Synthesis and characterization of microencapsulated paraffin with melamine-urea-formaldehyde shell modified with lignin

The study aims to fabricate MUF/paraffin microcapsules with lignin nanoparticles (LNPs)/ melamine-urea-formaldehyde (MUF) resin as hybrid shell material with different LNPs addition were synthesized in oil-in-water emulsion stabilized synergistically by styrene/maleic anhydride (SMA) and LNPs. The morphological characterization of LNPs was observed by transmission electron microscopy (TEM). The particle size of LNPs, the mean particle size and ξ potentials of SMA/LNPs mixture at pH =4.5 were investigated by zeta potential measurement. Field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analyzer (TGA), and differential scanning calorimetry (DSC) were characterized the morphologies, crystallography, chemical component, thermal stability and phase change properties of MUF/paraffin microcapsules with different LNPs addition. The results showed that MUF/paraffin microcapsules were spherical. The LNPs did not influence the chemical structure or crystal type of MUF/paraffin microcapsules. When the LNPs addition was 0.15 g, the melting enthalpy and crystallization enthalpy is respectively 130.03 and 121.92 J/g and the encapsulation efficiency of MicroC-15 is 61.04 %.