Bulk Polymerization
With the ability to generate higher surface renewal with lower shear, LIST dry processing technology creates ideal high-vacuum plug-flow conditions that make it ideal for polycondensation reactions.

Polycondensation, or step-growth polymerization, forms the basis for many engineered plastics, adhesives, films and fibers, coatings, and most high performance polymers. Typical applications include the manufacture of polyester, nylon, and polyurethane. The process also presents a unique challenge.

During a polycondensation reaction, monomers and/or polymers with lower molecular weight are combined to form polymers with a higher molecular weight.  The reaction also creates an unwanted byproduct with a lower molecular weight. Unless removed, the lower weight byproduct will negatively affect the kinetics of the polycondensation reaction. 

LIST dry processing solutions generates the high temperatures and deep vacuum pressures needed to remove the lower molecular-weight byproduct quickly.  Within the closed environment, robust mixing and surface renewal helps vapor bubbles rise to the surface and dissipate, maximizing mass transfer efficiency.

Key Features and Benefits

For operators using polycondensation, LIST dry processing solutions provide key benefits that help ensure product quality and lower operating costs.

  • Protects shear-sensitive polymers with low, uniform shear rate.
  • High surface renewal transfers heat and mass while increasing devolatilization rate.
  • High turndown ratio allows for wider variation in throughput and capacity
  • Eliminates entrainment and plugging with a large vent area
  • Accommodates high viscosity masses, large working volumes, and long residence times.
  • Prevents local overheating and product degradation with a unique self-cleaning design.
  • Achieves plug flow with narrow residence time distribution
  • Operates under vacuum or pressure

Greater Flexibility – Lower Cost

Additionally, LIST dry processing solutions for polycondensation applications are highly flexible. They enable operators to process various polymer grades, in different solvents, with different melt viscosities without having to retool.