Significance and Use

This test method may be applied to all papers made from unmodified cellulose, as used in transformer, cable, or capacitor manufacture. It applies to new or aged papers. For information, Appendix X1 shows an example of statistical distribution of values for new papers intended for the insulation of transformers, together with information relative to cable and capacitor papers. Nevertheless, where evaluating the decomposition stage of aged papers, take care to use, as a reference, the value of the new paper of the very same origin; of new papers being a function, among other factors, of their specific gravity and of their manufacturing process.

This test method can also be used for the determination of the intrinsic viscosity of solutions of chemically modified papers, provided that these dissolve completely in the selection solvent. This test method should be used with caution when it is applied to papers with mineral fillers.

1. Scope

1.1 This test method describes a standard procedure for determining the average viscometric degree of polymerization (abbreviated ) of new or aged electrical papers. The determination is made by measuring the intrinsic viscosity of a solution of the paper in an appropriate solvent.

1.2 The degree of polymerization (or the degree of condensation) of a particular cellulose molecule is the number of anhydro- ? -glucose monomers, C ₆ H ₁₀ O ₅ , in the cellulose molecule. Within a sample of paper, not all the cellulose molecules have the same degree of polymerization so that the mean value measured by viscometric methods is not necessarily the same as that which may be obtained by other methods.

1.3 This standard may involve hazardous materials, operations, and equipment. 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 to determine the applicability of regulatory limitations prior to use. See Section 9

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

D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)

D1711 Terminology Relating to Electrical Insulation

Other Document

Keywords

aging; board; cellulose; cupriethylene-diamine; degree of polymerization; paper; pressboard; viscometry
; Aging board; Average viscometric degree of polymerization (DP v ); Cellulose and cellulose derivatives; Cupriethylene-diamine; Electrical insulating paper/paperboard; Paper; Polymerization; Polymers (electrical insulation applications); Pressboard (electrical insulating); Scrub resistance; Viscosity--intrinsic;

ICS Code

ICS Number Code 29.035.10 (Paper and board insulating materials)

DOI: 10.1520/D4243-99R09

ASTM International is a member of CrossRef.

ASTM D4243