EVOH cast film
DATE：2019/6/25 10:02:40 / READ： / SOURCE：This station
EVOH cast film
The EVOH film production process equipment is relatively simple, the equipment investment is relatively small, the film thickness is usually about 20um, and the process is relatively mature. As mentioned above, the product is generally not suitable for use alone, and can only be used as a barrier layer for the high barrier multilayer film.
Compared with PP and PE, the EVOH cast film molding conditions control the moisture and molding temperature of the resin.
EVOH resin is easy to absorb moisture and needs to be dried before molding. It is usually pre-dried at 100-110 °C for 2~3h in a drying oven or hot air circulation dryer.
If the EVOH resin is retained in the extruder for a long time, the resin changes with time and gelation occurs. Therefore, before the molding is finished, a small amount of lubricant should be added to the extruder, and the melt viscosity is added. High polyolefin, the EVOH resin in the extruder is extruded for ready to be turned on again.
3. Biaxial stretching process to produce EVOH film
The process is complicated, the equipment investment is high, and the film thickness is above 10um. Under the same mechanical properties, the biaxially stretched film has higher strength than the cast film, and is generally not used alone, and is mainly used for high barrier multilayer composite materials. Barrier layer.
The single-layer EVOH film has poor heat sealability and is heat-sealed after secondary processing.
4. Co-extruded EVOH composite film
The EVOH co-extrusion line has a co-extrusion casting method and a co-extrusion blow molding method. The co-extrusion casting method is produced in three countries abroad, Germany's Barmac, Caifen, Italy, Po'lytype, Prandi SPA, Austria. Lenzing Corporation, Davis Standards Inc. of the United States, etc. Co-extrusion blow molding machine manufacturers include Barmac, Caifen, and other extruders. The extruder is equipped with nylon and EVOH.
The screw, head connector and head of the PO are designed to be suitable for EVOH. Generally has the following characteristics:
1) Extruder: L/D=27, can process different types of polymers, there are three different types of screws, which can be matched with three groups of five-layer film production lines.
2) Blocking the main core layer: The extruder is equipped with special screws for processing nylon, EVOH and PO. All melt channels are designed and installed according to the requirements of EVOH extrusion.
3) Filter: The pipe is streamlined to avoid the deposition of impurities. Especially for heat-sensitive materials, such as EVA, nylon, and EVOH, the filter insert can be replaced without removing the parts such as the machine head.
4) Handpiece: It can provide different film components with heads, such as AB, AB+ adhesive layer, ABC, ABA, ABCD, ABCDA, ABCBD.
The EVOH film production process equipment is relatively simple, the equipment investment is relatively small, the film thickness is usually about 20um, and the process is relatively mature. As mentioned above, the product is generally not suitable for use alone, and can only be used as a barrier layer for the high barrier multilayer film.
Compared with PP and PE, the EVOH cast film molding conditions control the moisture and molding temperature of the resin.
EVOH resin is easy to absorb moisture and needs to be dried before molding. It is usually pre-dried at 100-110 °C for 2~3h in a drying oven or hot air circulation dryer.
If the EVOH resin is retained in the extruder for a long time, the resin changes with time and gelation occurs. Therefore, before the molding is finished, a small amount of lubricant should be added to the extruder, and the melt viscosity is added. High polyolefin, the EVOH resin in the extruder is extruded for ready to be turned on again.
3. Biaxial stretching process to produce EVOH film
The process is complicated, the equipment investment is high, and the film thickness is above 10um. Under the same mechanical properties, the biaxially stretched film has higher strength than the cast film, and is generally not used alone, and is mainly used for high barrier multilayer composite materials. Barrier layer.
The single-layer EVOH film has poor heat sealability and is heat-sealed after secondary processing.
4. Co-extruded EVOH composite film
The EVOH co-extrusion line has a co-extrusion casting method and a co-extrusion blow molding method. The co-extrusion casting method is produced in three countries abroad, Germany's Barmac, Caifen, Italy, Po'lytype, Prandi SPA, Austria. Lenzing Corporation, Davis Standards Inc. of the United States, etc. Co-extrusion blow molding machine manufacturers include Barmac, Caifen, and other extruders. The extruder is equipped with nylon and EVOH.
The screw, head connector and head of the PO are designed to be suitable for EVOH. Generally has the following characteristics:
1) Extruder: L/D=27, can process different types of polymers, there are three different types of screws, which can be matched with three groups of five-layer film production lines.
2) Blocking the main core layer: The extruder is equipped with special screws for processing nylon, EVOH and PO. All melt channels are designed and installed according to the requirements of EVOH extrusion.
3) Filter: The pipe is streamlined to avoid the deposition of impurities. Especially for heat-sensitive materials, such as EVA, nylon, and EVOH, the filter insert can be replaced without removing the parts such as the machine head.
4) Handpiece: It can provide different film components with heads, such as AB, AB+ adhesive layer, ABC, ABA, ABCD, ABCDA, ABCBD.
Author：admin