The infrared spectroscopic analysis of black polypropylene (PP) polymers with varying electrical conductivities shows that increasing conductivity leads to a pronounced attenuation or complete masking of characteristic infrared absorption bands. This behavior arises from interactions between the incident electromagnetic radiation and free charge carriers, thereby limiting the applicability of Fourier-transform infrared (FTIR) spectroscopy for reliable material identification. Comparable limitations may also occur in non-black polymers that exhibit sufficiently high electrical conductivity. Theoretical modeling and experimental measurements of the samples are presented.
Citation: Wolfgang Becker, Wenka Schweikert, Stephan Müller, Patrick Weiss. Spectral IR reflectance analysis of black polymer samples with different electrical conductivities. Important results concerning plastics recycling[J]. Clean Technologies and Recycling, 2026, 6(2): 122-138. doi: 10.3934/ctr.2026006
The infrared spectroscopic analysis of black polypropylene (PP) polymers with varying electrical conductivities shows that increasing conductivity leads to a pronounced attenuation or complete masking of characteristic infrared absorption bands. This behavior arises from interactions between the incident electromagnetic radiation and free charge carriers, thereby limiting the applicability of Fourier-transform infrared (FTIR) spectroscopy for reliable material identification. Comparable limitations may also occur in non-black polymers that exhibit sufficiently high electrical conductivity. Theoretical modeling and experimental measurements of the samples are presented.
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Wolfgang Becker, Wenka Schweikert, Stephan Müller, Patrick Weiss. Spectral IR reflectance analysis of black polymer samples with different electrical conductivities. Important results concerning plastics recycling[J]. Clean Technologies and Recycling, 2026, 6(2): 122-138. doi: 10.3934/ctr.2026006
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