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
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
Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumesc...Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumescent flame retardant(IFR)system containing silicone-containing macromolecular charring agent(Si-MCA)and ammonium polyphosphate(APP)was designed to synergistically improve the flame retardancy and mechanical properties of ethylene-butyl acrylate copolymer(EBA)composites.The optimal mass ratio of APP/Si-MCA was 3/1 in EBA composites(EBA/APP-Si-31),corresponding to the best flame retardancy with 31.2% of limited oxygen index(LOI),V-0 rating in UL-94 vertical burning test,and 76.4%reduction on the peak of heat release rate(PHRR)in cone calorimeter test.The enhancement mechanism was attributed to the synergistic effect of APP/Si-MCA during combustion,including the radical-trapping effect,the dilution effect of non-flammable gases,and the barrier effect of the intumescent char layer.Meanwhile,the tensile results indicated that EBA/APP-Si-31 also exhibited good mechanical properties with the addition of maleic anhydride-grafted polyethylene(PE-g-MA)as the compatibilizer.Thus,the APP/Si-MCA combination is an effective IFRs system for preparing high-performance EBA composites,and it will promote their applications as cable sheath materials.展开更多
Smart pesticide delivery systems based on stimuli-responsive nanocarriers have attracted considerable attention because of their potential to enhance pesticide efficiency while reducing environmental risks.In this stu...Smart pesticide delivery systems based on stimuli-responsive nanocarriers have attracted considerable attention because of their potential to enhance pesticide efficiency while reducing environmental risks.In this study,a novel p H/glutathione dual-responsive pesticide delivery system was constructed through the synthesis of disulfide-bridged hollow mesoporous organosilica nanospheres(HMONs)via the St??ber method,followed by poly(acrylic acid)(PAA)coating through distillation-precipitation polymerization to form HMONs@PAA nanocomposites.The resulting abamectin-loaded system(Abamectin-HMONs@PAA)demonstrated a 12.73% pesticide loading capacity and significantly improved photostability,retaining twice as much active ingredient as free abamectin after 250 h of UV irradiation(36 W).Release studies revealed p H-and glutathione-dependent characteristics,with cumulative releases in acidic conditions exceeding those in neutral and alkaline environments by 18.66% and 40.98%,respectively,and a 14.2% increase in glutathione-containing solution(0.2 mmol·L^(-1) in 70% ethanol)after 97 h.Bioassays showed superior performance against Plutella xylostella,with a 13.33% reduction in survival rate compared to conventional suspension at equivalent dosage(40 mg·L^(-1)),while maintaining efficacy after extensive rainfall simulation(20 events over 10 days).This study provides a promising approach for developing environmentally responsive nanopesticides with enhanced durability and controlled-release properties,offering significant potential for sustainable crop protection.展开更多
By means of initiation of the high temperature and shearing stress of an extruder,we synthesized the graft copolymer of starch with acrylate monomers based on the simple dry method.The eff...By means of initiation of the high temperature and shearing stress of an extruder,we synthesized the graft copolymer of starch with acrylate monomers based on the simple dry method.The effects of reaction conditions on graft copolymerization were discussed. Grafted starch used as a compatibilizer for the blend system of starch and polyethylene was further investigated. The results indicate that grafted starch as a compatibilizer can improve the mechanical properties and rheologic properties of the blend of starch and polyethylene.展开更多
Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolyme...Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolymerization. The variables affecting the degree of grafting, such as the time of UV (Ultraviolet-visible) irradiation and the concentrations of the methyl acrylate and photoinitiator, were investigated. The graft copolymer membranes were prepared by the phase inversion method. The chemical and morphological changes were characterized by attenuated total reflection-Fourier transform infrared spectroscopy (ATR/FT-IR), scanning electron microscopy, and water contact angles measurements. Results revealed that methyl acrylate groups were present on the membranes and the graft degree of methyl acrylate had remarkable effect on the performance of membranes. Pure water contact angle on the membrane surface decreases with the increase of methyl acrylate graft degree, which indicated that the hydrophilicity of graft copolymer membranes was improved. The permeation fluxes of pure water and bovine serum albumin solution were measured to evaluate the antifouling property of graft copolymer membranes, the results of which have shown an enhancement of antifouling property for graft copolymer membranes.展开更多
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 dynamic mechanical properties of a new blend system consisting of phenol resin and polar polymer (acrylaterubber and/or chlorinated polypropylene) were investigated. It was found that the addition of phenol resin ...The dynamic mechanical properties of a new blend system consisting of phenol resin and polar polymer (acrylaterubber and/or chlorinated polypropylene) were investigated. It was found that the addition of phenol resin to acrylate rubberand its incompatible blend can cause a remarkable improvement in the temperature dependence of the loss tangent. As a result, the present blends are very good damping materials.展开更多
Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering ...Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%.展开更多
A novel ohthalazinone modified epoxy acrylate resin for the high temperature resistant ultravioet (UV) curable coating.was syn-thesized.The methacrylated epoxy resins obtained were utilized to UV radiation curing by...A novel ohthalazinone modified epoxy acrylate resin for the high temperature resistant ultravioet (UV) curable coating.was syn-thesized.The methacrylated epoxy resins obtained were utilized to UV radiation curing by taking 2.5% (wt%) of photoinitiator in combination with 20% (wt%) of diluent, and generated the interpenetraring polymer networks. The cured film had good thermal and chemical stability.展开更多
A novel UV-curable prepolymer polypropyleneglycol diglycidyl ether diacrylate (PPGGEA) was synthesized by utilizing polypropyleneglycol diglycidyl ether (PPGGE) and acrylic acid (AA) as starting materials, N, N-...A novel UV-curable prepolymer polypropyleneglycol diglycidyl ether diacrylate (PPGGEA) was synthesized by utilizing polypropyleneglycol diglycidyl ether (PPGGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were in the following: the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ~C, and the molar ratio of PPGGE to AA was 1:2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-cured initiator was added to the synthesized PPGGEA to prepare a kind of UV-cured coating. The mechanical properties of the UV-cured films were determined, giving 29.99 MPa of tensile strength, 834.27 MPa of the Young's modulus and 5.66% of elongation at tear.展开更多
The development of polymeric optical materials with a higher refractive index,transparency in the visible spectrum region and easier processability is increasingly desirable for advanced optical applications such as m...The development of polymeric optical materials with a higher refractive index,transparency in the visible spectrum region and easier processability is increasingly desirable for advanced optical applications such as microlenses,image sensors,and organic light-emitting diodes.Most acrylates have a low refractive index(around 1.50)which does not meet the high perfo rmance requirements of advanced optical materials.In this research,three novel acrylates were synthesized via a facile one-step approach and used to fabricate optical transparent polymers.All of the polymers reveal good optical properties including high transparency(≥90%)in the visible spectrum region and high refractive index values(1.6363)at 550 nm.Moreover,nanostructures of these acrylate polymers with various feature sizes including nanogratings and photonic crystals were successfully fabricated using nanoimprint lithography.These results indicate that these acrylates can be used in a wide range of optical and optoelectronic devices where nanopatterned films with high refractive index and transparency are required.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
