GB/T 24135-2022Rubber-or plastics-coated fabrics - Accelerated-ageing tests (English PDF)

5.1 of this Edition);

--- Change the air oven in Method-A, Method-B and Method-D to a high temperature test

chamber; and change the air oven in Method-C is to a damp heat test chamber (see 4.2.1,

5.2.1, 6.2.1 and 7.2.3 of this Edition; 3.2.1, 4.2.1, 5.2.1 and 6.2.3 of the 2009 Edition);

--- Increase the accuracy provisions of the thermometer (see 4.2.2, 5.2.2 and 6.2.2 of this

Edition);

--- Add "ruler" and "dryer" instrument devices (see 4.2.4 and 4.2.5 of this Edition);

--- Change the cooling method of the test in Method-A to cooling in a desiccator (see 4.5 of

this Edition; 3.5 of the 2009 Edition);

--- Change the content of the NOTE to the main text (see 4.5, 5.3 and 6.3 of this Edition;

3.5, 4.3 and 5.3 of the 2009 Edition);

--- Change the characters in the formula, using "QAT, QAC" to replace "rhoAT, rhoAC" (see 4.6 of

this Edition, 3.6 of the 2009 Edition).

This Document equivalently adopts ISO 1419:2018 Rubber- or Plastics-Coated Fabrics -

Accelerated-Aging Tests.

The following minimal editorial modifications have been made to this Document:

--- Add a NOTE to explain the purpose of the prepared specimen (see 4.3 of this Document);

--- Add a NOTE to explain the method of obtaining the mass per unit area QAT of the tested

material in the formula (see 4.6 of this Document).

Please note some contents of this Document may involve patents. The issuing agency of this

Document shall not assume the responsibility to identify these patents.

Rubber- or Plastics-Coated Fabrics - Accelerated-Aging Tests

WARNING: Persons using this document should be familiar with normal laboratory

practice. This document does not purport to address all of the safety problems, if any,

associated with its use. It is the responsibility of the user to establish appropriate safety

and health practices and to ensure compliance with any national regulatory conditions.

4.2.3 Balance, capable of weighing to an accuracy of 1 mg.

4.2.4 Ruler or other length-measuring device, of accuracy +/-0.5 mm.

4.2.5 Desiccator for cooling the specimens after removal from the test chamber.

4.3 Preparation of test pieces

Cut out six test pieces, each measuring 100 cm2 +/- 1 cm2, selected so that, as far as possible,

they are evenly spaced across the Sample, but not within 50 mm of a selvedge.

NOTE: Among the 6 specimens, 3 specimens measure the mass m1 of the specimen before aging and the

mass per unit area of the coating layer, which are used to obtain the values of QAT and QAC. The other 3

specimens are used for ageing test, measure the specimen mass m2 after the aging. Substitute the m1, m2

of the 3 specimens and the obtained QAT and QAC values into the formula to calculate the test results.

4.4 Conditioning and determination of mass

Condition the test pieces in atmosphere A, B or C as defined in ISO 2231. Determine and record

the mass m1 of each test piece to an accuracy of 1 mg in accordance with ISO 2286-1. Determine

the mass per unit area QAC of the coating of three test pieces in accordance with ISO 2286-2.

4.5 Procedure

Select three of the conditioned test pieces as per 4.4, making a note of the conditioned mass of

each (m1). Pre-heat the test chamber to the test temperature of 100 °C +/- 1 °C. Place the test

pieces in the test chamber so that they are free from strain and exposed to the free passage of

air on both sides. Remove the test pieces from the test chamber after 16 h and immediately put

it into the dryer for cooling.

Re-condition the test pieces in accordance with 4.4 and determine and record the mass m2 of

each to an accuracy of 1 mg in accordance with ISO 2286-2.

If test pieces conditioned as specified in 4.4 after preparation approach equilibrium from the

wet side of the hysteresis curve, this may result in an apparent inaccuracy due to the hysteresis

loss caused by reconditioning from the dry side of the hysteresis curve after ageing. This effect

will be more marked with highly hygroscopic substrates, and in such cases, it is advisable to

pre-condition the test pieces in a dry atmosphere, i.e., one having a relative humidity less than

4.6 Expression of results

Calculate the loss in mass of each test piece, expressed as a percentage of the coating mass,

using the Formula (1):

......