Biobased and degradable thiol–ene networks from levoglucosan for sustainable 3D printing

Abstract

Levoglucosan is a renewable chemical obtained in high yields from pyrolysis of cellulosic biomass, which offers rich functionality for synthetic modification and crosslinking. Here, we report the facile and scalable...

Biobased Transparent Thiol–Ene Polymer Networks from Levoglucosan

“…Similarly, for dipentenoyl-LGA, the COSY spectrum was used to assign the methines H1−H5, with H2 and H4 being shifted downfield compared to H3, indicating esterification at the C2 and C4 hydroxyl groups. Other relevant COSY and HMBC assignments are shown in SI Figure S2. LGA-TA has been previously reported; 24 it is included in this study to serve as a direct comparison to previously published works while also understanding the role of both the number and type of functional groups.…”

“…The hydrolytic degradability of the cured polymer networks was also investigated as previous reports indicate that the ester linkages present in the thiol monomer are susceptible to basemediated hydrolysis (Figure 6). 24,26 Additional ester linkages were introduced during the synthesis of LGA-DP-4SH and LGA-TP-3SH, which provide further sites for degradation with the intent to fully degrade the polymer and potentially recycle the components. The experiments were performed through immersing each sample into a 1.0 M solution of NaOH.…”

Levoglucosenone to 3D-printed green materials: synthesizing sustainable and tunable monomers for eco-friendly photo-curing

“…15 Among the UV-curing-based technologies, thiol-ene click chemistry represents an attractive process which allows high conversion due to the click-characteristic (i.e., a 1 : 1 reaction between thiol and ene functionalities) and the lack of oxygen inhibition. [16][17][18] This chemistry has been explored with several bio-based platforms in recent years, such as levoglucosan, 19 terpenes, 20,21 furans, 22,23 and isosorbide derivatives. [24][25][26] However, to the best of our knowledge, no studies have been conducted on the UV-curing of LGO derivatives yet.…”

“…Furthermore, the monomers' chain length can be varied to fine-tune material properties, and the ester bonds can be susceptible to degradation at the end of the material's life. 19,41 To this end, the polythiol chosen in this study, trimethylolpropane tris(3-mercaptopropionate) (TMPMP), encompasses ester linkages in its backbone. The photo-crosslinking between bis-allylated monomers and TMPMP was investigated through different techniques (i.e., real-time FTIR, photo-DSC and photo-rheology) and proved very efficient.…”

“…, a 1 : 1 reaction between thiol and ene functionalities) and the lack of oxygen inhibition. 16–18 This chemistry has been explored with several bio-based platforms in recent years, such as levoglucosan, 19 terpenes, 20,21 furans, 22,23 and isosorbide derivatives. 24–26 However, to the best of our knowledge, no studies have been conducted on the UV-curing of LGO derivatives yet.…”