最新刊期
卷 ， 期 11 ， 2010
- 摘要：Photonic crystals (PCs) in nature have been endowed many functions,such as fantasy structure colors,special wettabilities and high film strength.On the basis of our recent work inspired by these special functions of PCs in nature,this feature article introduced that polymer PCs with special wettabilities were fabricated by constructing core-shell polymer latex,adjusting the surface morphology of latex and other methods.PCs with high strength were prepared by photo-crosslinked among the polymer latex arrays.Anisotropic PCs were fabricated from mushroomcaped latex particle.Such functional PCs were further demonstrated applications in humidity sensing,oil sensing,self-oscillating system sensing,etc.Finally,largescale fabrication of functional PCs has been demonstrated by spray coating and ink-jet printing.Those studies will be of great importance for developing novel polymer PCs materials.
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发布时间：2021-03-19
Feature Articles
- 摘要：The adsorption of collagen on spin-coated poly(lactic acid) (PLA) surface was investigated using quartz crystal microbalance (QCM).The effects of concentration (0~9.25 g/mL) and temperature (10~50℃) on adsorption were studied.The results show that:with the increasing concentration of collagen,the adsorption amount and initial adsorption rate on spincoated PLA surface increases correspondingly.Langmuir model and Freundlich model were applied for data fitting.The isotherm equations q=1169(0.99c/1+0.99c) and q=610c(1/3.79) were obtained.It is found that Langmuir model described experiments better than the Freundlich model.The kinetic experimental data were correlated with the Lagergren pseudofirst order kinetic model and the Lagergren pseudo-second order kinetic model.It is shown that under low concentrations the Lagergren pseudofirst order kinetic model fits the results better and the Lagergren pseudosecond order kinetic fits the results better under high concentrations.It means that the diffusion process is the ratecontrolling step under low concentration and the interaction between collagen and PLA surface is the ratecontrolling step under high concentrations.The AFM images show that the collagen adsorbed on PLA surface formed meshlike structure.The adsorption was significantly influenced by temperature changes in the adsorption buffer,indicating that the collagen is a kind of temperaturesensitive material.The results also indicate that collagen denaturalizes gradually with increasing temperature in the range (10~40℃).The adsorption quantity drops sharply when the temperature approaches (40~45℃),40℃ is the denaturizing temperature of collagen under present experimental conditions.
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发布时间：2021-03-19 - 摘要：Proton exchange membrane fuel cells (PEMFC) have attracted considerable research interest for its advantages in cleaning energy such as no pollution and no warm house gas.Although the mostly investigated Nafion series products possess excellent properties,their low conductivity at high temperature and low humidity as well as their high cost is still limiting their application.In this work,a series of poly(vinylidine fluorde-co-trifluroethyleneco-chlorotriflurethylene)-g-sulfonated polystyrene P(VDF-co-TrFE-co-CTFE)-gSPS) copolymers with tunable graft densities and branch lengths are synthesized using commercial P(VDF-co-CTFE) via a route including partial hydrogenation,ATRP and sulfonation reaction.The structure and properties of these polymers are carefully characterized with NMR,TEM,water uptake and proton conductivity measurement.The influence of test condition and polymer construction on their properties has been well discussed.It has been shown that the graft density governs the phase separation of the resultant polymer,and therefore its water uptake and proton conductivity.The copolymer with low graft densities shows larger scale phase separation,higher water uptake and larger conductivity at low temperature.As temperature increases,the proton conductivity of the copolymer with low graft density increases.The copolymer with optimized composition exhibits even higher proton conductivity than that of Nafion-112 tested at a relative humidity over 50% in the same condition,temperature range 30~120℃.Therefore,it is expected to be an excellent PEM materials with low cost.
