open access

https://hdl.handle.net/2115/77655

Determination of the absolute molar mass of acetylated eucalyptus kraft lignin by two types of size-exclusion chromatography combined with multi-angle laser light-scattering detectors

英語

multi-angle laser light scattering (MALLS)

2019-04-24

Walter de Gruyter

Holzforschung

73(4)

363-369

The molar mass (MM) and polydispersity indices (PDI) of acetylated hardwood kraft lignin (Ac-HWKL) and Ac-HWKL fractions were measured by size-exclusion chromatography with multi-angle laser light scattering (SEC-MALLS). The detectors worked at LL₆₅₈ ₙₘ and LL₇₈₅ₙₘ. The MM of Ac-HWKL measured at 785 nm was much smaller than that measured at 658 nm. The number-average (Mn) and weight-average (Mw) molar masses of Ac-HWKL determined at 785 nm were approximately 6.2 and 6.5 times larger, respectively, than the values estimated using a conventional calibration curve created with authentic polystyrene standards in tetrahydrofuran (THF). Based on the Mw of Ac-HWKL fractions, the Mark-Houwink-Sakurada equation for Ac-HWKL was established to be [η]/ml g⁻¹ = 0.320 M⁰∙²⁴ in THF and [η]/ml g⁻¹ = 0.142 M⁰∙²⁶ in dimethyl sulfoxide (DMSO). These results demonstrate that Ac-HWKL has a more compact structure in an organic solvent than polystyrene.

学術雑誌論文

Version of Record

0018-3830

1437-434X

AA00664822