1.1 This standard establishes a system of designation for polystyrene thermoplastic material. This designation system may be used as the basis for specifications.
1.2 Polystyrene resins are classified, based on the following properties, appropriate levels of the basic polymer parameters, intended application and/or method of processing, important properties, additives, colorants, fillers and reinforcing materials.
a) Vicat softening temperature
b) melt flow rate
1.3 This standard is applicable to all amorphous polystyrene homopolymers, and it is applicable to materials ready for normal use, unmodified or modified by colorants, additives, fillers, etc.
This standard does not apply to expanded polystyrene, styrene copolymers, homopolymers of substituted styrene and those modified with other polymers such as elastomer.
1.4 It is not intended to imply that materials having the same designation give necessarily the same performance. This standard does not provide engineering data, performance data on processing conditions which may be required to specify a material for a particular application and/or method of processing.
If such additional properties are required, they shall be determined in accordance with the test method specified in part 2.
1.5 In order to specify a thermoplastic material for a particular application or to reproducible processing,additional requirement may be given in data block 5(see clause 3. introductory paragraph)
1.6 Appendix(designation) is applicable by March 31, 2001.
Note Dimensions and figures in of this standard follow the previous ones.