A series of novel fluorine-containing acrylates 6a-6g were synthesized via the condensation of ethyl cyanoacetate and trifluoroacetic anhydride, followed by chloridization and the coupling reaction with amines. These ...A series of novel fluorine-containing acrylates 6a-6g were synthesized via the condensation of ethyl cyanoacetate and trifluoroacetic anhydride, followed by chloridization and the coupling reaction with amines. These new compounds exhibited some biological activity as preliminary bioassay indicated. A plausible reaction mechanism was outlined and discussed.展开更多
Introduction The emulsion of acrylate copolymers with actively functional groups have been widely developed and used as coating, adhesive and handling agent in spinning and weaving industry. Bessett, D. R. et al. stud...Introduction The emulsion of acrylate copolymers with actively functional groups have been widely developed and used as coating, adhesive and handling agent in spinning and weaving industry. Bessett, D. R. et al. studied the thermoset of N-(isobutoxymethyl) acrylamide by thermal evolution analysis and thermal gas chromatogram. Krejcar,展开更多
Two new C2-symmetrical bidentate phosphoramidite ligands were synthesized and employed in the Rh-catalyzed asymmetric hydrogenation of β-（acylamino）acrylates, up to 89% ee with full conversions was obtained.
Two kinds of UV curable polyurethane acrylate oligomers （PUPA and PUCA） were synthesized via the addition reaction between isophorone diisocyanate （IPDI） and polyethylene glycol monoacrylate （PEA6） or polycaprol...Two kinds of UV curable polyurethane acrylate oligomers （PUPA and PUCA） were synthesized via the addition reaction between isophorone diisocyanate （IPDI） and polyethylene glycol monoacrylate （PEA6） or polycaprolactone modified hydroxyethyl acrylate （PCLA2）. The structures of PUPA and PUCA were characterized by Fourier transform infrared spectroscopy （FT-IR）, IH nuclear magnetic resonance （^H NMR）, gel permeation chromatography （GPC） and differential scanning calorimeter （DSC）, and the thermal stability and dynamic mechanical thermal properties of their cured films were measured by thermogravimetric analysis （TGA） and dynamic mechanical analysis （DMA）, respectively. The viscosity of the oligomers and mechanical properties of the cured films were also studied. The results show that both oligomers have narrow molecular weight distribution. The viscosity of PUPA is 2.310 Pa.s at 25 ℃, while that of PUCA is： up to 3.980 Pa-s. The UV cured PUPA and PUCA films have homogeneous phase structure, and the PUCA film shows higher glass transition temperature and storage modulus. Furthermore, the PUCA film possesses better mechanical properties than PUPA, while the latter shows better alkali resistance.展开更多
The production of acrylates from biomass-originated lactic acid is of extraordinary importance, to overcome the increasing worldwide shortage of petroleum. In this study, the catalytic dehydration of methyl lactate ov...The production of acrylates from biomass-originated lactic acid is of extraordinary importance, to overcome the increasing worldwide shortage of petroleum. In this study, the catalytic dehydration of methyl lactate over a calcium sulfate catalyst, with various promoters, has been carried out to identify potential catalyst/promoter combinations for acrylate production. The best catalyst for methyl acrylate formation in this study has been calcium sulfate, with cupric sulfate and phosphates as promoters. The optimal mass ratio of m（CaSOa） ： m（CuSOa） ： m（Na2HPO4） ： m（KH2PO4） is 150.0 ： 13.8 ： 2.5 ： 1.2. Effects of carrier gas, reaction temperature, feed concentration as well as contact time on the dehydration of methyl lactate have been investigated. With nitrogen as a carrier gas, a combined yield of acrylic acid and methyl acrylate is 63.9% from 60% （by mass） methyl lactate at 400℃ with 7.7 seconds contact time.展开更多
Three kinds of UV-curable self-emulsified polyurethane-acrylate (PUA) prepolymer, i.e., conventional, chain extended and grafted PUAs, were prepared. The relatively small particle size of the PUA dispersions indicates...Three kinds of UV-curable self-emulsified polyurethane-acrylate (PUA) prepolymer, i.e., conventional, chain extended and grafted PUAs, were prepared. The relatively small particle size of the PUA dispersions indicates that the PUA prepolymers exhibit sufficient aqueous dispersibility. The PUA prepolymers can substantially lower the interfacial tension of water. Chain-extended PUA dispersions exhibit pseudoplastic behavior and thixotropy to a greater extent than do their conventional counterpart. The chain-extended and grafted PUA photocure to higher conversion than do the conventional PU equivalent. The results of DSC measurement suggest that there exists phase mixing between the hard and the soft segment phases for the PUAs based on PEG 400 that is the comparatively short soft segment in the prepolymer. For the PUA prepolymers based on PEG having higher M-n values, chain-extending and grafting could impede the phase separation between the hard and the soft segment domains. The adhesion, impact strength and flexibility of the photocured films were tested.展开更多
