1-Butanol absorption in poly(styrene-divinylbenzene) ion exchange resins for catalysis

Abstract

The swelling behaviour of poly(styrene-co-divinylbenzene), P(S-DVB), ion exchange resins in 1-butanol (BuOH) has been studied by means of atomistic classical molecular dynamics simulations (MD). The topological characteristics reported for the resin in the dry state, which exhibited complex internal loops (macropores), were considered for the starting models used to examine the swelling induced by BuOH contents ranging from 10% to 50% w/w. Experimental measurements using a laser diffraction particle size analyzer indicate that swelling causes a volume variation with respect to the dry resin of 21%. According to MD simulations, such a volume increment corresponds to a BuOH absorption of 31-32% w/w, which is in excellent agreement with the indirect experimental estimation (i.e. 31% w/w). Simulations reveal that, independently of the content of BuOH, the density of the swelled resin is higher than that of the dry resin, evidencing that the alcohol provokes important structural changes in the polymeric matrix. Thus, BuOH molecules cause a collapse of the resin macropores when the content of alcohol is ≤20% w/w. In contrast, when the concentration of BuOH is close to the experimental value (∼30% w/w), P(S-DVB) chains remain separated by pores faciliting the access of the reactants to the reaction centers. On the other hand, evaluation of both bonding and non-bonding interactions indicates that the mixing energy is the most important contribution to the absorption of BuOH into the P(S-DVB) resin. Overall, the results displayed in this work represent a starting point for the theoretical study of the catalytic conversion of BuOH into di-n-butyl ether in P(S-DVB) ion exchange resins using sophisticated electronic methods.

Cross‐linked polystyrene and polydivinylbenzene release significant amounts of carbon monoxide and hydrogen at ambient temperature

“…Cross-linked polystyrene (CL-PS), or styrene-divinylbenzene copolymer, and polydivinylbenzene (PDVB) are widely used as the platform materials for various functional resins that are used for the separation of the mixtures of chemical and biological products and as plastic blast materials. [1][2][3][4][5][6][7] These polymers have unreacted pendant vinyl groups, which undergo aging, or oxidation with air, giving rise to the formation of OH and (CO)CH 3 groups. 8 This aging process has been known to proceed even at room temperature and becomes accelerated as temperature increases.…”

Ion-Exchange Fabrication of Hierarchical Al-MOF-Based Resin Catalysts for the Tandem Reaction

“…Recently, the ion-exchange strategy has been widely used for preparing the target products with specific functional groups. − We hypothesized that an ion-exchange strategy would efficiently improve the bonding strength between MOF particles and resin. , Herein, leveraging the exchange property of the anionic Amberlite IRA900­(Cl) resin, we prepared hybrid MIL-101­(Al)–NH 2 catalysts with a particle size of about 1 mm, large pore volume, and stable structure. Specifically, by exchanging MOF ligands to ions on the surface of resin and subsequent in situ crystal growth, catalytic MOF species were grown via a green stepwise process involving water as the key solvent (Scheme ).…”

Critical Assessment of the Thermodynamics in Acidic Resin-Catalyzed Esterifications

“…Cross-linked polymer resins, either unmodified or functionalized with specific groups, are used in a broad range of applications, including, among others, water treatment, chromatography, hydrogen storage, and hydrometallurgy. − Additionally, functionalized resins are increasingly used as high-performance heterogeneous catalysts for organic synthesis reactions, such as (trans)­esterifications, etherifications, dehydrations, aldol reactions, Suzuki–Miyaura cross-couplings, phenol alkylations, and so forth. − It should, however, be noted that these materials exhibit a remarkable phenomenon as compared to other types of heterogeneous catalysts. Namely, when a dry resin is allowed to make contact with a liquid, it tends to swell, that is, a portion of the liquid is sorbed by the resin, resulting in an increase of its volume. ,,− The sorption phenomena occurring during the swelling of a resin can be classified into two categories: (i) absorption of liquid into the resin pores and (ii) adsorption of components onto functional groups.…”