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发布时间：2021-03-19 - 摘要：The reaction of bisphenol A (BPA) with ethylene carbonate (EC) promoted by Bu2SnO at 180℃ produces dihydroxyethylbisphenol A (Ⅰ) along with the liberation of CO2.The influence of temperature on the reaction of EC and BPA is investigated by FTIR.The diol Ⅰ reacted with dimethyl carbonate (DMC) at 120℃ to generate bisphenol A carbonate (Ⅱ) in yield of 96%.Their structures were characterized by FTIR and NMR.A novel nonphosgene process for producing bisphenolA polycarbonate (PC) was developed through the self transesterification of Ⅱ and cotransesterification of Ⅰ and Ⅱ.The self transesterification of Ⅱ is much faster than cotransesterification of Ⅰ and Ⅱ. The reaction temperature strongly affects the molecular weight of polycarbonate.NMR,gel permeation chromatography (GPC),differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to measure the molecular structure and thermodynamic properties.The average number molecular weight of PC obtained from the selfpolymerization of Ⅱ for 6 h at 240℃ is up to 17.6103 .The Tg of PC (Mn = 12.4103) is about 60℃,which is much lower than that of the regular PC (Tg = 145~150℃).The introduction of CH2CH2 unit into the main chain can reduce the Tg of PC and increase the crystallization ability.The obtained PC has a good thermal stability.
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发布时间：2021-03-19 - 摘要：Porphyrinated poly(-stearyl L-glutamate)s(PSLGs) were synthesized by the ringopening polymerization of -stearyl L-glutamate N-carboxyanhdyride(SLGNCA) with 5-(4-aminophenyl)-10,15,20-triphenylporphyrin (APTPP) and corresponding zinc and cobalt porphyrins(ZnAPTPP,CoAPTPP) as initiators.Intrinsic viscosity measurement shows that the PSLGs initiated by CoAPTPP have much higher molecular weight than that by APTPP and ZnAPTPP.UV-Vis and fluorescence spectra of the porphyrinated PSLGs exhibited typical absorptions and emissions,which are consistent with those of the corresponding porphyrin initiators.These porphyrinated PSLGs were electrospun into microfibers from chloroform solutions.Well-defined microfibers,however,were obtained only from PSLG with high intrinsic viscosity that was prepared by CoAPTPP.The fabricated porphyrinated PSLG electrospun mats emitted red fluorescence uniformly regardless of their microstructures,whereas the intensities varied with the porphyrin attached in the polymer.The fluorescence intensities of PSLG mats containing APTPP and ZnAPTPP were very strong while that of PSLG mats containing CoAPTPP were very weak due to the fluorescence quenching of cobalt porphyrin.In combination of the unique optical property of porphyrin with biocompatibility of PSLG,the porphyrinated PSLGs and electrospun mats are potential for the applications in sensory material and drug delivery system.
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发布时间：2021-03-19 - 摘要：A polyimide with arylene sulphide structure units was synthesized via polycondensation of 4,4-diamino diphenyl sulphide (SDA) and pyromellitic dianhydrid (PMDA) followed by thermal imidization and chemical imidization.A real-time online tracing method was built up by using the advanced rheology expanded systems (ARES) to monitor the polycondensation,and the effects of reaction conditions on the thermal and chemical imidization were studied by thermogravimetic analysis.The structures and properties of the polyimide were characterized by fourier transform infrared spectroscopy (FTIR),small angle laser light scattering (SALS),contact angle analysis and differential scanning calorimetry (DSC) etc.Results show that the surface properties of polyimide films are great improved by introducing the arylene sulphide structure into the main chain of polyimide,and the adhesion work between the new polyimide and copper foil is higher than the traditional one.The weightaverage molecular weight of the polyimide is (6.71.6)104; the decomposition temperature is higher than 560℃; DSC results show that the polyimides prepared by both thermal and chemical imidization have high glass transition temperature,and in comparison,chemical imidization gives rise to a higher degree of imidization and a higher glass transition temperature.
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发布时间：2021-03-19 - 摘要：The bowl-shaped aggregates were prepared by using an azo polymer (BP-AZ-2CA),and their photoinduced deformation behavior was studied.The bowlshaped aggregates were prepared through gradual hydrophobic aggregation of the polymeric chains in DMF-H2O media and characterized by using TEM.critical water content (CWC) was obtained by the light scattering measurement.The results showed that two types of aggregates formed in the system,one was small colloidal spheres and the other was bowl-shaped aggregates.The aggregates with different average diameters were obtained by adjusting the initial polymer concentration and water-adding rate in the preparation processes.The photoinduced deformation behavior was studied by irradiating the bowl-shaped aggregates in solid state with a linearly polarized Ar+ laser beam (488 nm,110 mW/cm2) for different time periods.Upon the light irradiation,the bowl-shaped aggregates were elongated along the polarization direction of the laser beam especially when the irradiation time was longer than 15 min.The hollow space in the aggregates almost remained unchanged after irradiation.The morphology of the bowl-shaped aggregates after irradiation changed with the angle between the bowl-shaped aggregates and the polarization direction of the light beam.
