GB/T 12670-2008Polypropylene (PP) resin (English PDF)

1 Scope

GB/T 12670-2008 is the Chinese national standard on polypropylene (pp) resin, in the field of rubber and plastic industries. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 26 February 2008 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 August 2008. Classification: ICS 83.080.20, CCS G32. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This Standard stipulates the classification, naming, requirements, test methods, inspection rules, marking, packaging, transportation and storage of polypropylene (PP) resin. This Standard is applicable to additive-containing granular propylene homopolymer (PP-H), propylene impact copolymer (PP-B) or propylene random copolymer (PP-R) prepared by the polymerization of propylene or propylene and ethylene under the effect of catalyst. This Standard is inapplicable to coloring, filling, reinforcement and blending of polypropylene resin and masterbatch material.

2 Normative References

Through the reference in this Standard, clauses of the following documents become clauses of this Standard. In terms of references with a specific date, all the subsequent modification sheets (excluding the corrected content) or the revised editions are inapplicable to this Standard. However, all parties that reach an agreement in accordance with this Standard are encouraged to explore the possibility of adopting the latest version of these documents. In terms of references without a specific date, the latest version is applicable to this Standard.

GB/T 1040.2-2006 Plastics - Determination of Tensile Properties - Part 2: Test Conditions for Molding and Extrusion Plastics ( ISO 527-2:1993, IDT)

GB/T 1250-1989 Rules for Expression and Judgement of Limiting Values

GB/T 1634.2-2004 Plastics - Determination of Temperature of Deflection under Load - Part 2: Plastics, Ebonite and Long-fiber-reinforced Composites ( ISO 75-2:2003, IDT)

GB/T 2410-1980 Determination of the Luminous Transmittance and Haze of Transparent Plastics

GB/T 2412-1980 Polypropylene - Method of Determination of Normal Indices

GB/T 2546.1-2006 Plastics - Polypropylene (PP) Molding and Extrusion Materials - Part 1: Designation System and Basis for Specifications ( ISO 1873-1:1995, MOD)

GB/T 2546.2-2003 Plastics - Polypropylene (PP) Molding and Extrusion Materials - Part 2: Preparation of Test Specimens and Determination of Properties ( ISO 1873- 2:1997, MOD)

GB/T 2547-1981 Plastic Resins; Sampling

GB/T 2918-1998 Plastics - Standard Atmospheres for Conditioning and Testing (idt ISO 291:1997)

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)

GB/T 6595-1986 Test Method for Fish Eye Count of Polypropylene Resin

GB/T 9341-2000 Plastics - Determination of Flexural Properties (idt ISO 178:1993)

GB/T 9342-1988 Plastics - Determination of Hardness by the Ball Indentation Method (eqv ISO 2039-2:1981)

3 Classification and Naming

The classification and naming of polypropylene resin shall comply with the stipulations in GB/T 2546.1-2006. For the purpose of naming, each designation of polypropylene resin shall have a nominal value of tensile elastic modulus and Charpy impact strength of simply supported beam.

6.2.2 Preparation of compression molding test piece The preparation of polypropylene resin compression molding test piece is shown in the stipulations in

3.3 in GB/T 2546.2-2003, for example, compression molding test piece for the determination of electrical performance.

6 Test Methods...

7 Inspection Rules

7.1 Inspection Classification and Items The following inspection items merely need to be inspected when determining the designation of polypropylene resin products:

---Sanitary requirements in Chapter 4;

---Molding shrinkage rate of injection molding-type polypropylene resin;

---Except from fiber-type polypropylene resin, tensile elastic modulus of other types of polypropylene resin;

---Charpy impact strength of simply supported beam (23 °C) of narrowband-type, fiber-type and thin film-type polypropylene resin. Except from the above-mentioned items, the inspection of polypropylene resin products may be divided into two types: type inspection and exit-factory inspection. All the items in Chapter 5 are type inspection items. Items that shall at least be included in the exit-factory inspection of the various types of polypropylene resin are shown in Table 6. stipulations in GB/T 2547-1981.

8 Marking

On the external packaging of polypropylene resin products, there shall be obvious marking. The content of the marking may include: trademark, manufacturer's name, serial number of standard, product name, designation, date of production, lot number and net weight, etc.

9 Packaging, Transportation and Storage

9.1 Packaging Polypropylene resin may adopt polypropylene woven bag lined with polyethylene film bag, or, other packaging forms. The packaging materials shall ensure that products are not contaminated or leaked during the transportation, stacking and storage. The net weight of each bag of product may be 25 kg, or others.