The PAL was synthesized with BA,MMA and some monomers containing carboxyl groups(for example,acrylic acid(AA) and methacrylic acid(MAA)) as co-monomers by semi-continuous seeded emulsion polymerization technique...The PAL was synthesized with BA,MMA and some monomers containing carboxyl groups(for example,acrylic acid(AA) and methacrylic acid(MAA)) as co-monomers by semi-continuous seeded emulsion polymerization technique.The influences of alkalinization temperature,the feeding manner of AA or MAA on the particles size,rheological properties and carboxyl distribution of the latex were discussed,and the rheological mechanism was analyzed.The experimental results show that the PAL system has preferable viscosity and particle size when the alkalinization temperature is 50 ℃.Different distribution of carboxyl group in the particles and different resultant rheological properties are obtained by different feeding manner of AA or MAA into the system.The TEM images show that the particle is a smooth globe with carboxyl group concentrating on the surface and stabilized with electric double layer and nonionic adsorbed layer.The concentration of carboxyl functional group on the surface of particles can be achieved by the specific polymerization technique.The rheologyical properties are determined by accretion of particle volume and variation of the two phase volume ratio resulted from the carboxyl group spreading layer.展开更多
Photoinitiated inverse emulsion polymerization of sodium acrylate(AANa)in kerosene was carried out at room orlower temperature,using 2,2-dimethoxy-2-phenylacetophenone(DMPA)as the initiator.Kinetic investigations indi...Photoinitiated inverse emulsion polymerization of sodium acrylate(AANa)in kerosene was carried out at room orlower temperature,using 2,2-dimethoxy-2-phenylacetophenone(DMPA)as the initiator.Kinetic investigations indicated thatthe polymerization could be completed in about 30 min and produce polymer with high molecular weight(10~6~10~7).It wasfound that monomer droplets are the main sites for the polymerization(nucleation).With the increase of DMPAconcentration,polymerization rate(R_p)reaches a maximum value while molecular weight of the produced polymer has anadverse result,but the dependence of R_p on incident light intensity is similar.Influences of other parameters such asmonomer concentration,emulsifier content and reaction temperature,etc.were also studied.At lower pH values of waterphase,R_p depends strongly on the pH due to the electrostatic interaction between the ionized radicals and the monomer.Athigher pH,R_p shows a slight dependence on pH.展开更多
Polyacrylonitrile-block-poly(methyl acrylate)(P(AN-b-MA)) was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization employing macro-RAFT agent (PAN-RAFT) as the chain transfer...Polyacrylonitrile-block-poly(methyl acrylate)(P(AN-b-MA)) was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization employing macro-RAFT agent (PAN-RAFT) as the chain transfer agent and azobis(isobutyronitrile) (AIBN) as the initiator. A linear relationship between ln([M]0/[M]1) and reaction time was observed. The molecular structure of P(AN-b-MA) was characterized by ^1H-NMR, element analysis, FTIR and SEC. The molecular weight distribution (MWD) was less than 1.40, the Mn could be controled from 0.733 to 4.834×10^4, and the molar content of MA in P(AN-b-MA) were from 15.6 to 75.0 percentage, respectively.展开更多
Thermo-responsive butyl acrylate/furfuryl methacrylate copolymer-based (PBF backbone) graft (co)polymers with dynamic covalent linkages between their backbones and side chains via the Diels-Alder reaction of furar...Thermo-responsive butyl acrylate/furfuryl methacrylate copolymer-based (PBF backbone) graft (co)polymers with dynamic covalent linkages between their backbones and side chains via the Diels-Alder reaction of furardmaleimide were synthesized. Atom transfer radical polymerization (ATRP) was used to synthesize graft copolymers with thermo-responsive transformation from graft copolymers to linear polymers with bimodal or wide MWD. The NMR measurements indicated that the Diels-Alder reaction and retro- Diels-Alder reaction occurred, depending on the change of the temperature, meaning that the side chains could be cleaved and reformed according to the variation of the temperature. GPC measurements demonstrated that the molecular weights of the polymers were thermo- responsive. Furthermore, three graft copolymers with various branching chains (PBF-g-PBA, PBF-g-P(BMA-co-MA) and PBF-g-PBMA) were compared to study the influence of compatibility between the backbone and the branching chain on the efficiency of Diels-Alder reaction after the cleavage of the DA linkage. The results showed that the ability of the side chains to come back to the main chain was strongly affected by the compatibility between the backbone and the side chains and the flexibility of the polymer chains.展开更多
UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB_2-type monomers have been prepared by the authors. A series of work on allyl ether maleate hyperbranched polyester...UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB_2-type monomers have been prepared by the authors. A series of work on allyl ether maleate hyperbranched polyesters for UV curing coatings by Hult and his colleagues has been reported. However, the UV cured films from those materials are all flammable when attached to fire without addition of flame retardants.展开更多
A novel UV-curable prepolymer hexanediol diglycidyl ether diacrylate (HDGEA) was synthesized by utilizing hexanediol diglycidyl ether (HDGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine ...A novel UV-curable prepolymer hexanediol diglycidyl ether diacrylate (HDGEA) was synthesized by utilizing hexanediol diglycidyl ether (HDGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimal synthetic conditions were that the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ℃, and the molar ratio of HDGE to AA was 1︰2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-curing initiator was added to the synthesized HDGEA to prepare a kind of UV-curing coating. The mechanical properties of the UV-cured films were determined, giving 31.87 MPa of tensile strength, 871.88 MPa of Young's modulus and 6.77% of elongation at tear.展开更多
UV-curable hyperbranched polyurethane acrylate-polyurethane diacrylate/SiO2 dispersion (HBPUA-PUDA/SiO2) was prepared with isophorone diisocyanate (IPDI), hyperbranched polyester Boltorn H20 (H20), hydroxy-ethyl...UV-curable hyperbranched polyurethane acrylate-polyurethane diacrylate/SiO2 dispersion (HBPUA-PUDA/SiO2) was prepared with isophorone diisocyanate (IPDI), hyperbranched polyester Boltorn H20 (H20), hydroxy-ethyl acrylate (HEA), polyethyleneglycol (PEG-200)and nano-SiO2. The UV curing kinetics of the films was investigated by FTIR. The results show that the curing speed of the films increases with the adding of nano-SiO2 and decreases with the adding of PUDA due to the slower chain movement. The thermal stability of the HBPUA-PUDA/SiO2 films was studied by using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TGA/FTIR). The results show that all films exhibit two degradation stages located at about 320 and 440℃ corresponding to the degradation for hard segments of urethane-acrylate and the degradation for soft segment and polyester core. In addition, the results from the analysis of TGA/FTIR also indicate that the decomposition temperature of HBPUA-PUDA/SiO2 film is 15℃ higher than that obtained for pure polymer. The degradation mechanism was proposed according to TGA/FTIR results.展开更多
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(52473059)Taishan Scholar Constructive Engineering Foundation of Shandong Province(tsqn202103079)Key Research and Development Plan of Shandong Province(2024TSGC0264).
文摘Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumescent flame retardant(IFR)system containing silicone-containing macromolecular charring agent(Si-MCA)and ammonium polyphosphate(APP)was designed to synergistically improve the flame retardancy and mechanical properties of ethylene-butyl acrylate copolymer(EBA)composites.The optimal mass ratio of APP/Si-MCA was 3/1 in EBA composites(EBA/APP-Si-31),corresponding to the best flame retardancy with 31.2% of limited oxygen index(LOI),V-0 rating in UL-94 vertical burning test,and 76.4%reduction on the peak of heat release rate(PHRR)in cone calorimeter test.The enhancement mechanism was attributed to the synergistic effect of APP/Si-MCA during combustion,including the radical-trapping effect,the dilution effect of non-flammable gases,and the barrier effect of the intumescent char layer.Meanwhile,the tensile results indicated that EBA/APP-Si-31 also exhibited good mechanical properties with the addition of maleic anhydride-grafted polyethylene(PE-g-MA)as the compatibilizer.Thus,the APP/Si-MCA combination is an effective IFRs system for preparing high-performance EBA composites,and it will promote their applications as cable sheath materials.
