An all-water-based procedure for “controlled” polymer grafting from cellulose nanofibrils is reported. Polymers and copolymers of poly­(ethylene glycol) methyl ether methacrylate (POEGMA) and poly­(methyl methacrylate) (PMMA) were synthesized by surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP) from the cellulose nanofibril (CNF) surface in water. A macroinitiator was electrostatically immobilized to the CNF surface, and its amphiphilic nature enabled polymerizations of both hydrophobic and hydrophilic monomers in water. The electrostatic interactions between the macroinitiator and the CNF surface were studied by quartz crystal microbalance with dissipation energy (QCM-D) and showed the formation of a rigid adsorbed layer, which did not desorb upon washing, corroborating the anticipated electrostatic interactions. Polymerizations were conducted from dispersed modified CNFs as well as from preformed modified CNF aerogels soaked in water. The polymerizations yielded matrix-free composite materials with a CNF content of approximately 1–2 and 3–6 wt % for dispersion-initiated and aerogel-initiated CNFs, respectively.

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Cellulose nanofibril (CNF)‐networks are modified by the addition of small amounts (below 10 wt%) of well‐defined cationic nanolatexes synthesized through reversible addition–fragmentation chain‐transfer‐mediated polymerization‐induced self‐assembly (PISA). Minute amounts of nanolatex inclusions lead to increased tensile and shear moduli, indicating that nanolatexes can act as bridging‐points between CNFs. At higher nanolatex content, this stiffening effect is lost, likely due to interactions between nanolatexes leading to plasticization. The influence of nanolatex content and size on interparticle distance is discussed and is used as a tool to understand the effects observed in macroscopic properties. Upon annealing, the stiffening effect is lost due to the softening of the nanolatexes, indicating that the core–shell morphology is a prerequisite for this effect. These systems form a versatile platform to develop fundamental insights into complex condensed colloidal systems, to ultimately aid in the development of new sustainable material concepts.

Allyl saccharide/vinyl copolymers were synthesized using renewable feedstocks (α,α′-trehalose and d-glucose) to obtain ‘green monomers’. Properly designed synthetic procedures were used to obtain copolymers with high purity and without protection/deprotection steps in agreement with the principles of green chemistry and industrial sustainability. The use of saccharide derivatives as monomers allowed products to be obtained that showed high affinity and compatibility for the cellulosic substrates, like paper or wood, and that were suitable for applications like adhesion or consolidation in the field of cultural heritage. All reaction products were characterized by FT-IR and NMR spectroscopies and SEC analyses, while thermal properties were evaluated by DSC analyses.

An in-depth characterization of PDMAEMA prepared by ATRP was conducted, with a focus on end group analysis. This work discusses analytical tools providing essential information about the extent of control over DMAEMA polymerization and chain extension.