Test Methods For Aerospace Sealants Two-Component Synthetic Rubber Compounds

Abstract An investigation of the effect of varying conditions of high-temperature exposure has shown that, at a constant temperature, the supply of oxygen is the principal factor which causes stiffening of the vulcanizates. The loss of volatile plasticizers, when present, also contributes to the stiffening. The test-tube technique, developed in the course of this investigation, in which dumbbell samples are suspended in stoppered test-tubes (38 by 300-mm.) heated by immersion in an oil bath, appears to give results which are considerably more duplicable than those obtained by the usual aging in circulating air ovens. The test-tube technique also gives somewhat better differentiation between good-heat aging and poor-heat aging compounds. The rate of deterioration as measured by elongation change is doubled for an 18° F increase in the exposure temperature. As measured by hardness change the rate is doubled by an increase of 42° F. Tests run at 250° F by this method are no more reproducible than those run at 300° F.

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Rubber Or Synthetic Rubber Compounds Coolant Resistant (55-65)

10.4271/ams3211 ◽

1942 ◽

Author(s):

Keyword(s):

Synthetic Rubber ◽

Rubber Compounds

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Problems Concerned with the Physical Testing of Vulcanizates

Rubber Chemistry and Technology ◽

10.5254/1.3542579 ◽

1956 ◽

Vol 29 (3) ◽

pp. 1082-1106 ◽

Cited By ~ 5

Author(s):

Primus Kainradl

Keyword(s):

Test Methods ◽

Rubber Compounds ◽

Physical Testing ◽

New Apparatus ◽

The Creation ◽

State Of Affairs ◽

Critical Consideration

Abstract A critical consideration shows that the test methods in current use for vulcanizates often fail to make possible a reliable decision about different rubber compounds out of a series of development formulations with respect to their evaluation for subsequent use. The tester by himself is not in a position to bring about an improvement in this unsatisfactory state of affairs, since this cannot be accomplished by the improvement of existing methods alone or by the creation of a new apparatus. A closer cooperation between the fields of testing and application is necessary.

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Test Methods for Hyperelastic Characterization of Rubber4

Tire Science and Technology ◽

10.2346/1.3138763 ◽

2009 ◽

Vol 37 (3) ◽

pp. 165-186 ◽

Cited By ~ 3

Author(s):

R. Kupchella ◽

J. Kidney ◽

W. Hutchison

Keyword(s):

Three Dimensional ◽

Test Methods ◽

Biaxial Stress ◽

Image Correlation ◽

Optical Methods ◽

Filled Rubber ◽

Rubber Compounds ◽

Stress States ◽

Property Changes

Abstract Optical methods using digital image correlation (DIC) are utilized in developing rubber constitutive tests. Two and three dimensional DIC systems are employed to measure strains on rubber specimens subjected to uniaxial, planar, and biaxial stress states. A special membrane inflation test was developed and is described for providing the biaxial constitutive data. Deformation-induced material property changes for the three modes of testing are quantified using a concept based on energy dissipation. The constitutive test strain ranges for each of the three modes are separately selected to equalize the material states. The methodology is applied to filled rubber compounds in order to characterize them in terms of hyperelastic behavior. Evaluation and comparison of several common hyperelastic models are given, and application to finite element modeling of a structural rubber specimen is described.

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