Clear all your doubts about polypropylene (PP) and polyethylene (PE) plastic and find out what the big difference is between these thermoplastics.
There are many plastic polymers available on the market. There are several names, acronyms, characteristics and indications. Precisely because there is such a wide variety, they also bring many questions. But it is essential that companies that work with these materials know how to differentiate them and know the specifics of each one of them.
It is precisely to help you in this task that we are going to talk about polypropylene and polyethylene plastic. A very common part of our daily lives, PP and PE are obtained from the polymerization of propene and ethylene gas. And precisely because they are synthetic polymers derived from petroleum, these two plastics have somewhat similar properties. However, their differences can also be decisive when choosing which is the best option for your product.
Before talking specifically about the differences between polypropylene and polyethylene plastic, it is important to bring a definition of each of these materials. Polypropylene, also known as PP, is a plastic derived from propylene or propylene. A thermoplastic, it can be modified when subjected to high temperatures, and its melting point is 171ºC.
Polyethylene, known by the acronym PE, is also a thermoplastic. But, its melting point is lower than the other, between 110ºC and 115ºC. With many applications in the plastic industry, it is one of the most used materials today and can be found in 5 variations. Those are:
Despite being quite similar, polypropylene and polyethylene plastics have some specific characteristics that make them more or less suitable for certain uses.
Among the main characteristics of polypropylene are:
In general, polyethylene is an economical, versatile, flexible, and easy-to-process thermoplastic. But when we talk about its specificities, we must remember that its particularities can change according to the variation of the PE.
LDPE, for example, is low density. This means that it allows the application of thinner and more flexible plastics. In addition, among its main features, the following stand out:
HDPE, on the other hand, has a higher crystallinity than LDPE, ensuring its fusion at higher temperatures. With this, it can be more transparent than the previous one and also more resistant to heat. However, it is less flexible. In addition to these features, we can highlight:
As you can see, polypropylene and polyethylene plastic are very similar. But, they have two big differences: resistance and transparency. In short:
Polypropylene is more transparent and less resistant to sub-zero temperatures, and can even break. Polyethylene, on the other hand, can be subjected to low temperatures without being altered, but its transparency is not as good as PP.
It is for these reasons, for example, that polyethylene is the most suitable for use in packaging materials that need to be frozen. Polypropylene, on the other hand, is the material used to manufacture packaging that is intended to keep the product apparent.
As we said earlier, it is the characteristics of these thermoplastics that define their usability. And although both are extremely versatile, there are some functions that are better suited for them.
Regarding polypropylene, we can highlight:
Polyethylene is widely used in:
Now that you know the differences and the main characteristics of polypropylene and polyethylene plastic, get to know Lamiex products. Specialists in PP and PE laminate sheets, we serve from the food sector, to mining, water treatment, automotive and much more.
Check the Lamiex product catalog.