基金financially supported by the Jiangsu Forestry Science and Technology Innovation and Promotion Project(No.LYKJ-Nanjing[2022]02)the Jiangsu Agricultural Science and Technology Innovation Fund(No.CX(23)3090)。
文摘Smart pesticide delivery systems based on stimuli-responsive nanocarriers have attracted considerable attention because of their potential to enhance pesticide efficiency while reducing environmental risks.In this study,a novel p H/glutathione dual-responsive pesticide delivery system was constructed through the synthesis of disulfide-bridged hollow mesoporous organosilica nanospheres(HMONs)via the St??ber method,followed by poly(acrylic acid)(PAA)coating through distillation-precipitation polymerization to form HMONs@PAA nanocomposites.The resulting abamectin-loaded system(Abamectin-HMONs@PAA)demonstrated a 12.73% pesticide loading capacity and significantly improved photostability,retaining twice as much active ingredient as free abamectin after 250 h of UV irradiation(36 W).Release studies revealed p H-and glutathione-dependent characteristics,with cumulative releases in acidic conditions exceeding those in neutral and alkaline environments by 18.66% and 40.98%,respectively,and a 14.2% increase in glutathione-containing solution(0.2 mmol·L^(-1) in 70% ethanol)after 97 h.Bioassays showed superior performance against Plutella xylostella,with a 13.33% reduction in survival rate compared to conventional suspension at equivalent dosage(40 mg·L^(-1)),while maintaining efficacy after extensive rainfall simulation(20 events over 10 days).This study provides a promising approach for developing environmentally responsive nanopesticides with enhanced durability and controlled-release properties,offering significant potential for sustainable crop protection.
文摘By means of initiation of the high temperature and shearing stress of an extruder,we synthesized the graft copolymer of starch with acrylate monomers based on the simple dry method.The effects of reaction conditions on graft copolymerization were discussed. Grafted starch used as a compatibilizer for the blend system of starch and polyethylene was further investigated. The results indicate that grafted starch as a compatibilizer can improve the mechanical properties and rheologic properties of the blend of starch and polyethylene.
文摘Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolymerization. The variables affecting the degree of grafting, such as the time of UV (Ultraviolet-visible) irradiation and the concentrations of the methyl acrylate and photoinitiator, were investigated. The graft copolymer membranes were prepared by the phase inversion method. The chemical and morphological changes were characterized by attenuated total reflection-Fourier transform infrared spectroscopy (ATR/FT-IR), scanning electron microscopy, and water contact angles measurements. Results revealed that methyl acrylate groups were present on the membranes and the graft degree of methyl acrylate had remarkable effect on the performance of membranes. Pure water contact angle on the membrane surface decreases with the increase of methyl acrylate graft degree, which indicated that the hydrophilicity of graft copolymer membranes was improved. The permeation fluxes of pure water and bovine serum albumin solution were measured to evaluate the antifouling property of graft copolymer membranes, the results of which have shown an enhancement of antifouling property for graft copolymer membranes.
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This work was supported by the "The National High Technology Research and Development Program" of Ministry of Science and Technology of China (No. 2002AA333020).
文摘The dynamic mechanical properties of a new blend system consisting of phenol resin and polar polymer (acrylaterubber and/or chlorinated polypropylene) were investigated. It was found that the addition of phenol resin to acrylate rubberand its incompatible blend can cause a remarkable improvement in the temperature dependence of the loss tangent. As a result, the present blends are very good damping materials.
基金supported by the Science and Technology Department of Zhejiang Province under Grant No. 2010C31040the financial support of Zhejiang Provincial Natural Science Foundation of China(No. Y4100152)Zhejiang University of Technology Natural Science Foundation(No.20100202)
文摘Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%.
文摘A novel ohthalazinone modified epoxy acrylate resin for the high temperature resistant ultravioet (UV) curable coating.was syn-thesized.The methacrylated epoxy resins obtained were utilized to UV radiation curing by taking 2.5% (wt%) of photoinitiator in combination with 20% (wt%) of diluent, and generated the interpenetraring polymer networks. The cured film had good thermal and chemical stability.
