In-situ real-time monitoring of hydroxyethyl modification in obtaining uniform lignin derivatives

Data on making uniform lignin building blocks via in-situ real-time monitoring of hydroxyethyl modification

“…The in-situ real-time monitoring data, including the CO 2 amount and CO 2 production rate, were tabulated in Table 1 . With different amounts of CO 2 , the modified lignin was analyzed by 31 P and 13 C NMR quantitatively based on the previous methods, while the original data was uploaded to the Mendeley Data [4 , 5 , 7 , 8] . Fig.…”

“…The molar mass of unmodified and modified lignin samples were analyzed by the ASTRA software and tabulated in Table 4 [7] . The molecular weight traces were based on the MALS detector in our related research article [8] .…”

One-pot route to convert technical lignin into versatile lignin esters for tailored bioplastics and sustainable materials

“…Firstly, modification such as etherification of phenolic groups in lignin using epochlorihydrin 26 , alkyl oxide 27 , or organic carbonates [28][29][30][31][32] always is accompanied by side reactions, causing unknown structural changes and increased molar mass with a significant change in the molecular weight distribution; in some cases, the molar mass and polydispersity will rise to over 20-fold of its original value. 24,[26][27][28][29][33][34][35] Also, these derivatization processes, such as esterification, utilized toxic and water-reactive reagent (e.g., halogenated compounds) with the harmful catalysts (e.g., pyridine) and solvents (e.g., DMF, THF). [36][37][38] Beyond the "greenness" issues that cloud these chemicals, the multiple solvent mixtures lead to a more complex solvent parameter and additional difficulties to realize the separation of reagents mixture (solvents, reaction reagents, and catalysts) and the isolation of lignin from this mixture.…”

“…38,[44][45][46] Consequently, it leads to a unique path in advancing lignin-based materials for various applications. 3,17,31,33,46,47 In comparison with aforementioned process, researchers recently developed a series of novel and greener esterification approaches such as modification in multiphase emulsions 48 , acidic ionic liquid 49 , and supercritical conditions 50 , and the one pot strategy. As highlighted above with the one pot study, Zhu and his collaborators performed this process during isolation 51,52 enhancing the value of lignin while reducing processing steps.…”

“…47 Due to the high selectivity toward AlOH of this route, a real-time monitoring hydroxyethyl reaction with ethylene carbonate was required as the first step to monitor the amount of AlOH in technical lignin and enhance their reactivity and uniformity of the resulting lignin. 31,33 However, it is recognized that there are trade-offs when compared with other traditional approaches, such that using anhydrides can achieve high degrees of substitution at lower reaction temperatures and times, but also have lower atom economy values and potential toxicity of some of the catalysts or reagents.…”