Macro- and Nanoscopic Studies of Porous Polymer Swelling

Abstract

A commercial Amberlite XAD7HP resin was investigated as a typical porous polymer which swells in tetraethoxysilane (TEOS). TEOS appears to be an extremely effective polymer swelling agent; thus, it serves as an easily assimilable silica source in polymer−silica composites. The present study discusses the application of light microscopy (LM) and positron annihilation lifetime spectroscopy (PALS) for the studies of macroscopic and microscopic features during the progress of polymer swelling. LM offers precise information on the swelling in the solvent vapor, especially for the well-defined, spherically shaped particles of the polymer. The swelling of a porous polymer consists of the swelling of pore walls and adsorption of the solvent on the internal surface of the walls. PALS provides an opportunity to recognize the sequence of solvent penetration into porous polymer particles. It allows in situ monitoring of the evolution of every free volume in the sample under study.

Porous Polymer Gel Electrolytes Influence Lithium Transference Number and Cycling in Lithium-Ion Batteries

“…We hypothesize that once the opaque film is swelled, the channels reduce to nanoscale diameter on the order of the Debye length. This results in a diffuse electrolyte double layer at the electrolyte-polymer interface in which the anions may be rejected due to partial dipoles at the interface [22,23]. Due to the large volume expansion of O-PEGDMA-VS-0 swollen in 1 M LiPF 6 (EC-DEC) (Table A4), it can be assumed that the pore size shrinks in the presence of electrolyte [22].…”

Advances in the Use of Protein-Based Materials: Toward Sustainable Naturally Sourced Absorbent Materials

“…Tailoring of the morphologies and channel structures has been shown to promote swelling capacity, by increasing the capillary forces in the material or by increasing the surface area of particles present in the material. ,,, Several swelling kinetics parameters, e.g. equilibrium swelling, absorption rate and diffusion efficiency, may be altered merely by changing the final structure of the material without involving any chemical processes. − Examples where the morphological structure affects the absorption efficiency are commonly foams, where the liquid absorption is dominated by capillary mechanisms. ,,,, A difference in pore sizes have also shown to affect absorption properties. , Differences in pore size and pore size distribution have resulted in materials which are suitable for different applications, e.g. pH-sensitive drug delivery systems, tissue engineering, blood, oil spills and plasma absorption, etc. ,− In addition, different coatings and different process treatments of cellulose and protein-based foams have been shown to influence the absorption of liquids with different polarities (e.g., water and/or oil). ,,, In this context, proteins combine foam stability and viscoelasticity with biocompatibility, making them outstanding in tailored foam structures. ,,− Wheat gluten foams have been evaluated for their structure, absorption and swelling properties, with absorption and water swelling of ca.…”

Quaternary functionalized mesoporous adsorbents for ultra-high kinetics of CO2 capture from air

“…2 b). This could be primarily contributed by the swelling process, where it generally induce a 15–25% increase in bulk volume and squeeze mesopores of resins 21 , 22 . On the other hand, the swelling effect also result in higher surface area (Table 1 ) and higher amination efficiency, as the grafting of TMA may barely affect the pore structure of resin due to the small molecular size (0.66 nm) and monolayer grafting 23 .…”