Cyclic acrylates, 2,2- dimethyl-5-methylene-1 , 3-dioxolan-4 -one and 2- phenyl-5-methylene-1,3-dioxolan-4-one, were synthesized successfully. The monomers were characterized by ~1H NMR, ^(13)C NMR, IR and elemental a...Cyclic acrylates, 2,2- dimethyl-5-methylene-1 , 3-dioxolan-4 -one and 2- phenyl-5-methylene-1,3-dioxolan-4-one, were synthesized successfully. The monomers were characterized by ~1H NMR, ^(13)C NMR, IR and elemental analysis or HRMS. Polymerization of the monomers were carried out at 120℃ with di-t-butylperoxide as initiator. The polymers were studied by ~1H NMR, ^(13)C NMR, UV and hydrolysis. The molecular weights of the resulting polymers were estimated by viscosity measurement and the extent of ring opening was estimated also by ~1H NMR and hydrolysis of the polymers and further confirmed by UV spectra.展开更多
The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate (HOPA) and acrylic acid (AA) was used to prepare th...The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate (HOPA) and acrylic acid (AA) was used to prepare the acrylic latexes with high-solid content. The effects of monomer emulsion feed rates (R(a)) and (R/E)(E) values, the ratio of emulsifier amount between the initial charge (R) and the addition monomer emulsion (E), on the polymerization reaction features, the viscosities, surface tensions,particle sizes and particle sizes distributions of latexes, T-g and the insoluble fractions of films, the 180 degrees peel strength, tack and holding power of pressure-sensitive adhesive (PSA) tapes, prepared from the latexes, were studied. Experimental study shows that the grafting and crosslinking fraction in the PSA tapes must be controlled within a suitable range to keep the balance of the 180 degrees peel strength, tack and holding power.展开更多
A simple and effective way to prepare poly（acrylate）s, such as poly（methacrylate）, poly（butyl acrylate） and poly（butyl methacrylate）, has been achieved by using the single component aluminum-based compounds, s...A simple and effective way to prepare poly（acrylate）s, such as poly（methacrylate）, poly（butyl acrylate） and poly（butyl methacrylate）, has been achieved by using the single component aluminum-based compounds, such as modified methylaluminoxane （MMAO）, triisobutylaluminium （TIBA） and triethylaluminium （TEA） as initiators. Effective initiations and high molecular weight polymers with unimodal molecular weight distributions could be easily obtained by varying the reaction parameters of systems under mild conditions. Although these aluminum compounds were inefficient initiators for methyl methacrylate （MMA） polymerization, they exhibited remarkable catalytic activity for butyl methacrylate （BMA） polymerization, affording high molecular weight poly（BMA）s.展开更多
Molecular modeling of acrylates (acrylamides) with D1 protein of Pisum sativum is presented. Studies show that the binding force mainly includes H-bond interaction, Van der Waals and π-ring stacking interaction. It w...Molecular modeling of acrylates (acrylamides) with D1 protein of Pisum sativum is presented. Studies show that the binding force mainly includes H-bond interaction, Van der Waals and π-ring stacking interaction. It was found that SER 268 in Dl protein might be an important binding site. It is important for high inhibitory activity of compounds whether an electronegative atom in alkyl of ester linkage could make H-bond interaction with SER 268 in Dl protein. Thus some new acrylates (acrylamides) were designed and synthesized, Bioassay indicated that these new compounds showed expected Hill reaction inhibitory activity.展开更多
A direct three-component approach has been developed for the synthesis of a-cyano acrylates starting from al- dehydes, alcohols and a-cyano acetamide by employing cyanuric chloride as an organocatalyst. A class of str...A direct three-component approach has been developed for the synthesis of a-cyano acrylates starting from al- dehydes, alcohols and a-cyano acetamide by employing cyanuric chloride as an organocatalyst. A class of structur- ally diverse a-cyano acrylates have been provided with good to excellent yields via the cascade transformation of Knoevenagel condensation and amide esterification.展开更多
In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadeq...In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadequate post-cure toughness,which compromise fatigue resistance during service.To address these issues,we synthesized hydroxyl-terminated polyurethane acrylate prepolymers using diphenylmethane diisocyanate(MDI),polypropylene glycol(PPG),and hydroxyethyl methacrylate(HEMA).Fourier transform infrared spectroscopy(FTIR)confirmed successful prepolymer synthesis.We developed UV-curable resins by incorporating various crosslinking monomers and optimized the formulations through mechanical property analysis.Testing revealed that the polyurethane-acrylic UV-cured resin system combines polyurethane's mechanical excellence with acrylics'high UV-curing activity.The PPG200/MDI/HEMA formulation achieved superior performance,with a tensile strength of 55.31 MPa,an impact toughness of 22.7 kJ/m^(2),and a heat deflection temperature(HDT)of 132℃.The optimized system eliminates volatile components while maintaining high reactivity,addressing critical limitations in trenchless pipeline rehabilitation.The improved mechanical properties meet the operational demands of underground pipes,suggesting practical applicability in trenchless pipeline repair.展开更多
