BIODEGRADABLE POLYPROPYLENE FAQs
1. What is Compostable? Biodegradable? Oxo-Biodegradable?
• ASTM defines “Compostable” is capable of undergoing biological decomposition in a compost site as part of an available program, such that plastic is not visually distinguishable and breaks down to carbon dioxide, water, inorganic compounds, and biomass, at a rate
consistent with known compostable materials (e.g. cellulose).
• ASTM defines “Biodegradable” as capable of undergoing decomposition into carbon dioxide, methane, water, inorganic compounds or biomass in which the predominant mechanism is the enzymatic action of microorganisms that can be measured by standardized tests, in a specified period of time, reflecting the available disposal conditions.
• Oxo-Biodegradable Plastics contain a catalyst that speeds the decomposition of long molecular chains into shorter molecular chains which then can be consumed by microorganisms in a biodegradation process. Often these catalysts are salts of transition metals such as cobalt. They rely on exposure to heat above 140° F or sunlight (UV) to begin the oxidation process. Once the oxidation process starts, it cannot be stopped.
• Anaerobic refers to microorganisms that are active in the absence of free oxygen.
• Aerobic refers to microorganisms that are active only in the presence of free oxygen.
2. In what environments will our film biodegrade?
• Our films can biodegrade in both aerobic and anaerobic environments. However, the most common disposal environment for our products would be in a landfill.
3. How long does it take to biodegrade?
• ASTM D5511-02 testing is utilized to show evidence of biodegradability within a 120 day time period under controlled conditions. Biodegradation does not occur in a predictable, straight-line fashion. Rather it occurs in a series of stops and starts as various microorganisms participate in the biodegradation process. This and variability of microorganism type and quantity from landfill to landfill make it impossible to put a firm number on how long it will take to biodegrade. In general, one can safely say cast polypropylene (CPP) film with EcoPure™ should biodegrade in landfills within “years” as opposed to “100’s of years” for CPP without EcoPure™.
4. What testing has been done to prove our film is biodegradable?
• We have tested a clear 5 mil CPP film under ASTM D5511-02 conditions. The test was conducted for 90 days and the result was about 30% biodegradation of our film. Biodegradation percent is calculated per the ASTM D5511-02 method which measures the net gaseous carbon produced from a test vessel minus the net gaseous carbon from a blank vessel only containing inoculum (inoculum is derived from anaerobic digesters operating only on pretreated household waste).
5. What is ASTM D5511-02?
• ASTM D5511-02 is a test method that determines the degree and rate of anaerobic biodegradation of plastic materials in a high-solids anaerobic environment. Test materials are placed in an inoculum that is derived from anaerobic digesters operating only on pretreated household waste. Testing is conducted over a specified period of time so no estimates can be made as to when the plastic material will fully biodegrade.
6. Do we have a certificate to back it up?
• No, we do not have any certificates, but we do have valid test data from an independent laboratory that shows one of our polypropylene films produced with the EcoPure™ additive did biodegrade under ASTM D5511-02 conditions over a test period of 90 days.
7. Can we guarantee the biodegradation?
• No. We can provide data from our testing and the conditions of those tests.
8. Does this biodegradable additive affect some properties of the film?
• Based on our experience with the EcoPure™ additive, it does not have much, if any, the effect on mechanical properties such as stiffness, tear, or heat stability. We have noticed a minor impact on optical properties. Haze is increased slightly and gloss is decreased slightly on clear films. No noticeable effect has been observed on opaque products.
9. Does the additive alter the shelf life of the film?
• Films made with EcoPure™ have the same shelf life as our films without EcoPure™. The additive should not have a negative effect on the shelf life of the film.
10. Can the film be printed on?
• Yes. Corona treatment on one or both sides of the film – enabling the film to be ink receptive. EcoPure™ should not have a negative impact on the printability of our films.
11. Are any toxic materials produced when the material breaks down?
• Unlike some other technologies, there are no toxic materials produced when the film breaks down. Our film biodegrades into carbon dioxide and methane gas in a closed landfill.
12. Can the film be recycled?
• Yes, our film with EcoPure™ can be recycled under the #5 recycling code designated for polypropylene.
13. Advantages over Oxo-Biodegradable technology
• Oxo-Biodegradable films utilize catalysts containing salts of transition metals such as cobalt. Exposure to heat of 140° F or more and/or exposure to sunlight (UV) starts the oxidation process (embrittlement) and it cannot be reversed. Shelf life is unpredictable as the Oxo-Biodegradable film could be exposed to these conditions during transit, converting or on shelf conditions. EcoPure™ does not contain these types of catalysts. Biodegradation starts only when the film is safely in a landfill environment in contact with microorganisms. Therefore, incidental exposure to (UV) light (or temperatures above 140°F) will not adversely affect the shelf life of the product any more than our standard polypropylene without EcoPure™.