Preparation and characterization of n-dodecanol microcapsules in poly (methyl methacrylate)

The N-dodecanol-polymethyl-metharylate(DA@PMMA) microcapsules were prepared by suspension polymerization method with n-dodecanol (DA) as core material and polymethyl-metharylate (PMMA) as outer shell. Microcapsules were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analysis (TGA), et al. The results show that the best conditions for preparation of DA@PMMA microcapsules are:Sodium salt of styrene-maleic anhydride polymer (SMA) content is 7.5% to DA, 2, 2-azobisisobutyronitrile (AIBN) content is 7.5% to methyl methacrylate (MMA), the core/shell mass ratio is 2:1, stirring speed is 1 000 r/min. DA@PMMA microcapsules are sphericalthe average particle size of DA@PMMA microcapsules is 26 μm. The mass fraction of DA in DA@PMMA microcapsules is nearly 66% and the latent heats of melting and freezing are found to be 137.6 J/g and 132.8 J/g. TGA and FIIR analyses also indicate that DA@PMMA microcapsules have good stability.