Linked　polyurethane-acrylate　(LPUA)　emulsions　with　good　stability　were　synthesized　by　seed　swelling　emulsion　polymerization.　We　then　investigated　the　thermal　degradation　process　of　the　LPUA　film　by　means　of　thermogravimetry-derivative　thermogravimetry　(TG-DTG)　at　different　heating　rates.　It　was　shown　that　the　heating　rate　had　obvious　influence　on　the　thermal　weight　loss　of　LPUA.　Both　the　starting　and　ending　temperatures　of　decomposition　shifted　to　a　higher　temperature　with　increased　heating　rate.　The　most　probable　kinetic　parameters　of　decomposition　were　obtained　from　the　Coats-Redfern　integral　equation　and　Achar　differential　equation.　It　was　shown　that　the　optimum　mechanism　functions　of　the　decomposition　reaction　were　3D　diffusion,　spherical　symmetry,　D4,　and　deceleration　type　a-t　curve.　The　thermal　decomposition　mechanism　function　of　the　LPUA　film　was　f(alpha)=3/2[(1-alpha)(-1/3)-1](-1);G(alpha)=(1-2　alpha/3)-(1-alpha)(2/3).