Institut de Chimie de Nice, Université Côte d'Azur, CNRS, UMR 7272, 06108 Nice, France.
Molecules. 2022 May 17;27(10):3212. doi: 10.3390/molecules27103212.
The chemistry of biomass-derived furans is particularly sensitive to ring openings. These side reactions occur during furfuryl alcohol polymerization. In this work, the furan ring-opening was controlled by changing polymerization conditions, such as varying the type of acidic initiator or the water content. The degree of open structures (DOS) was determined by quantifying the formed carbonyl species by means of quantitative F NMR and potentiometric titration. The progress of polymerization and ring opening were monitored by DSC and FT-IR spectroscopy. The presence of additional water is more determining on ring opening than the nature of the acidic initiator. Qualitative structural assessment by means of C NMR and FT-IR shows that, depending on the employed conditions, poly(furfuryl alcohol) samples can be classified in two groups. Indeed, either more ester or more ketone side groups are formed as a result of side ring opening reactions. The absence of additional water during FA polymerization preferentially leads to opened structures in the PFA bearing more ester moieties.
生物质衍生呋喃的化学性质对开环反应特别敏感。这些副反应发生在糠醇聚合过程中。在这项工作中，通过改变聚合条件来控制呋喃环的开环，例如改变酸性引发剂的类型或含水量。通过定量 F NMR 和电位滴定定量测定形成的羰基种类来确定开环结构的程度（DOS）。通过 DSC 和 FT-IR 光谱监测聚合和开环的进展。额外水的存在对开环的影响大于酸性引发剂的性质。通过 C NMR 和 FT-IR 进行的定性结构评估表明，根据所采用的条件，聚（糠醇）样品可以分为两组。实际上，由于侧环开环反应，形成的侧基是更多的酯基或酮基。在 FA 聚合过程中不添加额外的水，会优先导致 PFA 中形成更多酯基的开环结构。
