1. Characteristics of improper addition of external lubricant in PVC foam products
Paraffin wax and PE wax are the most commonly used external slip agents in foaming products. Paraffin wax is easy to precipitate, so PE wax is generally used.

The external lubrication is insufficient, the temperature in zone 4 and 5 of the extruder is not easy to control, and it is easy to exceed the temperature. There are blisters, blisters, yellowing and rough plate surface on the plate surface; The increase of friction shear heat causes material decomposition, yellowing and paste on the plate surface, excessive external sliding and poor plasticization, resulting in scaling in the inner cavity of the mold and precipitation on the surface of the product, which is prone to uneven wall thickness and irregular back and forth movement of some symptoms on the surface.
2. Characteristics of improper addition of internal lubricant in PVC foam products
(1) Insufficient internal lubrication, poor dispersion of materials, uneven plasticization, difficult to control the thickness of products, thick in the middle and thin on both sides of the foam board, adhesion to the mold cavity and local overheating; Too much internal lubrication makes the foamed products brittle and the heat resistance decreases; Under the action of certain temperature and melting pressure, it is transformed into external lubrication, resulting in lubrication imbalance.

(2) Insufficient internal and external lubrication, high melt viscosity, high plasticizing torque, serious melt wall adhesion, yellow decomposition line on the material surface, poor surface smoothness and reduced mechanical properties of products; The internal and external lubrication is excessive, the plasticizing torque is small, and the melt plasticization is obviously insufficient. Although the product has good smoothness, the pressure point adhesion is poor, which seriously affects the mechanical properties of the product.
(3) There is less internal lubrication and more external lubrication, the plasticizing time is obviously prolonged, the plasticizing torque is reduced, the product is difficult to form and becomes brittle; There is more internal lubrication and less external lubrication, the plasticizing time is significantly shortened, there is a serious wall sticking phenomenon, the thermal stability time is shortened, and there are decomposition yellow lines on the product surface.

High density oxidized polyethylene wax is a high-performance lubricant both inside and outside, providing more excellent plasticizing and demoulding effects.

3. The internal and external lubrication is insufficient, the melt viscosity is large, the plasticizing torque is large, the melt wall sticking phenomenon is serious, the material surface has a yellow boundary, the surface smoothness is poor, and the mechanical properties of the product are low;
The internal and external lubrication are excessive, the plasticizing torque is small, and the melt plasticization is obviously insufficient. Although the product has good smoothness, the pressure point adhesion is poor, which seriously affects the mechanical properties of the product;
With less internal lubrication and more external lubrication, the plasticizing time is obviously prolonged, the plasticizing torque is reduced, and the product is difficult to form and brittle;
More internal lubrication, less external lubrication, significantly shorter plasticizing time, more serious wall sticking, shorter thermal stability time, and decomposition yellow lines on the product surface.
Qingdao Sainuo Chemical Co.,Ltd. We are manufacturer for PE wax, PP wax, OPE wax, EVA wax, PEMA, EBS,Zinc/Calcium Stearate…. Our products have passed the REACH, ROHS, PAHS, FDA testing.
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