Polymers have excellent chemical resistance, strength, and elasticity, but such properties can hinder their chemical analysis. The quality control techniques used for measuring additive levels in polymers may vary, depending on the physical and chemical properties of them. Even slight differences in the process parameters can cause large variations in the characteristics of polymer products in the polymerization process. The polymer properties and the processing parameters must be determined and adjusted through rapid feedback. NIR spectroscopy offers structural and kinetic data in real time and so can be used for such applications.
NIR spectroscopy can be used on nearly all types of polymers, including solid powders, solutions, melts, and emulsions. NIR spectrometer systems integrated with fiber probes bring a new dimension to process monitoring in polymer manufacturing plants. Fiber probes can be utilized in adverse operating environments, whilst the analysis computer and spectrometer can be kept safely in a process monitoring room. For contact and non-contact measurement, many NIR optical probes are available, ranging from immersion probes and fiber optic transmission pair probes to reflectance probes. Probes that are commercially available in the market can be used in most polymer process monitoring applications.
There are several types of NIR probes:
- micro interactance reflectance probe;
- micro interactance immersion probe;
- micro transmission probe pair with lenses and spacers;
- micro interactance reflectance probe with purge on collection tip;
- optimized 45º micro reflectance probe;
- non-contact probe.
Fiber cables are often used to transfer the NIR light from the instrument to the processing probe. When the light scattering characteristics of the process sample increases, the number of fibers integrated into the fiber optic bundle should also be increased. This helps maintain the analytical performance of the instrument.
NIR spectroscopy is a key analytical tool that can be used for optimizing process control as well as product quality and could help deliver better and more cost-effective products to the market. In-line high-pressure and high-temperature fiber probes, fiber optics, and analytical instruments facilitate the use of spectroscopic methods for tracking the processes of polymer production in industrial setups.
Optromix offers high-performance, high-quality specialty optical fiber cables that cover the range from UV (180 nm) to the mid-infrared (18 μm) for different applications such as environmental sensing, space and military applications, and industrial manufacturing.