Macrocyclic oligomeric silsesquioxane, modified organosilicon packaging adhesive thereof and preparation method thereof

The invention relates to macrocyclic oligomeric silsesquioxane, a modified organosilicon packaging adhesive thereof and a preparation method thereof. According to the invention, the macrocyclic oligomeric silsesquioxane (MOSS) (component A) and hydroxyl-terminated vinyl polysiloxane (component B) are synthesized, then the components A and B are mixed according to a mass ratio of 1:(1-5), and then a chloroplatinic acid catalyst is used for carrying out hydrosilylation curing for preparing the MOSS modified organosilicon packaging adhesive for LED packaging. The preparation method has a simple process and high synthetic yield; and the packaging adhesive has good heat stability, higher refractive index and good light transmittance and can be cured at lower temperature. The light transmittance of the prepared MOSS modified organosilicon packaging adhesive at a wavelength of 500nm is over 90%, the refractive index at a temperature below 25 DEG C is 1.535, the thermal decomposition temperature of the packaging adhe