Preparation Of Special Shape Gel Particles From Light Curable Monomers And Application Studies

Specially shaped gel particles have been of great interest due to their large specific surface area,fast internal and external mass transfer capability,and anisotropic responsiveness.They have been widely used in a range of fields such as cell encapsulation,drug release,biosensing,and micro-robotics.Thanks to the special morphology of gel particles,their functions in some fields cannot be satisfied by a single spherical type.Therefore,how to obtain special shaped gel particles has become a research topic in recent years.The preparation methods of special shaped gel particles are gradually diversified,such as soft lithography,microfluidic method,electrospray method,electrodeposition method,drop-in molding method,etc.In this paper,different shapes of gel particles were prepared from acryloyloxyethyl trimethyl ammonium chloride(DAC)using a combination of vortex freezing and photopolymerization.Vortex freezing is a method that produces a series of fluid intermediates with non-spherical shapes when droplets hit the surface of the miscible solution,and fixes these intermediates by cross-linking in a way that matches the deformation process.In previous studies,the preparation of gel particles by drop-in cross-linking was mainly limited to polymers,while small molecules have not been reported so far.The reasons for the difficulty of forming small molecules are mainly divided into two aspects: on the one hand,the low viscosity makes it difficult to maintain the intermediate shape of small molecule droplets while deforming;on the other hand,it is difficult to match the rate of deformation of small molecule droplets and the rate of crosslinking and shaping,which makes it difficult to prepare gel particles of various shapes.Therefore,compared with polymers,the preparation of special shaped gel particles from small molecule materials is more challenging for drop cross-linking molding method.Unlike the previous experimental materials used,which were polymers and cross-linked by ionic bonding,this study pioneered a new system that enables the preparation of various shaped particles from small molecules,deformation by droplet impingement on the liquid surface,and shaping by rapid light curing compared to previous research work.This production method allows the preparation of a range of PDAC gel particles with different shapes,such as round cake,ellipsoid,bowl,tadpole,and shapes with miscellaneous edges,and explains the changes in the gel particles during the deformation process using the hydrodynamic parameters viscosity ratio,Reynolds number,and Weber number.In addition to the combination of DAC and glycerol receiver baths,varying different types of receiver baths further explains the role of the variation of the viscosity and height of the receiver bath for the gel particle deformation.Specially shaped gel particles were prepared using some other light-curing monomers to illustrate the feasibility of the method.In addition,bowl-shaped gel particles were prepared using a mixture of DAC and acrylamide in the above manner,and the adsorption of anionic dyes was achieved by these quaternary ammonium salt type bowl particles.Kinetic and adsorption isotherm curves were fitted using Congo red dye as the adsorption model,and the results showed that the adsorption of this gel particle was mainly a monolayer chemisorption based.By comparing the adsorption performance of spherical and bowl-shaped gel particles,it was found that the adsorption performance of both bowl-shaped gel particles was better than that of spherical gel particles.In addition,the prepared gel particles have certain acid and alkali resistance and recyclability,which provide a possibility for further practical use.This method for the production of special shaped gel particles further expands the diversity for the selection of materials and provides some reference value for the preparation and application of subsequent special shaped gel particles.