最新刊期
卷 ， 期 4 ， 2009
- 摘要：Polymerization of a phenylacetylene monomer bearing a dendron moiety was carried out by using a rhodium complex Rh［(nbd)Cl2］2 as catalyst.The structure of the resultant was characterized with infrared (IR),nuclear magnetic resonance (NMR),and UV-Visible absorption spectroscopic techniques; the experimental data confirmed the generation of the expected polyphenylacetylene derivative (P1) with dendron pendants.P1 was soluble in common organic solvents such as chloroform,N,N-dimethylformamide oxide,and tetrahydrofurran (THF),and its average molecular weight was about 57300 The steric repulsion of between the bulky dendritic side chains make the polymer main-chain take a stereoregular cis-cisoid conformation.Consequently,P1 exhibits a pronounced shoulder at around 440 nm in the absorption spectrum its THF solution.Meanwhile,the bulky dendrons around the polymer mainchain protect the main-chain from thermalinduced decomposition via the “jacket effect",thus P1 lost 5% of its weight at a temperature of 295℃,which is about 70℃ higher than its parent polymer,or polyphenylacetylene.
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发布时间：2021-03-19
Rapid Communications
- 摘要：Self-assembly of block polymers under confined states is found to be affected by various parameters,such as the geometry and surface effect of confined states,which make the phase behavior of polymers under confined states different from those in bulk state.A stack of novel nanostructures have been fabricated by the self-assembly of block polymers under confined states.Furthermore,to study the self-assembly process of block polymers under confined states could give a deep understanding on the phase behavior of block polymers.The similar or covered phase behaviors in bulk state could be clearly distinguished under confined states.In this review,the cylinderforming linear block polymers are detailed studied using computer simulation methods.The geometry and surface fields of confined states and the component of polymer chains are considered separately.
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发布时间：2021-03-19
Reviews
- 摘要：Although there are obvious advantages and benefits in generating fluorinated acrylate (FA) polymers via emulsion polymerization,their incorporation into colloidal particles is not straightforward.The current studies offer a simple synthetic approach which nucleated directly in the monomer droplets and prevented the diffusion of hydrophobic C-F monomers from monomer droplets through the aqueous phase to micelles.In this paper,the cationic copolymer emulsion based on FA,SMA,and MMA was successfully synthesized via miniemulsion polymerization.Size distribution analyzer and transmission electron microscope were used to study the particle size and morphology influenced by ultrasonic amplitude,ultrasonic time and mole ratio of costabilizer hexadecane (HD) to total surfactants,respectively.The results showed that particle size was changed in the range of 80～150 nm,and various particle morphologies were obtained,such as core-shell,snowmanlike and strawberry-like.Long fluoro chains can result in the micro-phase separate which is beneficial to improving the water and oil-repellency.The static water contact angle on the cotton treated with the cationic emulsion of 1.0 wt% solid content can nearly reach to 150°.
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发布时间：2021-03-19 - 摘要：Resin copolymerized by n-butyl methacrylate (BMA) with β-hydroxyethyl methacrylate (HEMA) was synthesized in polymerization kettle,and functional fiber absorbing organic liquid was prepared by gelation-spinning in a twin screw spinning machine,then the influence of mass fraction of HEMA in monomer feed ratio on swelling behaviors was investigated and dynamic mechanical performance of the fiber was analyzed by dynamic thermomechanmetry (DMA),finally the surface and cross section morphologies were observed by scanning electron microscopy (SEM).The results showed that the fiber had the function of absorbing toluene and trichloroethylene after introducing HEMA into macromolecules, and the absorptive process obeyed Hill equation of sigmoidal model.Toluene and trichloroethylene absorbency increased with the increase of mass fraction of HEMA,and their maximum absorbency was 10 g/g and 21 g/g,respectively.The ratio of remaining fiber also increased with the increase of mass fraction of HEMA to make organic liquid retention ratio strengthen.Furthermore,dynamic mechanical performance of the fiber was affected by mass fraction of HEMA obviously, and the segments movement was influenced more obviously.At the same time,mass fraction of HEMA had a great impact on the surface and cross section morphologies,especially,many cavities existed in surface, and cross section had a lot of holes with asymmetric size when mass fraction of HEMA was equal to 15 wt%.
