Preparation Optimization of CFRP and EPDM Composite by the Co-Curing Method

Area of Science:

• Materials Science
• Polymer Composites
• Aerospace Engineering

Background:

• Increasingly stringent aerospace technology demands necessitate improved solid rocket motor (SRM) case performance.
• Carbon fiber reinforced polymer (CFRP)/ethylene-propylene-diene monomer (EPDM) composites offer potential for advanced SRM applications.
• Optimizing the manufacturing process is crucial for achieving desired composite properties.

Purpose of the Study:

• To determine the optimal co-curing process for CFRP/EPDM composites.
• To enhance the mechanical properties and thermal stability of composites for SRM applications.
• To provide recommendations for SRM shell preparation.

Main Methods:

• Co-curing technique employed for CFRP/EPDM composite fabrication.
• Optimization of manufacturing parameters: temperature, heating time, and vulcanizing agent (DCP/S).
• Characterization using: Nuclear Magnetic Resonance (NMR) for crosslink density, peel strength test, interlaminar shear test (ILSS), Scanning Electron Microscopy (SEM) for interfacial analysis, and Thermogravimetric Analysis (TGA) for thermal stability.

Main Results:

• Optimum mechanical properties achieved at 160 °C for 20 min with DCP/S curing agent: crosslink density (3.459 × 10^-4 mol/cm³), peel strength (2.342 N/mm), and ILSS (82.08 MPa).
• SEM analysis revealed insights into the interfacial phase and bonding mechanisms.
• TGA confirmed favorable thermal stability for the EPDM/DCP/S system.

Conclusions:

• The co-curing technique, under optimized conditions (160 °C, 20 min, DCP/S), yields CFRP/EPDM composites with superior mechanical and thermal properties.
• The findings provide valuable data for the optimization of SRM shell manufacturing processes.
• This research contributes to the development of advanced materials for demanding aerospace applications.