最新刊期
卷 ， 期 1 ， 2010
- 摘要：In order to simplify the synthesis procedure,,-bis(3-aminopropyl)-poly［(3,3,3-trifluoropropyl)methylsiloxane］ (FPS) was directly synthesized from 1,3,5-trimethyl-1,3,5- tris(3,3,3-trifluoropropyl)cyclotrisiloxane and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane via anionic ring-opening polymerization.The FPS modified polyure thaneureas (FSPUU) were further synthesized with poly (tetramethylene)glycol (PTMG)/FPS as mixed soft segments,and 4,4-methylenediphenyl diisocyanate/ethylene diamine as hard segments.Surface properties of the polyurethanurea(PUU) specimens measured by contact angle measurements,attenuated total reflectance Fourier transform infra-red spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) indicated that the surface hydrophobicity of the FSPUU films increased with increasing the content of FPS due to the enrichment of fluorine atoms at the surface region.Morphological studies through FTIR and DSC revealed that the incorporation of FPS segments into PUU macromolecular chains induced phase mixing.The oxidative stability of the FSPUU examined in vitro by immersing the films with 200 m thickness in an oxidative solution (H2O2-CoCl2) showed that the degree of degradation for all FSPUU films was lower than that of PDMS modified PUU (MSPUU),and the oxidative stability for these FSPUU films was fairly enhanced with increasing the content of FPS,which could be attributed to the lowering of swelling ratio in H2O and H2O2 as well as the permeation rate of H2O in FSPUU films.Furthermore,the tensile strengths of all FSPUU films are higher than those of MSPUU films.
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发布时间：2021-03-19 - 摘要：star-shaped poly(methyl methacrylate) with polyhedral oligomeric silsesquioxane (POSS) as a core was synthesized by atom thansfer radical polymerization (ATRP),using octa(-chloropropyl) POSS as a initiator and CuCl/2,2-bipyridine as catalyst system-Octa(-chloropropyl) POSS was prepared in methanol through the hydrolysis and condensation of chloropropyltriethoxysilane,and a yield of 28% was obtained.The welldefined structures of POSS and POSS/PMMA composite were fully characterized by FTIR,NMR,GPC and XRD,with results showing POSS molecule was successfully formed,and the mono-dispersion of POSS was achieved by ATRP,meaning that there was only one POSS molecule in a polymer chain.The polydispersity indices (PDI) of POSS/PMMA composite with different polymerization time were 1.20 and 1.14,according to the measurement of GPC.The TGA results indicated the thermal stability of POSS/PMMA composite enhanced from 281℃ to 303℃ with the increase of POSS content,which was due to the incorporation of POSS molecules
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发布时间：2021-03-19 - 摘要：Surface modification of polyurethane(PU) by appropriate treatment and introducing silane coupling agent to PU surface was used to improve the adhesion of PU to silicone rubber (SR).FTIR and X-ray energy spectrometer were employed to investigate the surface treatment and graft reaction of silane coupling agent,while surface morphology and properties of materials were characterized by scanning electron microscopy and water contact angle.Different PU/SR interfaces after oscillation and shear were compared as well.The results indicated that the hydrophilicity of PU was improved after surface treatment,which generated more hydroxyl groups that could react with isocyanate-terminated silane coupling agent.When condensed room temperature vulcanized SR was poured onto PU surface,the silane coupling agent on PU surface could condense with it to improve the adhesion of PU and SR by connecting them with chemical bonds.
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发布时间：2021-03-19 - 摘要：An ABA block polymer,double polyester capped aniline trimer was synthesized by the reaction of double aminocapped aniline trimer and -caprolactone with stannous octoate as catalyst,via ringopening polymerization in anhydrous toluene solution.The molecular weight of the obtained polymer was ca.5.9103,calculated through 1HNMR,very close to the data collected by gel permeation chromatography (GPC:Mn=5.0103,Mw=5.8103,DMF as solvent).The structure of the polymer was characterized and verified by 1H-NMR,FT-IR,UV-Vis,cyclic voltammetry (CV) and GPC.The polymer obtained has good solubility in common organic solvents.Both thermostability and electrostability are enhanced,compared to aniline trimer.Especially,the polymers sensibility to pH value is superior to the standalone aniline trimer.The color of the polymers solution can be changed from violet to cyanic (from pH=7 to pH=5).When the pH value is adjusted from 7 to 8,the solution color is bleached greatly.However,the standalone aniline trimer responds only to acid solution,with the color from royal purple to turquoise.The enhancement of both stability and sensibility gives the polymer more opportunity to be used as sensor materials.
