Compounded Polymer Analysis
We have the capabilities and experience to analyze compounded polymers. The analysis can be performed on pellets, manufactured components, or actual products. Typically, the analysis includes examination of:
- Polymer components
- Process aids
- Plasticizers
- Lubricants
- Stabilizers
- Fillers
Compounded polymer analysis is performed at a wide range of levels to meet the specific requirements of the client. In some cases, the question to be answered is simply, “what kind of plastic is this?”
In other cases, at the other extreme, the question may be, “is this compounded polymer substantially similar to another compounded polymer?”
This more extreme case of compounded polymer analysis is typical of:
- Deformulation
- Reverse-engineering
- Industrial espionage issues
- Patent infringement evaluations
- Polymer components
- Process aids
- Plasticizers
- Lubricants
- Stabilizers
- Fillers
- Deformulation
- Reverse-engineering
- Industrial espionage issues
- Patent infringement evaluations
Benefits of Compounded Polymer Analysis
The polymer component of a plastic or rubber material sets the base properties of the material and is usually tailored to the specific application based on design parameters. Frequently the polymer component is a blend of several different plastics. We can separate and characterize the polymer components using gel permeation chromatography (GPC), fraction collection, and nuclear magnetic resonance spectroscopy (NMR). Polymer structural analysis and molecular weight distribution information are obtained. In some cases, Fourier transform infrared spectroscopy (FTIR) provides the level of polymer identification that is needed to cost-effectively advance your program. Thermal methods of analysis supply the details regarding glass transition temperature, melting and crystallization temperature zones, reaction energies in the case of thermoset crosslinked systems, and the viscosity and rheological (flow) properties of the polymers.
Additives are critical to the performance of compounded polymer systems. Depending on the molecular weight of the additives, and the ability of the additive to be dissolved or vaporized (or not), specific analytical methods are employed to determine the identity and quantity of additives. For example, plasticizers, lubricants, mold release agents, and process aids can be evaluated using gas chromatography with mass spectrometric detection or high performance liquid chromatography (HPLC) with an array of detectors. Some clients are simply interested in whether or not the compounded plastic contains a restricted phthalate ester plasticizer, contains an internal lubricant that is metabolized to the GHB date-rape drug, contains specific banned brominated flame retardants, or produces excess volatile organic compound (VOC) emissions. We have the analytical methodologies to address each of these issues.
Fillers are an additional important component of compounded polymer materials. Mineral fillers, carbon black, and various types of reinforcing fillers are used to enhance the physical properties of polymers. Scanning electron microscopy coupled with energy dispersive spectroscopy is used to determine the type of filler that is incorporated into the plastic. Some fillers are so tiny, or have a very specific and distinctive structure, that ultra-microtome techniques coupled with transmission electron microscopy is required. Or, the fillers may be large enough that high resolution digital optical microscopy is the appropriate characterization method. The microscopy methods also provide information related to filler particle shapes and aspect ratio. Glass fiber length and diameter, talc platelet diameters, calcium carbonate particle size, and carbon black structure are evaluated using the microscopy methods. Thermogravimetric analysis is often the appropriate method for determining the amount of filler that is present in a compounded polymer material.