This test method can be used to obtain the matrix content or matrix solids content. Knowledge of the matrix content or matrix solids content is useful in developing optimum manufacturing processes. Where volatiles content is consistent and not critical to process, matrix content shall be used.

This test method is limited to reinforcement constituents that do not lose or gain weight upon exposure to solvent and matrix constituents that do not dissolve in the solvent. Alternative methods or solvents should be used or an agreement should be made with the end user for how to consider the effect of incomplete matrix dissolution or reinforcement weight change for reporting purposes.

1.1 This test method covers the determination of the matrix solids content and matrix content of composite material prepregs. Volatiles content, if appropriate and required, is determined by means of Test Method D 3530/D 3530M.

1.2 This test method focuses on thermosetting matrix material systems for which matrix may be extracted in organic solvent. However, other, unspecified reagents may be used with this test method to extract other matrix material types for the same purposes.

1.3 This test method does not distinguish between hybrid reinforcements or matrices. Its use with hybrids is limited to a determination of total reinforcement or matrix, or the use of a standard factor to be used as the weight of a particular reinforcement or matrix constituent.

1.4 Alternate techniques for determining matrix and reinforcement content include Test Methods C 613/C 613M (Soxhlet extraction) and D 3171 (meant typically for laminates; covering matrix digestion or combustion).

1.5 The values stated in SI units are to be regarded as standard.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary information is given in 8.2.4 and 8.2.5