Calcium carbonate has become a key functional filler in PP, PE, PVC, and engineering plastics. Here are common questions from industry users.

1. Why is calcium carbonate added to plastics?

It enhances stiffness, rigidity, dimensional stability, and heat resistance. Fine CaCO₃ reduces shrinkage and warpage, making molded parts more precise and stable. It also lowers production costs by decreasing resin consumption.

2. How does CaCO₃ improve plastic strength?

Its micro-sized particles reinforce the polymer matrix, increasing mechanical properties such as tensile strength, impact resistance (especially treated CaCO₃), and hardness. It also improves scratch resistance in PP and PE products.

3. Does calcium carbonate affect plastic processing?

Yes, in a positive way. CaCO₃ improves extrusion stability, shortens molding cycles, enhances cooling performance, and reduces deformation during processing. It also increases the output of extrusion lines.

4. Is calcium carbonate safe for food-contact plastics?

Food-grade CaCO₃ is approved in many regions and is commonly used in packaging films, containers, and masterbatch. High purity ensures low heavy-metal content and safe human contact.

5. What plastic products commonly use CaCO₃?

PP modified granules, PVC pipes, cable insulation, injection-molded household goods, high-calcium masterbatch, automotive plastics, woven bags, and foam products all rely on CaCO₃ for performance enhancement.