1 Petroleum-based plastics: PET, PP and PE

PET, PP and PE are not biodegradable materials. Even if they are food-safe and non-toxic, they will take hundreds of years to decompose in natural landfills. Recycling becomes the core eco-friendly solution for these materials and is strongly encouraged by global policies.

Key environmental requirements:

• Raw material compliance: Food-grade raw materials must meet global food contact standards, with no harmful additives or heavy metal leaching.
• Design for recyclability: Simplify product structures and avoid multi-material composite designs to facilitate sorting and recycling.
• Regulated recycled materials: When recycled PET or PP is used in production, impurities and odors need strict control to meet food-contact grades.

Limitations: Even 100% recycled plastics will suffer performance degradation after multiple regranulation cycles and cannot be recycled infinitely. Improper disposal will still cause white pollution.

1.2 PLA and corn starch-based biodegradable materials

Many manufacturers misunderstand biodegradable materials and assume they can break down anywhere after disposal. In fact, the environmental value of biopolymers heavily relies on end waste treatment infrastructure.

Key environmental requirements:

• Biodegradation certification: Export products need industrial composting certificates to prove full decomposition within a specified time under industrial composting conditions without microplastic residues.
• Sustainable raw material sourcing: PLA and corn starch materials prefer raw materials grown sustainably, avoiding competition with food crops.
• Additive control: Plasticizers and modifiers used must be non-toxic and environmentally friendly.

Limitations: PLA and corn starch products barely degrade rapidly in ordinary landfills or marine environments. If mixed with conventional plastic waste, biodegradable scraps will contaminate recycled plastic streams and reduce the quality of recyclates. Therefore, biodegradable packaging requires separate industrial compost waste collection systems.

2. Environmental Requirements for Extrusion and Thermoforming Processes

Selecting eco-friendly materials is only the first step. Energy consumption, waste management and volatile emission control during manufacturing are also critical environmental audit factors and key considerations for equipment selection.

2.1 Eco-friendly points for sheet extrusion

Sheet extrusion is the first production stage, and environmental concerns mainly focus on energy usage and scrap handling:

• Energy saving: Heating and driving systems of extruders need to cut power consumption per unit output. Older equipment wastes large amounts of heat. Modern extruders adopt segmented precise temperature control to reduce heat loss and carbon emissions.
• On-site scrap recycling: Trimmings and leftover sheets produced during extrusion can be crushed and re-mixed to reduce raw material waste. Production lines for PET, PP and PLA sheets should support scrap recycling. Note that repeated recycling accelerates PLA brittleness, so the re-addition ratio must be strictly controlled.
• Volatile emission management: At high processing temperatures, plastic additives may release volatile substances. Production lines should be equipped with exhaust purification systems to meet workshop emission standards.