This specification covers the classification of sulfone plastics suitable for injection molding and extrusion. It is intended to be a means of calling out sulfone plastics used in the fabrication of end items or parts. Sulfone polymers, being thermoplastic, are reprocessable and recyclable. All of the sulfone polymers which are under this specification contain ether oxygen which is a necessary component of the polymers as in the diphenyl sulfone moiety. Examples of moieties which can be part of the backbone of the repeating unit, in addition to diphenyl sulfone, are diphenyl isopropylidene, and biphenyl. Blends of these polymers can exist as well as co- and ter-polymers. Commercial polymers that are members of this class of thermoplastics include polysulfone (PSU), polyether sulfone (PESU), and polyphenylsulfone (PPSU). Unreinforced sulfone plastics are classified into groups in accordance with their composition. The classes and grades in which these groups are subdivided are shown in this specification. The plastic shall be tested for deflection temperature, Izod impact, and solution viscosity.

1.1 This classification system covers sulfone plastics suitable for injection molding and extrusion. Sulfone polymers, being thermoplastic, are reprocessable and recyclable. This classification system allows for the use of reprocessed or recycled sulfone polymer materials.

1.2 The properties included in this standard are those required to identify the compositions covered. Other requirements necessary to identify particular characteristics important to specialized applications are to be specified by using the suffixes in Section 5. See Guide D5740.

1.3 This classification system and subsequent line callout (specification) are intended to provide a means of calling out sulfone plastics used in the fabrication of end items or parts. It is not intended for the selection of materials. Material selection can be made by those having expertise in the plastics field only after careful consideration of the design and the performance required of the part, the environment to which it will be exposed, the fabrication process to be employed, the costs involved, and the inherent properties of the material other than those covered by this standard.

1.4 The following safety hazards caveat pertains only to the test method portion, Section 11, of this classification system: 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 1: Reference Guide D7209 for information and definitions related to recycled plastics.

Note 2: ISO 24025 is similar in subject matter but not equivalent to this standard.

1.5 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.