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发布时间：2021-03-19 - 摘要：Ionic liquid1-(n-Octyl)-3-Methyl limidazolium hexfluorophosphate ［C8mim］［PF6］ was used as a structurecontrolling additive,and polysulfone (PSF) membranes with different structures were prepared by the wetphaseinversion in this work.The results indicated that ionic liquid ［C8mim］［PF6］ had important influence on the poreforming.With increase of concentration of ionic liquid ［C8mim］［PF6］ in casting solutions,the structures of the membranes changed from asymmetric finger pore,the lengthenedbig pore and the big caves to spongy pore.When the concentration of ［C8mim］［PF6］ was 4%,the membrane had the asymmetric fingerpores structure,the pore size close to its surface layer was about 2~6 m and that close to its sublayer was about 10~70 m,the retention rate and flux of PEG10000 were 92.3% and 33.7 L #12539; h-1 m-2.The analysis indicated that hydrophobic ionic liquid ［C8mim］ ［PF6］ could improve orderly arrangement of polysulfone molecules at the low concertration,while the strong delay of phase inversion appeared at the high concertration.It was found by X-ray EDS analysis of PSF membranes with SEM,ionic liquid ［C8mim］［PF6］ was partially retained in the prepared polysulfone membrane.This reduced the contact angles between water and polysulfone membranes,improving the hydrophilic properties of the membranes.Meanwhile,the formation mechanism of pore structures in the membrane preparation was also discussed,［C8mim］［PF6］ could restrain demixing of the casting solutions as a poreforming agent and plasticizer.
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发布时间：2021-03-19 - 摘要：The selective catalytic hydrogenation of living styrene-butadiene copolymer (SBS) prepared in the presence of metallocene catalyst modified by methyl benzoate was studied.The effects of factors,such as number-average molecular weight (Mn) of SBS,on the hydrogenation degree of the copolymers under different experimental conditions were discussed.The results show that when the ratio of Ti to 100 g dry copolymer is in the range of 0.15～0.3 mmol,adding methyl benzoate in a special mode can significantly improve the activity of titanocene catalyst.The hydrogenation degree of both SBS basic copolymers with Mn of 6.5104 and 5.5104 respectively are ＜97.0% after reaction for 180 min in the case of using metallocene catalyst not modified by methyl benzoate.On the other hand,the hydrogenation degree of the same SBS samples is 98.0% after reaction for 60～120 min under the condition of using the modified metallocene catalyst.In contrast with the similar researches reported before,our experiments could shorten the hydrogenation time by 60～120 min.When the ratio of Ti to 100g dry copolymer falls in the range of 015～0.3 mmol,the hydrogenation degree of the SBS basic copolymer is affected by magnitude of the Mn.For 30 min after the reaction,the hydrogenation degree of SBS copolymer with Mn of 5.5104 is 97.0% whereas that of the copolymer with Mn of 6.5104 is ＜90.0%.The disparity in hydrogenation degree between the two SBS copolymers is gradually diminished as the hydrogenation process proceeds and becomes unobvious after reaction for 180 min.In such a case the hydrogenation degree of both SBS basic copolymers are 98%.The effect of every influential factor on the hydrogenation degree of the SBS copolymers is elucidated in terms of the hydrogenation mechanism.
