Porous Lightweight Polyimide Films with Ultra-High Surface Insulation Strength and Thermal Insulation for Space Solar...

Area of Science:

• Materials Science
• Aerospace Engineering

Background:

• Spacecraft solar arrays require robust surface insulation to prevent charging and discharging effects.
• Next-generation spacecraft demand higher voltage insulation capabilities for polyimide (PI) materials.

Purpose of the Study:

• To improve the surface insulation strength of polyimide (PI) for spacecraft solar arrays.
• To develop a novel porous PI film with enhanced electrical, thermal, and mechanical properties.

Main Methods:

• Controlled surface roughness and pore distribution of PI films using a pore-forming agent.
• Investigated the impact of pore-forming agent addition ratio on film properties.
• Evaluated flashover threshold, secondary electron yield, and thermal equilibrium temperature.

Main Results:

• A 50% pore-forming agent addition ratio yielded the highest flashover threshold (55.93 kV), a 201.7% improvement.
• Maximum secondary electron yield decreased from 2.01 to 1.32.
• Porous PI films exhibited lower thermal equilibrium temperature and stable performance after thermal shock.

Conclusions:

• Modulating PI surface roughness and pore distribution effectively suppresses secondary electron emission avalanches.
• The novel porous PI films demonstrate superior insulation strength, thermal management, and stability for space solar array applications.