Phase‐change composites silicone rubber/paraffin@SiO₂ microcapsules with different core/shell ratio for thermal management

Abstract

A series of paraffin (Pa)@silicon dioxide (SiO 2 ) microcapsules with different core/shell ratios were constructed by interfacial-polycondensation of tetraethoxysilane (TEOS) and γ-Methacryloxypropyltrimethoxysilane (MPS), and then were embedded in addition-cure liquid silicone rubber (ALSR) to fabricate ALSR/Pa@SiO 2 phase-change composites. The SiO 2 shell can avoid the leakage of Pa. Meanwhile, the in-situ modification of the SiO 2 shell by MPS can enhance the interface bonding between Pa@SiO 2 and ALSR, because the C═C bond introduced by MPS on the SiO 2 shell can participate in the curing reaction of ALSR. The study explored the effects of the core/shell ratio on the Pa@SiO 2 microcapsules and ALSR/Pa@SiO 2 composites. Differential scanning calorimetry analysis demonstrated that ALSR/Pa@SiO 2 composites have dependable thermal energy storage capability which can reach to 90.7 J g À1 and phase-change enthalpy of the composites increase with the core/shell ratio. The ALSR/Pa@SiO 2 composites were found as form-stable phase-change materials with low leakage rate, which is attributed to the protection of both SiO 2 shell and ALSR matrix. Due to the chemical interfacial interaction, the composites displayed improved mechanical strength. The composites can be used for thermal management and temperature regulation as an electronic packaging material. K E Y W O R D Saddition-cure liquid silicon rubber, core/shell ratio, electronic packaging, paraffin@SiO 2 microcapsules, thermal management

Thermo-Mechanical Behavior of Novel EPDM Foams Containing a Phase Change Material for Thermal Energy Storage Applications

“…Paraffin waxes are relatively cheap organic PCMs, known for their high heat of fusion, chemical stability, and availability in a large melting temperature range [ 10 ]. Due to their unique properties, they have been widely studied for thermal regulation of smart fabrics, sportswear, buildings, and electronic devices [ 6 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. To avoid leakage during the melting process, their confinement can be performed by encapsulation or shape-stabilization.…”

High-Sensitive Wearable Strain Sensors Based on the Carbon Nanotubes@Porous Soft Silicone Elastomer with Excellent Stretchability, Durability, and Biocompatibility

“…There is a peak at 1631 cm −1 in the FTIR spectrum of reagents A and B due to the C�C stretching vibration. 38 The intensity of the peak at 1631 cm −1 weakens in the FTIR spectra of SSE, which demonstrates that the vinyl-terminated PDMS has participated in the cross-linking reaction. The 1 H NMR spectra of reagent A, reagent B, and SSE are shown in Figure 2b.…”

“…Figure a shows the FTIR spectrum of reagent A, reagent B, and SSE. There is a peak at 1631 cm –1 in the FTIR spectrum of reagents A and B due to the CC stretching vibration . The intensity of the peak at 1631 cm –1 weakens in the FTIR spectra of SSE, which demonstrates that the vinyl-terminated PDMS has participated in the cross-linking reaction.…”

Valorization of sawdust biomass for biopolymer extraction via green method: Comparison with conventional process

“…The following bands were identified: stretching of hydroxyl groups bonded, OH in cellulose, hemicellulose and lignin (3334 cm −1 ), 67 CH 2 asymmetric stretching and stretching of CH 3 (2922 cm −1 ), CH 2 symmetric stretching in methyl and methylene (2853 cm −1 ), 68 C=O stretching of ester and acetyl in xylans (1740 cm −1 ), 69 absorbed OH + conjugated CO of lignin (1650 cm −1 ), 70 asymmetric CH 3 , symmetric CH 3 and CH 2 asymmetric bending modes (1465 cm −1 ), 71 CO skeletal stretching + CH 3 bending in amorphous zone of cellulose (1370 cm −1 ), 72 CH 2 symmetric bending in amorphous cellulose I (1420 cm −1 ), 73 CO stretching in cellulose and hemicellulose (1377 cm −1 ), 74 C‐O vibration in guaiacyl rings (1260 cm −1 ), 75 C‐O‐C asymmetrical stretching (1160 cm −1 ), 70 C‐O‐C symmetric stretching + OH associating band in cellulose and hemicellulose (1110 cm −1 ), 76 CO stretching of secondary alcohols (1049 cm −1 ), 77 OH out of plane deformation of carboxylic acids (945 cm −1 ) 77 and C‐O‐H bending out of plane (720 cm −1 ). The assignments of both types of SW (SW T1 and SW T2 ) indicate similar functional groups with some bands more intense than the others.…”