最新刊期
卷 ， 期 2 ， 2016
- 摘要：This paper reports a polythiophene derivative that contains oligo(ethylene oxide) short side chains,poly(3-oligo(ethylene oxide)3-thiophene) (P3OET) of Mn 6000,which is synthesized by nickel-catalyzed polymerization of 2-bromo-5-iodine-3-oligo(ethylene oxide)3-thiophene.The presented P3OET can well dissolve in tetrahydrofuran,a good solvent,and emit orange-colored light under UV illumination at room temperature.In water,a selective polar solvent of P3OET,P3OET self-assembled into spherical nanostructures that showed a red-colored emission with a red-shifted spectrum and decreased quantum yield,in comparison with that in tetrahydrofuran; in contrast,in methanol,another selective polar solvent of P3OET,P3OET self-assembled into silk-like nanostructures that showed a yellow-colored emission with a blue-shifted spectrum and enhanced quantum yield,which is a quite unusual phenomenon that is also called aggregation-enhanced emission.Moreover,the integration of oligo(ethylene oxide) and polythiophenes made the presented P3OET exhibit temperature responsive behavior in aqueous solutions,similar to that of the temperature responsive polymers of oligo(ethylene glycol) methacrylate reported previously in literatures.This unique property of oligo(ethylene oxide)-contained polymers resulted in reversible temperature-induced twisting of the polythiophene conjugated backbone,allowing the reversible varying on the conjugation length by changing the temperature in milieu,which was accompanied by pronounced spectroscopic changes.At elevated temperatures,the blue-shifted spectra with enhanced intensities were recorded in aqueous solutions.These unique features of P3OET make it possess great potential for chemo-/bio-detection applications.With mouse melanoma B16F10 cells as the model,the experimental results indicate that the P3OET assemblies can enter the cells and readily emit strong visible fluorescence for cellular imaging.The temperature responsive behavior of P3OET also allow manipulate the fluorescence intensity for sensing the cellular temperature change.The cellular temperature change can be induced by both the heat generated by an external heater and the intracellular temperature variations induced by external chemical stimuli,e.g.,adding carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone,an uncoupler of oxidative phosphorylation in mitochondria that can cause heat production by respiration,or adding 5-fluorouracil,an anticancer drug that can also induce an unveiled temperature variation due to early responses of apoptosis such as DNA cleavage.关键词：Polythiophenes;Oligo(ethylene oxide);Aggregation-enhanced emission;Temperature responsive;Cellular imaging
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发布时间：2021-03-19
Rapid Communications
- 摘要：Compared with traditional hydrogels,self-healing hydrogels can restore their structures and functionalities automatically after damage,which have caused extensive concern as smart soft materials in recent years.The rapid development of multi-responsive dynamic self-healing hydrogels has been achieved by introducing the concept of constitutional dynamic chemistry in this field.In this review,the current strategies for synthesizing self-healing hydrogels based on the concept of constitutional dynamic chemistry are introduced,including multiple hydrogen bonds,hydrophobic interactions,imine bonds,acylhydrazone bonds,etc.Furthermore,the key factors affecting self-healing properties and the applications of self-healing hydrogels in biomedicine are discussed,as well as the challenge and future development of self-healing hydrogels are proposed.关键词：Self-healing;Hydrogels;Constitutional dynamic chemistry
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发布时间：2021-03-19
Reviews
- 摘要：Novel coral-like polyaniline (PANI) sub-micrometer particles were successfully synthesized by adding the aniline monomer aqueous solution into the ammonium persulfate aqueous solution,which is different from the traditional method.It can be observed by scanning electron microscopy (SEM) that the surface morphology of the obtained PANI particles was very rough and there were a large amount of nanometer-sized embossment.Three types of polyvinyl alcohol (PVA),namely 1799,1788 and CP-1000,were respectively used as stabilizer.The obtained PANI particles are named as PANI-1,PANI-2 and PANI-3 with average diameter of 250 nm,215 nm and 140 nm.The size distribution also became narrow as the size decreased.Therefore,the solubility of the stabilizer in water and its molecular weight had profound influence on the aggregation and size of PANI particles.The chemical structures,thermostability,crystal structure,electrical property and surface area of the obtained PANI particles were further characterized by Fourier transform infrared spectroscopy (FTIR),thermogravimetric analysis (TGA),powder X-ray diffraction (XRD),four-probe conductivity meter and N2 adsorption-desorption isotherms.The conductivity of PANI particles can attain 2.7 S cm-1.The formation mechanism of the coral-like surface morphology was also discussed.关键词：Polyaniline;Coral-like surface morphology;Sub-micrometer particles;Conductivity