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发布时间：2021-03-19 - 摘要：The blended films of polyurethane and silk fibroin (PU/SF) were prepared successfully by mixing water polyurethane (WPU) with silk fibroin solution.The structure of the blends was analyzed by means of FTIR spectroscopy,wideangle X-ray diffraction,and scanning electron microscopy.The miscibility and properties of the blends were characterized by ultraviolet-visible-spectroscopy and tensile testing.The blended sheets exhibited smooth surface when the content of silk fibroin was lower than 3 wt%.It suggests that silk fibroin molecules penetrate into the polyurethane and interrupt the intra-hydrogen bonding between the hard and soft segments.A homogeneous distribution of the silk fibroin aggregations in the WPU matrix was observed in the blends when the contents of silk fibroin were higher than 3 wt%.The results indicated that the blended sheets exhibited good miscibility,attributed to intermolecular hydrogen bonding between silk fibroin and polyurethane.The existence of polyurethane and relatively slow dryness process contributed to the crystallization of the silk fibroin.The tensile strength and Youngs modulus increased with an increase of silk fibroin content.The films having 5.6 wt% silk fibroin exhibited a significant increase from 0.56 MPa to 4.60 MPa for tensile strength and from 0.14 MPa to 1.71 MPa for Youngs modulus.They showed high elongation at break in the range from 1065% to 988%.
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发布时间：2021-03-19 - 摘要：A new method for synthesizing 3D skeletal polymers and coordinating polymer materials with controllable pore sizes is reported.The new method was based on a two-step phase separation,in the first step the curing reaction of epoxy resin in PEG medium was inhibited by using dodecylbenzenesulfonic acid to control the rate and extent of reaction induced phase separation; in the second step the obtained polymers in metastable state were treated with ZnSO4 or CdSO4 aqueous solutions to restart the phase separation and stabilize the 3D skeletal structures,under the effect of coordination the pore sizes could be adjusted in a range of 1～2 m.The light filtrating properties were studied through the filling of 3D continuous pores with divinyl benzene as a highly refractive liquid.The optical window appeared on the absorption spectra results from a total reflection of light in the 3D continuous liquid phase,which was verified by changing the refractive index of solid materials through the introduction of ZnSO4 and CdSO4 in polymer matrix.A qualitative relationship has been established between the wavelength range of transmitting light and the pore size with its distribution in a 3D skeleton.The above results presented a fundamental explaination of the new optical phenomenon.
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发布时间：2021-03-19 - 摘要：In order to explore the droplet formation process of the aqueous twophase polymerization of acrylamide (AM) in aqueous poly(ethylene glycol) (PEG) solution,dynamic light scattering (DLS) was employed to investigate the appearance,the size and size distribution of droplets in the initial stage of polymerization.The effects of PEG molecular weight and concentration on the droplets size and distribution were studied.It was found that the droplets stability in aqueous PEG solution decreased, and the droplets aggregated with each other to form larger and more uniform droplets with decreasing PEG molecular weight or PEG concentration.The morphology of the droplets rich in polyacrylamide (PAM) was observed with transmission electron microscopy (TEM).The droplets shape in the initial stage of polymerization is spherical but polydisperse.However,some oval droplets formed in the product,while the conversion was still very low，which indicated some coalescence of droplets in this stage.As the polymerization proceeds,the droplet size increased rapidly and the size distribution of droplets become uniform.These results were well in agreement with the DLS results.With using the spectrophotometer,the phase separation point was determined where the transparence of reaction solution declined suddenly.The effect of various parameters on the critical conversion of phase separation was measured by bromating method.It decreased with the increase of PEG molecular weight or PEG concentration.With raising temperature from 30℃ to 70℃,the critical conversion decreased at first,and then turned to increase when the temperature was at about 50℃.The critical molecular weight was also systemically investigated by gel permeation chromatogram (GPC).It could be seen that the evolution of critical molecular weight corresponded well with that of critical conversion at various reaction conditions.On the basis of above mentioned results,an initial droplet formation and growth mechanism of AM aqueous twophase polymerization in aqueous PEG solutions was proposed.As the reaction starts,primary radicals,generated by decomposition of the initiator,grow in the continuous phase by the addition of monomer units until they reach their critical chain length.Then these polymer radicals precipitate and aggregate to form nuclei.The nuclei are not stable,and they will immediately aggregate with each other to form tiny droplets.Then monomer and initiator diffuse into the droplets rapidly,and polymerization takes place in both the continuous phase and the dispersed phase (inside the droplets).In the earlier stage,the PAM droplets are stable and grow mainly by polymerization inside the droplet.Because new smaller droplets generate from continuous phase at the same time,the droplet size distribution becomes wide.However,these droplets become unstable with the polymerization and aggregate with each other to make the droplet size distribution become narrow again.
