Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D3128-07 – Standard Test Method Technical Guide
📜 Standard Designation, Scope, and Application
The ASTM standard D3128-07 (Reapproved 2021), officially designated as “Standard Specification for 2-Methoxyethanol,” establishes the mandatory chemical and physical property requirements for this solvent. The standard is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and has been approved for use by agencies of the U.S. Department of Defense. All values stated in SI units are to be regarded as standard.
It is important to note that this specification focuses strictly on product properties. It does not purport to address all safety concerns associated with its use. Users are directed to consult the supplier’s Material Safety Data Sheet (MSDS) for comprehensive hazard information and to determine the applicability of regulatory limitations prior to use.
📊 Specification Requirements for 2-Methoxyethanol
Section 3 of the standard defines the specific property limits the material must conform to. For determination of conformance, observed or calculated values must be rounded to the nearest unit in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29.
| 🟦 Property | 📏 Requirement | 🎯 Referenced Test Method |
|---|---|---|
| Apparent Specific Gravity (20/20°C) | 0.963 to 0.967 | D4052 |
| Apparent Specific Gravity (25/25°C) | 0.960 to 0.964 | D4052 |
| Color, Pt-Co Scale (max) | 15 | D1209 or D5386 |
| Distillation – Initial Boiling Point (min) | 123 °C | D1078 |
| Distillation – Dry Point (max) | 126 °C | D1078 |
| Water Content (weight %, max) | 0.2 | D1364 |
| Acidity as Acetic Acid (weight %, max) | 0.01 (equiv. 0.093 mg KOH/g) | D1613 |
✅ Conformance and Rounding Rule: For determining conformance with this standard, all observed or calculated values must be rounded “to the nearest unit” in the last right-hand digit of the specification limit per Practice E29. For example, a water content value of 0.24% rounds to 0.2%, which is within the specification.
⚙️ Test Methods and Quality Control
Compliance with the specification is verified through a suite of ASTM test methods. Sampling of the chemical shall be conducted in accordance with Practice E300, and packaging must comply with U.S. Federal Standard PPP-C-2020. The specific gravity is determined using a digital density meter per D4052, while distillation range is verified using Test Method D1078. The very tight 3 °C boiling range (123 °C min to 126 °C max) is a key indicator of the solvent’s purity.
Acidity is tightly controlled to a maximum of 0.01 weight percent as acetic acid (equivalent to 0.093 mg KOH per gram of material), measured by Test Method D1613. The maximum water content of 0.2 weight percent is determined using the Karl Fischer titration method (Test Method D1364).
💡 Note on Color Measurement: While Test Method D1209 (Visual Pt-Co Scale) is the primary method, instrumental colorimetry using Test Method D5386 is also permitted. The standard states that the instrumental method has shown no statistically significant difference from the visual method, although 2-methoxyethanol was not part of the specific interlaboratory study set used for the correlation.
⚠️ Withdrawn References: Users should be aware that Guide D268 (Sampling and Testing Volatile Solvents) and Test Method D1364 (Water in Volatile Solvents) have been withdrawn by ASTM. Alternative validated methods or supplier specifications should be consulted for water content determination if the historical methods are no longer available.
❓ Frequently Asked Questions
🔍 What is the official designation and scope of ASTM D3128?
The official designation is ASTM D3128-07 (Reapproved 2021). Its scope is specifically limited to establishing the standard property requirements for the chemical 2-methoxyethanol (ethylene glycol monomethyl ether).
💡 What are the specific gravity limits for this solvent?
The apparent specific gravity must be between 0.963 and 0.967 when measured at 20/20°C, or between 0.960 and 0.964 when measured at 25/25°C.
⚡ How tight is the distillation range requirement?
The standard requires a very tight distillation window of only 3 °C. The initial boiling point must be no lower than 123 °C and the dry point must be no higher than 126 °C, as determined by Test Method D1078.
📌 What methods are used to test acidity and water content?
Acidity is tested using Test Method D1613, with a maximum limit of 0.01% as acetic acid (0.093 mg KOH/g). Water content is tested using the Karl Fischer method (Test Method D1364, now withdrawn), with a maximum limit of 0.2 weight percent. Alternative validated methods may be necessary for water determination.