Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Collections
Magazine articles
Industry leaders: jukka harmala leads stora enso into new global age, TAPPI JOURNAL, May 2000, Vol. 83(5)
Industry leaders: jukka harmala leads stora enso into new global age, TAPPI JOURNAL, May 2000, Vol. 83(5)
Magazine articles
A personal mount st. helens experience, TAPPI JOURNAL, May 2000, Vol. 83(5)
A personal mount st. helens experience, TAPPI JOURNAL, May 2000, Vol. 83(5)
Magazine articles
Energy: recovering capital and cutting costs, TAPPI JOURNAL, November 2000, Vol. 83(11)
Energy: recovering capital and cutting costs, TAPPI JOURNAL, November 2000, Vol. 83(11)
Magazine articles
What's new with tappi test methods?, TAPPI JOURNAL, September 2000, Vol. 83(9)
What's new with tappi test methods?, TAPPI JOURNAL, September 2000, Vol. 83(9)
Magazine articles
Environmental issues continue to be a major industry concern, TAPPI JOURNAL, September 2000, Vol. 83(9)
Environmental issues continue to be a major industry concern, TAPPI JOURNAL, September 2000, Vol. 83(9)
Magazine articles
Taiwan holds first symposium on environmentally friendly and emerging technologies for a sustainable industry, TAPPI JOURNAL, September 2000, Vol. 83(9)
Taiwan holds first symposium on environmentally friendly and emerging technologies for a sustainable industry, TAPPI JOURNAL, September 2000, Vol. 83(9)
Magazine articles
Using climate change policies for u.s. pulp and paper industry efficiency, TAPPI JOURNAL, July 2000, Vol. 83(7)
Using climate change policies for u.s. pulp and paper industry efficiency, TAPPI JOURNAL, July 2000, Vol. 83(7)
Magazine articles
Has Safety Compliance Become "Groundhog Day?â?, Solutions!, March 2006, Vol. 89(3) (106 KB)
Has Safety Compliance Become "Groundhog Day?”, Solutions!, March 2006, Vol. 89(3) (106 KB)
Magazine articles
New england: A paper industry microcosm?, Solutions!, August 2003, Vol. 86(8) (404KB)
New england: A paper industry microcosm?, Solutions!, August 2003, Vol. 86(8) (404KB)
Journal articles
Magazine articles
Probing the molecular weights of sweetgum and pine kraft lignin fractions, TAPPI Journal June 2021
ABSTRACT: The present investigation undertook a systematic investigation of the molecular weight (MW) of kraft lignins throughout the pulping process to establish a correlation between MW and lignin recovery at different extents of the kraft pulping process. The evaluation of MW is crucial for lignin characterization and utilization, since it is known to influence the kinetics of lignin reactivity and its resultant physico-chemical properties. Sweetgum and pine lignins precipitated from black liquor at different pHs (9.5 and 2.5) and different extents of kraft pulping (30•150 min) were the subject of this effort. Gel permeation chromatography (GPC) was used to determine the number average molecular weight (Mn), mass average molecular weight (Mw), and polydispersity of the lignin samples. It was shown that the MW of lignins from both feedstocks follow gel degradation theory; that is, at the onset of the kraft pulping process low molecular weight-lignins were obtained, and as pulping progressed, the molecular weight peaked and subsequently decreased. An important finding was that acetobromination was shown to be a more effective derivatization technique for carbohydrates containing lignins than acetylation, the technique typically used for derivatization of lignin.