Plastic knowledge: what are the categories of plastic films?

There are quite a few kinds of plastic film. From different angles, there are different classification methods for plastic film.

If according to plastic film processing with resin material classification, can be divided into plastic film of polyethylene, polypropylene, PVC, nylon, polyester, polycarbonate and polyimide films such as dozens of categories.

If in accordance with the processing methods of film classification, usually can be divided into calendering film, blown film, T die squeeze film, cast film, mountain dispersion casting film. If the tensile orientation is taken into account, the plastic film can be divided into non stretched, unidirectional and biaxially oriented films.

From the angle of thin plastic Teng Lai, can be divided into agricultural film, packaging film and industrial film three categories.

Because some film has some special functions, and thus people can be divided into heat shrinkable film, light (or biological) degradable film and conductive film.

The classification method of described above, is actually based on people's experience and habit formation. Strictly speaking, such a classification is not detailed enough. Some of the above classification classification category, also can be decomposed into some categories, such as polyethylene film can be subdivided into high density polyethylene film; low density polyethylene and linear low density polyethylene film. If we take into account the usual concepts of general plastics and engineering plastics, there will be a new classification, but very few of them are classified. Because of the engineering material for the main characteristics of thin films, the high temperature resistance, good mechanical properties, so in this book this kind of plastic film (such as PC, PI etc.), called high performance films.

In practice, people often from different angles to some two methods of classification methods used in combination, such as people have been very angry with BOPP (BI Xi, poly propylene membrane stretched out Apple) the word is the raw material and molding method of combining; combination of rigid PVC packaging film is raw material and use the examples like this a lot. The advantage of this classification is that it enables people to make films. Materials, properties and uses are clear.