Measuring Cyclic Oligomer Content in Synthetic Filament Extracted Yarns
Solvent extraction coupled with liquid chromatography isolates synthetic yarn cyclic oligomers to set strict delivery specs and stop knitting deposit failures.
Spinneret Deposit Buildup
Nozzle Obstruction
Melt spinning operations experience the accumulation of degraded polymer and additives on the outer surface of the extrusion plate. This spinneret deposit buildup, often called plate out, occurs when the polymer melt exits the holes and undergoes a rapid change in pressure. The residue consists of oxidized polymer chains and inorganic pigments that have migrated to the surface.
Extrusion Instability
Material accumulating around the orifice interferes with the laminar flow. As the spinneret deposit buildup grows, it can snag the emerging fiber, causing diameter variations.
Cleaning Interval
Maintenance schedules at the mill are dictated by the rate at which these residues form. Operators must perform a wipe down of the faceplate to remove the spinneret deposit buildup before it compromises the yarn quality. The use of silicone based release agents can extend the time between manual cleanings.
Thermal Degradation
High processing temperatures accelerate the oxidation of the melt at the air interface. If the spinneret deposit buildup is allowed to remain for too long, it can undergo carbonization and become difficult to remove without damaging the plate. Consistent temperature control and the use of antioxidants in the polymer chips are the primary defenses against this accumulation.