ASTM D3591 is the ASTM standard that addresses the determination of the logarithmic viscosity number of poly(vinyl chloride) (PVC) in formulated compounds. It is used to measure a key solution-property indicator associated with the polymer content in a prepared compound, helping support consistent material evaluation and quality control. For buyers and laboratories working with PVC formulations, this technical document provides a defined test approach that can improve comparability, documentation, and compliance-focused decision-making.

ASTM D3591 standard overview

ASTM D3591, titled Standard Test Method for Determining Logarithmic Viscosity Number of Poly(Vinyl Chloride) (PVC) in Formulated Compounds, provides a standardized way to assess a viscosity-related property of PVC within formulated compounds. The method is intended to support repeatable testing and consistent reporting when evaluating material characteristics tied to the polymer component. As an ASTM standard, it helps establish a common technical basis for laboratories, suppliers, and purchasers that need a reliable reference for PVC compound assessment.

Where is ASTM D3591 used?

This standard is commonly used in laboratory and quality control settings that test formulated PVC compounds. It is relevant wherever a defined method is needed to evaluate the logarithmic viscosity number of the PVC component in a compound, such as during incoming material checks, product development, or batch verification. ASTM D3591 is especially useful in workflows that require consistent test results for comparing compounds, documenting material properties, or supporting technical specifications for PVC-based products.

Practical importance of ASTM D3591

ASTM D3591 matters because it helps standardize how a viscosity-related PVC property is measured and reported. That consistency can reduce variability between test results, support procurement decisions, and improve confidence in product evaluation. For organizations handling formulated PVC compounds, using a recognized ASTM standard can also aid compliance efforts and internal quality assurance. In practice, it gives stakeholders a clearer basis for comparing materials and confirming that testing is performed in a controlled, repeatable way.

• Logarithmic viscosity number determination
• Formulated PVC compound evaluation
• Consistent laboratory testing
• Quality control and reporting support
• Technical reference for material comparison