The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent mixtures.The performance of cu...The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent mixtures.The performance of currently available group contribution(GC)methods for HSP were evaluated and found to be insufficient for computer-aided product design(CAPD)of paints and coatings.A revised and,for this purpose,improved GC method is presented for estimating HSP of organic compounds,intended for organic pigments.Due to the significant limitations of GC methods,an uncertainty analysis and parameter confidence intervals are provided in order to better quantify the estimation accuracy of the proposed approach.Compared to other applicable GC methods,the prediction error is reduced significantly with average absolute errors of 0.45 MPa^(1/2),1.35 MPa^(1/2),and 1.09 MPa^(1/2) for the partial dispersion(δD),polar(δP)and hydrogen-bonding(δH)solubility parameters respectively for a database of 1106 compounds.The performance for organic pigments is comparable to the overall method performance,with higher average errors forδD and lower average errors forδP andδH.展开更多
Poly(vinylidene fluoride), PVDF, membranes have attracted considerable attention as polymer electrolytes for fuel cells. This study explores the effect of solvent on the spherulite size and the crystallinity of the po...Poly(vinylidene fluoride), PVDF, membranes have attracted considerable attention as polymer electrolytes for fuel cells. This study explores the effect of solvent on the spherulite size and the crystallinity of the polymeric membranes. Based on Hansen solubility parameters theory, the mixture of DMC and DMSO was selected among a dozen of solvents for the preparation of PVDF membranes by thermally induced phase separation. The addition of two protic ionic liquids(PILs), bis(2-ethyl hexyl) ammonium hydrogen phosphate [EHNH_2][H_2PO_4], and imidazolium hexanoate [Im][Hex] to PVDF membranes at concentrations(10% < wP IL< 50%) has been investigated by SEM, FTIR, DSC, TGA, EIS, and DMA. The inclusion of ionic liquids into the polymer matrix influences structural parameters(degree of crystallinity and electroactive phases), thermal stability, proton conductivity and mechanical properties of the membranes. The membranes become transparent regardless type of ionic liquid employed. A small amount of ionic liquids increases the degree of crystallinity and facilitates the production of polar β and γ crystals. The proton conductivity mechanism(Grotthuss) is dependent on the ionic liquid structure(due to its selforganization in water) and the content in the PVDF membrane, as well as the membrane water uptake.Different behavior has been observed for the two ionic liquids, which stresses the challenge on selecting an appropriate cation and anion combination. The obtained composite membranes exhibited excellent mechanical performance and reduced elastic modulus, with respect to the pure polymer matrix. These results indicate that PVDF/IL composite membranes have a high potential for PEMFC applications.展开更多
Doping lignin with carbon nanotubes is a promising strategy for cost-effective high-performance carbon fibers.We investigate the intermolecular interaction potential of CNT and organosolv lignin with two main approach...Doping lignin with carbon nanotubes is a promising strategy for cost-effective high-performance carbon fibers.We investigate the intermolecular interaction potential of CNT and organosolv lignin with two main approaches.Experimentally,oxidized purified multiwalled carbon nanotubes(MWCNTs)and beech organosolv lignins and derivatives are analyzed with their Hansen solubility parameters(HSPs)to assess their mutual compatibility.Theoretically,dispersion-corrected density functional theory simulations of the interaction between model molecules and single-walled carbon nanotubes reveal the source of interactions.We find that oxidation enables and enhances the interaction between carbon nanotubes and organosolv lignin experimentally,which is in agreement with the enhanced polar interaction found in the simulations.展开更多
Aseptic containers,widely known as Tetra Paks,are multi-layered packages used in the food industry.These shelf-stable containers preserve the freshness and taste of products,such as beverages,and simplify their distri...Aseptic containers,widely known as Tetra Paks,are multi-layered packages used in the food industry.These shelf-stable containers preserve the freshness and taste of products,such as beverages,and simplify their distribution and storage.However,the recycling of these packages is notoriously difficult and limited due to their multilayer structure,with recycling rates close to zero in many developing countries and rarely reaching 50%in industrialized nations.Nevertheless,various methods have been proposed to recycle such packages,including the recovery of paper through the hydropulping process and the separation of aluminum from plastic using solvents.The current study focuses on recycling the Al-PE composite residue after hydropulping.Nine solvents,namely xylene,toluene,ethanol,formic acid,distilled water,isopropyl alcohol,acetic acid,methanol,and ethyl acetate,were tested,and the percentage of polyethylene dissolution was determined for each.After identifying xylene and toluene as the most effective solvents,it was hypothesized for the first time that gasoline,a widely available solvent containing a high percentage of both xylene and toluene,could prove effective.Further investigations revealed that using the solvent mixture xylene:toluene:water(53:37:10,v/v)leads to 95%dissolution,while gasoline alone was 85%effective.Finally,Gas Chromatography-Mass Spectrometry(GC-MS)and Hansen Solubility Parameters(HSPs)were used to examine gasoline as a solvent more closely.The analyses showed that,in addition to BTEX,there are many constituents in gasoline that can aid the recycling process.展开更多
