From Static Coating to Adaptive Interphase: A T_g-Mismatch-Driven Dual-Component Sizing Strategy for High-Temperature...

Area of Science:

• Materials Science
• Polymer Science
• Composite Materials

Background:

• High-temperature thermoplastic composites face challenges in achieving stable and responsive fiber-matrix interfaces.
• Existing methods often struggle to balance thermal stability with the need for adaptive interfacial properties.

Purpose of the Study:

• To develop a novel sizing strategy for controllable interfacial evolution in carbon fiber-reinforced poly(phthalazinone ether sulfone ketone) (CF/PPESK) composites.
• To enhance thermal stability, mechanical performance, and adaptive responsiveness of high-temperature composites.

Main Methods:

• A dual-component colloidal suspension sizing strategy using a rigid poly(amic acid) salt (PAAs) precursor and a flexible sulfonated poly(phthalazinone ether sulfone ketone) (SPPESK).
• Codeposition onto carbon fibers followed by hot-press processing to induce spontaneous phase reconstruction based on glass transition temperature (Tg) differences.
• Atomic Force Microscopy (AFM) modulus mapping to analyze interfacial structure and molecular interpenetration.

Main Results:

• The proposed strategy created a synergistic interfacial architecture with a rigid skeleton and compliant penetration layer, enhancing wettability and compatibility.
• Composites showed significant improvements: 41.3% increase in interlaminar shear strength and 43% increase in flexural strength.
• Maintained over 60% of mechanical performance at 250 °C, with a smooth modulus-gradient interphase of approximately 300 nm.

Conclusions:

• The Tg-difference-driven dual-component sizing strategy enables dynamic adaptive interfacial design for high-performance thermoplastic composites.
• This water-based, environmentally benign approach is applicable to various matrices and reinforcement forms, improving interfacial strengthening and wear resistance.
• Provides a universal paradigm for developing advanced composites with enhanced thermal and mechanical properties.