Melt Shear History and Contaminant Catalyzed Scission in Post Consumer Polyolefin Silo Blends
Deactivate metal catalysts and neutralize acid traces with targeted additives to stabilize viscosity drift and optimize landed cost per good recycled part.
Multi Point Thief Sampling
Meaning
Quality control protocols extract resin samples from several locations in a container to verify blend homogeneity before processing begins. Running multi point thief sampling ensures that additive levels, regrind ratios, and moisture content are uniform across the entire shipment. This procedure prevents the feeding of uneven resin mixtures into the injection moulding machine.
It helps avoid production defects like color variation and inconsistent part weight.
Quality Inspection
Resin shipments can settle during transport, leading to non-uniform particle distribution. Through multi point thief sampling, quality inspectors detect if additives migrated to the bottom of the container.
Process Control
Consistent resin composition is necessary for maintaining a stable melt viscosity and a predictable injection pressure. Implementing multi point thief sampling allows the moulding plant to verify that the resin from a silo or gaylord is uniform. This step reduces the need for machine adjustments during a production run.
It ensures that the moulding process remains within its validated operating window. This stability is critical for producing high-precision medical or automotive components.
Statistical Significance
A single sample from the top of a resin container is not representative of the entire batch. To achieve statistical significance, multi point thief sampling involves taking samples from multiple depths and radial positions. These individual samples are then analyzed separately or blended into a representative composite sample.
This rigorous sampling plan reduces the risk of accepting a non-conforming lot of resin. It provides a reliable basis for decisions regarding resin acceptance or rejection.