Organic-inorganic composite resin, coating composition containing the same and application thereof

An organic-inorganic composite resin, derived from:

• (A) an inorganic portion comprising (a1) one or more siloxane monomers of formula (R1)nSi(OR2)4-n, wherein R1 is independently H, phenyl, C1-6 alkyl or a monovalent organic group with an end group selected from the group consisting of amino group, epoxy group, vinyl group, isocyanate group, mercapto group or (meth)acryloxy group;
• R2 is C1-3 alkyl;
• and n is an integer from 0 to 3;
• (a2) an acidic catalyst;
• (a3) silica;
• and (a4) a siloxane oligomer;
• and
• (B) an organic portion comprising (b1) one or more acrylic monomers;
• wherein the amount of the (a4) siloxane oligomer ranges from 5 wt % to 23 wt % of the total weight of the solid content of the inorganic portion, and
• wherein the weight ratio of the inorganic portion to the organic portion ranges from 2:8 to 8:2.