Radiation curable coating adhesion promoter and preparation method thereof

The invention discloses a radiation curable coating adhesion promoter and preparation method thereof. The adhesion promoter is of a linear structure, one end in the molecular structure is provided with (methyl)acrylate double bond, the other end is a carboxyl structure, and the middle skeleton chain section is poly epsilon-caprolactone molecular structure. The preparation method comprises the following steps: 1) adding (methyl)hydroxethyl acrylate, epsilon-caprolactone, a catalyst and a polymerization inhibitor in a reaction bottle, stirring and reacting at 140-180 DEG.C for 2-8 hours; 2) cooling to 80 DEG.C or above, adding anhydride, uniformly stirring, heating up to 120-140 DEG.C, keeping temperature for 2-6 hours; 3) cooling to 40-60 DEG.C and filtering to prepare the product. The adhesion promoter disclosed by the invention has the characteristic that the poly epsilon-caprolactone skeleton chain section is additionally added to the adhesion promoter in comparison with the conventional radiation curable coating adhesion promoter; and the preparation process is simple and molecular chain section and the molecular weight are strong in controllability.