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The Zn–Co double metal cyanide (DMC) complex is regarded as a promising catalyst for the copolymerization of CO 2 and propylene epoxide (PO). Various methods have been adopted to improve the catalytic performance of DMC. In this study, polyvinylpyrrolidone (PVP), as a co-complexing agent, was innovatively used to modify DMC and applied to the synthesis of poly(ether–carbonate) polyols from CO 2 , PO, and a chain transfer agent. The modified catalysts exhibited higher catalytic activity than the catalysts prepared by conventional methods, with a nearly 10 % increase in PO conversion. The most critical breakthrough was a reduction of nearly 5 wt% in the byproduct propylene–carbonate. The results confirmed that amide groups in PVP could coordinate with active center Zn2+, providing the modified catalysts with advantages such as low-symmetry structure, high specific surface area, and strong acidity. Moreover, the dual effects of PVP coordination and dispersion led to dramatic differences in the microstructure and activity of the catalysts when added during different preparation processes of DMC. The coordination effect of PVP was dominant in the nucleation stages which affected the crystal structure and morphology, whereas, the dispersion effect was dominant in the aging stages which prevented the catalyst particles from growing and thus a higher specific surface area. This is critical for paving the way towards exploring the introduction of groups with high steric hindrance into Zn–Co complex catalysts. In addition, a detailed and in-depth insight into the structure–activity relationship of DMC for poly(ether–carbonate) polyols synthesis was summarized. [Display omitted] • Polyvinylpyrrolidone (PVP) was first used to modify double metal cyanide catalysts. • PVP added in different preparing stages affected crystal structure of the catalyst. • PVP-modified catalysts showed low symmetry, high surface area, and strong acidity. • N of PVP coordinated to Zn2+ helped to activate CO 2 and epoxide. • Modified catalysts showed higher activity and selectivity for CO 2 copolymerization. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A series of CO 2 derived amino-alcohol compounds were synthesized. • Structures of amino-alcohol compounds influenced the properties of adhesives. • PU adhesives from the synthesized amino-alcohol compounds showed excellent adhesion properties. • CO 2 derived adhesives showed other considerable properties. Abstract A series of novel amino-alcohol curing agents for PU adhesives were synthesized from CO 2 , glycidyl ether and diamine through carbonation and amination reactions. By physically evaluating the compounds through FT-IR and 1H NMR spectroscopy and mechanically analyzing the adhesives through T-peel strength tests, the raw materials have successfully been transformed into curing agents and the curing agents were found to endow the adhesives with specific structures and unique properties. For PVC bonding, compared to the traditional curing agents HDA and HDO, the T-peel strength and medium resistance from the novel amino-alcohol compounds improved. Further analysis revealed distinction in mechanical properties for different curing agents, the trifunctional curing agent exhibited the largest tensile strength and hardness. Moreover, thermal analysis of the adhesives demonstrated the considerable thermal stability to those prepared from HDA and HDO. [ABSTRACT FROM AUTHOR]

In this work, CO 2 was chemically fixed by reacting with 1, 4-butanediol diglycidyl ether in the presence of a basic polystyrene resin catalyst. Under the 100% conversion of 1, 4-butanediol diglycidyl ether, five-membered cyclocarbonate with a selectivity of 98.5% was obtained. The cyclocarbonate was then reacted with an excess of 1, 2-ethylenediamine and the product was characterized by Fourier transform infrared spectrometer and nuclear magnetic resonance spectrometer. The results confirmed the successful synthesis of NH 2 terminated product with a selectivity of 98.9%, accompanied by the formation of hydroxyls on β-C to the carbonyl groups, which can be regarded as a new amino-alcohol. Further, the obtained amino-alcohol was applied for the preparation of polyurethane urea as chain extender in a prepolymer way. Since the reactivity of isocyanate with NH 2 is much faster than that with OH, the OH groups can be maintained in the system and hence strengthen the hydrogen bonding in polyurethane urea, which endows the materials with some unique properties. Comparing with the polyurethanes yielded from 1, 6-hexanediamine and 1, 6-hexanediol, polyurethane urea synthesized from the new amino-alcohol possessed better water/solvents resistance, considerable mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

