Polyurethane/epoxy hybrid materials from CO2-sourced monomer were prepared via an environmentally-friendly and non-toxic route, which avioded the use of toxic isocyanate. A series of non-isocyanate polyurethane (NIPU)/epoxy hybrid materials, with different and controlled architectures, were synthesized from CO2, polypropylene glycol diglycidyl ether (PPGDGE), amines and diglycidyl ether of bisphenol-A (BADGE). Around 12 wt% CO2 was incorporated into PPGDGE to form a five-membered cyclic carbonate (5CC-PPGDGE). The complete conversion and selectivity of PPGDGE were obtained. The kinetics of 5CC-PPGDGE was investigated by reacting it with 1,2-ethylenediamine (EDA) at different temperatures. NH2-terminated pre-polymers were obtained by reacting 5CC-PPGDGE with various excessive amines. Finally, the hybrid materials were obtained by curing pre-polymers with BADGE. The results showed that a high content of amine with more functional groups led to better mechanical performances than diamine-based hybrid materials. This is the first time that architectures have been controlled by altering the amine ratio and functionality. And these hybrid materials exhibited satisfactory mechanical performances. The DETA-based and TETA-based materials with high amine ratio exhibited a tensile strength of 15.0 MPa and 12.5 MPa, accompanied with elongation at break of 151.3% and 170.9%, respectively. The gel content, glass transition temperature and thermodynamic stability went up first and then declined with the increase of amine ratio, which demonstrated the architectures of hybrid materials ranged from defective to cross-linked and linear structures.

Hydrogenolysis of glucose and cellobiose, used as the model feedstocks, over Ni–WO3/SBA-15 catalysts has been investigated to probe the influencing factors for the conversion of cellulose to ethylene glycol (EG). The conversion of glucose and cellobiose to EG showed different dependencies on reaction temperature; a lower reaction temperature was needed for the former. Additionally, the surface atomic ratio of W to Ni on the Ni–WO3/SBA-15 catalysts was the key factor for the product distribution. Both glucose and cellobiose had their own optimum W–Ni ratio for the production of EG, and the ratio of W to Ni for glucose was slightly lower than that of cellobiose. On the other hand, the Ni–WO3/SBA-15 catalysts were thoroughly characterized by N2 adsorption–desorption, X-ray diffraction (XRD), hydrogen-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results indicated that the reducibility of Ni–WO3/SBA-15 catalysts with high Ni loading was more similar to that of pure NiO. More importantly, the change of surface atomic content of Ni and W of Ni–WO3 catalysts with various Ni loadings resulted from the surface W species of the catalysts being gradually covered by Ni species with the increase of Ni loading.

•Waterborne polyurethanes are synthesized from 4 different polycarbonatediols.•WPUs show different properties as molecular weight and structure of PCDL varies.•The emulsions with nanoparticles display excellent stability.•Polyurethanes have much better properties as molecular weight of PCDL increases.•Homopolymer-based polyurethanes have superior thermal and mechanical properties.A series of waterborne polyurethanes (WPUs) were synthesized by a pre-polymer process from isophorone diisocyanate, 1,6-hexamethylene diisocyanate and polycarbonatediol with varying molecular weight (1000–2000 Da) and molecular structure (copolycarbonate and homopolycarbonate). The effect of polycarbonatediols on the performance of the emulsion was studied by means of apparent viscosity, particle size distribution and Zeta potential analysis. Fourier transform infrared spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, X-ray diffraction, dynamic mechanical analysis, physical and mechanical measurements and water droplet contact angle tests were employed to characterize the thermal stability, crystallinity, low temperature flexibility, physical and mechanical properties and wettability of the films derived from the emulsions. The results indicated that WPU dispersions with mean particle size in the range of 50–70 nm and Zeta potential value about −50 mV displayed excellent storage stability. It was found that the mean particle size, thermal stability, crystallinity, low temperature flexibility, mechanical properties and hydrophobicity increased and the particle distribution decreased with the increase of molecular weight of the polycarbonatediols. Moreover, copolycarbonate-based WPUs showed higher crystallinity of hard segments, thermal stability and wettability than the homopolycarbonate-based ones.