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发布时间：2021-03-19 - 摘要：A new type of charring agents,triazine-based crosslinked polymers,was synthesized through a polymeric reaction of trisglycidylisocyanurate and melamine in a melt state,and displayed good thermal stability and water resistance.The preparation process was feasible at ease,free of solvents and harmful released materials.The generated polymer was combined with ammonium polyphosphate(mass ratio 1∶5) to offer an intumescent flame retardant,which further was applied to polypropylene for flame retardant tests.When the intumescent flame retardant was loaded with 32% mass of the flame retarded polypropylene,burning tests and analysis showed that the resultant char layers exhibited continuous and compact structures,the oxygen limited index was 32,the vertical burning reached FV-0 level,and the peak heat release rate was 486 kJ/m2,in comparison with pure polypropylene,decreased by 47.5%,while the burning time with flame 714 s increased by 54.9%.
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发布时间：2021-03-19 - 摘要：The hydrophobicity,hydrophobicity recovery at different temperature,mechanical and electrical performance of hightemperature vulcanization silicone rubber (HTV-SR) exposed to needleplate electrode corona discharge were investigated,and the damage phenomenon and molecular structure change of silicone rubber by corona discharge were also studied by using scanning electronic microscope (SEM) and fourier transform infrared spectrum conjunction with attenuated total reflection (ATR-FTIR).The test results show that there is clearly hydrophobicity decreasing and temporality losing at the surface of HTV-SR after corona discharge,and it is unable to recovery to the initial level.The higher is the temperature,the faster is its hydrophobicity recovery velocity.The static contact angle increases with the increasing of corona aging time,corona discharge leads to a sharp reduce of volume resistivity and dielectric strength,the dielectric loss angle is growing fast.The main damage phenomen on of silicone rubber caused by corona discharge is the black dust corona ring on the surface ,whose diameter increases on the surface at first and then turn to depth direction combined with electrical erosion.The relative content of Si—O—Si,Si—CH3,C—H show downtrend with the increase of corona aging time.It is the representation that the tensile strength and hardness descend,the defect and hole on the surface increase.
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发布时间：2021-03-19 - 摘要：A hyperbranched polysilazanes(HBP) with multifunctionality of allyl end groups was prepared by polymerization reaction via hydrosilylation of AB2 type monomer(N-diallyamine) dimethlsilane,which was synthesized by aminolysis of Me2HSiCl.The molecular structure of HBP was characterized and determined by FT-IR,1H-NMR spectra analysis and GPC.Further more,the photo-initiated curing kinetics of HBP with thiol compound was studied by differential photoscanning calorimetry (DPC) technology.The comparing analysis among HBP,HBP-thiol compound and low-functionality monomer of B2M -thiol compound indicated that thiol functional group reacts with allyl functional group quickly under lower amount of photoinitiator (0.1 wt%) and lower light intensity (about 5 mW/cm2) in ambient condition.The curing rate and ultimate conversion of allyl group in HBP-thiol compound is higher than that in HBP,however,the ultimate conversion of allyl group in HBP-thiol compound is lower than that in B2M- thiol compound due to the unique hyperbranched structure and high multifunctionality.The effects of photoinitiator concentration ［A］,UV light intensity (I0) and reaction temperature on the UV curing rate and the final allyl bond conversion of HBP-thiol compound system were also investigated by DPC.The results indicate that the effects of photoinitiator concentration (［A］),UV light intensity (I0) and temperature on kinetics of HBP-thiol compound reveal that the curing rate (Rp) is directly proportion to square root of ［A］ and I0,respectively,which is found to fit with theoretical predictions very well at ［A］ no more than 050 wt% and I0 lower than 19.40 mW/cm2 Kinetics parameters were determined for HBP-thiol compound according to an autocatalytic model with a diffusion coefficient attached.The total apparent reaction exponent and apparent activation energy are 8.76 and 13.49 kJ/mol,respectively.
