Carbonization of Polydopamine-Coating Layers on Boron Nitride for Thermal Conductivity Enhancement in Hybrid Polyvinyl Alcohol (PVA) Composites

Abstract

Inspired by mussel adhesion proteins, boron nitride (BN) particles coated with homogeneous polydopamine (BNPDA) were prepared, and through an annealing process, a carbonized PDA layer on the surface of BN was obtained, which exhibited a nanocrystalline graphite-like structure. The effect of carbonization of PDA coating layer on BN particles was characterized by various analytical techniques including SEM, TEM, Raman spectroscopy, and XPS. When the resulting particles were used as a thermally conductive filler for polyvinyl alcohol (PVA) composite films, enhanced thermal conductivity was observed compared to raw BN composite due to the ordered structure and improved solubility in water. Furthermore, the homogeneous dispersion of the filler and excellent flexibility of the modified composite film with 21 wt % filler may be attributed to compatibility with the PVA chain. As the whole fabrication process did not use toxic chemicals (mainly water was used as the solvent), it may contribute to green and sustainable chemistry.

Water-soluble polyvinyl alcohol composite films with nanodiamond particles modified with polyethyleneimine

“…The Raman spectra of ND particles coated with PDA are in accordance with literature data. 48 After the ND-NH 2 particles were grafted with PEI, the I D / I G value increased by 0.27, which further indicated that PEI was successfully grafted onto the surfaces of the ND particles and the degree of functionalization was enhanced.…”

Electrospraying Graphene Nanosheets on Polyvinyl Alcohol Nanofibers for Efficient Thermal Management Materials

“…The initial decomposition temperature of PVA is approximately 245 °C, and most of the thermal degradation and physicochemical reactions of PVA occur between 245 and 550 °C. , At 700 °C, compared to H-PVA, the rGO contents of H-rGO/PVA-3, H-rGO/PVA-4, and H-rGO/PVA-5 are roughly calculated as 10.7, 13.7, and 26.3%, respectively. Compared with other recently reported polymer-based composites, such as PVA, carbon nitride nanosheets (CNNS)/PVA, surface-modified graphene (SMG)/poly(vinylidene fluoride) (PVDF), graphene nanoplatelets (GNPs)/PVA, rGO/PVA, BN/PVA, and BN/PEG/PVA, the in-plane thermal conductivity of the H-rGO/PVA films in this study have clear advantages (Figure e). The relevant data are summarized in Table .…”

Kinetic study of polydopamine sphere synthesis using TRIS: relationship between synthesis conditions and final properties

“…54–57 On the other hand, E. Coy et al 58 have reported contradictory results for synthesized PDA characterized by Raman spectroscopy without any thermal treatment, which shows characteristics related to carbonized PDA particles; this material displays regular zones that indicate nanocrystalline graphite-like structure. 59 In addition, according to polymers science, 60,61 characteristic endothermic peaks observed by DSC are associated with the fusion of crystalline regions present in the microstructure of polymers. 62 The crystalline fraction can be computed by the quotient of the melting enthalpy (heat associated with the fusion process) measured and the melting enthalpy of the completely crystalline material.…”

“…11 displays the Raman spectra of synthesized PDA; two distinct bands, D (amorphous band-sp 3 and H) and G (graphitic band-sp 2 ), are shown in all samples. The rst one, the D-band at ∼1374 cm −1 , and the second one, the G-band at ∼1579 cm −1 , originated from linear stretching of C-C bonds inside the rings and in-plane stretching of the aromatic rings, 59,73 respectively. The intensity ratio (I D /I G ) is utilized to identify the degree of defects in a material where a low ratio indicates a low number of defects; consequently, the material presents a more graphitic structure with an sp 2 phase.…”