593231-72-2Relevant articles and documents
Superacidic porous polymer catalyst and its application in esterification of carboxylic acid
Park, Eun Joo,Bae, Chulsung
, p. 493 - 500 (2017/02/23)
Two solid acid catalysts, SAC1 and SAC2, with porous structure obtained from mesoporous hard template were synthesized and characterized by Fourier transform infrared spectroscopy, acid-base titration, nitrogen adsorption/desorption, scanning electron mic
Room-temperature self-healing polymers based on dynamic-covalent boronic esters
Cash, Jessica J.,Kubo, Tomohiro,Bapat, Abhijeet P.,Sumerlin, Brent S.
, p. 2098 - 2106 (2015/04/27)
Cross-linked polymers constructed with dynamic-covalent boronic esters were synthesized via photoinitiated radical thiol-ene click chemistry. Because the reversibility of the boronic ester cross-links was readily accessible, the resulting materials were capable of undergoing bond exchange to covalently mend after failure. The reversible bonds of the boronic esters were shown to shift their exchange equilibrium at room temperature when exposed to water. Nevertheless, the materials were observed to be stable and hydrophobic and absorbed only minor amounts of water over extended periods of time when submerged in water or exposed to humid environments. The facile reversibility of the networks allowed intrinsic self-healing under ambient conditions. Highly efficient self-healing of these bulk materials was confirmed by mechanical testing, even after subjecting a single site to multiple cut-repair cycles. Several variables were considered for their effect on materials properties and healing, including cross-link density, humidity, and healing time.
Gels and multilayer surface structures from boronic acid containing polymers
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, (2008/06/13)
Boronic acid containing polymers are used to form bioinert gels and multilayer surface structures. These polymers form crosslinked hydrogels, which are highly swollen in water. The crosslinking can either be chemical or physical. Water soluble polymers containing boronic acid groups, such as phenylboronic acid (PBA), can be physically crosslinked by mixing the polymers in water with other polymers containing hydroxyls or carboxylic acids. Alternatively, surfaces can be treated by stepwise incubation with a solution of the boronic acid containing polymer, followed by incubation with a solution of a diol or carboxylic acid containing polymer. Many successive layers can be generated, increasing the thickness of the formed structure at each step. The bioinert gel or surface coating can be used for passivating the surfaces of medical implants (especially those based on transplanted tissue), or for passivating the surfaces of tissues in situ, decreasing the incidence or severity of such pathologic conditions as the formation of post-surgical adhesions, and thrombosis following angioplasty.