Significance and Use

General Utility :

It is useful to verify catalyst levels in a resin blend or a polyurethane system.

This practice is suitable for research, quality control, specification testing, and process control.

Limitations :

Several of the measured parameters are subjective. Therefore, operator-to-operator variability and lab-to-lab variability can be much higher than that of a single operator.

The variability of this practice is dependent on the consistency of mixing of the reactants.

The estimation of precision in this practice is based on typical formulations for rigid and flexible foams. Formulations with faster reaction times will likely have greater variability, particularly cream time (initiation time). Formulations with slower reaction times will likely have greater variability in the measurement of free rise time.

It is possible that low-level (ppm, ppb) ingredient contamination will not be detectable using this practice. Confirmation of such contamination will potentially require large-scale (~ 20 litres) tests and is out of the scope of this practice.

1. Scope

1.1 This practice covers the determination of cream time (initiation time), top of cup time, free rise time, free rise height, string gel time (pull time), tack free time, settle back, and free rise density of polyurethane foam formulations using a cup foam test.

1.2 Typical definitions, terms, and techniques are described; including procedures for mixing and transferring samples to the foaming container; and data gathering and evaluation. However, agreement between the customer and the testing laboratory for all these items must be obtained prior to use.

1.3 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

D883 Terminology Relating to Plastics

E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

Keywords

cream time; cup test; foam testing; formulated polyol; free rise density; free rise height; free rise time; initiation time; isocyanate; polyurethane; pull time; raw material; resin blend; settle back; sigh back; sink back; string gel time; tack free time; top of cup time;

ICS Code

ICS Number Code 83.080.10 (Thermosetting materials)

DOI: 10.1520/D7487-08

ASTM International is a member of CrossRef.

ASTM D7487