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发布时间：2021-03-19 - 摘要：Ring-opening metathesis polymerization (ROMP) with functionalized chain transfer agent (CTA) for the preparation of telechelic polymers has the ability to control the polymer molecular weights through varying the ratio of monomer to CTA.The bromo-terminated telechelic polymer (Br-PNBEDE-Br) was prepared via ROMP of norbornene derivative,in conjunction with a CTA in［bmim］［BF4］.The obtained polymer was characterized by 1H-NMR spectroscopy.The alkene proton signals of the norbornene ring appeared approximately at δ=6.24.Upon ring-opening and subsequent polymerization,these proton signals shifted upfield to approximately δ=5.64～5.16,this indicated the polymerization had occurred.The resonances of methylene protons adjacent to the ester bond (CHCHCH2OCO) shift from δ＝4.82 in the CTA to δ=4.56 in the polymer.These characteristic 1H-NMR resonances indicated that the CTA have been incorporated into the polymer chain.Furthermore,other types of end-groups were not observed in their expected regions of the 1H-NMR spectroscopy.Thus,the polymer should be a difunctionalized telechelic polymer with a high degree of bromine end functionalization.Based on using of the bromo-terminated telechelic polymer as macroinitiator,amphiphilic ABA triblock copolymer was synthesized by atom transfer radical polymerization (ATRP) of 2-dimethylamino)ethyl methacrylate (DMAEMA) in ［bmim］［BF4］.The formation of the copolymer was verified through the characteristic resonances of OCH2CH2N and N(CH3)2 protons from the block of PDMAEMA at δ＝2.63～2.52(Hp) and δ＝2.35～2.24(Hq),respectively,and resonances of methyl protons of C(CH3) from the same block at δ＝1.12～0.80(Hk).The integration area ratios of these characteristic resonances of 2.00∶5.96∶2.92 were well agreed with the ratios of corresponding protons of 2:6:3.The molecular weights of the copolymers were calculated by comparing the integral intensity of the methylene protons (Hp) of PDMAEMA at δ＝2.56 to the combined integral intensities of the methylene protons from both PNBEDE and PDMAEMA at δ＝4.05(He and Hl).The GPC curve showed a monomodal molecular weight distribution of the triblock copolymer prepared from ROMP macroinitiator.After polymerization,the molecular weight of the copolymer is shifted to high molecular weight position,and no peak attributed to the starting macroinitiator was observed,which means the ROMP macroinitiator used has been completely converted to the ABA triblock copolymer.The molecular weight of the triblock copolymer obtained by GPC analysis (Mn,GPC) was slightly lower than that estimated by NMR (Mn,NMR),and the triblock copolymer has reasonable low molecular weight distribution with a PDI of less than 1.40.The prepared triblock copolymer PDMAEMA90PNBEDE8-PDMAEMA90 (Mn,NMR=33100) can selfassemble spontaneously in H2O to form polymeric micelles,which were characterized by DLS,AFM,and TEM techniques.DLS measurements were used to estimate the hydrodynamic diameters of the micelles in aqueous solutions.The hydrodynamic diameter of the micelles was in the range of 183～236 nm with the increasing of pH value from 4 to 9.The morphology of copolymer was examined in preliminary investigations by AFM.In the AFM image,one can see many separate and densely deposited particles as spherical morphology on the mica surface,the spherical particles appear to be comparatively uniform in size,i.e.,they are essentially monodisperse with an average diameter of 600 nm,while these nanoparticles exhibited collapsed shapes on the mica surface with average height of 35 nm.Further evidence for the formation of triblock copolymer was obtained by TEM analysis.The projection of the micelles is circular,and the micelles must be spherical with the overall diameter of around 50,30 and 100 nm at pH 4,7 and 9,respectively.
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发布时间：2021-03-19 - 摘要：The micrographs of epoxy resin on single carbon fiber at room temperature and the temperature dependent contact angle on single carbon fiber were investigated using field environmental scanning electron microscope (FESEM).The results showed that the contact angle decreases significantly with increasing temperature.The advantage of this experimental approach was that can directly reflected the wettability of epoxy resin to fiber.But the experimental process was complicated,and there were many influence factors.The reason is that the wettability of epoxy resin on parallel sheet can be improved at higher temperatures.The spreading procedures for the epoxy resin droplet on carbon fiber cluster were observed by means of drop shape analysis system (DSA) in parallel and perpendicular directions of the aligned fibers.It was found that the temperature dependent contact angles were quite distinct from the different observed directions.Moreover,the contact angles observed perpendicular to the direction of fibers are consistent with the results on the single carbon fiber,which indicates that the wetting behavior of epoxy resin to the fiber in the direction parallel to the fiber cluster can truly represent the wettability.Then,the complicated method about single fiber of using FESEM to understand the wettability of epoxy resin to fiber could be replaced by using DSA.It should save much time and energy for the practical industry.
