Method of forming shaped articles

In a method of forming a shaped article comprising mixing a liquid polymer containing functional end groups with a suitable compounding agent that yields a mixture capable of Newtonion flow at the mixing temperature and moving the mixture under a pressure differential of 10 to 3000 pounds per square inch to a shaper and curing, the improvement wherein the mixture is subjected to mixing in a vacuum in a high shear mixer to convert the mixture from a Newtonion to a non-Newtonion mixture at the mixing temperature, mixing a curative in the non-Newtonion mixture and moving the mixture to shaper at a viscosity at the mixing temperature expressed as 100,000 to 750,000 poises at 60.degree. C.