D4301-05 – Standard Test Method Technical Guide

📐 Scope and Significance of D4301

Standard Test Method D4301-05 (Reapproved 2019), under the jurisdiction of ASTM Subcommittee D01.33 on Polymers and Resins, outlines a procedure for the determination of total chlorine in epoxy resins and glycidyl ethers. The values stated in SI units are to be regarded as standard. The presence of residual chlorine in epoxy materials is deleterious to the final product properties. This test method has been validated for resins and ethers with total chlorine contents ranging from 50 ppm to 35% by weight. Other halogen compounds will react with the analytical reagent, but they are effectively distinguished from chlorine by the final potentiometric titration. It is important to note that epoxy and other functional groups will consume the reagent without affecting the accuracy of the chloride determination.

⚙️ Test Procedure and Apparatus Requirements

The method summary describes dissolving the material in an inert solvent like dimethoxyethane (DME) and reacting it with sodium biphenyl to convert bound organic chlorine into water-soluble chloride. Excess reagent is decomposed with isopropyl alcohol. The chloride ion is then titrated potentiometrically with silver nitrate. Key apparatus required includes a potentiograph, a suitable beaker and buret, and a magnetic or paddle stirrer. All reagents must be reagent grade chemicals conforming to the specifications of the American Chemical Society. Reagent water must conform to Type II of Specification D1193.