Aerospace series. Fluorosilicone rubber (FVMQ). Hardness 80 IRHD

2015 ◽  
Keyword(s):  
Fluorosilicone Rubber

Accelerated Heat-Aging Studies on Fluorosilicone Rubber

1975 ◽  
Vol 48 (5) ◽  
pp. 944-952 ◽  
Author(s):  
S. H. Kalfayan ◽  
R. H. Silver ◽  
A. A. Mazzeo
Keyword(s):  
Weight Loss ◽  
Stress Relaxation ◽  
Repeat Unit ◽  
Accelerated Aging ◽  
Basic Mechanism ◽  
Inert Atmosphere ◽  
Polymer Backbone ◽  
Aging Studies ◽  
Relaxation Measurements ◽  
Fluorosilicone Rubber

Abstract The accelerated aging of a vulcanizate of fluorosilicone rubber was studied by four methods: infrared spectroscopy, GPC, weight loss, and stress relaxation, with the object of gathering information pertinent to understanding the basic mechanism of its aging. No changes were observed in infrared spectra of the rubber aged in air up to 315°C although severe degradation took place, as evidenced by high weight loss and drastic change in the physical condition of the test samples. It was concluded that although the polymer degrades, there is no change detectable within the precision of the analytical methods in the structure of the repeat unit of the elastomer. The gel-permeation chromatogram of unheated rubber showed peaks at MW 450 000 (95%) and 630 (5%). The low-molecular-weight component is very likely the cyclic tetramer of λ,λ′,λ″-trifluoropropylmethylsiloxane, the principal monomer of the FVMQ used. Heat aging increased the concentration of the 630 MW component, but rate studies were prevented by complications resulting from solvent-induced rubber degradation. Rapid decrease in the MW of FVMQ, as found by GPC, indicated random scission in the polymer backbone, as opposed to ordered unzipping of the repeat unit. The same conclusion was reached from the effects of crosslink density on stress relaxation. Activation energies obtained from weight-loss measurements (104 kJ/mol) were lower than those obtained from stress-relaxation measurements, (150–155 kJ/mol), suggesting that the processes being measured in each case may not be the same. Chemical stress relaxation takes place more rapidly in the presence of air than in an inert atmosphere, and intermittent stress-relaxation measurements indicate that crosslinks form during thermal aging in air, their rate first increasing and then decreasing.

Study on the friction properties of nanocopper oxide/fluorosilicone rubber

2020 ◽  
Vol 138 (13) ◽  
pp. 50120
Author(s):  
Xiaoping Yang ◽  
Jianfeng Tian ◽  
Jun Dong
Keyword(s):  
Fluorosilicone Rubber

Study on high‐temperature composite properties of fluorosilicone rubber with nano‐Sb 2 O 3

2020 ◽  
Vol 137 (42) ◽  
pp. 49302 ◽  
Author(s):  
Zehua Xu ◽  
Yanbin Zhang ◽  
Jin Zhou ◽  
Ming Qi ◽  
Jianyong Shi ◽  
...  
Keyword(s):  
High Temperature ◽  
Composite Properties ◽  
Fluorosilicone Rubber

Fluorosilicone Rubber

1960 ◽  
Vol 52 (9) ◽  
pp. 783-784 ◽  
Author(s):  
O. R. Pierce ◽  
G. W. Holbrook ◽  
O. K. Johannson ◽  
J. C. Saylor ◽  
E. D. Brown
Keyword(s):  
Fluorosilicone Rubber
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