The one-pot sequential reaction of arylamines, methyl propiolate and 2-aryl-3-nitrochromenes without any catalyst in refluxing ethanol afforded the polysubstituted 3-（3-nitro-2-phenylchroman-4-yl）-3-arylaminoacrylat...The one-pot sequential reaction of arylamines, methyl propiolate and 2-aryl-3-nitrochromenes without any catalyst in refluxing ethanol afforded the polysubstituted 3-（3-nitro-2-phenylchroman-4-yl）-3-arylaminoacrylates in good yields and with high diastereoselectivity. Reaction mechanism was believed involving the initial formation of β-enamino ester and sequential Michael addition.展开更多
The functionalized arylidene bis（3-arylaminoacrylates） were efficiently prepared by FeCl3 catalyzed one-pot domino reactions of primary amines, methyl propiolate and aromatic aldehydes. When isatins were utilized un...The functionalized arylidene bis（3-arylaminoacrylates） were efficiently prepared by FeCl3 catalyzed one-pot domino reactions of primary amines, methyl propiolate and aromatic aldehydes. When isatins were utilized under similar conditions, only 2-oxoindolinyl 3-arylaminoacrylates were obtained in moderate yields. ^1H NMR data and single crystal structures indicated that this reaction has high diastereoselectivity.展开更多
Synergy strategy of photocatalysts and polymer resins are promising technology for marine antifouling.However,it is still a main challenge to obtain a green,safe,and efficient antifouling coatings.Herein,carbon(graphe...Synergy strategy of photocatalysts and polymer resins are promising technology for marine antifouling.However,it is still a main challenge to obtain a green,safe,and efficient antifouling coatings.Herein,carbon(graphene or CNT)modified Ti O_(2)photocatalyst was synthesized via hydrothermal and annealing process and has successfully applied in acrylate fluoroboron polymer(ABFP)composite coating.Morphology and chemical composition were detailed characterized.The graphene or CNT acted as a bridge with supplemental spatial structures(petal gaps,entanglement)and new functional groups(C-O,C-Ti-O,etc.)on Ti O_(2)particle.Carbon nanotube(CNT)modified TiO_(2)-ABFP coatings(BTCP)achieved excellent antibacterial and anti-diatom adhesion rate of 89.3%-96.70%and 99.00%-99.50%,which was 1.84-4.94-fold more than that of the single ABFP.CNT or graphene served as electronic bridges was considered as the crucial mechanism,which significantly improved the light absorption range and capacity,conductivity,and photoelectric response of Ti O_(2),and further accelerated the generation and transfer of free radicals to the surface of BTCP or FTGP.Moreover,the improvement of catalyst activity synergizes with the smooth surface,hydrophilicity,and slow hydrolysis of composite coatings,achieved long-term and efficient antifouling performance.This work provides a new insight into the modification of Ti O_(2)and antifouling mechanism of polymer coating.展开更多
A novel composite material,Poly(IL-AA)@MIL-101(Cr),combining metal-organic framework,polymeric ionic liquid and acrylic acid,was synthesized for the selective and efficient adsorption of rare earths europium(Ⅲ)(Eu3+)...A novel composite material,Poly(IL-AA)@MIL-101(Cr),combining metal-organic framework,polymeric ionic liquid and acrylic acid,was synthesized for the selective and efficient adsorption of rare earths europium(Ⅲ)(Eu3+).Characterization of the materials was carried out using techniques such as X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS),thermogravimetric analysis(TGA)and Brunauer-Emmett-Teller(BET).The results demonstrate successful incorporation of the polymeric ionic liquid onto the material surface while preserving the crystal structure and mo rphology of MIL-101(Cr).Adsorption experiments were conducted to explore parameters including equilibrium pH,initial Eu3+concentration,and duration,with comprehensive analyses of adsorption kinetics,isotherms,and mechanisms.Findings reveal that Poly(IL1-AA)@MIL-101(Cr),Poly(IL3-AA)@MIL-101(Cr),and Poly(IL5-AA)@MIL-101(Cr)achieve adsorption equilibrium for Eu3+at approximately 9 h with an equilibrium pH of 6.2.The adso rption of Eu^(3+)predominantly follows a pseudo-second-order kinetic model and Langmuir isotherm adsorption model.Moreover,the prepared composite material exhibits superior adsorption selectivity for Eu^(3+)over other metal ions in the mixture(K^(+),Mg^(2+),Ni^(2+),Co^(2+),Zn^(2+),La^(3+),and Nd^(3+)).Even after five adsorption-desorption cycles,the composite material maintains satis factory adsorption performance.展开更多