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发布时间：2021-03-19 - 摘要：A series of spinnable polyaluminocarbosilane (PACS) with different Al contents were prepared from different ratios of low-molecular polycarbosilane (L-PCS) and aluminum acetylacetonate [Al(AcAc)3].The mass distribution and the structure of PACS were investigated.In addition,the oxidation curing behavior of the PACS fibers was studied,in contrast to that of the PCS fibers.The results show that [Al(AcAc)3] was introduced to L-PCS by the formation of the Al(AcAc)2 hanging and the Al(AcAc) bridging.The PACS has a bimodal mass distribution,which leads to good spinnability.Both the number and reactivity of SiH in PACS decreased with the increase of the Al content.Moreover,the SiOH was prevented from forming the SiOSi crosslinking bonds,which were produced by the oxidation of SiH.As the increase of Al content,the gel-point temperature was retarded to high temperatures and the gel content increased slowly with the elevation of temperature.Consequently,excessive oxygen was introduced into the cured fibers.By means of preoxidation and self-crosslinking,the oxygen content of cured PACS fibers was reduced under 11 wt%.The self-crosslinking mechanism includes the following two ways.Firstly,the activated SiOH reacts with each other to form SiOSi by releasing H2O.Secondly,SiH reacts with SiOH or SiCH3 to form SiOSi or SiCH2Si by releasing H2.关键词：SiC fibers;Polyaluminocarbosilane;Air-curing;SiH;Oxygen content
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发布时间：2021-03-19 - 摘要：Generalized two-dimensional infrared correlation spectroscopy (2D-IR) has been applied to the study of the curing reaction process of MDA-benzoxazine.The reaction has been monitored by in situ infrared heating accessory (in situ FTIR).In the in situ FTIR test,appropriate MDA-benzoxazine resin was coated uniformly in the bromine potassium piece and placed in a heating accessory.The heating rate was 2.06 K/min and up to 190 ℃,then hold the same curing temperature in 120 min.The FTIR spectra were processed by omnic and 2D-IR software of Thermo Fisher Company.Two products could be observed after thermal ring opening reaction:the intermediate with C=N bond does not continue the chain-extending reaction,and part of the them exhibits cracking reaction at high temperatures,then schiff alkali with C=N+ bond could be observed.The intermediates with carbonium ions were further cross-linking polymerized,and the polymers were comprised of hydroxyl,trisubstituted aromatic ether and mannich bridge structure.The orders of the key groups in the curing were given by 2D-IR,and the specific chemical structure of the polymer was comprised of trisubstituted aromatic ether and mannich bridge structure.关键词：MDA-benzoxazine;Heat curing;In situ FTIR;2D-IR
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发布时间：2021-03-19 - 摘要：For the sake of simplifying the processes of synthesizing polymer modified gadolinium-based MRI contrast agents,and preparing gadolinium-containing and temperature-sensitive polymeric microsphere in a facile way,we choose soap-free emulsion polymerization as a synthetic method.Temperature-sensitive polymeric microspheres are prepared by soap-free emulsion polymerization in the presence of temperature-sensitive monomer N-isopropylacrylamide and polymerizable gadolinium monomer.Transmission electron microscope tests show the monodispersity of the polymeric microspheres.The dynamic light scattering tests indicate that the hydrodynamic diameters of the polymeric microspheres are about 260 nm with narrow size distribution,the hydrodynamic diameters of the polymeric microspheres decrease by about 60 nm when temperature increases from 25 ℃ to 45 ℃,and the swelling ratio (defined as (Dh, 25 ℃/Dh, 45 ℃)3) is 2.06,indicating the good temperature-sensitive property of the polymeric microsphere.The contents of gadolinium in polymeric microsphere emulsion (solid content 1%) are 1 mg/L. In vitro T1-weighted ralaxivity (r1) at 3.0 T is 8.01 (mmol/L)-1 S-1,which is much higher than that of clinical gadolinium chelate (Gd-DTPA).The polymeric microspheres show great prospects in pre-clinical MR imaging.关键词：Gadolinium;Temperature sensitive;Polymeric microsphere;MRI
