ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
The temperature dependence of the dynamic mechanical properties of dicumyl peroxide/sulfur vulcanizates of seven members of the poly(vinyl alkyl ether) series of elastomers has been determined. The relative position of the curves, relating the dynamic resilience to the dynamic modulus of these polymers, was generally in the order of their glass transformation temperatures (Tg). The dynamic mechanical property data on poly(vinyl n-pentyl ether) and poly(vinyl 2-ethylhexyl ether), which have the same Tg, fall on a common curve characteristic of the temperature of measurement. The dynamic resilience versus dynamic modulus curves are displaced towards higher dynamic resilience and usually lower dynamic modulus values as the temperature of measurement is increased. Poly(vinyl isobutyl ether) and poly(vinyl ethyl ether) show a larger temperature coefficient of resilience than do the other poly(vinyl alkyl ethers), which also include the n-butyl, n-hexyl, and n-octyl members. Apparently, the Tg is a major factor in correlating the dynamic mechanical behavior of this homologous series of elastomers. The size and shape of the alkyl group appear to be reflected primarily in their effect on the Tg. Poly(vinyl isobutyl ether) was the only member of the series showing any anomalies in dynamic mechanical properties that might be ascribed to structure. Because the dynamic resilience of various poly(vinyl alkyl ether) vulcanizates, possessing the same concentration of chemical crosslinks, correlate better with their degree of polymerization than with their molecular weight it appears that the dynamic resilience depends more on the length of the free chain ends than it does on their mass or volume.
Additional Material:
12 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1965.070091024
