ISSN:
1436-2449
Keywords:
Intrinsic viscosities
;
osmotic pressures
;
unperturbed dimensions
;
characteristic ratio
;
chain stiffness
;
poly(tetramethyl-p-silphenylene-siloxane)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Summary Experimental values of the characteristic ratio of the unperturbed dimensions of poly (tetramethyl-p-silphenylene-siloxane) were obtained from intrinsic viscosities and osmotic pressures. It was found that the characteristic ratio of this polymer is 1.55±0.30 when the phenylene group is treated as a virtual bond, and 4.51±0.40 when the individual bonds in the phenylene group are taken into account separately. This value is unexpectedly low, considering the usual stiffening effect of the p-phenylene group. Apparently this group can also have a “buffering” effect which decreases stiffness, by reducing interactions among the atoms or groups preceding it and succeeding it along the chain backbone.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00329967
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