1.1 This part of GB/T 2546 establishes a system of designation for polypropylene (PP) thermoplastic material, which may be used as the basis for specifications.
1.2 The types of polypropylene thermoplastic are differentiated from each other by a classification system based on appropriate levels of the designatory properties, and on information about basic polymer parameters, intended application and/or method of processing, important properties, additives, colorants, fillers and reinforcing materials.
a) Tensile modulus of elasticity
b) Notched Charpy impact strength;
c) Melt mass-flow rate (MFR)
1.3 This part is applicable to all propylene homopolymers and to copolymers of propylene with a content of other 1-olefins of less than 50 % (m/m) as well as blends of polymers containing at least 50 % (m/m) of aforementioned polymers.
It applies to materials ready for normal use in the form of powder, granules or pellets and to materials unmodified or modified by colorants, additives, fillers, etc. This part does not apply to propylene-based rubber.
1.4 It is not intended to imply that materials having the same designation give necessarily the same perform-ance. This part does not provide engineering data, performance data or 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 methods specified in part 2 of this standard.
1.5 In order to specify a polypropylene material for a particular application or to ensure reproducible processing, additional requirements may be given in data block 5.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this part of GB/T 2546. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties who enter into agreement according to this part are encouraged to research whether the latest editions apply. For undated references, the latest editions apply.
GB/T 1844.1-1995 Symbols of Plastics and Resins - Part 1: Basic Polymers and Their Special Characteristics (neq ISO 1043-1: 1987)
GB/T 1844.2-1995 Symbols of Plastics and Resins - Part 2: Fillers and Reinforcing Materials (neq ISO 1043-2:1987)
GB/T 2546.2-2003 Plastics - Polypropylene(PP) Moulding and Extrusion Materials - Part 2: Preparation of Test Specimens and Determination of Properties (ISO 1873.2-1997, MOD)
GB/T 3682-2000 Determination of the Melt Mass-flow Rate (MFR) and the Melt Volume-flow Rate (MVR) of Thermoplastics (idt ISO 1133-1997)
3 Designation and Specification System
GB/T 2546.1-2006 The following standards are cited：
