Polymers, Plastics, and Adhesives
Raman Imaging and Microscopy Polymer Applications
Cure degree of resin and its distribution
Photopolymerization, initiated by light, swiftly transforms liquid resin into solid polymer, ensuring precise curing and high resolution. Raman spectroscopy monitors this process in real-time, tracking molecular changes in the resin, quantifying monomers and initiators, essential for optimizing material properties. Its non-destructive nature enables repeated measurements, providing valuable insights into evolving molecular composition.
The Raman spectra of the resin before UV irradiation and after 115 and 205 minutes of irradiation were examined. Peaks corresponding to the polymerization initiator (1598 cm-1) and monomers (1640 cm-1) were clearly identified. With increasing UV irradiation time, there was a noticeable decrease in the intensity of the monomer peak at 1640 cm-1, indicating the progression of polymerization.
The degree of resin curing was determined by the intensity ratio of peaks at 1640 cm-1 (monomers) and 1598 cm-1 (initiator), showing a corresponding increase with extended UV irradiation time.
Analysis of paint color variations
Analyzing the paint layers on cans is crucial for ensuring product quality, consistency, and regulatory compliance. Understanding the composition and distribution of paint layers helps manufacturers optimize processes for consistent quality, improve durability, and comply with safety standards.
Raman imaging, with its ability to reveal composition and distribution variations, is a valuable tool for achieving these goals.In the example given, the surface of a beverage can was analyzed using Raman imaging. 785nm excitation is used to avoid fluorescence emission from the sample. Green color shows substrate. Blue and red color shows the unevenness distribution of two coating compounds.
