ASTM D5511 Testing

What is ASTM D5511?

ASTM D5511 is a standardized test method developed by the American Society for Testing and Materials (ASTM) for determining the biodegradation rate of plastic materials under high-solids anaerobic digestion conditions. This test simulates the environment found in biologically active landfills where oxygen is limited or absent.

Test Methodology

The ASTM D5511 test involves the following steps:

1. Sample Preparation: Plastic materials are reduced to small pieces to increase surface area.
2. Inoculation: The samples are mixed with anaerobic digestate from municipal waste or wastewater treatment facilities, which contains naturally occurring microorganisms.
3. Incubation: The mixture is placed in sealed reactors and maintained at a temperature of 37 °C (mesophilic conditions) or 52 °C (thermophilic conditions).
4. Gas Measurement: The biogas (primarily methane and carbon dioxide) produced during biodegradation is collected and measured over time.
5. Data Analysis: The volume of biogas produced is used to calculate the percentage of biodegradation based on the theoretical maximum gas production.

PlastScience Performance

PlastScience additives have undergone rigorous testing using the ASTM D5511 protocol. Our bacterial nutrient-based additives have demonstrated significant biodegradation rates in anaerobic conditions, outperforming conventional plastics without additives.

Limitations of ASTM D5511

While the ASTM D5511 test is valuable for determining anaerobic biodegradation potential, it's important to understand its limitations:

• The test is conducted under optimized laboratory conditions that may differ from actual landfill environments.
• Modern landfills are designed to minimize biodegradation, so actual biodegradation rates may vary.
• The test duration (typically less than 365 days) may not capture the full biodegradation timeline.
• Results cannot be directly extrapolated to predict biodegradation in other environments, such as soil or marine conditions.

Comprehensive Testing Approach

At PlastScience, we believe in a comprehensive approach to biodegradation testing. While ASTM D5511 provides valuable data on anaerobic biodegradation, we also conduct testing using other standardized methods including:

• ISO 14855 - Aerobic biodegradation under controlled composting conditions

This multi-method approach helps us develop a complete understanding of how our additives perform across different environmental conditions and disposal scenarios.