FTIR Spectrum Analysis of Polyamide Pellets
A client blended a UV Inhibitor with a polyamide pellet to be used in manufacturing. Thin white residue began appearing on the surfaces of the pellets. It was thought the UV Inhibitor might have "bloomed" to the surface, it was determined a full analysis would reveal the root cause.
What NH Chemical Analysis Team Did
The staff needed to understand several key factors for this particular problem.
- What analysis techniques would be required?
- The polymers and chemicals in question?
Both the final product and the polyamide pellets with the UV stabilizer were sent to our lab for analysis.
An FTIR spectrum was taken of the thin white residue on the final product and it appeared to be that of a hindered Amine stabilizer. When the pellets were examined under a microscope, a similar white residue was noticed on the surface of the pellets. An FTIR spectrum revealed that the white residue on the pellets matched the white residue on the final product, which was found by FTIR to be a hindered amine UV stabilizer.
Apparently the UV stabilizer was poorly blended with the original polymer, or else it had migrated to the surface of the pellets themselves and did the same when molded into the final product. Either improper blending of the polymer and additives or the wrong UV stabilizer for that particular polymer was the root cause of the problem.
Customer Benefit and Result
The client confirming suspicion with the FTIR analysis knows the blending of the ploymer additives needs to be more thorough to prevent future problems.