Interfacial Engineering for the Synergistic Enhancement of Thermal Conductivity of Discotic Liquid Crystal Composites

Abstract

To develop an advanced heat transfer composite, a deeper understanding of the interfacial correlation between matrix and filler is of paramount importance. To verify the effect of interfacial correlations on the thermal conductivity, the conductive fillers such as expanded graphite (EG) and boron nitride (BN) are introduced in the discotic liquid crystal (DLC)-based polymeric matrix. The DLC matrix exhibits better interfacial affinity with EG compared to BN because of the strong π-π interactions between EG and DLC. Thanks to its excellent interfacial affinity, the EG-DLC composites show a synergistic increment in thermal conducting performance.

Significant enhancement of thermal conductivity in graphite/polyester composite via interfacial π–π interaction

“…This intriguing phenomenon, which was also found in Kang et al . 's work, is mainly due to the interfacial affinity between pristine graphite and LCP. LCP itself contains a large amount of phenyl pendant groups which could correlate with graphite by a π–π interaction .…”

“…In order that enhanced efficiency of the TC in this work could be compared with other literature, an enhancement factor was incorporated. The definition of the enhancement factor is as follows: where K c and K p are the TC of composite and polymeric matrix respectively.…”

Flame‐retardant and thermal degradation mechanisms of melamine polyphosphate in combination with aluminum phosphinate in glass fabric‐reinforced epoxy resin

“…It is well known that materials with similar surface energy values present similar chemical characteristics and thus display a high interfacial affinity . To determine the surface energy values of EP and flame retardants, static water contact angle was measured on a goniometer.…”

The Effect of Interfacial Affinity on Thermal Conducting Performance of Liquid Crystalline Composites

“…Motivated by the requirement for a thermal conducting organic matrix, polymerizable liquid crystalline (LC) monomers, LC-ene and LC-thiol, were synthesized [4]. The synthesized LC network was served as a polymeric matrix for heat releasing composites packed with expanded graphite (EG) or hexagonal boron nitride (BN) [5]. As predictable, thermal conductive property of both composites were enhanced by increasing the additives [5].…”

“…The synthesized LC network was served as a polymeric matrix for heat releasing composites packed with expanded graphite (EG) or hexagonal boron nitride (BN) [5]. As predictable, thermal conductive property of both composites were enhanced by increasing the additives [5]. Comparison of theoretical model with experimental measurement of thermal conductivity of LC-EG and LC-BN composites, it was recognized that LC-EG composite showed better thermal conductive performance than LC-BN composite at same filler amount although the thermal conductivity value of BN itself is higher than EG [5].…”