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发布时间：2021-03-19 - 摘要：A disubstituted acetylene with both polar and conjugate groups,phenylpropiolic acid (PhPA),was directly polymerized into poly(phenylpropiolic acid) oligomer through metathesis polymerization with Pd(PPh3)2Cl2 as catalyst and toluene as solvent,while the monomer PhPA was synthesized by the addition reaction of cinnamic acid with bromine and the followed elimination of hydrogen bromide.The polymerizations of PhPA showed a moderate yield of oligomer at 75℃ and in toluene solvent.The structures of both PhPA and oligomer were confirmed by IR and 1H-NMR.For example,the absorption band at 1620 cm-1 associating with CC stretching appears in the spectrum of oligomer,instead of 2210 cm-1 associating with CC stretching in the spectrum of PhPA.The oligomer is soluble in common polar solvents and has high thermal stability.Comparison of the absorption spectra of the oligomer with its monomer reveals that the absorption of the oligomer in the spectral region beyond 310 nm is associated with the electronic transitions of oligomer skeleton.On the fluorescence investigation of the oligomer,THF solutions of oligomer emit blue light and show the peak emissions at 420 nm at different concentrations when excited at 342 nm.At the concentration of 004 mmol/L of oligomer,its emission indicates the biggest intensity.
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发布时间：2021-03-19 - 摘要：The RAFT homopolymerization of St and copolymerization of St with Nsubstituted maleimides such as HPM,CPPM and BPPM, using AIBN as initiator,1-phenylethyl dithiobenzoate or cumyl dithiobenzoate as the chain transfer agent was investigated.The polymers were characterized by UV-Vis and GPC.The results suggested that both the homopolymerization and copolymerization exhibited a living behavior,and the molecular weight increased with the conversion and a narrow molecular weight distribution was achieved.For the homopolymerization,due to the unfavorable bimolecular termination of the PSt radicals,the capping efficiency of the PSt chains decreased gradually with the conversion.For the copolymerization,the charge transfer complex formation not only enhanced the reaction rate but also led to alternating sequence.The P(St-alt-BPPM) was also used as the macroinitiator for the ATRP of St to prepare comb-shaped PSt.The results implied that when NMP was used as solvent,the process proceeded in an uncontrolled fashion; on the other hand,when the reaction was carried out in St bulk,the comblike PSt had a much narrower MWD.
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发布时间：2021-03-19 - 摘要：The Block copolymer polystyrene-b-poly(acrylic acid)-bpolystyrene (PSt-b-PAA-b-PSt) was synthesized via reversible addition-fragmentation chain transfer polymerization by using styrene as the first monomer.The architectures of the macro-chain transfer agent PSt-CTA and the block copolymers were confirmed by FTIR and 1H-NMR.GPC analysis was used to estimate the molecular weight and the molecular weight distribution of the copolymers,the numeraverage molecular weight of macro-chain transfer agent PSt-CTA was 8320,and the molecular weight distribution was 1.05.The numer-average moleccular weight of three block copolymers was 13050,11130 and 9760,respectively,and the corresponding molecular weight distribution was 1.356,1.430,1.365.The block copolymers with different molecular weights were self-assembled by co-solvent method in an ionic liquid,1-butyl-3-methylimidazolium hexafluorophosphate (［BMIM］［PF6］).The nanostructures of the PSt-b-PAA-b-PSt micelles formed in the ionic liquid were observed by TEM (transmission electron microscopy) and DLS(dynamic light scattering).The self-assembled morphologies of the copolymers are strongly dependent on the length of PAA block chains when the chain length of PSt is fixed.With the decrease of molecular weight of PAA in block copolymers,the resulting aggregates are spheres with diameter of about 50 nm.With further decrease of PAA molecular weight in copolymers,the sphere morphology is turned to core-shell sphere micelles with diameters not more than 100 nm.Compared with the aqueous solutions of the same copolymers,［BMIM］［PF6］ solutions exhibit some distinct features,such as temperatureindependent micellar morphologies between 25℃ and 100℃.
