BS EN ISO 16014-5:2019
Plastics. Determination of average molecular weight and molecular weight distribution of polymers using size-exclusion chromatography Light-scattering method
Označení normy: | BS EN ISO 16014-5:2019 |
Počet stran: | 34 |
Vydáno: | 2019-06-18 |
ISBN: | 978 0 580 52251 2 |
Status: | Standard |
BS EN ISO 16014-5:2019
This standard BS EN ISO 16014-5:2019 Plastics. Determination of average molecular weight and molecular weight distribution of polymers using size-exclusion chromatography is classified in these ICS categories:
- 83.080.01 Plastics in general
This document specifies a general method for determining the average molecular weight and the molecular weight distribution of polymers using SEC-LS, i.e. size-exclusion chromatography coupled with light-scattering detection. The average molecular weight and the molecular weight distribution are calculated from molecular weight data and weight concentrations determined continuously with elution time. The molecular weight at each elution time is determined absolutely by combining a light-scattering detector with a concentration-sensitive detector. Therefore, SEC-LS is classified as an absolute method.
This method is applicable to linear homopolymers and to nonlinear homopolymers such as branched, star-shaped, comb-like, stereo-regular and stereo-irregular polymers. It can also be applied to heterophasic copolymers whose molecular composition cannot vary. However, SEC-LS is not applicable to block, graft or heterophasic copolymers whose molecular composition can vary. And the methods are applicable to molecular weights ranging from that of the monomer to 3 000 000, but are not intended for samples that contain > 30 % of components having a molecular weight < 1 000.
This document specifies a general method for determining the average molecular weight and the molecular weight distribution of polymers using SEC-LS, i.e. size-exclusion chromatography coupled with light-scattering detection. The average molecular weight and the molecular weight distribution are calculated from molecular weight data and weight concentrations determined continuously with elution time. The molecular weight at each elution time is determined absolutely by combining a light-scattering detector with a concentration-sensitive detector. Therefore, SEC-LS is classified as an absolute method.
This method is applicable to linear homopolymers and to nonlinear homopolymers such as branched, star-shaped, comb-like, stereo-regular and stereo-irregular polymers. It can also be applied to heterophasic copolymers whose molecular composition cannot vary. However, SEC-LS is not applicable to block, graft or heterophasic copolymers whose molecular composition can vary. And the methods are applicable to molecular weights ranging from that of the monomer to 3 000 000, but are not intended for samples that contain > 30 % of components having a molecular weight < 1 000.