%0 Journal Article
%T Improved High Performance Recycling of Polymers by Means of Bi-Exponential  Analysis of Their Fluorescence Lifetimes
%A Heinz Langhals
%A Dominik Zgela
%A Thorben Schl¨ącker
%J Green and Sustainable Chemistry
%P 92-100
%@ 2160-696X
%D 2015
%I Scientific Research Publishing
%R 10.4236/gsc.2015.52012
%X Technical polymers could be identified by means of their remarkably strong auto fluorescence. The mono-exponentially obtained time constants of fluorescence decay were applied for a rough assignment of the polymeric materials whereas bi-exponential analysis allowed a fine classification such as for special batches and for preceding contaminations. Chemically similar materials such as LDPE (low-density polyethylene), HDPE (high-density polyethylene) and UHDPE (ultrahigh-density polyethylene) could be as well identified as contaminations of mineral oil in PET (polyethylene terephthalate). Furthermore, the fluorescence spectra could be characterized by means of five Gaussian functions in the visible allowing a redundant assignment to the fluorescence lifetimes. Thus, efficient sorting of polymers was possible for high performance recycling.
%K Recycling
%K Polymers
%K Fluorescence Decay
%K Fluorescence Spectroscopy
%K Gaussian
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=56320