Modified activated carbons(AS)were fabricated through the oxidation effect of ammonium persulfate and applied to the dynamic adsorption of different acrylate gas.The pore structures,surface chemical properties and sur...Modified activated carbons(AS)were fabricated through the oxidation effect of ammonium persulfate and applied to the dynamic adsorption of different acrylate gas.The pore structures,surface chemical properties and surface morphology of AS were respectively characterized by N2 adsorption,Boehm titration,X-ray Photoelectron Spectroscopy(XPS)and scanning electron microscopy(SEM)techniques.After modification,the specific surface area increased from 954 to 1154 m^(2)·g^(-1).The contents of oxygen-containing functional groups on the AS surface increase obviously and have a great effect on the adsorption behavior of acrylate gases.According to the results of dynamic adsorption,the adsorption capacities of acrylates are as the following order:methyl acrylate(461.9 mg·g^(-1))>methyl methacrylate(436.9 mg·g^(-1))>butyl acrylate(381.8 mg·g^(-1)),which is attributed to the size adaptability of AS pores and acrylates.The adsorption behavior of AS for acrylate gases conforms to the Bangham model and the Temkin model.展开更多
Flexible wearable electronic devices based on hydrogels have immense potential in a wide range of applications.However,many existing strain sensors suffer from significant limitations including poor mechanical propert...Flexible wearable electronic devices based on hydrogels have immense potential in a wide range of applications.However,many existing strain sensors suffer from significant limitations including poor mechanical properties,low adhesion,and insufficient conductivity.To address these challenges,this study successfully developed an organic-inorganic double-network conductive hydrogel using acrylic-modified bentonite (AABT) as a key component.The incorporation of AABT significantly enhanced the mechanical properties of the ATHG@LiCl hydrogel,achieving an impressive stretchability of 4000% and tensile strength of 250 kPa.Moreover,it improved the electrical conductivity of the hydrogel to a maximum of 1.53 mS/cm.The catechol structure of tannic acid (TA) further augmented the adhesive properties of the ATHG@LiCl hydrogel toward various substrates such as copper,iron,glass,plastic,wood,and pigskin.The addition of lithium chloride (LiCl) and dimethyl sulfoxide(DMSO) endowed the hydrogel with exceptional freezing resistance and flexibility,even at low temperatures of-20℃.Remarkably,the hydrogel maintained a conductivity of 0.53 mS/cm under these conditions,surpassing the performance of many other reported hydrogels.Furthermore,the ATHG@LiCl hydrogel demonstrated outstanding characteristics,such as high sensitivity (gauge factor GF=4.50),excellent transparency (90%),and reliable strain-sensing capabilities,indicating that the ATHG@LiCl hydrogel is a highly promising candidate for flexible wearable soft materials,offering significant advancements in both functionality and performance.展开更多
Vanadium phosphorus oxide(VPO)catalyst is a promising candidate for the condensation reaction of formaldehyde(FA)and acetic acid(HAc)to produce acrylic acid(AA).However,the complexity of the active phases and their dy...Vanadium phosphorus oxide(VPO)catalyst is a promising candidate for the condensation reaction of formaldehyde(FA)and acetic acid(HAc)to produce acrylic acid(AA).However,the complexity of the active phases and their dynamic interconversion under redox conditions has led to controversies regarding the actual active phase in this reaction.To address this,this study systematically investigates the phase transition and underlying mechanism of VPO catalysts under reaction conditions.X-ray diffraction(XRD)patterns,Raman spectra,transmission electron microscopy images and X-ray photoelectron spectroscopy collectively demonstrated that the V^(4+)phase(VO)_(2)P_(2)O_(7)retained the bulk phase structure throughout the reaction,with only minor surface phase transition observed.In contrast,the V^(5+)phase underwent reduction to other phases in both bulk and surface regions.Specifically,theδ-VOPO_(4)phase rapidly transformed into theαII-VOPO_(4)phase,which could reversibly convert into the R1-VOHPO_(4)phase(V^(4+)).Controlled variable experiments,H_(2)-temperature programmed reduction and in-situ XRD experiments in a hydrogen atmosphere further demonstrated that these phase transitions were primarily attributed to the loss of lattice oxygen.The presence of V^(4+)phase in VPO catalysts enhanced the selectivity of acrylic acid,while the existence of V^(5+)phase promoted the activation of acetic acid.This work elucidates the redox-driven phase evolution of VPO catalysts and offers valuable insights for designing efficient catalysts for FA-HAc cross-condensation by balancing phase stability and activity.展开更多
基金The project supported by the National Natural Science Foundation of China(No.2017203 1)the Chinese Research Fund for the Doctoral Pr ogram of High Education.
