Characteristics and applications of PP and PA films

Biaxially oriented polypropylene film (BOPP)

PP film takes biaxially oriented polypropylene film as an example. BOPP is made by co-extrusion of polypropylene particles to form a sheet, and then stretched in both vertical and horizontal directions.

BOPP characteristics:

Due to the orientation of the stretched molecules, the film has good physical stability, mechanical strength, air tightness, high transparency and gloss, toughness and wear resistance. After being compounded with polyethylene film, it has moisture resistance, transparency, strength, and stiffness. Degree and printability are ideal;

BOPP application:

At present, the most widely used printing film is generally used with a thickness of 20-40μm, and the most widely used is 20μm. The main disadvantage of biaxially oriented polypropylene film is poor heat sealability, so it is generally used as the outer film of composite film, suitable for dressing Dry food.

Because the surface of the biaxially oriented polypropylene film is non-polar, the crystallinity is high, and the surface free energy is low. Therefore, its printing performance is poor, and its adhesion to ink and adhesive is poor. It needs to be surfaced before printing and lamination. deal with.

Nylon film (PA)

PA film characteristics:

Nylon film is a very tough film with good transparency, good gloss, high tensile strength, high tensile strength, and good heat resistance, cold resistance, oil resistance and organic solvent resistance. It has excellent abrasion resistance and puncture resistance, and is relatively soft, and has excellent oxygen barrier properties, but has poor water vapor barrier properties, high moisture absorption and moisture permeability, and poor heat sealability.

PA film application:

Suitable for packaging hard items, such as greasy foods, meat products, fried foods, vacuum packaged foods, steamed foods, etc.