The Application and Feature of Plastic foaming

Interview with Mr. He Yadong, Professor and Doctoral Supervisor of Beijing University of Chemical Technology

Plastic foaming can make the material lightweight and endow the material with various powerful functions, such as thermal insulation, cushioning and energy absorption, sound absorption and noise reduction, adsorption and filtration, insulation and low dielectric, etc. Not only that, plastic foam can further play a more important role in the fields of carbon reduction, environmental protection, new energy, recycling and sustainable development.

Because of this, plastic foaming technology has received more and more attention, and even plays an irreplaceable role in many applications.

Especially in recent years, there have been some major achievement transformation projects in the domestic plastic foaming field that can generate higher economic benefits, form a supporting role for related industries, and solve the industry's "stuck neck" key technologies.

1. Application of foamed plastic

When it comes to foamed plastics, many people may first think of polyurethane (PUR) foaming materials. In addition, common foaming materials include: expanded polystyrene (EPS), polyvinyl chloride (PVC), Expanded polyethylene (EPE), expanded polypropylene (EPP), expanded PET, etc. Whether it is building insulation, cushioning packaging, furniture applications, or structural core materials in composite materials, logistics turnover boxes, seat cushions, and automotive fields, foamed plastics are widely used.

"In recent years, the research on PET foaming has been accelerating." Professor He Yadong shared, "It is a rigid foam material, which is prepared by extrusion physical foaming process, and is generally used for composite structural core materials, such as wind turbine blades, light truck compartment panels, etc., which can reduce the weight of the structure and significantly improve the structural rigidity. Because it can be prepared from recycled beverage bottles, and it can be completely recycled, it is non-toxic and pollution-free, so it has attracted widespread attention.”

2. Plastic foam, not only lightweight and high performance

In practical applications, the significance of plastic foaming technology is not only in terms of light weight and high performance.

For example, a large number of materials used for foaming can come from recycled materials. Although the foaming process has high requirements on the processing performance of materials, with the refinement of the classification and screening of recycled materials, more and more types and quantities of recycled materials will be able to meet the foaming process requirements, such as PS, PVC, PE, PET, PA, etc. are of great significance to the reuse and reduction of solid waste.

As we all know, the main plastics that cause current environmental problems come from disposable packaging materials, such as films, packaging bags, beverage bottles, cushioning packaging, etc., so biodegradable plastics have become a hot topic today. Biodegradable materials such as PLA and PBAT can be lightweighted by foaming and applied in the field of disposable packaging, which is of great help in reducing the application of non-biodegradable packaging materials.

Not to mention the wide application of plastic foam materials in the field of energy saving. PU foam, EPS foam, and XPS foam are currently the three most important types of building insulation materials, which play an important role in reducing building energy consumption and carbon emissions. In the field of automobile lightweight, the amount of PP foam and PET foam is also increasing, which further reduces fuel consumption and improves car comfort. In the field of new energy wind power generation, the structural core materials that account for more than 25% of the blade cost mainly use PVC cross-linked foam and PET foam. Due to the recyclability of PET foam, it will become the mainstream of the blade structural core material and play an important role in energy.