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发布时间：2021-03-19 - 摘要：Based on conventional Novolak phenolic resins,organic aerogels were prepared by sol-gel method.By optimizing the microscopic pore structure of organic aerogels through modifying concentration of the cross-linking agent of HMTA,the capillary force of solvent for wet aerogels during drying was obviously decreased.Thus,the aerogels could be easily obtained by ambient drying with slight shrinkage and well skeleton strength.The effects of HMTA on the microstructure of pores,apparent density,thermal stability,mechanical properties and other performances of organic aerogels were detailedly studied.The pore textural and morphological studies showed that the average pore diameter of organic aerogels decreased and the specific area increased with increasing HMTA concentration.When the concentration of HMTA was 0.2 mol/L,the average pore diameter of aerogel was up to 100 nm.The nano-scaled pore diameter and fine distribution of pore diameter can help to promote the stability of organic aerogels skeleton.Compared to the aerogel with micro-scaled pore diameter,the compression strength and modulus of aerogel with nano-scaled pore diameter were apparently improved.Because of the increase of HMTA concentration,lots of unstable NCH2 groups were incorporated into the phenolic aerogel,which may lead to the decrease of thermal stability for phenolic organic aerogel.关键词：Phenolic resin;Sol-gel;Organic aerogel;Pore structure;Thermal stability
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发布时间：2021-03-19 - 摘要：Ramie fiber cloth with excellent damping property and strong carbon fiber cloth were laid alternatively to prepare the epoxy resin matrix composites via VARAM (vacuum resin absorbable molding) process.Firstly,the mechanical properties were estimated,including the dynamic mechanical property,the static mechanical property and the impact crack toughness.Next,vibration characteristics were studied by the measurement of the resonance frequency and the damping factors.The results indicated that the contradiction between the damping properties and the mechanical properties could be balanced by the hybrid plies of the ramie fiber cloth and the carbon fiber cloth.Consequently,it was able to reach the purpose of controllable regulation of the damping properties and the mechanical properties and give full play to remarkable designing advantages of composites.Among them,the composite with RCRCR lay-up achieved loss factor as high as 0.0057,2.2 times more than that of the pure carbon fiber cloth composite,and tensile strength as much as 381.6 MPa,4.6 times more than that of the pure ramie fiber cloth composite.In the end,the structure of hybrid laminated composite was analyzed and the finite element analysis on damping properties were carried out in order to study the internal reason of influence of different plies on the mechanical and damping properties of the composite.Furthermore,the resonance frequencies and loss factors of the composites with other plies were predicted,and it could support some references for the design of the structural damping composites.关键词：Ramie fiber;VARM;Hybrid laminated composite;FEM;Damping
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发布时间：2021-03-19 - 摘要：Sulfonated poly(ether sulfone) (SPES)/Silica (SiO2) nanofibers were prepared by solution blowing process,and impregnated to Nafion matrix to prepare SPES/SiO2/Nafion composite proton exchange membranes (PEMs).The characteristics of the composite membrane,such as morphology,thermal stability,proton conductivity and performance of membrane as PEMs,were investigated.The results showed that the introduction of solution-blown nanofibers to composite membranes significantly improved properties of Nafion.The TG results showed all the composite membranes had better thermal stability than pure Nafion.Swelling ratios of all the composite membranes were lower than that of pure Nafion,and those of SPES/SiO2/Nafion-5,SPES/SiO2/Nafion-15 and SPES/SiO2/Nafion-25 were 14.9%,15.84% and 17.2% at 80 ℃,respectively.However,the swelling ratios of composite membranes increased with the increase of SiO2 content in nanofiber.Proton conductivity of the composite membranes increased first and then decreased with the increase of SiO2 content,and the membrane containing 15% SiO2could get 0.154 S/cm at 80 ℃ and 100% humidity.Besides,the methanol resistance was also greatly improved,methanol permeability of the composite membrane containing 25% SiO2decreased by 55.3% compared to that of Nafion.Therefore,the composite membrane containing hybrid SPES/SiO2 nanofibers can be considered as a promising PEM for fuel cell applications.关键词：Proton exchange membrane;Fuel cell;Nanofiber;Hybrid
