As for the internal lubrication of lubricant, as far as PVC is concerned, it can be regarded as the same kind of material as plasticizer, which plays a role of plasticization or softening. The difference is that the lubricant has a lower polarity and a longer carbon chain. Therefore, compared with plasticizers, the compatibility of lubricants and polyvinyl chloride is significantly reduced. It is precisely because of the low compatibility of lubricants and polyvinyl chloride ( And there is a certain compatibility), so only a small amount of lubricant molecules can penetrate between the molecular chains of the polymer like plasticizers, weakening the mutual attraction between the molecular chains, and when the polymer is deformed, the molecular chains It is easier to slide and rotate with each other, while not excessively lowering the glass transition temperature of the polymer.
||High density Oxidized Polyethylene Wax OP-25
||25 mg KOH/g
|Hardness @ 25°C (77°F)
||PVC lubricant, PVC stabilizers
||AC 316A, Luwax OA6
1. Without any effects on the fusion time.
2. Improve the melt flowability.
3. Without any effects on transparency.
4. Provide lubricating property without lowering melt-strendth.
What happens if the PVC lubricant is not used well?
The role of PVC lubricants in PVC processing is no less than that of stabilizers. Its use generally needs to follow strict principles, such as internal and external slip balance, moderate amount, etc.
Unbalanced internal and external lubrication.
Too much external slippage, although the extrusion speed is fast, but the material is easy to produce, poor plasticization; too much internal slippage, large extrusion volume, the material plasticization is not good. If the initial lubrication is not good, the extrusion torque will be too large. Insufficient lubrication in the later period will lead to insufficient lubrication in the screw homogenization section, compression section, and die section, and the material shears violently, which will affect the surface quality and internal performance of the extruded product.