Tang, Liming Weder, Christoph 2010-03-25 New nanocomposites composed of cellulose nanofibers or “whiskers” and an epoxy resin were prepared. Cellulose whiskers with aspect ratios of ∼10 and ∼84 were isolated from cotton and sea animals called tunicates, respectively. Suspensions of these whiskers in dimethylformamide were combined with an oligomeric difunctional diglycidyl ether of bisphenol A with an epoxide equivalent weight of 185−192 and a diethyl toluenediamine-based curing agent. Thin films were produced by casting these mixtures and subsequent curing. The whisker content was systematically varied between 4 and 24% v/v. Electron microscopy studies suggest that the whiskers are evenly dispersed within the epoxy matrix. Dynamic mechanical thermoanalysis revealed that the glass transition temperature (<i>T</i>_g) of the materials was not significantly influenced by the incorporation of the cellulose filler. Between room temperature and 150 °C, i.e., below <i>T</i>_g, the tensile storage moduli (<i>E</i>′) of the nanocomposites increased modestly, for example from 1.6 GPa for the neat polymer to 4.9 and 3.6 GPa for nanocomposites comprising 16% v/v tunicate or cotton whiskers. The relative reinforcement was more significant at 185 °C (i.e., above <i>T</i>_g), where <i>E</i>′ was increased from ∼16 MPa (neat polymer) to ∼1.6 GPa (tunicate) or ∼215 MPa (cotton). The mechanical properties of the new materials are well-described by the percolation model and are the result of the formation of a percolating whisker network in which stress transfer is facilitated by strong interactions between the whiskers. application/pdf https://folia.unifr.ch/global/documents/301639 https://folia.unifr.ch/documents/301639/files/wed_cwe.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1021/am900830h info:eu-repo/semantics/openAccess License undefined ACS Applied Materials and Interfaces. - 2010, vol. 2, no. 4, p. 1073-1080 epoxy resin cellulose whisker nanocomposite percolating network mechanical reinforcement info:eu-repo/classification/udc/53 Cellulose whisker/epoxy resin nanocomposites http://purl.org/coar/resource_type/c_6501