Improvement of Mechanical Properties and Self-Healing Efficiency by Ex-Situ Incorporation of TiO2 Nanoparticles to a Waterborne Poly(Urethane-Urea)

Abstract

This research work was focused on the incorporation of TiO2 nanoparticles into synthesized solvent-free waterborne poly(urethane-urea) (WPUU) based on hydrophilic poly(ethylene oxide) (PU0) in order to improve both the mechanical properties and self-healing effectiveness of a polymer matrix. The incorporation of TiO2 nanoparticles resulted in a successful enhancement of the mechanical properties of nanocomposite films when compared to PU0. Simultaneously, the obtained nanocomposite films did not only maintain the self-healing ability of the PU0 film, measured by means of mechanical properties after successive cutting/recovery cycles, but they also showed a higher self-healing efficiency than the PU0 film. Moreover, the well-dispersed TiO2 nanoparticles, visualized by atomic force microscopy (AFM), kept their conductive properties when embedded in the PU0 matrix, as was confirmed by electrostatic force microscopy (EFM). This research work described a simple and industrially appealing way to control the dispersion of commercially available TiO2 nanoparticles in waterborne poly(urethane-urea) for the designing of inorganic/organic hybrid nanocomposites with enhanced mechanical properties and self-healing efficiency, in which TiO2 nanoparticles preserved their conductive properties within the polymer matrix.

Optimization of adhesive performance of waterborne poly(urethane-urea)s for adhesion on high and low surface energy surfaces

“…All three WPUUs based on triblock copolymers showed better probe-tack adhesion than did the PU0, which is based on PEO only. This result can be explained by the relatively high elastic modulus of PU0, reported elsewhere [36] to be 6.2 ± 1.7 MPa, which is far above the acceptable range for PSAs, according to the Dahlquist criterion (which is on the order of 0.1 MPa) [7,35,37]. Triblock copolymer-based WPUUs presented lower elastic moduli and fulfilled the Dahlquist criterion because of the addition of the PPO block, which presents -CH3 side groups.…”

Structure‐property relationships of waterborne polyurethane (WPU) in aqueous formulations

“…Díez-García, 2019 [83] Zinc oxide 7 wt% 0D No Textile treatment Patti, 2019 [11] Graphene oxide and silica 0.2 wt% 2D/0D Functionalization of graphene oxide with epoxy groups and nanosilica with amine groups Improvement in mechanical and thermal properties, hydrolysis resistance and water resistance for leather coatings Kale, 2019 [75] Silica 25 wt% 0D Hydrophilic or hydrophobic functionalization Textile treatment Patti, 2020 [14] Cellulose and silver 0.5 wt% Cellulose 5 wt% silver 1D/0D No Antimicrobial properties on wood board Cheng, 2020 [76] Magnetite nanoparticles 3 wt% 0D No Reduction of electromagnetic reflections in vehicles such as airplanes and ships by decreasing the susceptibility to radar.…”

Application of Shape Memory and Self-Healable Polymers/Composites in the Biomedical Field: A Review

“…Optical images of superficially damaged and thermally healed PGS-UPy samples (55 °C) for different time points were captured (Figure a,b) . Moreover, to quantify the self-healing efficiency, the pristine and healed scaffolds are subjected to a tensile test, and the HE is calculated by the following equations: normalH normalE normals normalt normalr normale normals normals = σ normalh normale normala normall normale normald σ normalo normalr normali normalg normali normaln normala normall × 100 % normalH normalE normals normalt normalr normala normali normaln = ε normalh normale normala normall normale normald ε normalo normalr normali normalg normali normaln normala normall × 100 % where σ original and ε original are the initial tensile strength and elongation at break, respectively, and σ healed and ε healed are the tensile strength and elongation at break of the healed specimens, respectively. − Yan et al prepared the self-healable blend of poly(ethylene- co -methacrylic acid) sodium ionomer (EMNa) and poly(ethylene- co -methyl acrylate) (EMA). The self-healing efficiency of the specimens was quantified by using static uniaxial tensile measurements.…”