Continuous mixing for highly viscous materials

A method comprising:

• feeding at least one polymer additive into a continuous mixer at a first feed rate;
• heating the at least one polymer additive to a first temperature to form at least one heated polymer additive, wherein the first temperature is greater than a melting temperature of the at least one polymer additive;
• heating an abrasive solid material to a second temperature to form a heated abrasive solid material;
• feeding the heated abrasive solid material at the second temperature into the continuous mixer at a second feed rate;
• mixing the heated abrasive solid material and the at least one heated polymer additive in the continuous mixer to form a first mixture;
• rolling the first mixture with a plurality of heated rollers to a selected thickness;
• and
• cutting the rolled first mixture.