Note On the blowup criterion of smooth solution to the incompressible   viscoelastic flow
  We study the blowup criterion of smooth solution to the Oldroyd models. Let $(u(t,x), F(t,x)$ be a smooth solution in $[0,T)$, it is shown that the solution $(u(t,x), F(t,x)$ does not appear breakdown until $t=T$ provided $\nabla u(t,x)\in L^1([0,T]; L^\infty(\mr^n))$, $n=2,3$. 
Baoquan Yuan
math.AP