The main component of PP is polypropylene.
The main component of PE is polyethylene.
2, the performance is different
PP has good toughness, because its hard and brittle material determines that it is only suitable for packaging but not for bearing.
PE is moisture-proof, oxygen-proof, acid-resistant and alkali-resistant, with general air tightness, good ductility, not easy to be damaged and excellent heat sealing.
3. Different applications
PP can be used to make greenhouses, plastic films, culture bottles, farm tools, fishing nets, food turnover boxes, food bags, beverage packaging bottles and so on.
PE can be processed by blow molding, extrusion, injection molding and other methods, and is widely used to manufacture films, hollow products, fibers and daily necessities.
Extended data
Polypropylene (PP) is the second most common plastic in modern society. With the development of construction, automobile, household appliances and packaging industries, waste PP has become one of the waste polymer materials with large output in recent years.
The treatment methods of waste polypropylene mainly include incineration for energy supply, catalytic cracking for fuel production, direct utilization and recycling. Considering the technical feasibility, cost, energy consumption, environmental protection and other factors in the process of waste PP treatment, recycling is the most commonly used, effective and advocated waste PP treatment method.
Due to the influence of light, heat, oxygen and external force, the molecular structure of PP will change, and the product will turn yellow, brittle and even crack, which will lead to the obvious deterioration of toughness, dimensional stability, thermal oxygen stability and processability of PP, so it is difficult to meet the requirements of processing and use by directly using waste PP.
Therefore, the recycling technology of waste PP continues to develop. By alloying with other polymers or compounding with fillers, the processability, thermal properties and physical and mechanical properties of waste PP can be obviously improved, and the high performance of waste PP can be realized.