Airbrush-based solution blow spinning of cellulose acetate/poly(vinyl acetate) blends for nonwoven mat formation

The global textile industry faces increasing pressure to adopt cleaner and more resource-efficient manufacturing technologies. Solution blow spinning (SBS) has emerged as a promising route for nonwoven production, offering rapid fibre deposition, simple equipment, and direct in situ formation on substrates. In this study, an airbrush-based SBS process was used to fabricate spray-formed nonwoven structures from an epoxy-free cellulose acetate (CA)/poly(vinyl acetate) (PVAc) formulation. Particular emphasis was placed on understanding the concentration-dependent transition from droplet-dominated deposition to continuous fibre formation. Formulation screening revealed a narrow processability window, with polymer concentration identified as the critical parameter governing jet stability, fibre morphology, and nonwoven cohesion. A clear transition from droplet-rich deposition to stable fibre-forming behaviour was observed as polymer concentration increased, with cohesive, peelable nonwoven mats successfully produced at 23 wt%. Scanning electron microscopy analysis revealed the formation of a continuous interconnected fibrous network with an average fibre diameter of 0.97 ± 0.41 µm. Fourier transform infrared spectroscopy confirmed preservation of the chemical integrity of both polymer components after spraying, while thermogravimetric and differential scanning calorimetry analyses demonstrated adequate thermal stability and predominantly amorphous behaviour. The resulting nonwoven exhibited an average thickness of 0.595 ± 0.049 mm, porosity of 66.0 ± 3.5%, and preliminary mechanical integrity as a self-supporting fibrous structure. These findings provide mechanistic insight into spray-based fibre formation and demonstrate that airbrush-based SBS offers a simple, low-cost, and scalable route for producing cohesive fibrous nonwoven structures, expanding the application potential of SBS beyond conventional biomedical and filtration systems.