Comprehensive Performance Regulation and Characterization of Polypropylene/Elastomer Composite Insulation Materials

Area of Science:

• Materials Science
• Polymer Science
• Electrical Engineering

Background:

• Polypropylene (PP) is a key material for recyclable cable insulation.
• Improving both mechanical and electrical properties of PP is crucial for advanced applications.
• Understanding the role of elastomers in PP composites is essential for material development.

Purpose of the Study:

• To investigate the synergistic mechanism for enhancing mechanical and electrical properties of PP using elastomers.
• To analyze the impact of elastomers on the microstructure, aggregation structure, and carrier migration in PP composites.
• To identify optimal PP/elastomer compositions for cable insulation.

Main Methods:

• Microstructure analysis
• Crystallization studies
• Mechanical property testing (tensile strength, modulus, elongation at break)
• Electrical property testing (breakdown strength, volume resistivity)
• Analysis of PP/elastomer composites with varying elastomer content.

Main Results:

• Elastomers improve tensile strength and elongation at break while reducing tensile modulus in PP.
• Enhanced compatibility between elastomer and PP matrix creates amorphous regions and crystalline-amorphous interfaces.
• These interfaces act as deep traps, reducing carrier mobility and improving electrical properties.
• Breakdown strength and volume resistivity initially increase with elastomer content, then decrease.
• PP/PBE-2 composite demonstrated superior mechanical and electrical properties.

Conclusions:

• Elastomer addition offers a viable strategy for synergistic enhancement of PP's mechanical and electrical properties.
• The microstructure modification induced by elastomers is key to improved performance.
• PP/PBE-2 is identified as a promising recyclable insulation material for high-voltage cables.