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发布时间：2021-03-19 - 摘要：The ABC coil-rod-coil triblock molecules,consisting of biphenyl and phenyl units connected together with ether and ester bonds as a rod building block,and poly(ethylene oxide)s with DP of 7,12 and 17 and octyl or hexadecyl alkyl chains as flexible A and C coil segments,were successfully synthesized. These molecular structures were characterized by means of 1H-NMR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).The self-assembling behavior of these ABC coil-rod-coil triblock molecules was studied in bulk state,using differential scanning calorimetry (DSC),thermal polarized optical microscopy (POM),and small-angle X-ray scattering (SAXS).The experimental results showed that molecules 1a and 2a with poly(ethylene oxide) coil chains (DP=7) and linked together with octyl or hexadecyl chains,self-assemble into an oblique columnar (Ob) and a rectangular columnar (Rect) structure in the solid state and liquid crystalline phase,respectively.While,molecules 2b,2c and 1c containing longer poly(ethylene oxide) coil chains than 1a and 2a self-assemble into the oblique columnar nano-structures in the solid state.It was found that the lengths of the poly(ethylene oxide)s and alkyl chains dramatically influence the self-assembling behavior of this coil-rod-coil molecular system.Therefore,supramolecular nano-structures of coil-rod-coil triblock copolymers can be accurately controlled via tuning the length of the coil chains connected with the rigid rod building block.关键词：Self-assembly;Supramolecular structures;Triblock molecule;Phase behavior;Columnar nanostructure
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发布时间：2021-03-19 - 摘要：By amidation reaction,folic acid (FA) was grafted to hydrophilic polymer poly(glycidyl methacrylate)-g-poly(ethylene glycol)) (PGMA-g-PEG).Nuclear magnetic resonance (NMR) and infrared spectroscopy (FTIR) tests showed that polymer PGMA-g-(PEG)(FA)was successfully synthesized and the grafting level of FA was 1.7%.In order to prepare water-soluble quantum dots,the polymer PGMA-g-(PEG)(FA) was used to modify quantum dots (QDs) by ligand exchange.And using glutaraldehyde,the anti-cancer drug doxorubicin (DOX) was attached to the surface of the water-soluble quantum dots by the imine groups to form the final folic acid targeted theranostics system QDs@PGMA-g-(PEG)(FA)(DOX).UV-Visible spectra (UV-Vis) showed that the folic acid targeted theranostics system had the characteristic absorption peaks of QDs,DOX,and FA.The result illustrated that the folic acid targeted theranostics system was successfully prepared.The drug release study showed that the system was pH sensitive,had large drug release amount at pH 5.0,and was stable at pH=7.4.Hela cells experimental studies showed that compared with the theranostics system,the folic acid targeted theranostics system had greater cytotoxicity and higher concentrations of QDs in the cytoplasm and higher concentrations of DOX in the nucleus.All above,compared with the theranostics system,folic acid targeted theranostics system can be better applied to cell imaging and tumor treatment in the future.关键词：Folic acid;Quantum dots;DOX;Theranostics;pH-sensitive
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发布时间：2021-03-19 - 摘要：In order to study the kinetic characters of bulk end-cross-linking CuAAC click reaction,in situ FTIR method was employed to investigate the kinetics of PTPEG/GAP bulk end-cross-linking CuAAC click reaction based on the spectral character of PTPEG and GAP.The kinetics curves of PTPEG/GAP bulk end-cross-linking CuAAC click reaction were obtained on the basis of the relationship of the absorbance ratio at 2100 cm-1 and 1086 cm-1 changing with time.The results of fitting curves indicated that during the whole reaction,two obvious stages were observed.At 30 ℃,40 ℃,50 ℃ and 60 ℃,the first stage ended at 535 min,305 min,295 min and 115 min,respectively.Shear viscosity () results showed that the curves of changed along with reaction time showed an L-like shape.At 30 ℃,40 ℃,50 ℃ and 60 ℃,the inflection point of -t curves appeared at 540 min,320 min,305 min and 118 min,respectively.The inflection point time of -t curves was consistent with the end time of first stage of the PTPEG/GAP.Arrhenius equation fitting results indicated that the activation energy of the first stage corresponding to the reaction before gelation of PTPEG/GAP was (45.572.77)kJ/mol while that of the second stage corresponding to the reaction after gelation was (59.504.01)kJ/mol.关键词：Click chemistry;Propargyl-terminated poly(ethylene glycol) (PTPEG);Bulk end-cross-linking;Spectral analysis;Reaction kinetics
