Copolymers of a fluorinated acrylate and styrene were synthesized to enhance the viscosity of liquid carbon dioxide. The phase behavior of mixtures of these polymers with carbon dioxide was measured at 295 K and pressures from 6.70 to 48.28 MPa. Miscibility pressures decreased with a decrease in the styrene content and increased as molecular weight increased. These polymers were also found to significantly enhance the viscosity of carbon dioxide, by a factor of ca. 5 to 400 at concentrations from 1 to 5 wt %. The optimal composition for viscosity enhancement was 29 mol % styrene-71 mol % fluoroacrylate.

Compounds with strong thermodynamic affinity for carbon dioxide (CO(2)) have been designed and synthesized that dissolve in CO(2), then associate to form gels. Upon removal of the CO(2), these gels produced free-standing foams with cells with an average diameter smaller than 1 micrometer and a bulk density reduction of 97 percent relative to the parent material.

Scheme 1. The structures of closo-carborane-functionalized facial and meridional iridium(III) complexes.

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Ionic liquids (ILs) with different cations and anions were used to study the effects on 5-hydroxymethylfurfural (HMF) preparation. It was found that both aggregations of cations and hydrogen bonds of anions with fructose played important roles. Molecular dynamics simulations were also performed to explain the experimental results.

Both neutral and cationic iridium(III) complexes containing carborane units were synthesized. Bulky carboranes can significantly improve phosphorescence quantum yields of these complexes and the electronic effect of carboranes can evidently tune emission wavelengths of cationic complexes.

Hollow silica spheres (HSS) with special interior spaces, high specific surface area and excellent adsorption and permeability performance were synthesized via micelle-template method using cetyl trimethyl ammonium bromide (CTAB) micelles as soft template and tetraethoxysilane (TEOS) as silica precursor. SEM, TEM, FT-IR, XRD, DLS and BET-BJH were carried out to characterize the morphology and structure of as-obtained samples. The results demonstrated that the samples were amorphous with a hollow structure and huge specific surface area. The growth of HSS was an inward-growth mechanism along template. Notably, we have provided a new and interesting fundamental principle for HSS materials by precisely controlling the ethanol-to-water volume ratio. In addition, the as-obtained HSS were mixed with waterborne polyurethane (WPU) to prepare WPU/HSS composite membrane. Various characterizations (SEM, TEM, FT-IR and TGA) revealed the morphology, polydispersity and adherence between HSS and WPU. Performance tests showed that the introduction of HSS can improve the water vapor permeability of composite membrane, promoting its water resistance and mechanical performance at the same time.

An efficient strategy was designed to realize spontaneous recovery of mechanochromic luminescence by carborane-functionalized anthracene derivatives. A metastable charge-transfer emission from anthracene to o-carborane is responsible for this process.