Preparation technology of PET/PETG shrink film

Abstract

The invention discloses a preparation technology of a PET / PETG shrink film, comprising: 1. drying treatment: drying copolyester slices at the temperature of 65-75 DEG C; 2. melt extrusion: mixing the dried copolyester with functional master batch / functional accessory ingredient, and adding into a single screw extruder to carry out melt extrusion; 3. die head / casting strip quenching: after a melt extruded fusant enters a hanger-type die head by a fusant metering pump, a filter and a fusant pipeline, casting to a cooler drum via a die lip mouth to form the casting strip; 4. unilateral stretching: stretching the casting strip processed in the last step; and 5. rolling and slitting: measuring the thickness of the unilateral stretched film on line, dragging, and rolling; and finally, slitting, checking and packaging to obtain the film product. The product produced by the method has high transparency, good mechanical behavior, high output, high cooling speed and high production efficiency, and the tolerance of the thickness thereof is smaller than that of a blown film.

Description

technical field [0001] The invention relates to a preparation process of PET / PETG shrink film. Background technique [0002] In recent years, heat shrinkable packaging films have developed rapidly, and are expanding from a single PVC shrink film to PETG, PE, PP, PVDC and other varieties of films. The market demand is constantly changing, and heat shrinkable films are moving towards multi-layer and functional directions. With the development, many new technologies and new products have appeared. In addition to being widely used in fast food pasta, ceramic products, tea sets, and mechanical parts, the combination of heat shrinkable film and vapor phase antirust technology in the application of military machinery and hardware tools , instead of the method of pouring anti-rust oil, has been widely used. [0003] At present, there are two general methods of film forming: calendering and tape casting: ①The calendering method uses various mixing machines (such as high-speed mixers...

AI Technical Summary

Problems solved by technology

The films produced by the above two methods exist respectively: the mechanical strength of the film obtained by calendering is not high, and the power consumption of the finished product is too large; the film obtained by casting has low production efficiency and low film strength. Due to the use of solvents, The solvent recovery system is added, and the unit consumption of raw materials is high.