Naphthalene-Modified Cationic Initiators for Superior Polymerization Stability and Thermal Conductivity in Epoxy...

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Epoxy resins are crucial for thermal management but often suffer from limited curing lifetimes.
• Maintaining ordered structures in liquid crystalline (LC) epoxies during network formation is vital for phonon transport.

Purpose of the Study:

• To develop naphthalene-modified cationic initiators with tunable counteranions.
• To extend epoxy curing lifetime for controlled network formation.
• To enhance thermal conductivity in epoxy systems.

Main Methods:

• Synthesis of naphthalene-modified cationic initiators.
• Differential scanning calorimetry (DSC) to analyze polymerization.
• X-ray diffraction (XRD) to assess mesogenic order preservation.
• Thermal conductivity measurements of cured epoxy systems.

Main Results:

• Extended initiator lifetime enabled efficient formation of high-ordered networks in LC epoxies.
• DSC showed controlled polymerization with uniform heat release.
• XRD confirmed preservation of mesogenic order and π-π stacking.
• Unfilled LC epoxies achieved high thermal conductivity (0.86 W m⁻¹ K⁻¹).
• Hexagonal boron nitride (h-BN) filled epoxies reached 25.08 W m⁻¹ K⁻¹.

Conclusions:

• Rational initiator design is a simple strategy for fabricating high-purity, thermally conductive epoxy networks.
• These materials are suitable for advanced thermal management applications.
• The developed initiators facilitate the creation of reprocessable epoxy networks with enhanced thermal properties.