DOI: 10.5281/zenodo.13814805
title: PP-recyclate characterization after different sampling and recycling strategies-MFR

description: PP-recyclates characterization after different sampling and recycling strategies – MFR data

Authors: A. Martínez García, A. Ibáñez García, M.A. León CabezasInnovative Materials and Manufacturing Area, AIJU, Avda. de la Industria, 23 03440 Ibi (Alicante), Spain Contact Informationemail: sunymartinez@aiju.estel: +34 965554475

This dataset contains raw MFR data of PP-recyclates from different recycling strategies following different sampling strategies.

The purpose of this analysis is to evaluate the efficiency of the different recycling strategies and the quality of the resulting recyclates in combination with other analysis techniques.

Recycling strategies followed: 

1) Purification of PP-rich post-consumer waste using supercritical CO2 (scCO2). scCO2 does not alter particle size or shape. The waste material was subjected to scCO2 treatment in two ways. The first method involved directly treating the flake material, which was subsequently ground. These samples are labelled CO-PP03RE-SC01GR. The second approach aimed to investigate whether cleaning efficiency depends on particle size. The flakes were ground first, and scCO2 was then applied to the particles, resulting in a sample identified as CO-PP03RE-GRSC01. Homogenous powder was obtained in both cases and five samples were analysed following the MFR.  For the sample preparation, the flakes of the waste were ground using a ring sieve mill (ZM 300, Retsch, Haan, Germany). 

Data from this approach are given in: PP recyclates after sc-CO2 recycling-MFR.xlsx

 2) Purification of PP-rich post-consumer waste using solvent-based CreaSolv® process, developed by Fraunhofer IVV. The solvent-based recycling process results in more homogeneous recyclates by dissolving the entire sample, and selectively precipitating the desired purified polymer, with the potential of removal of unwanted components. The waste material was subjected to solvent-based recycling treatment in two ways. The first method includes additional purification with a solid-liquid separation step, referred to as CO-PP03RE-CS+SL. 

The second method is without this additional purification, labeled as CO-PP03RE-CS-SL. Homogenous powder was obtained through solvent-based recycling process and five samples were analysed directly following the parallel plate rheology protocol. 

Data from this approach are given in: PP recyclates after solvent-based recycling-MFR.xlsx 

3) Purification of PP-rich post-consumer waste after upcycling and compounded by mechanical reprocessing.The waste material was compounded after the reformulation with additives to enhance specific properties.The material was subjected to compounding by means of remelting-restabilization, labeled as CO-PP03RE-CO.Homogenous pellets were obtained through compounding recycling process.

Data from this approach are given in: PP recyclates after upcycling-MFR.xlsx

Reference samples: PP-rich waste flakes were ground using a ring sieve mill to a particles size below 750 µm. Five samples were analyzed. 

The nomenclature followed is presented in the Table below:

Recyclate Nomenclature                       DescriptionCO-PP03RE-GR                       PP Recyclate after cryogenic grinding (reference material)CO-PP03RE-CO (Brug)            PP Recyclate after compounding with Bruggolen CO-PP03RE-GRSC01               PP Recyclate after cryogenic grinding and scCO2CO-PP03RE-SC01GR               PP Recyclate after scCO2 and cryogenic grindingCO-PP03RE-CR-SL                  PP Recyclate after Creasolv without solid-liquid separationCO-PP03RE-CR+SL                 PP Recyclate after Creasolv with solid-liquid separation