文摘A series of novel fluorine-containing acrylates 6a-6g were synthesized via the condensation of ethyl cyanoacetate and trifluoroacetic anhydride, followed by chloridization and the coupling reaction with amines. These new compounds exhibited some biological activity as preliminary bioassay indicated. A plausible reaction mechanism was outlined and discussed.
文摘Introduction The emulsion of acrylate copolymers with actively functional groups have been widely developed and used as coating, adhesive and handling agent in spinning and weaving industry. Bessett, D. R. et al. studied the thermoset of N-(isobutoxymethyl) acrylamide by thermal evolution analysis and thermal gas chromatogram. Krejcar,
基金The authors would like to thank the National Natural Science Foundation of China （No. 20472083） for financial support of this work.
文摘Two new C2-symmetrical bidentate phosphoramidite ligands were synthesized and employed in the Rh-catalyzed asymmetric hydrogenation of β-（acylamino）acrylates, up to 89% ee with full conversions was obtained.
基金Project(2007168303) supported by Guangdong-Hong Kong Technology Cooperation Funding
文摘Two kinds of UV curable polyurethane acrylate oligomers （PUPA and PUCA） were synthesized via the addition reaction between isophorone diisocyanate （IPDI） and polyethylene glycol monoacrylate （PEA6） or polycaprolactone modified hydroxyethyl acrylate （PCLA2）. The structures of PUPA and PUCA were characterized by Fourier transform infrared spectroscopy （FT-IR）, IH nuclear magnetic resonance （^H NMR）, gel permeation chromatography （GPC） and differential scanning calorimeter （DSC）, and the thermal stability and dynamic mechanical thermal properties of their cured films were measured by thermogravimetric analysis （TGA） and dynamic mechanical analysis （DMA）, respectively. The viscosity of the oligomers and mechanical properties of the cured films were also studied. The results show that both oligomers have narrow molecular weight distribution. The viscosity of PUPA is 2.310 Pa.s at 25 ℃, while that of PUCA is： up to 3.980 Pa-s. The UV cured PUPA and PUCA films have homogeneous phase structure, and the PUCA film shows higher glass transition temperature and storage modulus. Furthermore, the PUCA film possesses better mechanical properties than PUPA, while the latter shows better alkali resistance.
基金he Special Foundation for State Major Basic Research Program of China(2007CB707805,2004CCA05500)
文摘The production of acrylates from biomass-originated lactic acid is of extraordinary importance, to overcome the increasing worldwide shortage of petroleum. In this study, the catalytic dehydration of methyl lactate over a calcium sulfate catalyst, with various promoters, has been carried out to identify potential catalyst/promoter combinations for acrylate production. The best catalyst for methyl acrylate formation in this study has been calcium sulfate, with cupric sulfate and phosphates as promoters. The optimal mass ratio of m（CaSOa） ： m（CuSOa） ： m（Na2HPO4） ： m（KH2PO4） is 150.0 ： 13.8 ： 2.5 ： 1.2. Effects of carrier gas, reaction temperature, feed concentration as well as contact time on the dehydration of methyl lactate have been investigated. With nitrogen as a carrier gas, a combined yield of acrylic acid and methyl acrylate is 63.9% from 60% （by mass） methyl lactate at 400℃ with 7.7 seconds contact time.
基金Project supported by Guangdong Natural Science Foundation(No. 960019)
文摘Three kinds of UV-curable self-emulsified polyurethane-acrylate (PUA) prepolymer, i.e., conventional, chain extended and grafted PUAs, were prepared. The relatively small particle size of the PUA dispersions indicates that the PUA prepolymers exhibit sufficient aqueous dispersibility. The PUA prepolymers can substantially lower the interfacial tension of water. Chain-extended PUA dispersions exhibit pseudoplastic behavior and thixotropy to a greater extent than do their conventional counterpart. The chain-extended and grafted PUA photocure to higher conversion than do the conventional PU equivalent. The results of DSC measurement suggest that there exists phase mixing between the hard and the soft segment phases for the PUAs based on PEG 400 that is the comparatively short soft segment in the prepolymer. For the PUA prepolymers based on PEG having higher M-n values, chain-extending and grafting could impede the phase separation between the hard and the soft segment domains. The adhesion, impact strength and flexibility of the photocured films were tested.
