Does anyone have a decent spec sheet for this material that includes the shear Modulus or Modulus of elasticity? It is using a phenolic resin.
6781 is an 8 harness satin weave of S-2 glass fiber. As a dry fabric it has no shear modulus. As a composite the shear modulus would be determined mainly by the resin properties.
6781 is the identical to 7781 except for the use of S2-glass rather than E-glass (most just call it S-glass but the original S-glass, which was qualified to a number of defense and ballistic missile programs, is no longer made. S2 is made to commercial specifications rather than military, just like E-glass. You can easily find information through a google search.
As for phenolic resin, you need to know the exact proprietary product formulation for properties. Resin properties can be all over the map and depends on the exact formulation and processing. You can generally only get that from the manufacturer. SC-1008 is one of the most common phenolics used in aerospce composites. This resin can be used straight out of the drum or with additives.
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