ASTM D789-15
Standard Test Methods for Determination of Solution Viscosities of Polyamide (PA)

Standard No.

ASTM D789-15

Release Date

2015

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM D789-18

Latest

ASTM D789-19

Scope

4.1 These test methods are intended for use as control and acceptance tests. They are also applicable in the partial evaluation of materials for specific end uses and as a means for detecting changes in materials due to specific deteriorating causes.

4.2 The steps involved in running this method are:

4.2.1 Calibration of the viscometers,

4.2.2 Preparation of solutions,

4.2.3 Determination of efflux time,

4.2.4 Calculation of relative viscosity (which requires the following),

4.2.4.1 Determining the density of the polymer/formic acid solution, and

4.2.4.2 Determining the absolute viscosity of the formic acid used.

4.3 Viscosity for groups 03, 04, and 05 (PA11, PA12, and PA6,12) in Classification System D6779 shall be measured using solvents other than formic acid. Relative viscosities for Groups 03 and 04 shall be measured using 0.5 g of polymer dissolved in 99.5 g of m-cresol at 25.0 ± 0.1°C in a Cannon-Fenske No. 200 viscometer. Inherent viscosity of Group 05 shall be measured using 0.5 g of polymer dissolved in 100 mL of m-cresol at 25.0 ± 0.1°C in a Cannon-Fenske No. 200 viscometer. The inherent viscosity is calculated as follows:

where:
ts	=	average efflux time for sample solution,
tc	=	average efflux time for solvent, and
C	=	concentration in g/100 mL

1.1 These test methods cover the determination of solution viscosities as they apply to polyamide (PA).

1.2 The values stated in SI units are to be regarded as standard. The values given in brackets are for information only.

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 1: This standard and ISO8201;307 addre......

ASTM D789-15 Referenced Document

• ASTM D446 Standard Specifications and Operating Instructions for Glass Capillary Kinematic Viscometers
• ASTM D6779 Standard Classification System for and Basis of Specification for Polyamide Molding and Extrusion Materials (PA)
• ASTM D883 Standard Terminology Relating to Plastics
• ISO 307 Plastics — Polyamides — Determination of viscosity number
• ISO/IEC 17025 General requirements for the competence of testing and calibration laboratories [Standard in French]

ASTM D789-15 history

• 2019 ASTM D789-19 Standard Test Method for Determination of Relative Viscosity of Concentrated Polyamide (PA) Solutions
• 2018 ASTM D789-18 Standard Test Method for Determination of Relative Viscosity of Concentrated Polyamide (PA) Solutions
• 2015 ASTM D789-15 Standard Test Methods for Determination of Solution Viscosities of Polyamide (PA)
• 2007 ASTM D789-07e1 Standard Test Methods for Determination of Solution Viscosities of Polyamide (PA)
• 2007 ASTM D789-07 Standard Test Methods for Determination of Solution Viscosities of Polyamide (PA)
• 2006 ASTM D789-06a Standard Test Methods for Determination of Solution Viscosities of Polyamide (PA)
• 2006 ASTM D789-06 Standard Test Methods for Determination of Relative Viscosity of Polyamide (PA)
• 2005 ASTM D789-05 Standard Test Methods for Determination of Relative Viscosity of Polyamide (PA) ^1,2
• 2004 ASTM D789-04 Standard Test Method for Determination of Relative Viscosity of Polyamide (PA)
• 1998 ASTM D789-98 Standard Test Methods for Determination of Relative Viscosity and Moisture Content of Polyamide (PA)