文摘Cyclic acrylates, 2,2- dimethyl-5-methylene-1 , 3-dioxolan-4 -one and 2- phenyl-5-methylene-1,3-dioxolan-4-one, were synthesized successfully. The monomers were characterized by ~1H NMR, ^(13)C NMR, IR and elemental analysis or HRMS. Polymerization of the monomers were carried out at 120℃ with di-t-butylperoxide as initiator. The polymers were studied by ~1H NMR, ^(13)C NMR, UV and hydrolysis. The molecular weights of the resulting polymers were estimated by viscosity measurement and the extent of ring opening was estimated also by ~1H NMR and hydrolysis of the polymers and further confirmed by UV spectra.
基金This work was supported by the National Natural Science Foundation of China
文摘The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate (HOPA) and acrylic acid (AA) was used to prepare the acrylic latexes with high-solid content. The effects of monomer emulsion feed rates (R(a)) and (R/E)(E) values, the ratio of emulsifier amount between the initial charge (R) and the addition monomer emulsion (E), on the polymerization reaction features, the viscosities, surface tensions,particle sizes and particle sizes distributions of latexes, T-g and the insoluble fractions of films, the 180 degrees peel strength, tack and holding power of pressure-sensitive adhesive (PSA) tapes, prepared from the latexes, were studied. Experimental study shows that the grafting and crosslinking fraction in the PSA tapes must be controlled within a suitable range to keep the balance of the 180 degrees peel strength, tack and holding power.
基金supported by the Special Funds for Major State Basic Research Projects(No.2005CB623800) from the Ministry of Science and Technology of China
文摘A simple and effective way to prepare poly（acrylate）s, such as poly（methacrylate）, poly（butyl acrylate） and poly（butyl methacrylate）, has been achieved by using the single component aluminum-based compounds, such as modified methylaluminoxane （MMAO）, triisobutylaluminium （TIBA） and triethylaluminium （TEA） as initiators. Effective initiations and high molecular weight polymers with unimodal molecular weight distributions could be easily obtained by varying the reaction parameters of systems under mild conditions. Although these aluminum compounds were inefficient initiators for methyl methacrylate （MMA） polymerization, they exhibited remarkable catalytic activity for butyl methacrylate （BMA） polymerization, affording high molecular weight poly（BMA）s.
基金Project supported by the National Natural Science Foundation of China (Grant No. 29702006)the special fund of Nature Science of Tianjin
文摘Molecular modeling of acrylates (acrylamides) with D1 protein of Pisum sativum is presented. Studies show that the binding force mainly includes H-bond interaction, Van der Waals and π-ring stacking interaction. It was found that SER 268 in Dl protein might be an important binding site. It is important for high inhibitory activity of compounds whether an electronegative atom in alkyl of ester linkage could make H-bond interaction with SER 268 in Dl protein. Thus some new acrylates (acrylamides) were designed and synthesized, Bioassay indicated that these new compounds showed expected Hill reaction inhibitory activity.
文摘A direct three-component approach has been developed for the synthesis of a-cyano acrylates starting from al- dehydes, alcohols and a-cyano acetamide by employing cyanuric chloride as an organocatalyst. A class of structur- ally diverse a-cyano acrylates have been provided with good to excellent yields via the cascade transformation of Knoevenagel condensation and amide esterification.
基金Funded by the National Natural Science Foundation of China(No.52473077)China Three Gorges Corporation(No.202403190)。
文摘In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadequate post-cure toughness,which compromise fatigue resistance during service.To address these issues,we synthesized hydroxyl-terminated polyurethane acrylate prepolymers using diphenylmethane diisocyanate(MDI),polypropylene glycol(PPG),and hydroxyethyl methacrylate(HEMA).Fourier transform infrared spectroscopy(FTIR)confirmed successful prepolymer synthesis.We developed UV-curable resins by incorporating various crosslinking monomers and optimized the formulations through mechanical property analysis.Testing revealed that the polyurethane-acrylic UV-cured resin system combines polyurethane's mechanical excellence with acrylics'high UV-curing activity.The PPG200/MDI/HEMA formulation achieved superior performance,with a tensile strength of 55.31 MPa,an impact toughness of 22.7 kJ/m^(2),and a heat deflection temperature(HDT)of 132℃.The optimized system eliminates volatile components while maintaining high reactivity,addressing critical limitations in trenchless pipeline rehabilitation.The improved mechanical properties meet the operational demands of underground pipes,suggesting practical applicability in trenchless pipeline repair.