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发布时间：2021-03-19 - 摘要：Biodegradable aliphatic polyesters such as poly(glycolide) (PGA),poly(L-lactide)(PLA),poly(ε-caprolactone) (PCL) and their copolymers have been found widely applications in sutures,tissue engineering,bone fixation and controlled drug delivery due to their excellent biocompatible and biodegradable properties.But the shortage of functional pendant groups and low hydrophilicity limited their further applications.In this work,we explored a synthetic strategy of aliphatic polyesters functionalized with the pendant carboxylic groups through the ring-opening polymerization of novel functionalized lactone.First,2-ethoxycarbonylmethyl-cyclohexanone was synthesizedvia nucleophilic addition.Second,6ethoxycarbonylmethyl-ε-caprolactone(ECL) was generated by the Baeyer-Villiger oxidation of the 2-ethoxycarbonylmethylcyclohexanone.Then,homopolymer and copolymers were accomplished in bulk (130℃) by ring-opening polymerization in the presence of stannous 2-ethyl hexanonate Sn(Oct)2) as catalyst.All the polymers were characterized by FTIR,1H-NMR,13C-NMR,GPC,and DSC.The melting temperature (Tm) decreased with an increase of ECL content because the molecular weight decreased in corresponding.It was also noted that ΔHm for copolymers increased with an increase in the molecular weight because the relative number of copolymer chain ends and pendant functional groups decreased with a decrease of content of ECL.We think the availability of pendent groups on poly(ε-caprolactone) has great potential for applications in medicine,surgery,and tissue engineering.
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发布时间：2021-03-19 - 摘要：A zwitterionic monomer of 4-vinylpyridine propylsulfobetaine (4-VPPS) was prepared by the ring opening reaction of 1,3-cyclopropanesultone (PS) with 4-vinylpyridine (4-VP) at 80℃ for 20 h.Zwitterionic copolymers P(AM-co-VPPS) containing sulfobetaine groups were synthesized by copolymerization of acrylamide (AM) and 4-VPPS in aqueous solutions.The effects of 4-VPPS mole fraction in total monomer,the amount of initiator,total monomer concentration and reaction temperature on intrinsic viscosity of copolymers were investigated.The structure and composition of the copolymers were characterized by FTIR spectroscopy and 1H-NMR.The reactivity ratios of rl (AM)and r2 (4-VPPS) had been determined to be 2.01，8.71 and 1.99,8.44 according to Finemann-Ross equation and Kelen-Tudos equation,respectively.The experimental results showed that the intrinsic viscosity of copolymers reached the maximum value 656.4 mL/g when the reaction took 12 h at 20℃,with 0.03 wt% initiator concentration,2% 4-VPPS mole fraction in total monomer and 30 wt% total monomer concentration.The experimental results from viscometry indicated that copolymers P(AM-co-VPPS) exhibited typical anti-polyelectrolyte behavior,i.e.,the intrinsic viscosity of the zwitterionic copolymer increased with increasing the amount of low molecular weight electrolytes added regardless of NaCl or CaCl2.The increase of the intrinsic viscosity of copolymers P(AM-co-VPPS) in brine compared to that in the deionized water was strongly influenced by species and concentration of salts and the 4-VPPS mole fraction percentage in the copolymer P(AM-co-VPPS).As for copolymer P(AM-co-VPPS) containing 10.2 mol% 4-VPPS,the intrinsic viscosity increased by 47.3%,56.7% and 56.8% respectively in 1 mol/L NaCl,2 mol/L NaCl and 2 mol/L CaCl2 compared to that in deionized water.The zwitterionic copolymers with brine induced viscosifying effect could be used in enhanced oil recovery.
