Nonporous, Strong, Stretchable, and Transparent Electrospun Aromatic Polyurea Nanocomposites as Potential Anticorrosion Coating Films

Abstract

This study, for the first time, focused on the fabrication of nonporous polyurea thin films (~200 microns) using the electrospinning method as a novel approach for coating applications. Multi-walled carbon nanotubes (MWCNTs) and hydrophilic-fumed nanosilica (HFNS) were added separately into electrospun polyurea films as nano-reinforcing fillers for the enhancement of properties. Neat polyurea films demonstrated a tensile strength of 14 MPa with an elongation of 360%. At a loading of 0.2% of MWCNTs, the highest tensile strength of 21 MPa and elongation of 402% were obtained, while the water contact angle remained almost unchanged (89°). Surface morphology analysis indicated that the production of polyurea fibers during electrospinning bonded together upon curing, leading to a nonporous film. Neat polyurea exhibited high thermal resistance with a degradation temperature of 380 °C. Upon reinforcement with 0.2% of MWCNTs and 0.4% of HFNS, it increased by ~7 °C. The storage modulus increased by 42 MPa with the addition of 0.2% of MWCNTs, implying a superior viscoelasticity of polyurea nanocomposite films. The results were benchmarked with anti-corrosive polymer coatings from the literature, revealing that the production of nonporous polyurea coatings with robust strength, elasticity, and thermal properties was achieved. Electrospun polyurea coatings are promising candidates as flexible anti-corrosive coatings for heat exchanges and electrical wires.

Unveiling Carbon Fiber Reinforced Polyurea Composites Engineered through Vacuum Assisted Resin Transfer Molding: An In-depth Analysis of Mechanical, Thermal, and Degradation Performance

“…This is due to the highly elastomeric property of polyurea, allowing for a rearrangement of the matrix chains after the load is removed. 24 This may have resulted in a redistribution of the stress through the viscoelastic polyurea matrix, resulting in the undeformed sample.…”

“…19−21 These studies showed that polyurea can absorb and store significant amounts of energy and reduce shock waves on the composites. 22 Polyurea-infused fibers, however, have never been explored yet due to their fast curing and high viscosity. 23,24 The main goals of the VARTM technique are to achieve a better fiber−resin ratio and less resin utilization and yield good quality products with lesser voids.…”

“…22 Polyurea-infused fibers, however, have never been explored yet due to their fast curing and high viscosity. 23,24 The main goals of the VARTM technique are to achieve a better fiber−resin ratio and less resin utilization and yield good quality products with lesser voids. On the other hand, slow cycle time, surface finish, and resin gelation before impregnation for large structures are some significant challenges of the vacuum infusion technique.…”

“…Polyurea and FRPs have been used for blast and ballistic mitigation by sandwiching polyurea in between the layers of aluminum and carbon fiber-reinforced epoxy. − These studies showed that polyurea can absorb and store significant amounts of energy and reduce shock waves on the composites . Polyurea-infused fibers, however, have never been explored yet due to their fast curing and high viscosity. , The main goals of the VARTM technique are to achieve a better fiber–resin ratio and less resin utilization and yield good quality products with lesser voids. On the other hand, slow cycle time, surface finish, and resin gelation before impregnation for large structures are some significant challenges of the vacuum infusion technique .…”

Reinforcement of nest‐like Zn layers on the surface of carbon fibers for rigid polyurethane composites

“…[3][4][5] At present, the researches on RPU are mainly focused on the improvement of strength and toughness. Researchers have attempted to add different types of reinforcement materials to RPU in order to improve its mechanical properties, such as inorganic particles, 6,7 metal particles, 8,9 fibers 10,11 and organic nanoparticles, 12,13 and so on.…”