Lubricating Wax Additives for High-Fill Rigid PVC Profiles

Introduction

High-fill rigid PVC profiles, especially those with heavy calcium carbonate loading, are widely used in windows, doors, and construction panels. While fillers reduce material cost and improve rigidity, they also significantly increase melt viscosity, making extrusion more challenging. Proper selection of lubricating wax additives can balance melt flow, heat stability, and final product quality.

Industry Challenges

• Poor Melt Flow: High filler content hinders polymer chain mobility.

• Surface Defects: Increased viscosity causes flow marks and rough surfaces.

• Dimensional Instability: Inconsistent shrinkage during cooling.

How Wax Additives Work

• Internal Lubrication: Polyethylene and amide waxes reduce friction between PVC molecules, improving flow without compromising fusion.

• External Lubrication: Paraffin and Fischer-Tropsch waxes create a thin layer between the melt and the metal surface, preventing sticking and reducing die build-up.

Technical Insights

An optimized blend of internal and external lubricants ensures fast gelation, smooth extrusion, and high-gloss surfaces, even at high filler ratios. Adjusting melt temperature and screw design further enhances performance.

A profile manufacturer producing high-fill PVC window frames integrated a dual-lubricant wax system. The result: 20% faster extrusion speed, fewer die deposits, and improved surface gloss.

Maximize your rigid PVC profile production efficiency with our advanced wax lubrication solutions. Contact us for a customized formulation and process support.