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发布时间：2021-03-19 - 摘要：A new radiopaque polyurethane was prepared via the blocking reaction between 4-iodoaniline and polycarbonate polyurethane with excess isocyanate groups.The development effect of modified polyurethane was characterized by X-radiography.The thermal behavior of the polymer was characterized with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).The cytotoxicity was tested by the method of thiazolyl blue (MTT) colorimetric assay using mouse fibroblast.Meanwhile,the development effect,relative molecular weight and mechanical properties of radiopaque polyurethanes with different iodine content were also studied.The results showed that the development effect of modified polyurethanes increased with the iodine content increased.It had a good radiopacity almost equivalent to that of a 2 mm thick aluminium wedge when the iodine content was 3.5 wt%.When the iodine content was less then 3.5 wt%,the number average molecular weight of which was in the molecular weight range of the usual thermoplastic polyurethane elastomer (Mn3×104),and they also had good mechanical properties and thermal stability.Degradation characteristics as observed from the TGA remained unchanged compared the unmodified polyurethane.The cell proliferation rate (RGR) of all modified polyurethanes was more than 75%,they were all biomaterials without cytotoxicity.This study provides a sample modification way for preparing radiopaque polyurethane which is expected to have significant advantage over their non-radiopaque counterparts in many medical and related applications.
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发布时间：2021-03-19 - 摘要：A series of sulfonated poly(arylene ether sulfone) (SPAES) copolymers with different degree of sulfonation (Ds) were synthesized by aromatic nucleophilic polycondensation of 3,3′-disulfonate 4,4′-dichlorodiphenylsulfone (SDCDPS),4,4′-dichlorodiphenylsulfone (DCDPS) and 4,4′-biphenol (BP).Synthesized sulfonated copolymers were characterized by FT-IR,TGA and DSC.Moreover,the microstructure of membranes was investigated by TEM,and the relationship between structure and performance was established.The influence of different Dson the properties of SPAES membranes was studied,and it showed that the increase of sulfonated groups in the polymers led to the increase of water uptake,ion exchange capacity (IEC),methanol diffusion coefficient and proton conductivitie of the membranes.Physical and electrochemical performances of all membranes were studied thoroughly.The results showed that the proton conductivity of SPAES-2 membrane was 0.116 S/cm at 80℃ and 0.126 S/cm at 100℃,which were higher than those of Nafion 117 membrane (0.114 S/cm and 0.117 S/cm).However,the methanol diffusion coefficient of SPAES-2 membrane only reached 8.4×10-7 cm2/s and was much lower than that of Nafion 117 membrane (2.1×10-6 cm2/s).The new synthesized membranes displayed good potential in application as proton exchange membranes (PEM) in proton exchange membrane fuel cells (PEMFC) and direct methanol fuel cells (DMFC).
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发布时间：2021-03-19
Research Article
- 摘要：A propylene-ethylene copolymer Versify2300 with 12 wt% ethylene content（V-2300） was multi-monomer melt grafted using maleic anhydride and styrene (MAH-St) by extruder.The effect of the addition of Versify-g-(MAH-co-St) (g-V-2300) on the compatibility of PA6/(V-2300+g-V-2300)(70/30) blends was investigated by means of SEM,FTIR and mechanical property measurements.The results showed that with increasing the g-V-2300 content,the size of the V-2300 dispersed phase became smaller and more uniform.Wheng-V-2300 is 25 wt%,the dispersed phase size is only 0.27 μm,and the izod impact strength of the blend is 324.54 J/m and is 16 times larger than that of the blend without g-V-2300.The addition of g-V-2300 remarkably improved the mechanical properties of PA6/(V-2300+g-V-2300)(70/30) blends including elongation,tensile strength and flexural strength.Thus toughened Nylon 6 alloys could be achieved with balanced mechanical properties.
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发布时间：2021-03-19 - 摘要：Two BrΦnsted acidic ionic liquids with an alkyl —SO3H functional group,1-methyl-imidazoliumpropanesulfonic acid hydrogen sulfate (［MIMPS］［HSO4］) and pyridiumpropanesulfonic acid hydrogen sulfate (［PYPS］［HSO4］) were firstly synthesized.And then the polyamiline (PANI) doped with these Br-nsted acidic ionic liquids were synthesized by a solventfree mechanochemical route.The structures and properties of PANI［MIMPS］［HSO4］ and PANI［PYPS］［HSO4］ were characterized. Because BrΦnsted acidic ionic liquid has four kinds of ionic form,in which hydrogen ion can exist independently,anilinium salt formed after the aniline was mixed with the ionic liquid. Reactions between anilinium salt and the oxidant,ammonium peroxydisulfate,resulted in PANI formation on grounding the reactants in a mortar. FTIR and UV-Vis-NIR spectroscopy indicated that PANI was formed in its doped,conductive emeraldine oxidation state and this was consistent with the green color of the products. The molar ratio of aniline monomer to ionic liquid was systematically varied in order to optimize the electrical conductivity of PANI. When the aniline monomer to ionic liquids ratio was 1:1,the highest electrical conductivity for the PANI-［MIMPS］［HSO4］(10.3 S/cm) and PANI［PYPS］［HSO4］(8.8 S/cm) was obtained,respectively. The XRD patterns of the resultant PANI showed two broad peaks at 10.1°,27.1°,two sharp peaks at 20.6°,25.4° and a weak peak at 29.1°,indicating that the resulting polymers were in the form of a highly doped emeraldine salts and have good crystallinity. Cyclic voltammograms of PANI showed two clear oxidation peaks in the forward scan and prominent reduction peaks in the reverse scan.The results demonstrated PANI-［MIMPS］［HSO4］ had better crystallinity,conductivity and electrochemical activity compared with PANI-［PYPS］［HSO4］.
