Prior to this time, plasticizers were mainly phthalate products. However, with the gradual widespread application of DOP in the food and pharmaceutical industries, it was found that plasticizers had the risk of precipitation. Especially in the field of wires and cables in PVC soft products, traditional liquid plasticizers had the tendency of precipitation, such as the mechanical properties and electrical properties of PVC cables. Therefore, it is necessary to reduce the amount of liquid plasticizer to reduce the risk of precipitation. However, the reduction of plasticizer dosage will inevitably bring other problems, such as material hardness, low temperature performance, tensile strength agent elongation at break, etc., so solid plasticizer came into being
Plasticizers are mainly used in PVC soft products and PVC semi hard products. They are usually used together with liquid plasticizers. Solid plasticizers in the standard formula 1-3 can significantly improve the precipitation of PVC products.
Reasons and adjustment methods for PVC extrusion products precipitation:
1. When PVC processing aids exist, the melt pressure is high and the material is "over plasticized". First, consider reducing the amount of processing aids, reducing the set temperature or extrusion speed, and then consider whether to increase lubricant or PVC heat stabilizer according to the adjustment effect.
2. Under the condition of PVC smoothing agent, when the melt pressure is low and the material plasticization is not good, it should consider reducing the amount of PVC lubricant, increasing the set temperature or extrusion speed, and then consider whether it can be increased according to the adjustment effect.
3. Raise the barrel temperature.
The advantages of solid plasticizers are as follows:
1. Auxiliary thermal stability 2. Plasticizing property 3. Reducing energy consumption during processing 3. Excellent anti precipitation property 4. Good dispersion