基金This work was financially supported by the National Natural Science Foundation of China，the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The one-pot sequential reaction of arylamines, methyl propiolate and 2-aryl-3-nitrochromenes without any catalyst in refluxing ethanol afforded the polysubstituted 3-（3-nitro-2-phenylchroman-4-yl）-3-arylaminoacrylates in good yields and with high diastereoselectivity. Reaction mechanism was believed involving the initial formation of β-enamino ester and sequential Michael addition.
基金This work was financially supported by the National Natural Science Foundation of China （Grant No. 21172189） and the Priority Academic Program Devel- opment of Jiangsu Higher Education Institutions.
文摘The functionalized arylidene bis（3-arylaminoacrylates） were efficiently prepared by FeCl3 catalyzed one-pot domino reactions of primary amines, methyl propiolate and aromatic aldehydes. When isatins were utilized under similar conditions, only 2-oxoindolinyl 3-arylaminoacrylates were obtained in moderate yields. ^1H NMR data and single crystal structures indicated that this reaction has high diastereoselectivity.
基金supported by the National Natural Science Foundation of China(Nos.42277315,22066009)the Scientific Research Startup Fund of Hainan University(Nos.XJ2300005916,kyqd(zr)22185)+1 种基金supported by Scientific Research Project of Hainan Higher Education Institutions(No.Hnky2023-9)Innovational Fund for Scientific and Technological Personnel of Hainan Province(No.KJRC2023C12)。
文摘Synergy strategy of photocatalysts and polymer resins are promising technology for marine antifouling.However,it is still a main challenge to obtain a green,safe,and efficient antifouling coatings.Herein,carbon(graphene or CNT)modified Ti O_(2)photocatalyst was synthesized via hydrothermal and annealing process and has successfully applied in acrylate fluoroboron polymer(ABFP)composite coating.Morphology and chemical composition were detailed characterized.The graphene or CNT acted as a bridge with supplemental spatial structures(petal gaps,entanglement)and new functional groups(C-O,C-Ti-O,etc.)on Ti O_(2)particle.Carbon nanotube(CNT)modified TiO_(2)-ABFP coatings(BTCP)achieved excellent antibacterial and anti-diatom adhesion rate of 89.3%-96.70%and 99.00%-99.50%,which was 1.84-4.94-fold more than that of the single ABFP.CNT or graphene served as electronic bridges was considered as the crucial mechanism,which significantly improved the light absorption range and capacity,conductivity,and photoelectric response of Ti O_(2),and further accelerated the generation and transfer of free radicals to the surface of BTCP or FTGP.Moreover,the improvement of catalyst activity synergizes with the smooth surface,hydrophilicity,and slow hydrolysis of composite coatings,achieved long-term and efficient antifouling performance.This work provides a new insight into the modification of Ti O_(2)and antifouling mechanism of polymer coating.
基金Project supported by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(SKLGP2020Z003)。
文摘A novel composite material,Poly(IL-AA)@MIL-101(Cr),combining metal-organic framework,polymeric ionic liquid and acrylic acid,was synthesized for the selective and efficient adsorption of rare earths europium(Ⅲ)(Eu3+).Characterization of the materials was carried out using techniques such as X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS),thermogravimetric analysis(TGA)and Brunauer-Emmett-Teller(BET).The results demonstrate successful incorporation of the polymeric ionic liquid onto the material surface while preserving the crystal structure and mo rphology of MIL-101(Cr).Adsorption experiments were conducted to explore parameters including equilibrium pH,initial Eu3+concentration,and duration,with comprehensive analyses of adsorption kinetics,isotherms,and mechanisms.Findings reveal that Poly(IL1-AA)@MIL-101(Cr),Poly(IL3-AA)@MIL-101(Cr),and Poly(IL5-AA)@MIL-101(Cr)achieve adsorption equilibrium for Eu3+at approximately 9 h with an equilibrium pH of 6.2.The adso rption of Eu^(3+)predominantly follows a pseudo-second-order kinetic model and Langmuir isotherm adsorption model.Moreover,the prepared composite material exhibits superior adsorption selectivity for Eu^(3+)over other metal ions in the mixture(K^(+),Mg^(2+),Ni^(2+),Co^(2+),Zn^(2+),La^(3+),and Nd^(3+)).Even after five adsorption-desorption cycles,the composite material maintains satis factory adsorption performance.
