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        # Speed Up Your Line: The Impact of Stearic Acid on Processing

        

**Topic:** Additives

        

Your extruder is running hot, and your output is lower than expected. You're pushing the machine to its limit, but the material just won't move faster.

        
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## Problem

Internal and external friction are the enemies of high-speed extrusion. If the PVC melt sticks to the metal surfaces of the barrel and screw, it slows down and risks localized overheating (degradation).

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## Likely cause

This issue often stems from inconsistent compounding temperatures, inferior raw material purity, or unbalanced stabilizer ratios within the formulation matrix.

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## Corrective direction

NBT PVC-Grade Stearic Acid acts as a highly effective external lubricant. It forms a thin film between the melt and the metal, reducing torque and allowing for higher screw speeds. It also improves the surface gloss of the final product. Just be careful - too much will cause 'slippage' and reduce output.

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          ## Frequently Asked Questions

          
### What is the difference between rubber grade and PVC grade stearic acid?

PVC grade has a specific C16/C18 ratio optimized for metal release and compatibility with PVC stabilizers.

### Does it affect transparency?

In small amounts (0.5-1.5 PHR), it has minimal impact on clarity.

        
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By NBT Technical Desk · Updated 2026-06-07

        

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