ISSN:
1435-1536
Keywords:
Polycarbonates
;
molecular motions
;
2H NMR
;
tensile stress
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Deuteron NMR was utilized to study phenylene group motions in glassy polycarbonate (PC) as a function of tensile stress and chemical modification. A special stretching device was constructed allowing the application of forces up to 1500 N during the measurement. While cold drawing of PC effects motional restrictions equivalent to a temperature shift of 10 K, a reversible strain near the yield point enhances the ring dynamics slightly. Methyl group substitution at the ortho positions gives rise to even more constraints, shifting the onset of fast ring flips by about 180 K.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00657388
Permalink
