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Chapter 9 Fracture behavior of polymers

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aDaYK cIC22 )/( σ=

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• Compact tension specimen (CTS)

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• Fracture surface of CTS speciemen of Cr(acac)3-toughening epoxy resins

TGDDM/DDS epoxy resin

TGDDM/DDS/1%Co(acac)3

TGDDM/DDS/1%Cr(acac)3

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• Proposed interaction mechanism between Cr(acac)3 and cured TGDDM/DDS network

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The cross section of unidirectional Gr/Ep laminates pareparedby (a) TGDDM/DDS, and (b) TGDDM/DDS/Cr(acac)3

The typical cross section of unidirectional Gr/Ep laminates

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Fiber bridging contribution

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IC

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ICo

EGKrσπσπ

==

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• The effect of crack speed on the measurement of fracture toughness for polymers

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• High speed fracture test (~3.4 m/s)

1.Izod impact test of polymers

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2. Charpy impact test of polymers

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Testing in water

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CTBN liqud rubber-toughening epoxy resins

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TEM micrographs of vacuum dried CSP’s

C0 CSP C3 CSP

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[±0o]4

[±90o]4

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