Polyamides are widely used engineering plastics, but their performance often needs to be further adjusted by blending with other polymers. Due to polarity differences, most PA-based blends require compatibilizers to ensure stable morphology and mechanical integrity. Recent studies on PA/PP and PA/PC blends have provided new insights into compatibilization mechanisms and material optimization.
In PA/PP blends, poor interfacial adhesion caused by large polarity differences leads to severe phase separation. Maleic anhydride-grafted polypropylene (PP-g-MAH) remains the most widely used compatibilizer. Its anhydride groups react with amine end groups of PA, forming stable chemical bonds that strengthen the interface. With deeper research, it has become clear that grafting efficiency, MAH content, and molecular weight distribution significantly influence the final toughness and processability of the blend.
Block copolymer compatibilizers represent a newer direction, enabling finer phase dispersion and better toughness. Nanoparticle-assisted compatibilization has also emerged, improving long-term thermal resistance and fatigue behavior of the blends.
For PA/PC blends, the challenge lies in mismatched processing temperatures and complex interfacial chemistry. Epoxy-functional compatibilizers have proven highly effective, forming chemical linkages with both PA and PC end groups. As a result, thermal stability, impact strength, and dimensional stability at elevated temperatures have greatly improved.
Recent developments focus on reaction rate control, ensuring that compatibilization occurs at lower temperatures to prevent PC degradation. Additives containing silicon or flexible chain segments further enhance transparency, weather resistance, and chemical durability.
Compatibilization strategies are becoming increasingly sophisticated, enabling nylon blends to meet the stringent requirements of automotive, electrical, and structural applications.
