Readily Functionalizable and Stabilizable Polymeric Particles with Controlled Size and Morphology by Electrospray

Abstract

Electrospraying is an effective and facile technique for the production of micro- or nanoparticles with tailored sizes, shapes, morphologies, and microstructures. We synthesized functionalizable poly(styrene-random-glycidyl methacrylate) copolymers and used them to fabricate microparticles via the electrospray technique. The sizes and morphologies of the electrosprayed particles are controlled by altering the process parameters (feed rate and applied voltage), and the composition and thermodynamic properties of the polymer (i.e., compatibility of the polymer with the solvent). We further investigated modifying the surfaces of the electrosprayed particles with 3-mercaptopropionic acid by a simple and efficient thiol-epoxy “click” reaction as a proof-of-concept demonstration that desired functionality can be introduced onto the surfaces of these particles; the outcome was confirmed by various spectroscopic techniques. In addition, the epoxides within the particles easily undergo crosslinking reactions, enabling further effective particle stabilization. The results reveal that the structure and properties of the polymer can be used to fine-tune the structural parameters of the electrosprayed particles, such as their sizes and morphologies, which opens up the possibility of imparting a variety of desired chemical functionalities into the structures of stable organic materials via post-electrospray modification processes.

Fabrication of Polymeric Microparticles by Electrospray: The Impact of Experimental Parameters

“…In recent decades, interest in organic microparticles (MPs) has grown rapidly due to their important applications in various industries such as the pharmaceutical, ceramic, cosmetic, and food industries [1,2]. Between these and various other industrial fields of interest, one can take advantage of MP production in a controlled manner, therefore, the production of these materials has been attempted through several approaches [1,3].…”

“…In recent decades, interest in organic microparticles (MPs) has grown rapidly due to their important applications in various industries such as the pharmaceutical, ceramic, cosmetic, and food industries [1,2]. Between these and various other industrial fields of interest, one can take advantage of MP production in a controlled manner, therefore, the production of these materials has been attempted through several approaches [1,3]. For instance, jet-milling [4], spray drying [5], micro grinding [6], suspension/emulsion polymerization [7], solvent evaporation [8], microfluidics [9], and electrospray (ES) have all been studied for optimal MP fabrication [10].…”

“…Hence, typically, such MPs are manufactured using polymers as the desirable properties of selected polymers (i.e., mechanical, diffusion, electrical, biodegrability, etc.) may be beneficial in adapting particle functionality for such specific applications [1].…”

“…Another example is spray drying in which high operating temperatures, separation of synthesized particles and loss of products using a commercial scale laboratory spray dryer are some significant limitations and challenges [11]. Among these methods, ES technology has attracted a great deal of attention as it is an easy and suitable method for the formation of polymer particles with highly controllable sizes, dispersions, unconventional shapes and unique surface morphologies that cannot be achieved by other conventional MP fabrication methods [1]. In this context, Table 1 demonstrates some advantages and disadvantages between the aforementioned techniques and ES technology.…”

Recent Advances on Nanofiber Fabrications: Unconventional State-of-the-Art Spinning Techniques

“…The stretched-out jet is rapidly accelerated to form the structure of the nanofiber [ 2 ]. The morphology of the resulting nanofibers is effectively controlled by many specific processing parameters, i.e., solution viscosity, applied voltage, solution injection rate, distance between spinneret tip and collector, solvent conductivity, temperature, and humidity [ 18 ].…”