Common Challenges in EVA Clog Production—and How Manufacturers Are Solving Them

As consumers expect EVA clogs to become softer, lighter, and more comfortable, manufacturers are facing new production challenges. Improving softness is no longer difficult—the real challenge is maintaining stable quality at the same time.

Here are some of the most common issues seen in EVA footwear production.

1. Shrinkage After Foaming

Reducing hardness often increases the risk of shrinkage after molding. Shoes may deform during cooling, leading to size differences, left-right mismatch, and higher rejection rates.

The key is to improve melt strength instead of simply adjusting the foaming formula.

2. Mold Sticking

Many factories spend valuable production time cleaning molds.

In low-hardness EVA formulations, additives such as zinc oxide or zinc stearate can migrate to the surface during foaming, making demolding more difficult and reducing production efficiency.

3. Soft Feel but Weak Support

A softer shoe doesn't always mean a better shoe. Some formulations become too loose after foaming, resulting in poor rebound, weak support, and an overall lower-quality feel.

The ideal material should provide softness while maintaining resilience and dimensional stability.

A Better Material Solution

To solve these problems, VIKEM offers a new EVA footwear performance modifier designed for low-hardness foam applications.

Compared with conventional formulations, it helps:

• Reduce shrinkage after foaming

• Improve mold release and reduce mold sticking

• Deliver a softer, rubber-like touch

• Maintain good rebound and dimensional stability

• Improve foam cell uniformity and finished appearance

According to internal testing, shrinkage was reduced from 6.51% to 4.53%, while rebound performance also improved under the same density and hardness conditions.

Whether you're producing EVA clogs, sandals, or foam midsoles, choosing the right modifier can make production more stable and improve finished product quality.

If you're experiencing similar issues in your EVA footwear production, the VIKEM technical team is ready to discuss your formulation and recommend a suitable solution.