The development of an efficient pretreatment technology to depolymerize and fractionate lignocellulose into glucan,xylan,and lignin is crucial for lignocellulose biorefinery.In this study,alcohol pretreatments using m...The development of an efficient pretreatment technology to depolymerize and fractionate lignocellulose into glucan,xylan,and lignin is crucial for lignocellulose biorefinery.In this study,alcohol pretreatments using methanol and pentanol were developed and compared.Based on the solubility of the two alcohols,the methanol and pentanol pretreatments are homogeneous and biphasic,respectively.Carbon flow analysis revealed that 1 kg of corn stalk(CS)yielded 111.9 g of lignin with the homogeneous pretreatment(lignin yield:60.0%),while 149.8 g of lignin was obtained with the biphasic pretreatment(lignin yield:80.3%).Biphasic pretreatment yielded the lignin with higher activity(moreβ-O-4 bond content).Additionally,210.4 g and 267.0 g of glucose were obtained from the enzymatic hydrolysis of homogeneously and biphasically pretreated CS,respectively,where glucose yields were 53.0%and 67.2%,respectively.Fourier Transform infrared spectroscopy(FT-IR)and X-ray diffraction(XRD)were employed to verify the component fractionation results.The Hansen solubility parameter and combined severity factor analysis were used to evaluate the effects of various factors on component fractionation.Nuclear magnetic resonance and mechanistic analyses were performed to explore the process of component fractionation.Overall,we discovered that biphasic pretreatment was significantly better than homogeneous pretreatment in component fractionation,including component recovery and lignin activity.展开更多
基金Financial support from the Sino-Danish Center for Education and Research(SDC)the Hempel Foundation to CoaST(The Hempel Foundation Coatings Science and Technology Centre)Hempel A/S。
文摘The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent mixtures.The performance of currently available group contribution(GC)methods for HSP were evaluated and found to be insufficient for computer-aided product design(CAPD)of paints and coatings.A revised and,for this purpose,improved GC method is presented for estimating HSP of organic compounds,intended for organic pigments.Due to the significant limitations of GC methods,an uncertainty analysis and parameter confidence intervals are provided in order to better quantify the estimation accuracy of the proposed approach.Compared to other applicable GC methods,the prediction error is reduced significantly with average absolute errors of 0.45 MPa^(1/2),1.35 MPa^(1/2),and 1.09 MPa^(1/2) for the partial dispersion(δD),polar(δP)and hydrogen-bonding(δH)solubility parameters respectively for a database of 1106 compounds.The performance for organic pigments is comparable to the overall method performance,with higher average errors forδD and lower average errors forδP andδH.
基金“La region Centre Val de Loire” for financial support to the researchers involved in this study under “Lavoisier II” regional program。
文摘Poly(vinylidene fluoride), PVDF, membranes have attracted considerable attention as polymer electrolytes for fuel cells. This study explores the effect of solvent on the spherulite size and the crystallinity of the polymeric membranes. Based on Hansen solubility parameters theory, the mixture of DMC and DMSO was selected among a dozen of solvents for the preparation of PVDF membranes by thermally induced phase separation. The addition of two protic ionic liquids(PILs), bis(2-ethyl hexyl) ammonium hydrogen phosphate [EHNH_2][H_2PO_4], and imidazolium hexanoate [Im][Hex] to PVDF membranes at concentrations(10% < wP IL< 50%) has been investigated by SEM, FTIR, DSC, TGA, EIS, and DMA. The inclusion of ionic liquids into the polymer matrix influences structural parameters(degree of crystallinity and electroactive phases), thermal stability, proton conductivity and mechanical properties of the membranes. The membranes become transparent regardless type of ionic liquid employed. A small amount of ionic liquids increases the degree of crystallinity and facilitates the production of polar β and γ crystals. The proton conductivity mechanism(Grotthuss) is dependent on the ionic liquid structure(due to its selforganization in water) and the content in the PVDF membrane, as well as the membrane water uptake.Different behavior has been observed for the two ionic liquids, which stresses the challenge on selecting an appropriate cation and anion combination. The obtained composite membranes exhibited excellent mechanical performance and reduced elastic modulus, with respect to the pure polymer matrix. These results indicate that PVDF/IL composite membranes have a high potential for PEMFC applications.
