The Role Of PTFE Powder In Polypropylene Foaming Materials

The role of PTFE powder in polypropylene foaming materials. All thermosetting and thermoplastic plastics can be made into foaming plastics. Common foaming plastics include polystyrene, polyurethane, polyolefins, etc.

The application of foamed polypropylene materials in the automotive industry has been expanding in recent years, which can greatly reduce the weight of automobiles and save fuel consumption.

Polypropylene (PP) microporous foaming materials have the advantages of excellent comprehensive mechanical properties, stable chemical properties, high heat resistance, good low temperature properties, environmental friendliness, good sound insulation and sound absorption properties, and surface protection properties. They are widely used in electronic material packaging, construction, and transportation vehicles.

However, conventional polypropylene has low melt strength and a very narrow foaming temperature window (4°C), which makes it difficult to achieve continuous industrial production in the supercritical carbon dioxide foaming process. In addition, the nucleation density of polypropylene is low, the pore size distribution of the foaming material is uneven, and the pore density is low, which brings great restrictions on the performance required for practical applications. Therefore, the development of high-strength polypropylene foam materials with excellent comprehensive performance is one of the focuses of research and industrial technology development, and it is necessary to develop low-cost and easy-to-implement polypropylene foaming material processes.

The role of PTFE powder in polypropylene foaming materials:

1. PTFE powder particles with nano-microporous structure are blended and modified with PP to improve the supercritical carbon dioxide foaming of PP. After the PTFE powder particles are fully swollen in high-pressure CO2 and then the pressure is suddenly released, they will split into multiple nanoparticles to achieve the effect of highly efficient enhanced heterogeneous nucleation. This method is used to prepare PP foaming materials with ultra-high pore density and controllable void density.

2. The pore density can be regulated (109~1011cells/cm3) by simply controlling the amount of PTFE powder added; and the micropore morphology of PP foam is regular, the pores are mostly polygonal structures, and the continuity between the pores is good.