•Up to 70.7% ethylene glycol yield was obtained over 3%Ni–15%WO3/SBA-15 catalyst.•A strong electronic interaction between NiO and WO3 in the catalyst was found.•The real active species for the selective cleavage of CC bond was studied.•A possible mechanism of conversion cellulose into ethylene glycol was proposed.Ni–WO3/SBA-15 catalysts were prepared by an impregnation way and applied to the hydrogenolysis of cellulose in aqueous solution. The effect of nickel and WO3 loading, catalysts reduction temperature and time on cellulose conversion were investigated. Up to 70.7% ethylene glycol yield was obtained over 3%Ni–15%WO3/SBA-15 catalysts. Several physicochemical methods such as XRD, Raman spectroscopy, NH3-TPD, H2-TPR and XPS were used to determine the character of catalysts. Based on these studies, it was found that there was a strong electronic interaction between NiO and WO3, which not only promoted the reduction of WO3, but restrained the reduction of NiO. Together with the experimental results, it can be concluded that the WO3−X, which may be the active species for the selective cleavage of CC bond, was formed after catalysts pretreatment process. Additionally, a possible catalytic mechanism was proposed.

Glucose and cellobiose were used as model compounds to investigate the effect of retro-aldol condensation and hydrogenation rates on the product distribution of cellulose conversion. It was shown that the product distribution obtained over the physical mixture of Ni/SBA-15 and WO3/SBA-15 in the glucose and cellobiose conversions were different from that attained on the Ni-WO3/SBA-15 prepared by the co-impregnation method. The ethylene glycol (EG) yield depended on the structures of tungstic compounds, and it increased in the order of WO3 < WO3/SBA-15 < (NH4)6W7O24·6H2O (AMT), while the particle sizes of them decreased in such an order. Regardless of the types of tungstic compounds, the EG yield obtained in the glucose conversion is lower than that attained in the cellobiose conversion at the same amount of catalyst.

•CO2-sourced monomer was synthesized by a cycloaddition reaction from CO2 and polypropylene glycol diglycidyl ether.•The selectivity of formed cyclocarbonate was acquired through mathematical simulation calculation method from the results of 1H NMR.•−NH2 terminated pre-polymers were synthesized.•The hybrid PHU materials were synthesized from the reaction of pre-polymer and BADGE.•The effect of amine ratio, type and BADGE content on the properties of PHUs was studied.A series of hybrid polyhydroxyurethane (PHU) materials were prepared from CO2, polypropylene glycol diglycidyl ether, amines, and bisphenol-A diglycidyl ether (BADGE). Firstly, the five-membered cyclocarbonate (5CC) as the CO2-sourced monomer was synthesized by a cycloaddition reaction from CO2 and polypropylene glycol diglycidyl ether at 120 °C under 10 bar CO2 pressure in the presence of an amberlyst catalyst. The selectivity of 5CC was confirmed through an analog computation method based on the results of 1H NMR. Then, 5CC was reacted with excessive amines to produce the −NH2 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.Download high-res image (74KB)Download full-size imageWe successfully synthesized hybrid PHU materials from CO2, PPGDGE, amines, and BADGE through three steps process. The CO2-sourced monomer was synthesized by the coupling reaction of CO2 with PPGDGE. The −NH2 pre-polymers were obtained by the ring-opening of CO2-sourced monomer with amine, and pre-polymers reacted with corresponding content BADGE to produce hybrid PHUs through compression molding.

Series of non-precious metal catalysts Ni-WO3/SBA-15 were prepared by means of incipient impregnation and applied to the hydrogenolysis of cellulose in aqueous solution. The effect of reaction temperature on the hydrolysis and morphology of cellulose, and the influence of Ni, WO3 loading on the conversion of cellulose were investigated. High crystalline cellulose was transformed gradually into amorphous state with the increase of reaction temperature. H2 temperature program reduction of the catalyst proved that a strong interaction existed between nickel and tungsten trioxide, which enhanced the ability of tungsten species to the cleavage of C-C bond and the activity of hydrogenation of nickel. Thus, the transformation of cellulose into ethylene glycol was strengthened markedly. The complete conversion of cellulose and 70.7% ethylene glycol yield were obtained over a 3% Ni-15% WO3/SBA-15 catalyst under the reaction condition of 230°C and 6.0 MPa H2 for 6.0 h.