Viton® elastomer

Because of their widespread use in the American workplace, butyl rubber, nitrile latex, neoprene latex, poly(vinyl alcohol), surgical rubber latex, and Viton elastomer were chosen for the present studies. The composite/bonded substances of this study were not in all cases presently available as commercial material for protective garments, but rather were chosen to determine their potential for resistance to solvent permeation. Likewise, Teflon gloves were included in these studies simply because they are commercially available. 

Figure 7. Volume change of Viton elastomer as a function of time following immersion in 1,1,2-trichloroethane...

For the homogeneous, nonbonded materials evaluated in these studies (butyl rubber, neoprene latex, nitrile latex, polyethylene, polyvinyl alcohol), surgical rubber latex, and Viton elastomer), only the perlyVinyl alcohol) did not correlate well in this relationship. As has been shown in Fig. 6, most likely the polyethylene... 

Even if several articles and patents deal with the cotelomerisation or copolymerisation of HFP with other fluorinated olefins (e.g., with vinylidene fluoride leading to well-known Viton elastomers), its homotelomerisation is not so easy. This may come from the fact that hexafluoropropene is a monomer which... 

Fluorocarbon elastomers, particularly copolymers of HFP and VDF, are cross-linked by low-level y radiation (up to 20 Mrad) in the same fashion as PVDF. Radiation degradation of a VDF-HFP copolymer was studied by Zhong and Sun.35 Their finding was that there is a linear relationship between the dose and the weight loss of the polymer. Fluorocarbon elastomers based on copolymers of IFF and propylene were found to be more resistant to y radiation than Viton elastomers.36 Cross-linking of VDF-HFP, VDF-TFE, and tetrafluoroethylene-propylene (TFE/P) copolymers as well as of terpolymers VDF-HFP-TFE by ionizing radiation (gamma... 

The equilibrium shear compliances Je indicated at long times are all about 1.0 X lO" " Pa except for that of the PB-1 sample, which is unexpectedly somewhat higher. The fact that the PB-1 softening dispersion is found at shorter times than that of the PB-2 elastomer has to be attributed to its higher cis to trans ratio of placements, 0.80 as opposed to 0.67, which reflects a lower Tg. The fact that the rate of creep of the Viton elastomer is approximately five orders of magnitude slower in the softening dispersion than that of the PB-2 is believed to be a reflection of a T, which is 70°C higher. What is most unexpected is that... 

Benzene can be stored in any of the usual metals used for plant construction but attacks natural rubber, butyl rubber and neoprene. Viton elastomers can be used for gaskets and diaphragms. 

Probably the most famous of seal failures ever was the Challenger disaster which has been described in some detail by Lewis (71). This resulted from the effect of overnight low temperature on Viton elastomer. Perhaps most shocking is that this was a case where there had been several warnings of potential failure. 

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