The influence of Ni/Mg content of synthetic Mg/Ni talc on mechanical and thermal properties of waterborne polyurethane nanocomposites

Abstract

Waterborne polyurethanes (WPUs) present interesting properties when compared to their solvent-based counterpart besides being organic solvent free. WPUs also present some drawbacks such as low thermal and mechanical properties. The goal of this work was to synthesize and characterize new synthetic talc in a gel form with different magnesium (Mg) and nickel (Ni) ratios in their chemical structure Si 4 (Mg x Ni 1−x ) 3 O 10 (OH) 2 with 0 < x < 1 and to evaluate their influence on mechanical and thermal properties when used as filler in WPU matrix in order to obtain new nanocomposites as well. WPU/STMg x Ni y nanocomposites were prepared by physical mixing and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), atomic force microscopy (AFM) and mechanical dynamic analysis (DMTA). Improvements in nanocomposites mechanical properties in relation to pristine WPU matrix were observed for samples with higher synthetic talc content. The variation of the amount of Mg and Ni in synthetic talc composition altered the storage and loss modules results being higher for nanocomposites obtained with synthetic talc samples with higher Ni content in their compositions. Tg varied according to synthetic talc content. Synthetic talc with different metal content in their composition changes WPU nanocomposites thermal and mechanical properties. These fillers can be used to design nanocomposites with desired applications.

Synthetic silico-metallic mineral particles SSMMP: A new option for CO2 capture and CO2/N2 separation from post-combustion technology

“…Table 3 also shows the density values of the samples under study in the range of 1.89-2.70 g/cm 3 , attributed to the similarity of the structure of synthetic samples with the one of natural talc, and the presence of functional groups attached to their structure for the functionalized samples. S5) shows for ST-M1 and ST-M2 the presence of intense diffraction peaks, very similar to those found for Luzenac talc corroborating the crystallinity of these materials (Dias et al, 2015;Prado et al, 2020). SSMMP-5%-Im(Bu)-I present an X-ray diffraction pattern with broad and low-intensity diffraction peaks, confirming the lower stacking order and growth in the ab plane, and the amorphous structure (Claverie et al, 2018).…”

“…Unlike talc, these talc precursor materials have many reactive groups (Si-OH and Mg-OH) free on their surface (Chabrol et al, 2010;Dumas, 2013;Claverie et al, 2018). Among the applications already presented for these materials are the absorption of organic compounds (Ciesielczyk and Krysztafkiewicz, 2007;Ciesielczyk et al, 2007aCiesielczyk et al, , 2007b and polymer fillers (Dietemann, 2012;Dias et al, 2015Dias et al, , 2016Prado et al, 2020). The synthesis of talc precursors grafted with ionic liquids, using a fast, one-pot method, with low energy expenditure and using only an aqueous medium for dissolving the reagents, was patented (Dumas et al, 2013a).…”