Cellulose nanocrystals (CNCs) are widely used as a reinforcing nanofiller in polymer nanocomposites because of their high stiffness and strength, high aspect ratio, and renewable nature. However, hydrogen-bonding promoted by the abundant hydroxyl groups on the surface of the CNCs renders these nanoparticles prone to aggregation in many polymer matrices. This issue can be overcome by designing one-component nanocomposites (OCNs) that are based on “hairy nanoparticles” (HNPs), which in turn are made by growing the matrix polymer from the nanoparticles. Here we introduce OCNs made from HNPs that were synthesized by grafting homo- and gradient copolymers from the CNCs by way of surface-initiated atom transfer radical polymerization. We show that the combination of an inner block (towards the CNCs) of a low-T<sub>g</sub> polymer (poly(methyl acrylate)) and an outer block of a high-T<sub>g</sub> polymer (a gradient copolymer rich in poly(methyl methacrylate)) leads to materials that display the characteristic thermomechanical features of a microphase separated system consisting of rubbery poly(methyl acrylate) domains, glassy poly(methyl methacrylate) domains, and well-dispersed CNCs. As a result, the novel nanocomposites display thermomechanical and mechanical properties that can be tuned via the specific composition, and combine appreciable strength, stiffness, and toughness.

Structure-property relationship of one-component nanocomposites (OCNs) based on surface functionalized cellulose nanocrystals

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.