Technology and Manufacturing

c Expand All C Collapse All

There are 2 main types of biodegradable plastics: oxo-biodegradable and hydro-biodegradable. Both first undergo chemical degradation, the former by oxidation and the latter by hydrolysis, resulting in physical disintegration of the plastics and a drastic reduction in molecular weights. In both cases, biodegradation follows with the same end result – conversion into carbon dioxide, water and biomass.

In terms of differences, hydro-biodegradable plastics degrade and biodegrade more rapidly, and tend to have much shorter lifespans than oxo-biodegradable plastics. In contrast, oxo-biodegradable plastics are less expensive, possess better mechanical properties and are easier to process and manufacture (as they can be incorporated into standard manufacturing processes without the need for specific manufacturing equipment).

Oxo-biodegradable plastics are conventional plastics, primarily polyethylene or polypropylene, which are capable of oxo-biodegradation, due to the presence of a pro-degradant additive such as TDPA™.

TDPA™ acts as a catalyst for the initial, oxidative degradation phase of the breakdown of oxo-biodegradable plastics. Oxidative degradation is dependent on the presence of oxygen, and this process is further accelerated by factors such as heat, UV light, mechanical stress. Following oxidative degradation, oxo-biodegradable plastics can subsequently undergo biodegradation into carbon dioxide, water and biomass.

The product life of TDPA™ oxo-biodegradable plastics can be customized to meet your specific product requirements, taking into consideration processing conditions and product applications. We also offer bespoke, all-in-one additive masterbatches that confer multiple beneficial properties by the addition of a single masterbatch.

TDPA™ oxo-biodegradable plastics are typically designed to have a product life of 12 to 36 months.

TDPA™ plastics are oxo-biodegradable, with a customisable product life, during which they exhibit comparable physical and mechanical properties (e.g. appearance, strength, flexibility etc) to conventional plastics. At the end of its product life, TDPA™ plastic will degrade and biodegrade if it escapes into the open environment, whereas conventional plastics demonstrate minimal degradation under similar conditions.

TDPA™ is cost effective because it typically requires a low addition rate (1-2%) to make a plastic product oxo-biodegradable. In addition, it can be integrated into routine manufacturing, without a need for special equipment or additional processing steps.

  1. Controlled Lifespan: Product life (i.e shelf & service life) customizable from months to years according to application
  2. Retained Physical Properties: Comparable physical and mechanical properties as conventional plastics during lifespan
  3. Degradable: Ultimately biodegrades in the open environment to carbon dioxide, water and biomass, thereby returning to nature
  4. Ease of Manufacture: Integrated into routine manufacturing using the same machinery and equipment as conventional plastics.
  5. Cost Effective: Low addition rates (e.g. typically 1-2%), with no requirement for specific machinery or processing
  6. Food Contact:  Compliant with FDA (USA) & EFSA (EU) requirements for direct food contact applications
  7. Non-ecotoxic: Passes all ecotoxicity tests, including seed germination, plant growth and organism survival, in accordance with OECD standards
  8. Recyclable:  Recyclable, without requiring segregation from regular plastics, in conventional recycling streams
  9. Standards: Tested in accordance with international standards, ASTM D6954 (USA) & BS 8472 (UK)
  10. Scientifically-Proven: TDPA™ technology has been rigorously and independently validated by third-party laboratories for over 20 years

TDPA™ plastics are recyclable in conventional recycling streams, without needing segregation from conventional plastics. Independent scientific analysis commissioned by the Centre de recherche industrielle du Québec (CRIQ, a government agency of the Province of Quebec, Canada) concluded that TDPA™ plastics are compatible with conventional plastic recycling streams, at mixture levels of up to 50%. The physical properties and performance of both relatively thick moulded samples and blown films produced from recycling a mixture of TDPA™ and conventional plastics were comparable to those produced from recycling only conventional plastics.

In the open environment, TDPA™ plastics undergo oxidative degradation (whereby high molecular weight polymers are broken into shorter chains), followed by biodegradation (where micro-organisms consume and bio-assimilate the short chains produced by the initial oxidative degradation). TDPA™ acts as a catalyst for oxidative degradation, thereby driving degradation and biodegradation of plastic products.

Upon completion of biodegradation, TDPA™ plastics are bio-assimilated into biomass, leaving no trace of micro-plastics or other harmful residues in the environment. Thus, TDPA™ plastics do not fragment, but instead biodegrade in the open environment.

Oxo-degradation is defined by the European Committee for Standardization (CEN) in TR15351 as “degradation identified as resulting from oxidative cleavage of macromolecules”. In contrast, CEN defines oxo-biodegradation as “degradation resulting from oxidative and cell-mediated phenomena, either simultaneously or successively”.

The crucial difference, therefore, is that oxo-biodegradation features an additional biodegradation phase, which results in micro-organisms consuming the short plastic fragments (that result from initial oxidative degradation). Consequently, in the open environment oxo-biodegradable plastics, such as TDPA™ plastics, can break down into carbon dioxide, water and biomass, without causing the accumulation of micro-plastics (fragments).