ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Rheo-optical and mechanical properties of Cyclic Olefin Copolymers(COC’s) withdifferent composition have been investigated across the glass transition temperature. Accuratemeasurement of stress or strain-optical coefficients and elastic modulus data across the glasstransition are essential for predicting optical anisotropy in many optical products like pickuplenses and waveguides in LCD backlight unit since the material of these products have bothflow and thermal history from the melt to glass. To obtain stress-optic behavior in the widefrequency region including rubbery, glassy and glass transition regime, extensional bar-typedevice was used. A shear-sandwich tool was used in the melt region. Master curves formodulus, stress-optical and strain-optical coefficients have been obtained in wide frequencyregion. The stress-optical coefficients of COC’s with mol fraction of norbornene, 60 ~ 70%,showed almost constant between -8 and -9 Br at glassy region and between +920 and +1,160Br in the melt region. Even though the glass transition temperature showed the difference of35[removed info], the stress-optical coefficients of COC’s with different composition showed almostsame extreme values
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/52/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.326-328.183.pdf
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