本文件规定了根据折射率与苯乙烯质量分数百分比表，通过与提取样品的测量折射率相关，测定乳液聚合丁苯橡胶（SBR）中结合苯乙烯含量的方法。 该方法也适用于提取的充油乳液聚合丁苯橡胶，只要其产生适合折射率测量的薄膜。不适用于溶液聚合丁苯橡胶。

This document specifies a method for determining the bound styrene content of emulsion-polymerized styrene-butadiene rubbers (SBR) by correlation with the measured refractive index of an extracted sample according to a table of refractive indices versus percentage mass fractions styrene. The method is also applicable to extracted oil-extended emulsion-polymerized SBR as long as it produces a film suitable for refractive index measurements. It is not applicable to solution-polymerized SBR.