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发布时间：2021-03-19 - 摘要：Novel amino-terminated and anhydride-terminated hyperbranched polyimides (AMHBPI and ADHBPI) were successfully prepared by the two step method with a BB2-type aromatic triamine containing triphenylpyridine structure (TAPP) and a A2-type dianhydride,3,3,4,4-benzophenonetetracarboxylic dianhydride (BTDA) under microwave irradiaton.The chemical structure and properties of the resulting HBPIs were characterized by FTIR spectroscopy,1H\|NMR spectroscopy,XRD,TGA,solubility test,UV-Vis spectroscopy and fluorescence spectroscopy,respectively.The results showed that the resulting AM-HBPI and AD-HBPI were highly organosoluble in strong polar aprotic solvents and showed certain resistance to dilute inorganic acid corrosion.These polymers exhibited good thermal stability with the 10% weight loss temperature (Td10%) up to 573℃ and 568℃ in N2 atmosphere,respectively.Furthermore,the obtained AMHBPI and ADHBPI containing triphenylpyridine structure exhibited UV-Vis absorption bands in the region of 200~400 nm and 200~350 nm,as well as possessed strong purple and blue fluorescence,respectively.The UV-Vis absorption bands both extended to 425 nm and fluorescence intensity increased after the polymers were protonated with hydrochloric acid.As a result,these organosoluble novel hyperbranched polyimides containing triphenylpyridine structure were promising as high temperature resistant materials for organic photoluminescent,etc.,photoelectric applications.
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发布时间：2021-03-19 - 摘要：Toward exploiting cellulose nanofibrils with high aspect ratio and nano-order-unit interconnected web-like structure from poplar wood,a novel route was demonstrated,which combined the usual chemical procedures with high intensity ultrasonic treatment of the material in the waterswollen state.Firstly,lignin in the sample was removed using an acidified sodium chlorite solution.Secondly,the sample was treated with potassium hydroxide in order to leach hemicellulose.Lastly,the sample was processed with high intensity ultrasonication.Never-dried holocellulose,neverdried purified cellulose and wood cellulose nanofibrils (WCNF) were obtained,respectively.The changes of WCNF on the chemical composition,crystalline structure,crystallinity and morphologies during the preparation process were characterized by means of Fourier transform infrared spectroscopy (FTIR),X-ray diffraction (XRD) and scanning electron microscopy (SEM),and the diameter distribution of WCNF was further calculated and analyzed by image analysis method.The results showed that the main composition of WCNF was cellulose with crystalline structure of Ⅰ type,and the crystallinity of WCNF was 65.68%,12.33% higher than that of the raw material wood.The diameters,lengths and aspect ratio of WCNF were about 5~32 nm,longer than 10 m and larger than 300,respectively.The nanofibrils of WCNF were also interconnected into unique web-like structure.The characteristics including high crystallinity,high aspect ratio,nano-order-scale,web-like entangled structure,and so on,indicate that WCNF is a perfect reinforcing and toughening material.
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发布时间：2021-03-19 - 摘要：Novel double functionalized calix［4］arene derivative has been synthesized and used for the preparation of calix［4］arene containing PBTPDMS copolyester by polycondensation with hydroxy terminated poly(dimethylsiloxane),dimethyl terephthalate and 1,4-butanediol.1H\|NMR spectrum shows that the copolyester was comprised of calix［4］arene units,PBT and PDMS segments,which were linked by the 1,4-butanediol.The copolymerization efficiency of the comonomers was in the sequence of dimethyl terephthalatecalix［4］arene derivativePDMS.The weight average molecular weight of the copolyester was about 26000 Da,and the molecular weight distribution index was 1.9.A composite membrane of three-layer structure was prepared by casting the 21.2 wt% copolyester solution,in toluene onto a non-woven fabric supported microporous PAN membrane,and drying under reduced pressure.The SEM micrograph of the membrane shows that the thickness of the copolyester coating was about 90 m.The pervaporative removal of benzene from its dilute aqueous solution was studied using this composite membrane at different temperatures and original benzene concentrations.Due to the incorporation of calixarene units with adsorptive capability towards benzene moleculars the pervaporation membrane was excllent for benzene separation from dilute aqueous solution;the separation factor was 491 and benzne permeate flux 58 g/(m2h) using 10010-6 concentration at 40℃.
