GB/T 20197-2006Define, classify, marking and degradability requirement of degradable plastic (English PDF)

3.1 Degradation

A process that it is affected by environmental conditions after a certain time and contains one or more steps, through which the structure is changed significantly and loss of properties (such as integrity, relative molecular mass, structural or mechanical strength). Refer to deterioration (3.6).

3.4 Ultimate anaerobic biodegradation

Under hypoxic conditions, the material is eventually decomposed by microorganisms to carbon dioxide (CO2), methane (CH4), water (H2O), mineralized salts with the elements, and new biomass.

3.5 Biological treatability

Potential compostability of the material under aerobic conditions OR potential biological digestion ability of the material under anaerobic conditions.

3.6 Deterioration

Plastic's permanent changes of loss of physical properties due to some structural damages.

4.1 Classification

Degradable plastic includes biodegradable plastic, compostable plastic, photo-degradable plastic sheet and heat- and/or oxide-degradable plastic, according to its designed final degradation mode.

4.2 Marking

The marking for degradable plastic is as follows. Example: […]

4.3 Product material marking method

Marks for degradable plastic products shall be on products or on the outer package according to the provisions in 4.2.

4.3.2 Multi-constituent product

Multi-constituent products of polymers, mixture or alloy shall be arrayed in accordance with the mass percentage of main constituents of each kind, in large-small descending order. It shall use abbreviation to represent the polymers' constituents, and separate the abbreviations with "+", according to the provisions of 4.2.

4.3.3 Additive-containing products (optional)

4.4 Marks making

Marks shall be made by molding, printing, embossing, branding or other clear marking methods that cannot be erased.

5.1 Biodegradable plastic

5.1.1 Single polymer

If the material is processed and made by single polymer, then the biodegradation rate shall be >=60%; test method is shown in 6.1.

5.2 Compostable plastic

5.2.1 Single polymer

If the material is processed and made by single polymer, then the biodegradation rate of compost shall be >=60%, the degree of disintegration shall be >=90%. The test method is shown in 6.2.1.

5.2.3 Compost quality

Compost quality shall comply with quality standard for compost products in CJ/T 3059 (shown in Table 2). The test method is shown in 6.2.2.

5.3 Photo-degradable plastic sheet

Photo-degradation exposure mode of photo-degradable plastic sheet shall use natural solarization or solarization by Xenon lamp in artificial accelerated aging box. Photo-degradability shall comply with the provisions in Table 3. The test method is shown in 6.3.

6.1 Biodegradability

Biodegradation test shall be conducted according to GB/T 19277 and/or GB/T 19276.1 and/or GB/T 19276.2 and/or ISO 17556:2003 or ISO 14853:2005 or ISO 15985:2004.The test result shall be represented by the maximum biodegradable percentage.

6.2 Compostable property

6.3 Photo-degradation test

6.3.1 Exposure conditions

Exposure mode of photo-degradation shall use natural solarization or solarization by Xenon lamp in artificial accelerated aging box. The specific solarization mode and conditions shall comply with the provisions in Table 5.

6.3.2 Retention rate of tensile elongation at break

6.3.2.1 Tensile elongation at break

When sample thickness is less than 1 mm, conduct the test according to the provisions in GB/T 13022. Use type-I sample; take 5 samples. The test results shall be respectively represented by the arithmetic average of determination results. Tensile speed is (50±5) mm/min.

6.3.3 Mass decrease rate of weight average relative molecular mass

Weight average relative molecular mass before and after photo-degradation of sample by high temperature gel chromatograph, and relative molecular mass separation range limit of gel material for relative molecular mass test shall include relative molecular mass that is less than 5000.

6.4 Heat- and/ or oxide-degradation

Heat- and/ or oxide-degradation test shall be conducted according to ASTM D5510:1994 (2001). […]