基金Funded by the National Natural Science Foundation of China(No.51873167)the Self-determined and Innovative Research Funds of WUT(No.2024-CL-B1-02)。
文摘Modified activated carbons(AS)were fabricated through the oxidation effect of ammonium persulfate and applied to the dynamic adsorption of different acrylate gas.The pore structures,surface chemical properties and surface morphology of AS were respectively characterized by N2 adsorption,Boehm titration,X-ray Photoelectron Spectroscopy(XPS)and scanning electron microscopy(SEM)techniques.After modification,the specific surface area increased from 954 to 1154 m^(2)·g^(-1).The contents of oxygen-containing functional groups on the AS surface increase obviously and have a great effect on the adsorption behavior of acrylate gases.According to the results of dynamic adsorption,the adsorption capacities of acrylates are as the following order:methyl acrylate(461.9 mg·g^(-1))>methyl methacrylate(436.9 mg·g^(-1))>butyl acrylate(381.8 mg·g^(-1)),which is attributed to the size adaptability of AS pores and acrylates.The adsorption behavior of AS for acrylate gases conforms to the Bangham model and the Temkin model.
基金supported by the National Natural Science Foundation of China(No,22271074)Natural Science Foundation of Hebei Province(Nos.B2023208042,B2022208032,B2021208066,E2024208084 , E2024208088)+2 种基金Science Research Project of Hebei Education Department(No.JZX2024013)Special Fund for Local Scientific and Technological Development under the Guidance of the Central Government(No.236Z3704G)Hebei Province High Level Talent Funding(No.A202001010).
文摘Flexible wearable electronic devices based on hydrogels have immense potential in a wide range of applications.However,many existing strain sensors suffer from significant limitations including poor mechanical properties,low adhesion,and insufficient conductivity.To address these challenges,this study successfully developed an organic-inorganic double-network conductive hydrogel using acrylic-modified bentonite (AABT) as a key component.The incorporation of AABT significantly enhanced the mechanical properties of the ATHG@LiCl hydrogel,achieving an impressive stretchability of 4000% and tensile strength of 250 kPa.Moreover,it improved the electrical conductivity of the hydrogel to a maximum of 1.53 mS/cm.The catechol structure of tannic acid (TA) further augmented the adhesive properties of the ATHG@LiCl hydrogel toward various substrates such as copper,iron,glass,plastic,wood,and pigskin.The addition of lithium chloride (LiCl) and dimethyl sulfoxide(DMSO) endowed the hydrogel with exceptional freezing resistance and flexibility,even at low temperatures of-20℃.Remarkably,the hydrogel maintained a conductivity of 0.53 mS/cm under these conditions,surpassing the performance of many other reported hydrogels.Furthermore,the ATHG@LiCl hydrogel demonstrated outstanding characteristics,such as high sensitivity (gauge factor GF=4.50),excellent transparency (90%),and reliable strain-sensing capabilities,indicating that the ATHG@LiCl hydrogel is a highly promising candidate for flexible wearable soft materials,offering significant advancements in both functionality and performance.
文摘Vanadium phosphorus oxide(VPO)catalyst is a promising candidate for the condensation reaction of formaldehyde(FA)and acetic acid(HAc)to produce acrylic acid(AA).However,the complexity of the active phases and their dynamic interconversion under redox conditions has led to controversies regarding the actual active phase in this reaction.To address this,this study systematically investigates the phase transition and underlying mechanism of VPO catalysts under reaction conditions.X-ray diffraction(XRD)patterns,Raman spectra,transmission electron microscopy images and X-ray photoelectron spectroscopy collectively demonstrated that the V^(4+)phase(VO)_(2)P_(2)O_(7)retained the bulk phase structure throughout the reaction,with only minor surface phase transition observed.In contrast,the V^(5+)phase underwent reduction to other phases in both bulk and surface regions.Specifically,theδ-VOPO_(4)phase rapidly transformed into theαII-VOPO_(4)phase,which could reversibly convert into the R1-VOHPO_(4)phase(V^(4+)).Controlled variable experiments,H_(2)-temperature programmed reduction and in-situ XRD experiments in a hydrogen atmosphere further demonstrated that these phase transitions were primarily attributed to the loss of lattice oxygen.The presence of V^(4+)phase in VPO catalysts enhanced the selectivity of acrylic acid,while the existence of V^(5+)phase promoted the activation of acetic acid.This work elucidates the redox-driven phase evolution of VPO catalysts and offers valuable insights for designing efficient catalysts for FA-HAc cross-condensation by balancing phase stability and activity.
