1.1 本试验方法包括测定未经处理的无油和无色素SBR和NBR的稀溶液粘度（DSV）、凝胶特性和溶胀指数。 1.2 本试验方法可用于测定SBR和NBR以外橡胶的DSV和凝胶特性，但可能需要2-丁酮和甲苯以外的溶剂。 1.3 本试验方法不适用于微凝胶的测量。 1.4 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.5 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 4.1 这些测试对于合成橡胶生产中的质量控制特别有用。 4.2 凝胶百分比是所选溶剂中不溶性橡胶含量的量度。在某些橡胶中可能有意引入凝胶。与正常水平相比的变化表明聚合体系发生了变化。 4.3 溶胀指数是衡量凝胶类型的指标。具有低膨胀指数的凝胶被称为“硬凝胶”，通常表示存在不易通过研磨分解的材料。 高溶胀指数通常表示存在“松散凝胶”，该凝胶可通过研磨轻易分解。 4.4 在低凝胶或无凝胶橡胶中，DSV与分子量直接相关。由于粘度仅在橡胶的可溶性部分上测量，因此使用DSV来预测具有高凝胶值的橡胶中的分子量是没有意义的。

1.1 This test method covers the determination of the dilute solution viscosity (DSV), the gel characteristics, and the swelling index of raw non-oil-extended and non-pigmented SBR and NBR. 1.2 This test method may be used to determine the DSV and gel characteristics of rubbers other than SBR and NBR, however, solvents other than 2-butanone and toluene may be required. 1.3 This test method is not intended for the measurement of micro-gel. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 These tests are particularly useful for quality control in the production of synthetic rubbers. 4.2 Percent gel is a measure of the amount of insoluble rubber present in the chosen solvent. Gel may be introduced intentionally in some rubbers. Variations from a normal level indicate changes in the polymerization system. 4.3 Swelling index is a measure of the type of gel. Gel with a low-swelling index is referred to as “hard gel” and usually indicates the presence of material that does not break down readily by milling. A high-swelling index normally indicates the presence of a “loose gel” that may be broken down easily by milling. 4.4 In low-gel or gel-free rubbers, the DSV correlates directly with the molecular weight. Since the viscosity is measured only on the soluble portion of the rubber, the use of DSV to predict molecular weight in rubbers having high gel values is meaningless.