An adhesive composition that improves structural integrity and insulative properties when applied to a cellulosic substrate is provided. The adhesive composition includes a plurality of microspheres and an emulsion-based polymer that has (i) an elastic modulus greater than 0.5 MPa in the range temperature range of 70° C. to 110° C.; (ii) an absolute log(E)/T slope of less than 0.05 in the range temperature range of 70° C. to 110° C.; and (iii) a tan d value less than 0.6 at 90° C.