Combined stabilizers prepared from cellulose nanocrystals and styrene-maleic anhydride to microencapsulate phase change materials

Abstract Cellulose nanocrystals (CNCs) combined with styrene-maleic anhydride (SMA) as stabilizers were used to stabilize paraffin droplets for fabricating paraffin/melamine-urea-formaldehyde (MUF) microcapsules. Effects of mixed emulsifier of CNCs and SMA on the morphology, chemical structure, and properties of paraffin/MUF microcapsules were characterized by Field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analyzer (TGA), differential scanning calorimetry (DSC), and paraffin leakage rate test. The results showed that using CNCs alone as emulsifier did not work in the manufacturing paraffin/MUF microcapsules, but mixed emulsifier of CNCs and SMA was suitable. When CNCs and SMA each account for 50% of the mixed stabilizer, the phase change latent heat values of melting and crystallization of MicroC5S5 were about 123.6 J/g and 118.4 J/g, respectively. This demonstrates that CNCs can be mixed with SMA to stabilize in situ polymerization and reduce the need for surfactants.