Significance and Use

Recycled plastic materials may contain incompatible plastic or other undesirable contaminants that could affect the processing or quality, or both, of the plastic prepared for reuse. Techniques to separate and identify incompatible plastics, moisture, chemicals, or original product residues, and solid contaminants such as metals, paper, glass, and wood are essential to the processing of recycled plastic materials.

This guide lists existing ASTM and ISO methods plus currently practiced industrial techniques for identification and classification of contaminants in recycled plastics flake or pellets.

1. Scope

1.1 This guide is intended to provide information on available methods for the separation and classification of contaminants such as moisture, incompatible polymers, metals, adhesives, glass, paper, wood, chemicals, and original-product residues in recycled plastic flakes or pellets. Although no specific methods for identification or characterization of foam products are included, foam products are not excluded from this guide. The methods presented apply to post-consumer plastics.

1.2 For specific procedures existing as ASTM test methods, this guide only lists the appropriate reference. Where no current ASTM standard exists, however, this guide gives procedures for the separation or identification, or both, of specific contaminants. Appendix X1 lists the tests and the specific contaminant addressed by each procedure.

1.3 This guide does not include procedures to quantify the contaminants unless this information is available in referenced ASTM standards.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Note 1There is no known ISO equivalent to this standard.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D789 Test Methods for Determination of Solution Viscosities of Polyamide (PA)

D792 Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement

D883 Terminology Relating to Plastics

D1003 Test Method for Haze and Luminous Transmittance of Transparent Plastics

D1193 Specification for Reagent Water

D1238 Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer

D1457 Specification for Polytetrafluoroethylene (Ptfe) Molding and Extrusion Materials

D1505 Test Method for Density of Plastics by the Density-Gradient Technique

D1898 Practice for Sampling of Plastics

D1925 Test Method for Yellowness Index of Plastics

D3418 Test Method for Transition Temperatures and Enthalpies of Fusion and Crystallization of Polymers by Differential Scanning Calorimetry

D4019 Test Method for Moisture in Plastics by Coulometric Regeneration of Phosphorus Pentoxide

D5033 Guide for Development of ASTM Standards Relating to Recycling and Use of Recycled Plastics

D5227 Test Method for Measurement of Hexane Extractable Content of Polyolefins

E169 Practices for General Techniques of Ultraviolet-Visible Quantitative Analysis

E355 Practice for Gas Chromatography Terms and Relationships

E682 Practice for Liquid Chromatography Terms and Relationships

E794 Test Method for Melting And Crystallization Temperatures By Thermal Analysis

E1252 Practice for General Techniques for Obtaining Infrared Spectra for Qualitative Analysis

ISO Standards

Keywords

compression moldings; contaminants; density separations; extrusion; post-consumer plastics; recycled plastics; visual inspection; Chlorinated polymer contamination; Compression-molded plastic specimens; Contamination--plastics; Density separations; Extrusion compounds (plastic); Extrusion melt/flow test; Post-consumer plastics; Recycled plastics; Solvent extraction; Stain 5 test; Visual examination--plastics;

ICS Code

ICS Number Code 83.080.01 (Plastics in general)

DOI: 10.1520/D5577-94R10E01

ASTM International is a member of CrossRef.

ASTM D5577