The characteristic of degradable polyethylene film is that it can automatically degrade and break into small pieces after the effective use period of the film. Even if the degraded fragments remain in the soil, they will not affect the growth of crop seedlings, root development, or hinder the capillary action of the soil. It can be seen that the degradation film reduces the adverse effects on soil and environmental pollution.
The process conditions and equipment used for extrusion blow molding of degradable films are exactly the same as those for ordinary polyethylene film molding. The only difference between the two films is the formula of the raw materials used. The main raw material for the formation of degradable polyethylene film is low-density polyethylene, with a melt flow rate MFR value in the range of 4-7g/10min. A certain proportion of linear low-density polyethylene (LLDPE) can also be mixed in LDPE resin. The strength of the plastic film formed by this mixture can be increased, while the thickness of the film can be reduced. In order to achieve the degradation and fragmentation of the plastic film after its effective use period, a certain proportion of auxiliary materials that can promote product degradation should also be added to the raw materials. This is where the degradation film is different from ordinary polyethylene film.
At present, the use of HDPE as the main raw material and the use of degradable films for extrusion blown shopping bags have also begun to be widely applied.
