Properties of triple shape memory composites prepared via polymerization-induced phase separation

Area of Science:

• Polymer Science
• Materials Science

Background:

• Shape memory polymers (SMPs) are advancing with complex behaviors like triple shape memory.
• Achieving complex SMP behavior typically requires intricate material synthesis.
• Existing methods often involve complex compositions and synthesis routes.

Purpose of the Study:

• To develop a simplified synthesis route for triple shape memory polymers.
• To achieve triple shape behavior using polymerization induced phase separation (PIPS).
• To investigate the properties of epoxy and poly(ε-caprolactone) blends for shape memory applications.

Main Methods:

• Utilized polymerization induced phase separation (PIPS) for material synthesis.
• Developed two blends: one with semicrystalline epoxy, another with amorphous epoxy, both with poly(ε-caprolactone).
• Characterized the thermal and mechanical properties, and shape memory behavior of the blends.

Main Results:

• Both epoxy/poly(ε-caprolactone) blends exhibited distinct transition temperatures and three modulus-temperature plateaus for triple shape behavior.
• The semicrystalline epoxy blend resulted in an elastomeric material, while the amorphous epoxy blend was highly stiff at room temperature.
• Demonstrated independent programming and recovery of two distinct deformations in both systems.

Conclusions:

• A simple PIPS method enables the creation of triple shape memory polymers with tunable room-temperature properties.
• The developed materials can independently fix and recover two programmed shapes.
• Potential applications include multi-shape coatings, adhesives, and films due to facile fabrication.