How to modification lignin by esterification?
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Lignin can be modified through esterification by using different methods. One approach is to use lipase as a selective catalyst for the esterification of aliphatic OH groups in lignin compounds, while preserving their antioxidant capacity . Another method involves the esterification of lignin with an anhydride group, resulting in a modified lignin with a terminal carboxyl group . Microwave assistance can also be used to achieve rapid esterification modification of lignin, resulting in a high esterification degree . Reactive extrusion (REX) has been studied as a solvent-free and continuous process for lignin esterification, resulting in lignin esters with improved thermal properties . Additionally, esterification of lignin with fatty acids, such as oleic acid, can increase its dispersibility in lipophilic thermoplastic polymers, making it a promising candidate for incorporation in commercial thermoplastics .
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9 Citations | The paper describes the modification of lignin by esterification using fatty acids such as oleic acid. The resulting lignin ester has a molecular weight of 5.8 kDa and a glass transition temperature (Tg) of 70 °C. |
18 Citations | The paper discusses the esterification of plasticized Kraft lignin using reactive extrusion. The authors used succinic and maleic anhydrides as reactants and studied the chemical structure and properties of the resulting lignin esters. |
| The paper provides a lignin modification method based on microwave assistance, which involves mixing lignin with an acyl chloride reagent and a catalyst, heating the mixture using microwaves, and terminating the reaction with ethanol. The modified lignin obtained has a high esterification degree. | |
| The paper discusses the selective enzymatic esterification of lignin-derived phenolics using lipase as a catalyst. The esterification is targeted at the aliphatic OH groups in the lignin compounds to increase their compatibility with hydrophobic product matrixes while preserving their antioxidant capacity. The paper provides details on the reaction conditions and yields achieved. However, it does not provide a detailed step-by-step procedure for lignin modification by esterification. | |
| The paper describes the modification of lignin by esterification using a simple reaction of a hydroxyl group with an anhydride group to produce COOH-lignin with a terminal carboxyl group. |
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