When a converter opens a container of resin and finds discoloured pellets, dust or moisture, the instinct is to question the producer. In our experience that is the wrong first suspicion. Prime resin leaves a modern petrochemical complex under controlled conditions. What happens over the following four to six weeks is where the risk sits.
The three failure points
Container condition. Standard dry containers carry residues from previous cargo. A container that last moved cement, fertilizer or chemicals will contaminate bulk-loaded resin regardless of how clean the pellets were at the plant. Bulk polymer must be loaded into a fitted liner, and the container must be inspected before the liner goes in.
Bag specification. A 25 kg bag that is adequate for a short domestic truck movement is not adequate for six weeks at sea through a humid transit. Polyethylene bags without an inner moisture barrier will admit humidity; hygroscopic resins such as PET and ABS will arrive requiring extended drying, and the converter will pay for that in energy and cycle time.
Stack and handling. Jumbo bags stacked beyond their rated height rupture at the seam. Pallets loaded without corner protection allow bags to abrade against container walls, opening slow leaks that admit moisture and contamination across the whole voyage.
The pellet was clean when it left. The question worth asking is what you put it in, and what was in there before.
What a properly specified consignment looks like
- Container inspected and certified clean before liner installation, with prior cargo recorded.
- Moisture-barrier inner liner on all hygroscopic resins, regardless of route length.
- Bag construction specified against transit humidity and duration, not against lowest cost.
- Stack height limited to the bag’s rated load, with the limit stated on the packing instruction.
- Pallet corner protection and stretch wrapping on all palletised movements.
- Retained sample held against the shipment reference, so any claim can be tested against what was actually loaded.
The commercial point
Correct packing adds a small amount to the landed cost and removes the single most common cause of claim, rejection and delay in resin trade. Buyers comparing two offers that differ by a few dollars per tonne should establish which packing specification each price reflects before treating the numbers as comparable.