing mat of A-CNTs by placing it on top of the pre-cure,
and "scoop" some of the polymer onto the top of the forest to promote
infiltration.
4. After fully submerged, place the infiltrating composite under a vacuum of 1
Torr for at least 3 hours until bubbling has ceased.
5. When no longer bubbling, subject the sample to 1 hour of 100 0C heat
treatment as recommended by the manufacturer to ensure complete curing.
This preparation technique was used for both types of A-CNTs grown via the
previously-mentioned CVD techniques. The next sections will address the results
from these attempts in creating A-CNT composites.
3.2.1. Results from Pre-Deposited Catalyst A-CNT Infiltration
As mentioned previously, the pre-deposited catalyst A-CNTs are
predominantly thin-walled CNTs, with the majority being DWNTs. After numerous
attempts at infiltration, it was repeatedly observed that these relatively flimsy CNT
forests were not able to maintain their alignment during infiltration, and would
"crumple" as the polymer infiltrated. As the curing agent is dispersed in the
monomer prior to infiltration, there is a finite time where the polymer will have the
fluidity to infiltrate the forest before it becomes too viscous and eventually solidifies
due to the crosslinking. Coupled with the high viscosity of the Sylgard 184
monomer, successful infiltration of these relatively delicate forests seems