基金the Innovatory Group Program of the Natural Science Foundation of Hubei Province(No.2004ABC001)the National"863"Hi-tech Foundation of China(No.2002AA6Z3083)
文摘A novel UV-curable prepolymer polypropyleneglycol diglycidyl ether diacrylate (PPGGEA) was synthesized by utilizing polypropyleneglycol diglycidyl ether (PPGGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were in the following: the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ~C, and the molar ratio of PPGGE to AA was 1:2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-cured initiator was added to the synthesized PPGGEA to prepare a kind of UV-cured coating. The mechanical properties of the UV-cured films were determined, giving 29.99 MPa of tensile strength, 834.27 MPa of the Young's modulus and 5.66% of elongation at tear.
基金supported by the Molecular Foundry,Lawrence Berkeley National Laboratory,which is supported by the Office of Science and Office of Basic Energy Sciences of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231supported by National Natural Science Foundation of China (No.51573011)+2 种基金Natural Foundation of Jiangsu Province (No. BK20150272)Beijing Laboratory of Biomedical Materialsthe scholarship support from the program of the China Scholarship Council (No.201706880022) for study at Lawrence Berkeley National Laboratory
文摘The development of polymeric optical materials with a higher refractive index,transparency in the visible spectrum region and easier processability is increasingly desirable for advanced optical applications such as microlenses,image sensors,and organic light-emitting diodes.Most acrylates have a low refractive index(around 1.50)which does not meet the high perfo rmance requirements of advanced optical materials.In this research,three novel acrylates were synthesized via a facile one-step approach and used to fabricate optical transparent polymers.All of the polymers reveal good optical properties including high transparency(≥90%)in the visible spectrum region and high refractive index values(1.6363)at 550 nm.Moreover,nanostructures of these acrylate polymers with various feature sizes including nanogratings and photonic crystals were successfully fabricated using nanoimprint lithography.These results indicate that these acrylates can be used in a wide range of optical and optoelectronic devices where nanopatterned films with high refractive index and transparency are required.
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Funded by the National Natural Science Foundation of China (No.50803017)
文摘The PAL was synthesized with BA,MMA and some monomers containing carboxyl groups(for example,acrylic acid(AA) and methacrylic acid(MAA)) as co-monomers by semi-continuous seeded emulsion polymerization technique.The influences of alkalinization temperature,the feeding manner of AA or MAA on the particles size,rheological properties and carboxyl distribution of the latex were discussed,and the rheological mechanism was analyzed.The experimental results show that the PAL system has preferable viscosity and particle size when the alkalinization temperature is 50 ℃.Different distribution of carboxyl group in the particles and different resultant rheological properties are obtained by different feeding manner of AA or MAA into the system.The TEM images show that the particle is a smooth globe with carboxyl group concentrating on the surface and stabilized with electric double layer and nonionic adsorbed layer.The concentration of carboxyl functional group on the surface of particles can be achieved by the specific polymerization technique.The rheologyical properties are determined by accretion of particle volume and variation of the two phase volume ratio resulted from the carboxyl group spreading layer.
基金This work was supported by the Scientific Research Foundation for Youth(No.QN0404).
文摘Photoinitiated inverse emulsion polymerization of sodium acrylate(AANa)in kerosene was carried out at room orlower temperature,using 2,2-dimethoxy-2-phenylacetophenone(DMPA)as the initiator.Kinetic investigations indicated thatthe polymerization could be completed in about 30 min and produce polymer with high molecular weight(10~6~10~7).It wasfound that monomer droplets are the main sites for the polymerization(nucleation).With the increase of DMPAconcentration,polymerization rate(R_p)reaches a maximum value while molecular weight of the produced polymer has anadverse result,but the dependence of R_p on incident light intensity is similar.Influences of other parameters such asmonomer concentration,emulsifier content and reaction temperature,etc.were also studied.At lower pH values of waterphase,R_p depends strongly on the pH due to the electrostatic interaction between the ionized radicals and the monomer.Athigher pH,R_p shows a slight dependence on pH.
