What’s believed to be the one and only twin-screw laboratory line to perform direct devolatilization is open for trial runs. JSW’s lab line, located at its North American Technical Center in Novi, Mich., is equipped with two twins.
The first is what JSW terms a “melter,” and its purpose is to mimic what occurs inside a polymer reactor (see illustration). Resin and solvents are fed into this machine, melted, and conveyed as a solution to the second twin. This machine is the devolatilization extruder, where water, solvents, and other residual volatiles are extracted. The polymer is then cooled and pelletized.
In North America, most resin suppliers extract volatiles from the polymer through a series of steam and water strippers. JSW says direct twin-screw devolatilization is more efficient and cost-effective because it offers greater temperature control and shorter residence times, which reduce the chances of polymer degradation and yield lower solvent content. JSW has been involved in extrusion technology and devolatilization for more than 60 years.
JSW’s tech center was relocated from near Indianapolis to Novi in 2006. Last year, the equipment was upgraded for devolatilization and dewatering trials. JSW runs about two devolatilization trials a month in Novi, says Scott Paulot, sales and marketing manager. JSW has 16 devol lines for trials in Hiroshima, Japan.