Abstract
The polymer obtained from hydrophilic monomers can be transformed into a hydrogel via cross-linking by different cross-linkers. Hydrogels are three-dimensional networks that can absorb several times their weight and swell in water/swelling media, improving the media’s viscosity as a thickener. The cross-linked poly(acrylic acid) microparticles prepared via precipitation polymerization technique are often synthesized by radical polymerization and have carboxylic functional groups in their structure, which make the hydrogel properties such as swelling capacity, particle morphology, and viscosity be controlled by physical factors such as solvent, neutralizer, pH, pK a , zeta potential, and ionic strength of the swelling media, as well as synthetic factors including comonomer, cross-linker, and network type. In this paper, the effects of crucial factors on the synthetic and swelling steps are elaborated to facilitate the achievement of poly(acrylic acid)-based xerogels having desirable rheological properties, such as swelling/viscosity optimization, which is the primary purpose of a thickener in any swelling media.
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Research ethics: Not applicable.
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Author contributions: The authors have accepted responsibility for the entire content of this submitted manuscript and approved its submission.
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Competing interests: The authors state no conflict of interest.
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Research funding: None declared.
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Data availability: Not applicable.
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