文摘Polyacrylonitrile-block-poly(methyl acrylate)(P(AN-b-MA)) was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization employing macro-RAFT agent (PAN-RAFT) as the chain transfer agent and azobis(isobutyronitrile) (AIBN) as the initiator. A linear relationship between ln([M]0/[M]1) and reaction time was observed. The molecular structure of P(AN-b-MA) was characterized by ^1H-NMR, element analysis, FTIR and SEC. The molecular weight distribution (MWD) was less than 1.40, the Mn could be controled from 0.733 to 4.834×10^4, and the molar content of MA in P(AN-b-MA) were from 15.6 to 75.0 percentage, respectively.
基金financially supported by the National Natural Science Foundation of China(Nos.51233005,21374114,and21274152)
文摘Thermo-responsive butyl acrylate/furfuryl methacrylate copolymer-based (PBF backbone) graft (co)polymers with dynamic covalent linkages between their backbones and side chains via the Diels-Alder reaction of furardmaleimide were synthesized. Atom transfer radical polymerization (ATRP) was used to synthesize graft copolymers with thermo-responsive transformation from graft copolymers to linear polymers with bimodal or wide MWD. The NMR measurements indicated that the Diels-Alder reaction and retro- Diels-Alder reaction occurred, depending on the change of the temperature, meaning that the side chains could be cleaved and reformed according to the variation of the temperature. GPC measurements demonstrated that the molecular weights of the polymers were thermo- responsive. Furthermore, three graft copolymers with various branching chains (PBF-g-PBA, PBF-g-P(BMA-co-MA) and PBF-g-PBMA) were compared to study the influence of compatibility between the backbone and the branching chain on the efficiency of Diels-Alder reaction after the cleavage of the DA linkage. The results showed that the ability of the side chains to come back to the main chain was strongly affected by the compatibility between the backbone and the side chains and the flexibility of the polymer chains.
基金Supported by the National Natural Science Foundation of China(No. 20074034).
文摘UV curable hyperbranched prepolymers based on amine-ester, ester-amide and ether-amide started with AB_2-type monomers have been prepared by the authors. A series of work on allyl ether maleate hyperbranched polyesters for UV curing coatings by Hult and his colleagues has been reported. However, the UV cured films from those materials are all flammable when attached to fire without addition of flame retardants.
基金Funded by the Natural Science Foundation of Jiangxi Province (No.2008GZC0021)the National "863" Hi-tech Foundation of China (No.2002AA6Z3083)
文摘A novel UV-curable prepolymer hexanediol diglycidyl ether diacrylate (HDGEA) was synthesized by utilizing hexanediol diglycidyl ether (HDGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimal synthetic conditions were that the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90-110 ℃, and the molar ratio of HDGE to AA was 1︰2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-curing initiator was added to the synthesized HDGEA to prepare a kind of UV-curing coating. The mechanical properties of the UV-cured films were determined, giving 31.87 MPa of tensile strength, 871.88 MPa of Young's modulus and 6.77% of elongation at tear.
文摘UV-curable hyperbranched polyurethane acrylate-polyurethane diacrylate/SiO2 dispersion (HBPUA-PUDA/SiO2) was prepared with isophorone diisocyanate (IPDI), hyperbranched polyester Boltorn H20 (H20), hydroxy-ethyl acrylate (HEA), polyethyleneglycol (PEG-200)and nano-SiO2. The UV curing kinetics of the films was investigated by FTIR. The results show that the curing speed of the films increases with the adding of nano-SiO2 and decreases with the adding of PUDA due to the slower chain movement. The thermal stability of the HBPUA-PUDA/SiO2 films was studied by using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TGA/FTIR). The results show that all films exhibit two degradation stages located at about 320 and 440℃ corresponding to the degradation for hard segments of urethane-acrylate and the degradation for soft segment and polyester core. In addition, the results from the analysis of TGA/FTIR also indicate that the decomposition temperature of HBPUA-PUDA/SiO2 film is 15℃ higher than that obtained for pure polymer. The degradation mechanism was proposed according to TGA/FTIR results.