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发布时间：2021-03-19 - 摘要：Poly(styrene-co-methacrylic acid) P(S-co-MAA) copolymer colloidal crystals were transformed to ordered porous arrays by selective dissolution using toluene as solvent.The atomic force microscopy (AFM) and scanning electron microscopy(SEM) were used to characterize the structure change during spherepore transforming process,and the AES was used to analyze the element content variety of the colloidal spheres before and after the conversion.The polystyrene core in the P(S-co-MAA) latex nanospheres first swelled,making the colloids conglutination.Then the bursting of the methacrylic acid shell led to it gradually dissolution,resulting in a porous structure.Owing to the liquidity of the macromolecule,the pores formed are irregular rounded.The surface element analysis indicates that when the polystyrenes in core are extracted from the colloidal spheres by solvent,they diffuse into the solvent,not fill in the interspaces among the spheres.In addition,the methacrylic acid riched on the colloidal surface has the function to fix and support the porous structure,but the structure could be ruined with long time immersion.
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发布时间：2021-03-19 - 摘要：The use of non-viral carrier,polyethyleneimine-g-methoxypoly(ethylene glycol) (PEI-g-MPEG) for interleukin-10 (IL-10) gene delivery into rat dorsal root ganglion cells (DRGs) was examined in vitro.Electrophoresis,ethidium bromide exclusion,SEM,size and zeta () potential measurements were performed to characterize the nanocomplex,PEI-g-MPEG/pDNA.In addition,the cytotoxicity,transfection efficiency and IL-10 protein expression level in comparison with lipofectamine as a delivery agent were determined.Results showed that plasmid DNA was completely complexed by PEI-g-MPEG at a nitrogen-to-phosphor (N/P) ratio of 5.The PEI-g-MPEG/pDNA complexes were well-distributed and spherical with smooth surface.As the proportion of PEI-g-MPEG increased,i.e.when N/P ratio increased from 1 to 30,the size of the PEI-g-MPEG/DNA complexes decreased from 229 nm to 130 nm,while the surface charge increased from -19 mV to 32 mV,which led to the increased cytotoxicity.Flow cytometry revealed that the highest transfection efficiency (24%) using PEI-g-MPEG as a delivery agent was obtained at N/P charge ratio of 15,which was higher than that of lipofectamine (17%) at the same N/P value.After transfection,rat IL-10 expression in DRGs primary culture assessed using ELISA was observed to localize in the cytoplasm at 48 h in concordance with the result obtained for EGFP expression.These results indicated that PEI-g-MPEG could be a potential candidate for gene delivery during the therapy of neuropathic pain.
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发布时间：2021-03-19 - 摘要：This paper demonstrates the successful synthesis of reactive isotacticpolypropylene terminated with styryl groups.The styryl group was introduced into the iPP chain end via chain transfer reaction to 1,4-divinylbenzene or 1,2-bis(4-vinylphenyl)ethane,during metallocenecatalyzed propylene polymerization by rac-Me2Si［2-Me-4-Ph(Ind)］2ZrCl2/MAO complex in the presence of hydrogen.Although hydrogen does not influence the polymer molecular weight,it greatly affects the catalyst activity.The iPP molecular weight is strongly dependent on the concentration of chain transfer agent.The isotacticity (mmmm) of iPP macromonomers is quite high ( 70%).The polymerization mechanism was also studied by using deuterium as labelled molecule of hydrogen in combination with 13C-NMR technique,and it is clear that the existent double enchainment of chain transfer agent is because the styryl-capped polymer chain would spontaneously insert into ZrH species with the unique 1,2-manner.The reactive iPP obtained was used as building block,and two kinds of topological structural polymers were synthesized.Styryl-capped iPP was copolymerized with styrene using CpTiCl3/MAO complex to produce sPS-g-iPP copolymer.Crude copolymer was subjected to extraction with chloroform which resulted in pure graft copolymer free of styryl-capped iPP.DSC results show thatTm,Xc,and Tc of sPS main chains and iPP side chains are all lower than those of the sPS and iPP homopolymers,separately.The appearance of extremely large supercoolings in sPS main chains is attributed to crystallization starting from homogeneous nuclei in isolated microdomains of graft copolymers which are generated by phase segregation.In addition,the terminal styryl groups of iPP were effectively transformed to azido groups through chlorination and substitutional reaction,and azidocapped iPP was obtained.Then,the click reaction between azido-capped iPP and trialkyne-containing couple agent was conducted in the presence of CuBr/PMDETA.1H-NMR results indicated that the click reaction was fast and highly efficient,and star isopolypropylene was synthesized.
