Description
The substitution of phenol by lignin in phenol-formaldehyde (PF) resins is one of most promising end uses for lignin valorization. Lignin can be largely recovered as byproduct during pulp production, and its structure depends on the starting raw material. Most of the studies have focused on the use of lignin from softwood or grasses for lignin-phenol-formaldehyde (LPF) resins as they present higher amounts of free, reactive C3 and/or C5 positions when compared to hardwood lignin. However, hardwood is one of the main raw materials used for pulping, which means that all efforts to find value-added applications for this type of lignin are desirable. In our findings we showed that the number of theoretically reactive sites is not the only important factor in the synthesis of LPF resins and their performance. We hypothesize that molecular size and steric hindrance are also factors driving the yields of synthesis. This subject is of great interest as it opens a wide road of opportunities for further discussions related to all characteristics (steric factors, flexibility of lignin macromolecule, etc) that could play a more important role in LPF resins. Furthermore, our results showed new perspectives for application of hardwood kraft lignin, which so far was considered less valuable due the lower number of reactive sites.| Aikajakso | 4 huhtik. 2019 |
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| Tapahtuman otsikko | American Chemical Society National Meeting & Exposition |
| Tapahtuman tyyppi | Conference |
| Konferenssinumero | 257 |
| Sijainti | Orlando, Yhdysvallat, FloridaNäytä kartalla |
| Tunnustuksen arvo | International |