Tear Resistance and Abrasion Resistance Testing

Polyhedron – Elastomer Testing
Polyhedron Laboratories performs physical testing according to ASTM standards, such as Adhesion to a Flexible Substrate (ASTM D413), Adhesion to a Rigid Substrate (ASTM D429), % Ash (ASTM D297 Part 34), % Carbon Black (ASTM 297), Deterioration in an Air Oven (ASTM D573), Chemical Resistance (Change in Hardness and Volume/70 hours), and Oil Resistance (70 hours) (ASTM 471), Compression Set Method B (ASTM D395), Compression Deflection (ASTM D575), Hardness (ISO) (ASTM D1415), Hardness (Durometer) (ASTM D2240), Heat Aging 70 hours/250 Degrees Fahrenheit (ASTM D573), Change in Hardness (ASTM D865), Identification by Infrared (ASTM D3677), Tear Resistance (ASTM D624), Tensile, Elongation and Modulus Properties (ASTM D412), and Total Extractables (ASTM D297, Part 20).

All ASTM standard descriptions below are paraphrased from the ASTM website (www.astem.org). Due to copyright restrictions, Polyhedron Laboratories cannot make available copies of standards. Standards can be found and are available at www.astem.org.

Adhesion to a Flexible Substrate
ASTM D413-98e1 - Standard Test Methods for Rubber Property—Adhesion to Flexible Substrate - These test procedures deal with the determination of the adhesion strength between plies of fabric bonded with rubber or the adhesion of the rubber layer in items made from rubber, then attached to other material. These test methods apply when the adhered surfaces are uniformly circular or approximately plane as in hose, belting, rubber-covered sheet metal, or tire carcasses.

Adhesion to a Rigid Substrate
ASTM D429-03 Standard Test Methods for Rubber Property—Adhesion to Rigid Substrates - These test procedures deal with routines for testing the static adhesional strength of rubber to rigid materials (in most cases, metals). Procedure A is the method for a rubber part assembled in between two parallel metal plates. Procedure B is the routine for perpendicular stripping of a test-rubber part assembled to a single metal plate. Procedure C is used to measure the adhesion of rubber to metal with a conical sample. Procedure D involves the adhesion test post-vulcanization (PV) bonding of rubber to metal. Procedure E is the routine for perpendicular stripping of a test rubber tank lining assembled to a single metal plate. Procedure F involves a rubber part assembled in between two parallel convex-shaped metal plates. Procedure G is used to measure bond durability for rubber-to-metal bonded components with a double shear cylindrical sample. Procedure H is used in measuring of bond durability for rubber-to-metal bonded parts with a quadruple shear cylinder sample.

% Ash, % Carbon Black
ASTM D297-93e2 - Standard Test Methods for Rubber Products-Chemical Analysis - These test procedures deal with the quantitative and qualitative analysis (including ash analysis and fillers analysis, including % Carbon Black) of the composition of rubber products. Many of these test routines can be used for the analysis of synthetic and natural crude rubbers.

Deterioration in an Air Oven
ASTM D573-04 - Standard Test Method for Rubber—Deterioration in an Air Oven – This test procedure outlines a method to determine the influence of elevated temperature on the physical properties of vulcanized rubber. This test routine can be used to evaluate rubber compounds on a laboratory comparison basis.

Chemical Resistance (Change in Hardness and Volume/70 hours), and Oil Resistance (70 hours)

ASTM D471-98e2 - Standard Test Method for Rubber Property-Effect of Liquids - This test procedure deals with the required methods to evaluate the comparative ability of rubber-like and rubber compositions to withstand the effect of liquids. It is designed for testing samples cut from fabric coated with vulcanized rubber, samples of vulcanized rubber cut from standard sheets, or finished articles of commerce.

Compression Set Method B
ASTM D395-03 Standard Test Methods for Rubber Property—Compression Set - These test procedures outline the testing of rubber to be used in applications where the rubber will be subjected to compressive stresses in liquid media or air. The test method applies to the rubber used in seals, vibration dampers, and machinery mountings. Method B involves the testing involving compression set under constant force in air.

Compression Deflection
ASTM D575-91 - Standard Test Methods for Rubber Properties in Compression - These test procedures outline the test methods for determining the compression-deflection characteristics of rubber compounds other than those usually classified as sponge rubber and hard rubber.

Hardness (ISO)
ACTIVE STANDARD: D1415-05 Standard Test Method for Rubber Property—International Hardness - This test procedure deals with the method for measuring the hardness of rubber. The hardness is obtained by the difference in penetration depth of a specified dimension ball under two conditions of contact with the rubber – first, with a small initial force, and second, with a much larger final force. The differential penetration is measured at a specific time and then converted to a hardness scale value.

Hardness (Durometer)
ASTM D2240-05 - Standard Test Method for Rubber Property—Durometer Hardness - This test procedure outlines twelve types of rubber hardness measurement devices known as durometers: Types A and D. The procedure for determining indentation hardness of substances classified as vulcanized (thermoset) rubber, thermoplastic elastomers, cellular materials, elastomeric materials, gel-like materials, and some plastics are also described.

ASTM D865-99 - Standard Test Method for Rubber-Deterioration by Heating in Air (Test Tube Enclosure) - This test procedure outlines a method to determine the deterioration induced by heating rubber samples in individual test tube enclosures with circulating air. This isolation prevents cross contamination of compounds due to loss of volatile materials (for example, antioxidants) and their subsequent migration into other rubber compounds. The absorption of such volatile materials can influence the rate of degradation of rubber compounds.

Identification by Infrared
ASTM D3677-00 - Standard Test Methods for Rubber--Identification by Infrared Spectrophotometry - These test procedures are based on the infrared examination of films and pyrolysis products (pyrolyzates) can be used for rubber identification. Additionally, these test routines apply to rubbers in the raw state and, when compounded, both in the uncured and cured state.

Tear Resistance
ASTM D624-00e1 - Standard Test Method for Tear Strength of Conventional Vulcanized Rubber and Thermoplastic Elastomers - This test procedure outlines the methods for measuring a property of thermoplastic elastomers and conventional vulcanized thermoset rubber referred to as tear strength.

Tensile, Elongation and Modulus Properties
ASTM D412-98a-e1 - Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers—Tension - These test procedures deal with methods used to evaluate the tensile (tension) properties of thermoplastic elastomers and vulcanized thermoset rubbers. There are two procedures – Test Procedure A covers dumbbell and straight section samples, while Test Procedure B covers cut ring samples.

ASTM D297 (Part 20)- Standard Test Methods for Rubber Products-Chemical Analysis – These test procedures outline the quantitative and qualitative analysis of rubber products. Many of these test methods apply to the analysis of synthetic and natural rubbers.