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发布时间：2021-03-19 - 摘要：On the basis of microwave treatment of chitosan solution,a convenient in situ method is established to form fluorescent carbon dots/chitosan composites which can be directly used in subsequent applications.This method has many benefits including prompt operation,simple equipment,simplified post-treatment,green process and low cost,and it allows a convenient way to gain carbon dots/chitosan nanocomposites that can be directly used for wide applications.The analysis results indicate that the carbon dots/chitosan composite solution is transparent and homogeneous.In addition,the carbon dots/chitosan composite solution displays brown color under visible light,while presents clear blue fluorescence under 365 nm UV light.Transmission electron microscopy test exhibits that carbon dots disperse well in the carbon dots/chitosan composite,and the average size of carbon dots is about 7.0 nm.Specially,the obtained carbon dots/chitosan composite not only has attractive properties(e.g.,multicolor fluorescence) that belong to carbon dots,but also retains the favorable properties(e.g.,pH-responsive properties) of chitosan.Based on these combined properties,it is convenient to employ the carbon dots/chitosan composite to construct fluorescent films by casting method,to prepare fluorescent beads by a convenient dropping procedure,as well as to generate fluorescent coatings on electrodes by electrodeposition technique.Furthermore,the carbon dots/chitosan composite can be directly applied to cell imaging.Thus,this carbon dots/chitosan composite constructed by in situ method has potential applications in fluorescent materials,electrodeposited coatings,drug carriers,bioimaging and biolabeling.关键词：Carbon dots;Chitosan;In situ method;Fluorescent material
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发布时间：2021-03-19 - 摘要：The thermo-oxidative aging experiments of natural rubber (NR) under different aging times were performed and the aging mechanism was analyzed.The possible group variations were studied by Fourier transform infrared spectroscopy.Meanwhile,two dimensional correlation analysis,which found that the rate of aging productions was esters peroxides ethers,was performed.Magnetic resonance crosslink density test was also carried out,the results showed that the total crosslink density (XLD),the average molecular weight between two cross-linking point (Mc),and the transverse relaxation time of crosslinking network (T2) matched well with each other.The XLD increased with the increase of the aging time,indicating that the crosslinking reaction dominated the thermo-oxidative aging of NR.The DSC result showed that with the increase of the aging time,the glass transition temperature(Tg) rose and the glass transition region widened.This result was attributed to the limited movement of chain segments,indicating the thermo-oxidative aging of NR was dominated by crosslinking reactions.Furthermore,compression stress relaxation experiments were carriedout and an amendatory standard linear solid (SLS) model was put forward to describe the compressive stress relaxation behavior of NR.It showed that the thermo-oxidative aging process of NR was dominated by the oxidation and the crosslinking reactions,which corresponded well with the crosslink density and DSC results.关键词：Natural rubber;Thermo-oxidative aging;Two dimensional correlation analysis;Standard linear solid model
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发布时间：2021-03-19 - 摘要：Novel microcapsules containing graphene /n-octadecane as core material and melamine-urea-formaldehyde polymer as shell material were prepared by emulsion polymerization with styrene maleic anhydride copolymer (SMA) used as emulsifier.The effects of graphene on the properties of n-octadecane microcapsules were studied.Surface morphology,crystallography and thermal properties of microcapsules were characterized and analyzed by using field emission scanning electron microscopy (FE-SEM),Fourier transform infrared spectroscopy (FTIR),Raman spectroscopy,X-Ray diffraction (XRD),thermal constant Hot Disk analyzer,differential scanning calorimetry (DSC),and thermal gravimetric analysis (TGA).The results indicate that the microcapsules are spherical and have relatively smooth surface.The particle size of microcapsules is about 1-30 m.In addition,the morphology of microcapsules has no obvious change the with 0.1 g graphene addition.Too much graphene intensifies the reunion of microcapsules.XRD shows that graphene in microcapsules does not change the crystallization peak position of microcapsules,which is good for the practical application of the microcapsules.Heat enthalpy and encapsulation of microcapsules decrease with the increase of graphene addition,but the supercooling phenomenon of core material has been observably improved.Heat transfer performance of microcapsules is markedly improved due to graphene.Thermal conductivity coefficient of microcapsules is 0.092 W m-1 K-1 with 0.2 g graphene addition,which is enhanced by about 51%,compared with the pure microcapsule.It illustrates that graphene may improve the heat transfer performance of traditional phase change microcapsules and promoted the application performance of phase change microcapsules.关键词：Graphene;N-Octadecane;Phanse change microcapsule;Thermal property
