FT-IR Imaging System And Thermal Analysis Of Characterization Of Recycled Plastic PE Composition

Recycled plastic is from waste plastic, it covers sorts of harmful substances. These substances may sourse from the residue of original pack, the additives which were used by all sorts of technologys or the degradation of polymer or additives. With the development of recycled plastic industry, at present, the blind spots of recycled plastic in supervision are still exist, In this context, the identification of recycled plastic, especially the methods of characterization of its composition have been discussed which is vital significance.Three kinds of original polyethylene (PE), three kinds of PE recycled plastic and four kinds of PE recycled plastic bottles have been discuessed in this paper. Using infrared spectrometry and thermal analysis (DSC and TG) methods, we contrast and analyse three kinds of original PE and three kinds of PE recycled plastics, a kind of instrument identification method of PE and PE recycled was established preliminarily; In the concept of characterization of PE recycled plastic’s components, we used infrared image system and thermal to test and analyse all samples respectively in addition to conventional methods, for example, IR and UV. The infrared image system is applied in characterizing recycled plastics’ components,which was no reported at home and abroad. It is a new exploration. The data process method of infrared image system was also discussed in the paper. The analys of chemimap layer handling of total absorption graph, which obtained by infrared image system under transmission mode approach for the experiment testings in this paper.Comprehensive test show that the three kinds of recycled PE contain stearic acid salt (recycled PE-1also contains a few PP). The analysis of IR spectrum diagram and thermal analysis of recycled PE-1and recycled PE-Q28are different. The explaination of which is that firstly the contents (stearic acid salt) is trace components, secondly it is diluted by other substances. So the hot melt peak is not detected in thermal analysis, but appeares weak characteristics absorption peaks in its infrared spectrum diagram; The main component of four kinds of recycled plastic bottles are HDPE and PP. Quantitatively analyse was conducted by simulation of stearic acid salt and HDPE/PP blends. By infrared image system the components distribution of PE recycled plastics was analyzed. The results were coincided with those of IR and thermal analysis, which further verified compositions in PE recycled plastics.As a new characterization technique of recycled plastic, we believe Infrared Image System will have greater value in use and application potential.