Herein, we compared the microphase-separation behavior and mechanical properties of cellulose- and amylose-based block copolymers (BCPs). Various cellooligosaccharide triacetate-b-poly(δ-decanolactone)-b-cellooligosaccharide triacetates (AcCel n-b-PDL-b-AcCel ns), which are cellulose-based ABA-type BCPs, with PDL molecular weights of approximately 5, 10, and 20 kg mol -1and PDL volume fractions of 0.65, 0.77, and 0.87, were synthesized from α,ω-diazido-end-functionalized PDLs and propargyl-end-functionalized cellooligosaccharide triacetates via click chemistry. We adopted the cellodextrin-phosphorylase-mediated oligomerization of α-glucose-1-phosphase in the presence of a propargyl-end-functionalized cellobiose primer to synthesize the functional cellooligosaccharide segment. The maltooligosaccharide triacetate-b-poly(δ-decanolactone)-b-maltooligosaccharide triacetate (AcMal n-b-PDL-b-AcMal ns) amylose counterparts were also synthesized in a similar manner. Small-angle X-ray scattering experiments and atomic force microscopy revealed that AcCel n-b-PDL-b-AcCel ns are more likely to microphase-separate into ordered nanostructures compared to AcMal n-b-PDL-b-AcMal ns, despite their comparable chemical compositions and molecular weights. Furthermore, AcCel n-b-PDL-b-AcCel ns exhibited significantly superior mechanical performance compared to their amylose counterparts under tensile testing, with Young’s modulus and stress at break of AcCel n-b-PDL 10k-b-AcCel nbeing 2.3 and 1.8 times higher, respectively, than those of AcMal n-b-PDL 10k-b-AcMal n. The enhanced microphase-separation and mechanical properties of AcCel n-b-PDL-b-AcCel ns were found to be attributable to the stiffness and crystalline nature of the AcCel nsegments. These results demonstrate the advantages of using cellulose derivatives to synthesize novel biofunctional materials.
- block copolymers
- sustainable elastomers