The bound styrene test is a measure of the bound monomeric composition of the rubber. It is used as a check on the accuracy of monomer charging and also as a guide to the uniformity of the product, since the bound styrene content affects the physical properties.

1.1 This test method covers the determination of styrene content, and is intended for general use on solid uncompounded styrene-butadiene copolymers, commonly referred to as SBR, prepared by the emulsion process. SBR polymers prepared in solution will require the use of different refractive index tables because the vinyl content of the butadiene differs from that in the emulsion polymers. It is applicable to polymers having less than 55 % bound styrene.

Note 1—The nomenclature used in this test method is in accordance with Practice D 1418.

1.2 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.