Dynamic Mechanical Thermal Analysis (DMTA) tests were conducted on 50 _ 10 _3mm3 samples with a DMS 6100 (Seiko Instruments Inc., Japan) in double cantilever (bending) mode. In these tests, the storage modulus E0 (elastic response) and loss modulus E00 (viscous response) of polymers are measured as a function of temperature (or frequency) as the polymer is deformed under an oscillatory load (stress).