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发布时间：2021-03-19 - 摘要：With the poly(St-co-DMC) as template,TMOS as silicon source,the poly(St-co-DMC)/SiO2 hybrid nanoparticles were synthesized under ambient temperature and neutral pH conditions.The TEM result of sliced sample confirmed that the hybrid nanoparticles possessed core-shell structure and that the SiO2 deposited mainly in the shell of the nanoparticles.Furthermore,the hybrid nanoparticles were dissolved with tetrahydrofuran to obtain the hollow nanoparticles.TEM results showed that the polymer core of the nanoparticles disappeared,generating nanoparticles with hollow structure.In addition,FTIR results confirmed that the hollow nanoparticles had the signal of both SiO2 and polymer which indicated that this hollow nanoparticles not only contained SiO2 but also poly(St-co-DMC).The content of SiO2 in the hollow hybrid nanoparticles of poly(St-co-DMC)/SiO2 was only 69.7% analyzed by TGA,indicating a left of 30.3% of polymer,which further confirmed that the hollow nanoparticles possessed hybrid shell.Finally,the effect of the reaction temperature,deposition time,the proportion of polymer/TMOS and the content of DMC in polymer template on the thickness of the hybrid nanoparticles shell was studied by TEM.The results showed that the thickness of the hybrid nanoparticles shell increased with raising the reaction temperature, increasing the deposition time,the proportion of TMOS/polymer and the higher content of DMC in polymer template.关键词：Poly(St-co-DMC)/SiO2;Hybrid;Nanoparticles;TMOS;Biomimetic deposition
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发布时间：2021-03-19 - 摘要：The copper sulfide (CuS) nano-particles which have the photothermal effect were prepared by wet-chemical method.The polymer gel/copper sulfide[P(NIPAAm-co-NVP)/CuS](NNC/CuS) composite microspheres which possess both temperature sensitivity and photothermal effect were synthesized,using N-isopropylacrylamide (NIPAAm) and N-Vinylpyrrolidone (NVP) as monomers,laponite as crosslinking agents,then CuS nanoparticles were adsorbed.Drug delivery performance and drug controlled release properties were also studied.The results showed that both CuS nanoparticles and composite microspheres had a very wide spectral absorption band in the near infrared region.In the 980 nm (0.5 W/cm2) laser irradiation case,NNC/CuS composite microspheres exhibit a good photothermal effect,the temperature of composite microspheres can raise to 51.9 ℃ in 8 min.It can effetively kill Hela cell,the killing effect getting better with the increase of irradiation time.The drug loading is 0.15 mg/mg,the cumulative drug release rate is 75% at pH=5.5 PBS buffer and 63% at pH=7.4.The photothermal effect can also effectively regulate drug release from temperature sensitive drug loaded microspheres.In drug release phase,the drug release rate was much improved when treated with 980 nm laser irradiation.On the other hand,the cell toxicity of NNC/CuS composite microspheres was notably decreased.The cell viability of the composite microspheres was 90.9% compared with 63% of CuS nanoparticles.关键词：Microgel;Temperature-sensitive;Copper sulfide nanoparticles;Photothermal effect;Tumor cell;Drug release
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发布时间：2021-03-19
Research Article
- 摘要：In order to enhance the dispersion of multi walled carbon nanotubes (MWCNTs) in the epoxy resin (EP) and improve the interface properties of composite materials,polymerized ionic liquid (PIL) was synthesized using 1-vinyl-3-butylimidazolium hexafluorophosphate as monomer and then used to modify the surface of MWCNTs.The modified carbon nanotubes by PIL (PIL-CNTs) were characterized by thermogravimetric analysis (TG),Raman spectroscopy (Raman) and scanning electron microscopy (SEM).The results showed that PIL can be adsorbed on the surface of MWCNTs and not change the electronic structure of MWCNTs.The PIL-CNTs showed better dispersion in acetone than pristine MWCNTs.PIL-CNTs/EP was prepared by incorporating 0.5 wt% PIL-CNTs into EP with DDM as a curing agent.Analysis of dynamical mechanical properties,mechanical properties and morphology showed the presence of PIL improved the dispersion of MWCNTs and enhanced the mechanical property.In comparison with neat EP and MWCNTs/EP systems,PIL-CNTs/EP displayed substantially higher storage modulus,and glass transition temperature was also increased by 5.6 ℃ and 3.3 ℃ than those of neat EP and MWCNTs/EP,respectively.Compared to neat EP,he tensile strength,bending strength and impact strength of PIL-CNTs/EP composites increased by 35.2%,26.4% and 45.0%,respectively.The SEM images of fracture surface indicated the dispersion of PIL-CNTs in the matrix and the interfacial adhesion were obviously improved.关键词：Carbon nanotubes;Polymerized ionic liquids;Epoxy resin;Dispersion;Mechanical property
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发布时间：2021-03-19
Research Bulletin
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