ASTM E2008-17(2021) PDF

Overview

ASTM E2008-17(2021), titled Standard Test Methods for Volatility Rate by Thermogravimetry, establishes methods for determining the volatility rates of solid and liquid materials using thermogravimetric analysis (TGA). Developed by ASTM International, this standard provides procedures to measure the rate at which substances lose mass due to vaporization at controlled temperatures under specified experimental conditions.

Thermogravimetry, or TGA, is a thermal analysis technique in which the mass of a sample is tracked over time as it is exposed to a regulated temperature program. The primary outcome of these test methods is the volatility rate, expressed as mass loss per unit time (typically µg/min), under particular conditions. The methods outlined are applicable across a temperature range from 25 °C to 500 °C, depending on the equipment in use.

Key Topics

• Volatility Rate Measurement: The standard defines volatility rate as the mass of a solid or liquid converted into vapor per unit time at a given temperature, offering a reproducible and precise way to characterize volatile behavior.
• Test Methodology: Two principal methods are described:
  • Isothermal Test (Method A): Monitors mass loss at a fixed temperature over a set time, providing an average volatility rate.
  • Constant Heating Rate Test (Method B): Measures instantaneous volatility rate as the temperature is increased at a constant rate.
• Specimen Handling: Samples are enclosed in containers with tightly controlled pinhole diameters (0.33 mm to 0.38 mm), which ensures minimized sensitivity to experimental variables like surface area or gas flow rate, making temperature the key variable.
• Precision and Index Values: The volatility rates determined serve as index values to compare materials, not absolute predictions of processing behavior. Results help rank materials for volatility under consistent laboratory conditions.

Applications

• Material Screening & Selection: Engineers and scientists use these test methods to rapidly compare and rank materials based on their volatility, supporting material selection for processes involving evaporation, drying, or volatile containment.
• Process Optimization: The volatility rate data can support estimation of drying intervals and quantify volatile release in processing environments, informing decisions in manufacturing, packaging, and storage.
• Quality Control: Manufacturers can implement these standard test methods for quality assessment, ensuring material batches meet specification for volatility during production or product development.
• Research & Development: Academics and industrial researchers utilize these standardized measurements for fundamental research, innovation in volatile material handling, and compliance with industry regulations.

Related Standards

ASTM E2008-17(2021) references several other ASTM standards which provide definitions, calibration, and measurement frameworks crucial for consistent thermogravimetric analysis:

• ASTM E177 - Precision and bias practices for test methods.
• ASTM E473 & E1142 - Terminology for thermal analysis and thermophysical properties.
• ASTM E691 - Interlaboratory studies for test method precision.
• ASTM E1582 - Temperature calibration for thermogravimetric analyzers.
• ASTM E1860 & E2040 - Calibration for elapsed time and mass scale in thermal analyzers.

For accurate implementation of thermogravimetric volatility testing, users should consider all referenced standards and maintain adherence to the latest safety and reporting practices as outlined in ASTM E2008.

Keywords: volatility rate, thermogravimetry, thermogravimetric analysis, TGA, mass loss, ASTM E2008, standard test methods, thermal analysis, material volatility, laboratory testing.