ASTM D 2238 : 1992 : R2004

CONTAINED IN VOL. 08.01, 2015 Describes measurement by infrared absorption spectrophotometry of the 1378.4 cm[-1] band in polyethylene due to methyl groups.

1.1 These test methods cover measurement by infrared absorption spectrophotometry of the 1378.4-cm¹ (7.255-m) band in polyethylene due to methyl groups. (1, 2, 4-7) Two test methods are covered:

1.1.1 Test Method A uses compensation with a standard sample film or wedge of known methyl content.

1.1.2 Test Method B uses compensation with a wedge of polymethylene or a polyethylene of known low methyl content.

1.2 These test methods are applicable to polyethylenes of Types I (density 910 to 925 kg/m³), II (density 926 to 940), and III (density 941 to 965).

Note 1—For determination of density, see Specifications D 1248.

Note 2—In cases of Type III polyethylene with densities greater than 0.950 g/cm³, different results are obtained with the two test methods.

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

1.4 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. Specific hazards statements are given in Section 7.

Note 3—There is no similar or equivalent ISO standard covering the subject matter of these test methods.