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发布时间：2021-03-19 - 摘要：VCL/GMA-EDA-β-CD copolymer microgels were synthesized by surfactantfree precipitation copolymerization of N-vinylcaprolactam (VCL) with a monovinyl β-CD monomer (GMA-EDA-β-CD) in aqueous solutions.The VCL/GMA-EDA-β-CD copolymer microgels were characterized via transmission electron microscopy (TEM),Fourier transfer infrared spectroscopy (FTIR), 1H nuclear magnetic resonance (1H-NMR) and dynamic laser light scattering (DLS).The results indicate that addition of GMA-EDA-β-CD could reduce the particle size and size distribution of the copolymer microgels.The VCL/GMA-EDA-β-CD copolymer microgels exhibit thermally responsive changes in particle size in aqueous solutions,but incorporation of the β-CD monomer into a PVCL microgel could weaken its thermal sensitivity.
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发布时间：2021-03-19 - 摘要：A new and convenient approach for surface immobilization of heparin onto PE porous membranes is reported.3,4-dihydroxy-L-phenylalanine (L-DOPA),a catecholic amino acid,is an important component of mussel adhesive proteins (MAPs).Based on the strong adhesive behavior of poly(DOPA) on solid surface,hydrophobic PE porous membranes was surfacemodified by self-polymerization of L-DOPA in aqueous solution.Subsequently,heparin was immobilized covalently onto PE/poly(DOPA) composite membranes by the coupling between heparin and poly(DOPA) layer.The immobilization of poly(DOPA) and heparin was confirmed by X-ray photoelectron spectroscopy (XPS).The results of water contact angle measurements showed that the hydrophilicity of PE membranes was significantly improved by the introduction of poly(DOPA) and heparin.The effects of poly(DOPA) and heparin on membrane surface morphologies were also investigated by scanning electron microscopy (SEM).Despite the decreased pore amount and pore size on membrane surface after-poly(DOPA) and heparin immobilization,the improved hydrophilicity would be beneficial to promote permeability and biocompability of PE membranes.
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发布时间：2021-03-19 - 摘要：Acrylic acid (AA) and sodium styrene sulfonate (SSS) were grafted onto poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) membranes by preirradiation method,and a humidity sensing membrane with strong acid and weak acid groups was prepared.Grafting was carried out by using γ-ray from 60Co at room temperature.Thermal and chemical properties of the grafting membranes were investigated.Infrared spectroscopy analysis of the grafting membrane confirmed the existence of sulfonate and carboxylic acid groups in the grafting membranes.The thermal behavior of grafting membranes was evaluated by TGA,and the results show that the higher the grafting yield is,the higher the char residue,which indicates that the branch chains including —SO3Na and —COOH provide catalytic impetus to the charring.The degree of crystallinity of grafting membranes containing —SO3Na and —COOH groups decreased with the increase of the grafting yield.The static contact angle with water of the grafting membrane decreases meanwhile the hydrophilicity of the grafting membrane increases with increasing the grafting yield.The electrical response properties of the grafting membrane to humidity was examined,too.The resistive of the grafting membrane changes linearly by 3 orders of magnitude over almost the whole humidity range (5%～98%RH).Furthermore,the grafting membrane exhibits a quick response (absorption:less than 1 min; desorption:less than 2 min) and small hysteresis (less than 3%RH).The FEP-AA+SSS membrane can be a promising approach to the development of new humidity sensitive materials with good sensing characteristics.
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发布时间：2021-03-19
Research Bulletin
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