GB/T 46020.1-2025Plastics — Guide of design for recycling — Part 1: Poly(ethylene terephthalate) (PET) materials (English PDF)

3.23 polyolefin pump/dispenser

A pump/dispenser that contains no metal or inorganic non-metallic material and is mainly made from materials such as polypropylene (PP), high-density polyethylene (PE-HD), low-density polyethylene (PELD), and polyethylene (PE) copolymers.

4.1 Symbols

The following symbols apply to this document.

a* value Parameter in a colorimeter representing the variation of an object's color from red to green b* value Parameter in a colorimeter representing the variation of an object's color from yellow to blue L* value Parameter in a colorimeter representing the lightness of an object

4.2 Abbreviated terms

For the purposes of this document, the terms and definitions given in GB/T 1844 (all parts), as well as the following, apply.

PA MXD6.Poly(meta-xylylene diamine)

6.3 An important basis for assessing the recyclability of PET products is the

performance requirements of the intended applications for recycled PET. Downstream applications of recycled PET include container packaging, chemical fibers, sheets, and strapping. PET container packaging should preferably be designed so that, after recycling, it can be reused for its original application.

6.4 When PET products contain multiple non-PET materials or other contaminants, the

design should take into account the ease of separation during post-consumer recycling.

Density sorting is the preferred method for separating non-PET materials or other contaminants from PET, followed by color sorting or material sorting to remove non- target materials.

6.5 As PET thermoformed products differ from PET bottles in both product

characteristics and recycling processes, the factors to be considered in their design should be selected according to the specific characteristics of the products.

6.6 The recyclability of a PET product is determined by the impact of each of its design elements on the recycling process. Any design element that adversely affects recycling will reduce the overall recyclability of the product.

7.1 Base resin

7.1.1 The base resin should preferably be a general-purpose PET bottle resin. The

properties of PET resin should meet the requirements of GB/T 17931, and the properties of recycled PET resin should meet the requirements of GB/T 40006.9.The intrinsic viscosity, melting point, and monomer content of terephthalic acid and ethylene glycol in the base resin of PET products are all important factors to consider. It is advisable to select PET resin with an intrinsic viscosity >=0.72 dL/g, a melting point of 235°C~255°C, and a total content of terephthalic acid monomer and ethylene glycol monomer greater than 95% of the total monomer mass.

Note. The melting point is the result of a nitrogen gas test.

7.1.2 Post-consumer recycled PET (mechanical recycling, physical recycling, chemical

recycling) and bio-based PET are both suitable as base resins, and their properties are described in 7.1.1.

7.1.3 PET homologous resins, modified PET products, and mixtures with other resins

should be subjected to the tests required for assessing PET recyclability to determine their compatibility with PET recycling systems.

7.1.4 The classification of design for recycling of base resins is shown in Table 1.

Table 1 – Classification of design for recycling of base resins

7.2 Barrier materials and additives

7.2.1 Barrier materials are often added to PET packaging containers to protect the

contents. The forms of barrier materials include coatings, barrier layers and additives.

The addition of different barrier materials has different effects on PET recycling, such as compatibility with PET recycling streams, color value and performance of recycled PET, etc. Therefore, it is crucial to determine the impact of barrier materials on PET recycling through experimental testing.

7.2.2 Barrier materials should not be added to colorless and transparent bottles. If it is necessary to add them, relevant tests should be conducted. For the use of barrier materials that affect the color value of recycled PET, it is advisable to declare or label information about the presence of barrier materials. The color of the barrier layer should match the color of the product's appearance.

Note. Information declared or labeled on a product includes text, symbols, colors, etc. ......