POS3-0739
A Solvent-Free Core–Shell Encapsulation Strategy for High-Performance RF Substrates
Topic
S3. Processing / Fabrications (Emerging Horizons in Polymer Processing and Fabrication)
When and Where
Sep 30, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Heesuk KIM
Jinhye BAE
Presenter(s)
Hyungkyu Kim (KIST)
Co-Author(s)
Abstract
A thermal filler can be made compatible with its polymer host without ever being chemically touched. The accepted way to bond an inert ceramic filler to a polymer matrix is wet-chemical treatment—yet every such treatment scars the filler and quietly destroys the thermal and dielectric advantages it was prized for. This trade-off has long capped composite substrates for high-frequency electronics, where heat must be removed without sacrificing signal integrity. Our approach sidesteps the dilemma: in a single dry, solvent-free step, mechanical energy drives a ductile fluoropolymer to wrap each rigid filler particle in a continuous shell, held together by triboelectric attraction rather than any chemical reaction. The crystal lattice that carries heat-bearing phonons emerges untouched. Because shell and matrix share the same molecular backbone, they fuse into one continuous phase with no detectable boundary, so heat crosses the interphase as if filler and polymer were a single material—while the insulating character that high-frequency circuits demand stays fully intact.
The payoff is a composite that conducts heat efficiently through its thickness yet loses almost no signal at high frequency, a pairing that has resisted earlier designs. The same interphase grips metal foil more tightly and curbs dimensional drift, meeting the practical demands of laminate manufacturing. To close the loop, we built a working substrate with embedded heating and printed circuitry: it ran cooler and preserved its signal far better under load. Needing no solvents, no additives, and leaving no defects—and readily transferable to other fillers—this dry encapsulation route opens a practical path to the multifunctional substrates that next-generation electronics will demand.
The payoff is a composite that conducts heat efficiently through its thickness yet loses almost no signal at high frequency, a pairing that has resisted earlier designs. The same interphase grips metal foil more tightly and curbs dimensional drift, meeting the practical demands of laminate manufacturing. To close the loop, we built a working substrate with embedded heating and printed circuitry: it ran cooler and preserved its signal far better under load. Needing no solvents, no additives, and leaving no defects—and readily transferable to other fillers—this dry encapsulation route opens a practical path to the multifunctional substrates that next-generation electronics will demand.
