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

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 morphologies, chemical structures, 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 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 paraffin droplets in situ polymerization and reduce the need for surfactants.