A tackifier resin is provided comprising monomer units from at least one aromatic monomer and at least one acrylate monomer; wherein the tackifier resin has a low residual monomer concentration. In other embodiments of the invention, the tackifier resin does not significantly decrease the moisture vapor transport rate of an adhesive composition comprising the tackifier resin, does not significantly increase fogging of an adhesive composition comprising the tackifier resin, and does not significantly exhibit skin sensitivity properties. A process to produce the tackifier resin is also provided. The process comprises contacting a tackifier resin product stream with at least one carrier at a temperature sufficient to remove a portion of at least one residual monomer from the tackifier resin product stream to produce the tackifier resin.