Was there a product failure because of a polymer process problem?
This weekend you will see many bright orange plastic pumpkins filled with candy and treats. These pumpkins are usually made of the thermoplastic family of polymers. According to Plastics Europe, the Association of Plastics Manufacturers, plastics are derived from organic products. The materials used in the production of plastics are natural products such as cellulose, coal, natural gas, salt and, crude oil. Here is the Association’s explanation of how plastic is produced:
The two major processes used to produce plastics are called polymerisation and polycondensation, and they both require specific catalysts. In a polymerisation reactor, monomers like ethylene and propylene are linked together to form long polymers chains. Each polymer has its own properties, structure and size depending on the various types of basic monomers used.
There are many different types of plastics, and they can be grouped into two main polymer families: Thermoplastics (which soften on heating and then harden again on cooling) [and] Thermosets (which never soften when they have been moulded).
If you are trying to understand the difference between thermosets and thermoplastics, this Fantastic Plastics! YouTube video is a great resource.
If problems arise during thermoplastic production, those molded plastic pumpkins could be compromised. If there is a polymer process problem, the orange color could be off, or little bubbles or speckles could be embedded in the pumpkin, or maybe the shape came out a little warped.
When problems like these crop up, manufacturers use Fourier Transform Infrared (FT-IR) technology to do failure analysis and determine the cause of the problem. The FTIR technique is commonly used in quality control and problem solving in manufacturing.
The most popular and easy-to-use technique available in modern Fourier Transform Infrared (FT-IR) spectrometers is ATR, or Attenuated Total Reflectance, using diamond crystals. ATR enables samples to be examined directly in the solid or liquid state without further preparation. If the pumpkin had hazing, streaking or an incorrect color, ATR could indicate that there was a problem of improper formulation, including additives or fillers, contamination, or poor mixing.
If the pumpkin had roughness, speckles, mars, or bubbles, ATR could help determine that there was contamination of the surface or an embedded processing problem like trapped gas. And if your pumpkin is warped and misshapen enough to look like it belongs in Edvard Munch’s The Scream painting, then maybe incorrect processing conditions existed during the manufacturing process.
A quick infrared scan of the failed and control parts using FTIR instrumentation could yield spectra which can be compared to the reference spectra of the quality products.
If your manufacturing facility is experiencing some plastic and polymer problems, we have a free online step-by-step analysis guide to help you evaluate challenging samples, find the symptom, and learn how to solve the problem from sample prep to data analysis. It will even show you which spectroscopy solution will help your analysis.
So if you are a manufacturer of plastics pumpkins, make sure you identify and solve your polymer problems before your products get into customer hands. After all, the only time you want trick-or-treaters to scream is when they encounter some witches, goblins, and ghosts — not because their parents bought defective pumpkin buckets.
October 25-31, 2015 is National Lead Poisoning Prevention Week