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 physical and elastomeric properties of several DEXSIL 300 (10-SiB-3) samples were investigated. Modulus - temperature studies were used to determine the glass transition temperature Tg, the melting temperature Tm, and the oxidative crosslinking temperature Tox. Stress relaxation in air at elevated temperatures was used to compare the oxidative stability of the various formulations. It was found that the Tg of DEXSIL 300 is some 30°C lower than that of DEXSIL 200 (10-SiB-2) polymers, extending the elastomeric properties of DEXSIL 300 to lower temperatures. At high temperatures, both silica filler and ferric oxide are found to increase Tox to an ultimate value of 320°C. The effects of cure were also investigated, and γ-radiation-cured samples exhibit a slight degree of crystallinity with a melting temperature Tm = +40°C. No crystallinity was detected in similar peroxide-cured samples. Stress relaxation results are presented in support of the modulus - temperature studies. Formulations with a low Tox show oxidative effects earlier than those with a higher oxidation temperature. Silica-and ferric oxide-filled samples exhibit improved oxidative stability, as do samples filled with diphenylsilanediol.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1972.070161009
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