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        # Light and Strong: Choosing the Right Blowing Agent for Foam PVC

        

**Topic:** Additives

        

You're making foam-core pipes or lightweight footwear soles, but the bubbles are uneven. Some are huge, some are tiny, and the product feels 'crunchy'.

        
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## Problem

The quality of foamed PVC depends entirely on the decomposition rate of the blowing agent. If it releases gas too early or too late relative to the PVC fusion, you get poor cell structure and low mechanical strength.

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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 ADCL (Azodicarbonamide) is the industry standard for a reason. It has a predictable decomposition temperature that can be 'kicked' (lowered) using Zinc-based stabilizers. This allows you to time the gas release perfectly with the melt viscosity, resulting in a fine, uniform closed-cell structure.

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          ## Frequently Asked Questions

          
### Can I use ADCL for rigid foam board?

Yes, it is the primary choice for PVC foam boards used in signage and construction.

### How do I control the density?

Density is controlled by the PHR of ADCL and the processing pressure. Typically 0.5-2.0 PHR is used.

        
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By NBT Technical Desk · Updated 2026-06-07

        

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