A five-membered cyclic carbonate as CO 2 -sourced monomer was prepared from ethylene glycol diglycidyl ether (EGDE) with CO 2 by cycloaddition reaction, abbreviated as 5CC-EGDE, at 130 ℃ under 10 bar CO 2 pressure in the presence of quaternary ammonium salt modified amberlyst (D296) for 20 h. The complete conversion and 98.6% selectivity were obtained, respectively. The incorporation of 5CC-EGDE into epoxy resin could reduce the viscosity during preparation process and improve the toughness effectively. It was ascribed to the ring-opening reaction of 5CC-EGDE with curing agent, and hydrogen bonding, formed between urethane groups and other polar groups. Besides, the low crosslinking density and unreacted carbonate groups remaining in epoxy network were beneficial to the movement of molecular chains and dissipation of energy during deformation process. In addition, effects of hydrogen-bonding interactions and crosslinking density on mechanical performances were also investigated by varying EGDE conversion and amount of added curing agent, respectively. The results indicated that mechanical performances of epoxy resin were promoted by combined effects of urethane linkage, hydrogen bonding, low crosslinking density and unreacted carbonate groups. [ABSTRACT FROM AUTHOR]

A series of hybrid polyhydroxyurethane (PHU) materials were prepared from CO 2 , polypropylene glycol diglycidyl ether, amines, and bisphenol-A diglycidyl ether (BADGE). Firstly, the five-membered cyclocarbonate (5CC) as the CO 2 -sourced monomer was synthesized by a cycloaddition reaction from CO 2 and polypropylene glycol diglycidyl ether at 120 °C under 10 bar CO 2 pressure in the presence of an amberlyst catalyst. The selectivity of 5CC was confirmed through an analog computation method based on the results of 1 H NMR. Then, 5CC was reacted with excessive amines to produce the −NH 2 terminated pre-polymers. Finally, the pre-polymers reacted with BADGE to produce hybrid PHU materials. The effect of amine type and BADGE content on the properties of PHUs was studied by means of Fourier transform infrared spectra, dynamic mechanical thermal analysis, and thermogravimetric analysis and solvent swelling test. The results indicated that introducing BADGE as a chain extender not only enhances the gelation rate of PHU, but also improve the mechanical and thermal properties of PHU materials. [ABSTRACT FROM AUTHOR]

A series of novel amino-alcohol compounds were synthesized from ethylenediamine and cyclic carbonates derived from different glycidyl ethers and CO 2. The amino-alcohols were applied as chain extender for the preparation of polyurethaneurea (PUU) containing hydroxyl groups. The influence of the amino-alcohols on the structure and property of PUU were studied by mechanical testing, Fourier transform infrared spectroscopy (FT-IR), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and thermogravimetry (TG) et. al. The tensile strength of hydroxyl contained polyurethaneurea CDMEDA-PUU could reach 28.27 MPa, about 260% higher than the hydroxyl shielded one. The results proved that the introduced hydroxyl groups greatly enhanced the hydrogen bonding within PUU and the structure of amino-alcohol had certain impact on PUU performance. The cyclic tensile test results further disclosed the existence of strong hydrogen bonding among the hard segments and the long-range connectivity of the permeable hard domains. • Five novel amino-alcohols with different structure derived from CO 2 were synthesized. • Hydroxyl groups were introduced into PUU by using amino-alcohols as chain extenders. • Hydrogen bonding in hydroxyl contained PUU was investigated. • A unique linear relationship between W and ΔW shown in the cyclic tensile tests was disclosed. • The long-range connectivity of the permeable hard domains is existed in hydroxyl contained PUU. [ABSTRACT FROM AUTHOR]