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发布时间：2021-03-19 - 摘要：The electrostatic compounding technology was used to prepare glass fiberSiO2 (GF-SiO2) and glass fiberMWNTs (GF-MWNTs) reinforcing fibers.Polyamide 6 (PA6)/GF-SiO2 and PA 6/GF-MWNTs composites were prepared by using a torque rheometer.The effects of compounded fibers on the mechanical,thermal properties and crystallization behavior of PA 6 were investigated via scanning electron microscope (SEM),differential scanning calorimeter (DSC),thermal mechanical analyzer (DMA) and tensile test.SEM photographs show that nano-SiO2 and MWNTs-COOH were uniformly dispersed on the surfaces of glass fibers.The interfacial adhesion between PA6 matrix and GF-SiO2,GF-MWNTs are better than that between PA6 and untreated GF due to the interaction such as hydrogen/covalent bonds formed among the functional groups of nano-particles and PA6 chains.Addition of GF and compounded fiber increased the crystallization temperature of PA 6,which indicated that GF and nanoparticles played the role of nucleating agent of PA 6.It was revealed that the PA 6/compounded fiber composites had higher tensile strength and dynamic storage modulus than those of PA 6/untreatedGF composites,especially the PA6/GF-MWNTs composites exhibited improved mechanical properties with 21% and 28% increases in tensile strength and dynamic storage modulus respectively.
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发布时间：2021-03-19 - 摘要：Monodisperse superparamagnetic polymer composite microspheres with high magnetite content were prepared by seed emulsion co-polymerization.In this system,0.7~0.8 m Fe3O4 magnetic aggregation droplets which were consisting of Fe3O4 nanoparticles with an average particle size of 10 nm were severed as seeds and droplets of styrene and divinylbenzene were used as monomers to swell the seeds before the polymerization.The influence of the swelling time on the morphology and magnetite nanoparticles content of the composite microspheres was also investigated.The obtained microspheres with diameter of 0.7~1.0 m were superparamagnetic and with the magnetite nanoparticles content of 29 wt%~57 wt%,which were extensively characterized by transmission electron microscopy (TEM),thermogravimetric analysis (TGA),Fourier transform infrared spectrometer (FTIR) and vibrating sample magnetometer (VSM).By adjusting the swelling time,a series of microspheres with different morphologies were also obtained and characterized.The result indicated that the degree of phase separation of the obtained microspheres increased when the swelling time decreased.On the other hand,the carboxyl group was introduced onto the surface of the above magnetic microspheres via a two-step seed emulsion co-polymerization using acrylic acid as a functional polymeric monomer.After that,the as synthesized superparamagnetic polymer composite microspheres with carboxyl groups (the density of carboxyl group was about 0.92 mmol/g beads) were conjugated with the bio-molecules (hCG was used as a model detection of bio-molecules in this study) and then applied into the chemiluminescence immunoassay.The obtained well performance showed the feasibility of the microsphere to be used as a potential and promising material for bio-detection.
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发布时间：2021-03-19
Research Article
- 摘要：PANI /TiO2 micro/nano spheres were prepared successfully by using octahedral cuprous oxide as the template.And TiO2 nano-particles are uniformly dispersed in polyaniline.Compared with the common template reported, Cu2O crystal is not only a new type of template in shape and quality，but also omits the need for posttreatment due to the soluble Cu2+ formed by the reaction of Cu2O with the oxidant during the polymerization process.The molar ratio of TiO2/ANI played an important role in controlling in morphology，electrical properties and the chemical structure of PANI/TiO2 composites.The results showed that the average diameters of PANI/TiO2 composites became smaller and smaller with the TiO2/ANI molar ratio increasing.The average diameters decreased from 373 nm to 80 nm when TiO2/ANI molar ratio increased from 0.16 to 1.6. The roomtemperature conductivity of PANI/TiO2 composites increased from 10-4 S/cm to 100 S/cm when TiO2/ANI molar ratio changed from 0.16 to 1.6，and then decreased softly when TiO2/ANI molar ratio was beyond 1.6. It is because that the oxidation state and protonation state of the PANI were affected by the TiO2/ANI molar ratio.The morphologies and chemical structures of the PANI/TiO2 composites were characterized by using scanning electron microscopy，transmission electron microscopy，infrared absorption spectroscopy and X-ray diffraction.
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发布时间：2021-03-19
Research Bulletin
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