Functionalization of SWCNTs and c.f.Grafting procedure and mechanical

characterization

Καθηγητής Koς.Α.ΠαϊπέτηςYπ.δι/κός Κ.Τσίρκα Ιωάννινα , Μάϊος 2015

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Cvd Attemt to create single wall nanotubes Catalyst Co,Fe

Gas acetylene

Temperature for 750 -800-850-900 °C

Time for 30-15-10 min

Substrate carbon fiber

Functionalization-grafting

Swcnt (1-3 nm) Carbon fiber

Dispersion processes• Sonicated for 2 hours (0.5 cycles -0.2 amplitude %) in ethanol-water-

acetone (0,7 % w/v functionalized swcnts Tuball)• Soaked via deep coating method for 30 minutes • Removed fibers • Air drying

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Experiments dispersion1. The best results were acquired with ethanol ,where large aggregates

strip-shaped – no dissolution were present during the first 45 minutes of sonication. Whereas the dispersion was successful after 90 mimutes.

good dispersion without big aggregates

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2. Acetone showed no dispersion, creation of aggregates and bubbles . t soni solubility

3. Water on the other hand presented some kind of dilution but not satisfactory enough.

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Monofilament manufactor1. 60 °C curing for 2 hours A SYSTEM 4-

=elastomeric 2. Cool down 25 °C 3. 120 °C post curing for 1h 30 min4. Cool down 25 °C B SYSTEM 100 -

12=brittle

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Fragmentation test with acoustic emission

• Thickness < 2 mm in the active length • Distance sensors 35 mm • Load cell 1 Klb• Velocity: 0.1mm/min

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Fragmentation test with photoelasticity

Results

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Processing results• C.F = carbon fiber – neat • G=grafted – with cnts• A= 4 ppw resin : 1 ppw hardener • B= 100 ppw resin : 12 ppw hardener

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As received

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After corrections

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Breakdown another 8 samples from each category for comparison Samples preparation for RAMAN Problems with dispersion – ethanol non repeatable

optimization under progress Analysis with SEM to calculate cnts % on fiber Fragmentation test -wait 30 minutes on drawing

Conclusions-Planning objectives