Biaxially oriented polypropylene film
DATE：2022/1/21 8:23:48 / READ： / SOURCE：This station
Biaxially oriented polypropylene film
1. Main raw materials
BOPP film is made of isotactic PP as the main raw material, and is made of additive masterbatch with a mass fraction of 3% to 5% according to different products and uses. The raw material should be sea film P homopolymer, and should have the following characteristics: ① melt flow rate of 1.5-4.0g/0min; ② isotacticity of 5% to 98%; ③ moisture content < 0.03%; ④ ash < 0.2×10-3. Additives are auxiliary components for film making. Generally, erucamide type lubricants, ethylenediamine type antistatic agents and antifreeze agents containing silicon oxide particles are used to improve the surface properties of products.
2. Main equipment and basic process flow
The equipment is mainly manufactured by professional companies of BOPP automatic production lines. Companies that can provide complete sets of BOPP equipment technology include: Japan's Mitsubishi Heavy (MT-SUBISHI) and Toshiba (TOSHIBA); France's CELLIER; )Wait. Among these competitive technologies, the technologies of Mitsubishi Heavy Industries and Bruckner are more advanced. The technology of Mitsubishi Heavy Industries is characterized by Shenlian twin-screw extrusion and multi-roll cooling molding; Brückner is famous for its multi-machine co-extrusion, double-cylinder filter large-roll water bath chilling, and rational use of additives. The twin-screw joint extrusion of Mitsubishi Heavy Industries has good plasticization, uniform and stable pressure, small lateral shrinkage of thick sheets, and good thick sheet tolerances, but the multi-roll cooling process conditions are narrow, cooling is slow, and large-scale high-speed production is limited. Brückner's multi-machine co-extrusion, using different extruder combinations and matching die heads, can produce light films and multi-layer films; using double-cylinder filter devices, filters can be replaced during production; large rollers are used for internal cooling In addition to adding water to dissolve, the molten material can quickly pass through the crystallization temperature zone and be quenched to room temperature, which is conducive to high-speed large-scale production; using additives to adjust the formula, the product has large variability and good film performance.
3. The production of BOPP film is carried out according to the following basic process
PP→extrusion→filtering→die head forming→quick cooling casting→thick sheet thickness measurement→longitudinal stretching→horizontal stretching→edge trimming→film thickness measurement→corona treatment→winding and aging treatment→slitting and packaging.
Author：admin