Processes and compositions for cleaning mixing devices to improve polymer production

A process to clean melt processing equipment used to compound, mold, and/or extrude resins containing a polymer, comprising:

• purging the melt processing equipment with a cleaning mixture (purge) comprising:
• from 70 to 99 wt % of thermoplastic polymeric resin pellets, the pellets having a Rockwell R hardness of from 85 to 140 as measured by ASTM D785;
• and
• from 1 to 30 wt % of an aqueous solution that contains 0.2 to 30 wt % of a surfactant salt selected from at least one of the following:
• sulfonate salts, alkyl aryl sulfonate salts, alkyl sulfate salts, C6 to C36 carboxylic acid salts, and mixtures thereof, wherein the aqueous solution has a pH of 6.0 to 9.0;
• and
• running the melt processing equipment at a temperature of from 200 to 380° C. to obtain a purged resin while cleaning the melt processing equipment.