文摘Doping lignin with carbon nanotubes is a promising strategy for cost-effective high-performance carbon fibers.We investigate the intermolecular interaction potential of CNT and organosolv lignin with two main approaches.Experimentally,oxidized purified multiwalled carbon nanotubes(MWCNTs)and beech organosolv lignins and derivatives are analyzed with their Hansen solubility parameters(HSPs)to assess their mutual compatibility.Theoretically,dispersion-corrected density functional theory simulations of the interaction between model molecules and single-walled carbon nanotubes reveal the source of interactions.We find that oxidation enables and enhances the interaction between carbon nanotubes and organosolv lignin experimentally,which is in agreement with the enhanced polar interaction found in the simulations.
文摘Aseptic containers,widely known as Tetra Paks,are multi-layered packages used in the food industry.These shelf-stable containers preserve the freshness and taste of products,such as beverages,and simplify their distribution and storage.However,the recycling of these packages is notoriously difficult and limited due to their multilayer structure,with recycling rates close to zero in many developing countries and rarely reaching 50%in industrialized nations.Nevertheless,various methods have been proposed to recycle such packages,including the recovery of paper through the hydropulping process and the separation of aluminum from plastic using solvents.The current study focuses on recycling the Al-PE composite residue after hydropulping.Nine solvents,namely xylene,toluene,ethanol,formic acid,distilled water,isopropyl alcohol,acetic acid,methanol,and ethyl acetate,were tested,and the percentage of polyethylene dissolution was determined for each.After identifying xylene and toluene as the most effective solvents,it was hypothesized for the first time that gasoline,a widely available solvent containing a high percentage of both xylene and toluene,could prove effective.Further investigations revealed that using the solvent mixture xylene:toluene:water(53:37:10,v/v)leads to 95%dissolution,while gasoline alone was 85%effective.Finally,Gas Chromatography-Mass Spectrometry(GC-MS)and Hansen Solubility Parameters(HSPs)were used to examine gasoline as a solvent more closely.The analyses showed that,in addition to BTEX,there are many constituents in gasoline that can aid the recycling process.
基金funded by the National Natural Science Foundation of China(22361132543,22378391,52206286 and 21978288)Youth Talent Program of Xi’an Talent Plan(XAYCQN21002)。
文摘The development of an efficient pretreatment technology to depolymerize and fractionate lignocellulose into glucan,xylan,and lignin is crucial for lignocellulose biorefinery.In this study,alcohol pretreatments using methanol and pentanol were developed and compared.Based on the solubility of the two alcohols,the methanol and pentanol pretreatments are homogeneous and biphasic,respectively.Carbon flow analysis revealed that 1 kg of corn stalk(CS)yielded 111.9 g of lignin with the homogeneous pretreatment(lignin yield:60.0%),while 149.8 g of lignin was obtained with the biphasic pretreatment(lignin yield:80.3%).Biphasic pretreatment yielded the lignin with higher activity(moreβ-O-4 bond content).Additionally,210.4 g and 267.0 g of glucose were obtained from the enzymatic hydrolysis of homogeneously and biphasically pretreated CS,respectively,where glucose yields were 53.0%and 67.2%,respectively.Fourier Transform infrared spectroscopy(FT-IR)and X-ray diffraction(XRD)were employed to verify the component fractionation results.The Hansen solubility parameter and combined severity factor analysis were used to evaluate the effects of various factors on component fractionation.Nuclear magnetic resonance and mechanistic analyses were performed to explore the process of component fractionation.Overall,we discovered that biphasic pretreatment was significantly better than homogeneous pretreatment in component fractionation,including component recovery and lignin activity.
