ASTM D3418-21 - 1.9.2021
 
Significance and Use

5.1?Thermal analysis provides a rapid method for measuring transitions due to morphological or chemical changes in a polymer as it is heated/cooled at a controlled rate through a specified temperature range. Change in specific heat capacity, heat flow and temperature values are determined for these transitions. Differential scanning calorimetry is used to assist in identifying specific polymers, polymer alloys, and certain polymer additives, which exhibit thermal transitions. Chemical reactions that cause or affect certain transitions have been measured with the aid of this technique; such reactions include oxidation, curing of thermosetting resins, and thermal decomposition.

5.2?This test method is useful for specification acceptance, process control, and research.

 
1. Scope

1.1?This test method covers determination of transition temperatures and enthalpies of fusion and crystallization of polymers by differential scanning calorimetry.

Note 1:?True heats of fusion are to be determined in conjunction with structure investigation, and frequently, specialized crystallization techniques are needed.

1.2?This test method is applicable to polymers in granular form or to any fabricated shape from which it is possible to cut appropriate specimens.

1.3?The normal operating temperature range is from the cryogenic region to 600?C. Certain equipment allows the temperature range to be extended.

1.4?The values stated in SI units are the standard.

Note 2:?This test method does not apply to all types of polymers as written (see 6.8).

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.

Note 3:?This standard is similar but not equivalent to ISO 11357-1, -2, -3. The ISO procedures provide additional information not supplied by this test method.

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.

 
2. Referenced Documents

E1953-20

Standard Practice for Description of Thermal Analysis and Rheology Apparatus

ISO?11357-1

Plastics--Differential Scanning Calorimetry (DSC)--Part 1: General Principles

E691-23

Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

E967-18

Standard Test Method for Temperature Calibration of Differential Scanning Calorimeters and Differential Thermal Analyzers

ISO?11357-2

Plastics--Differential Scanning Calorimetry (DSC)--Part 2: Determination of Glass Transition Temperature

E1142-23b

Standard Terminology Relating to Thermophysical Properties (Includes all amendments and changes 10/5/2023).

ISO?11357-3

Plastics--Differential Scanning Calorimetry (DSC)--Part 3: Determination of Temperature and Enthalpy of Melting and Crystallization

E473-23b

Standard Terminology Relating to Thermal Analysis and Rheology (Includes all amendments and changes 10/5/2023).

E968-02

Standard Practice for Heat Flow Calibration of Differential Scanning Calorimeters