A professional who controls reactor vessels to polymerize raw resin materials to form phenolic, acrylic, or polyester resins. Respnsibilities include:

• Pumps specified amount of raw material into calibrated tank according to formula and transfers materials into reactor.
• Starts mixers and pumps reagents and catalysts into reactor.
• Starts circulation and vacuum pumps.
• Adjusts valves to regulate flow of preheated or cooled fluid around jacket of reactor and to start and regulate polymerization reaction.
• Adjusts valves to regulate pressure and temperature in reactor.
• Tests viscosity and pH of resins to determine length of polymerization time, using pH meters and viscosimeters.
• Turns valves to discharge processed materials from kettles into cooling pans.
• Records processing time, pressure, temperature, and test results in log; and writes daily reports on amounts of raw materials used and finished product barreled or stored.
• May dump compounds into polymerized resins to thicken product.
• May pump polymerized resin from storage tanks to tank trucks or cars for shipment.
• May cast liquid plastics in molds.
• May analyze sample of plastics materials to determine clarity, acidity, fusibility, or brittleness, using slide rule, torsion balance, and other testing equipment.