Nanosized Poly(ethylene glycol) Domains within Reverse Micelles Formed in CO₂

Abstract

Tiny reactors: By using a surfactant (see picture), domains of poly(ethylene glycol) (PEG) at the nanometer scale are dispersed within reverse micelles formed in supercritical CO2. The size and properties of the PEG domains are tuneable by changing the PEG content. Furthermore, the PEG domains have been used as nanoreactors to synthesize highly dispersed gold nanocrystals.

Bifunctional Boron Phosphate as an Efficient Catalyst for Epoxide Activation to Synthesize Cyclic Carbonates with CO2

“…As shown in Figure b, the PC yield was affected significantly by CO 2 pressure, and the PC yield increased in the low pressure region (0.5 MPa–4 MPa) but decreased in high pressure region (4 MPa–10 MPa). A maximum PC yield of 98 % could be obtained under 4 MPa CO 2 at 110 °C with a reaction time of 6 h. This tendency could be explained by the phase behavior of the reaction system, which consisted of the vapor phase (CO 2 ‐rich phase) and the liquid phase (PO‐rich phase, where the reaction happened) observed through a view cell reported previously . First, the amount of CO 2 in the PO‐rich phase increased with increasing CO 2 pressure, which favored the cycloaddition reaction as CO 2 acted as a reactant.…”

“…Am aximum PC yield of 98 %c ould be obtained under 4MPa CO 2 at 110 8Cw ith ar eactiont ime of 6h.T his tendency could be explained by the phase behavior of the reaction system, which consisted of the vapor phase (CO 2 -rich phase) and the liquid phase (PO-rich phase, where the reaction happened) observedt hrough av iew cell reported previously. [45] First, the amount of CO 2 in the PO-rich phase increased with increasing CO 2 pressure, which favoredt he cycloaddition reaction as CO 2 acted as ar eactant. On the other hand, more PO was extracted into the CO 2 -rich phase with higher pressure and the concentrationo fP Od ecreased in the PO-richp hase, which decreased the reactionr ate.…”

CO2-in-PEG emulsion-templating synthesis of poly(acrylamide) with controllable porosity and their use as efficient catalyst supports

“…In addition, the effect of the CO 2 was also more obvious on the distribution of the macropores (Fig. 37 Therefore, the volume of mesopores compared to the volume of macropores changed with the CO 2 pressure. In addition, the synthesized PAM prepared in PEG alone or the system of PEG and P104 in the absence of CO 2 showed no macropores, which was consistent with the results obtained from the SEM examinations (Fig.…”

“…Besides compressed CO 2 , liquid poly(ethylene glycol)s (PEGs) are regarded as another green solvent. 37 However, the emulsion consisted by PEG and CO 2 has not been explored. More importantly, their properties are tunable by simply changing the molecular weight of PEG.…”

Building Close Ties Between CO2 and Functional Two‐Dimensional Nanomaterials with Green Chemistry Strategy

“…Because of the nonpolar property as well as weak van der Waals forces of SC CO 2 , a dispersion of a hydrophilic or lipophilic phase in a CO 2 continuous phase can be formed . Thus, the reversed micelles can be built with the aid of surfactant–water solutions in SC CO 2 .…”