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发布时间：2021-03-19 - 摘要：Tannic acid (TA) as a typical natural organic acid of high solubility and medium molecular weight,was used to study the adsorption act and mechanism on a new hyper-crosslinked resin modified by amino function groups WJN-08.The adsorption isotherm data indicates that the equllibrium adsorption capacity of WJN-08 for TA is 15% higher than that of other commercial adsorbents.Moreover,the static adsorption assay indicates that the adsorption capacity for TA is related to the pore structure and the amounts of amino function groups of resin.The FTIR spectra of WJN08 before and after adsorption of TA indicate that both - conjugation and electric attraction are the adsorption force during the adsorption process.The adsorption enthalpy changes H of TA by WJN-08 is in a range from 20 to 22 kJ mol-1,which exhibit the adsorption is a chemical and endothermic process.Batch kinetic studies indicate that the adsorption of TA on WJN-08 can be fitted by the membrane and intra-particle diffusion model.In particular,excellent adsorption and de-sorption performance of WJN-08 for TA is shown in dynamic column assay.The break though adsorption capacity is 19.56 mg g-1 and saturation adsorption capacity is 22.43 mg g-1,respectivey,and the desorption rate of TA on WJN-08 is more than 98%.
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发布时间：2021-03-19 - 摘要：Cyclohexene oxide copolymer (PCHC) with high molecular weight was synthesized using ternary rare earth metal coordinate catalyst (Y(Cl3COO)3ZnEt2 glycerine).The catalytic activity reached 11.8 kg polymer/mole Zn under optimal condition,the obtained PCHC showed number average molecular weight (Mn) of 7.0104, with carbonate unit over 95%.The glass transition temperature (Tg) of PCHC was between 110℃ and 120℃,it increased with increasing Mn when Mn was below 8.5104,and leveled between 119℃ and 120℃ when Mn was over 8.5104. The highest Tg may be reached as 120℃ if the Mn of PCHC is high enough,and the characteristic free volume constant K is 1.91105. The influence of molecular weight on thermal stability of PCHC was investigated,raising molecular weight was beneficial for improving thermal stability of PCHC,and a 60℃ increase of the onset degradation temperature was observed when Mn increased from 39.9103 to 93.1103. Since the rare earth ternary catalyst changed to metal oxide (mainly ZnO) after polymerization and post-polymerization treatments,the influence of Zn content on thermal stability of PCHC was studied based on Kissinger method,PCHC with Zn content below 510-6 showed surface activation energy for thermal decomposition of 199.9 kJ/mol,whereas it decreased to 143.9 kJ/mol for PCHC with Zn content of 440010-6.Therefore,reducing Zn content could improve the thermal stability of PCHC.
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发布时间：2021-03-19 - 摘要：The relationship between the evolution of morphology of concentrated immiscible polymer blends and their rheological properties during stress relaxation were investigated by morphological observation on a shearing device. It was discovered that the relaxation time of the droplets immersed in concentrated blend systems increased with the increase of concentration. The rheological properties of concentrated blends were investigated on a rotational rheometer. It was detected that the relaxation time of concentration blend systems was prolonged with the increase of concentration. The increase of the relaxation time of both the droplets and the blend systems with the increase of concentration are related directly to the hydrodynamic interactions among the droplets in concentrated blend systems. A constitutive model for concentrated polymer blend system is proposed on the base of MM model with the concept of effective medium. The environment around a droplet in concentrated blends is treated as an effective medium consisting of other droplets and the continuous phase. The viscosity of effective medium is not only a function of concentration, but also dependent on the morphology of droplet. The new suggested model can reasonably predict the evolution of the phase morphology and the stress relaxation behavior of the concentrated blend systems.
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发布时间：2021-03-19
Research Article
- 摘要：4,4-Bis(4-nitro-2-trifluoromethylphenoxy)diphenylether (p-6FNPE) was synthesized by the Williamson reaction between 4,4-dihydroxydiphenyl ether and 2-chlorine-5-nitro-trifluoromethyl benzene.Then,the reduction systems of Pd/C-hydrazine hydrate were adopted to obtain the corresponding products 4,4-bis(4-amino-2-trifluoromethylphenoxy)diphenylether (p6FAPE).Using three kinds of phenyl ether type trifluoromethyl-containing diamine,i.e., 1,4-bis(3-amino-5-trifluoromethylphenoxy)benzene (m6FAPB),1,4-bis(4-amino-2-trifluoromethyl phenoxy)benzene (p-6FAPB) and p6FAPE,and two kinds of dianhydride, i.e.,3,3,4,4-oxydiphthalic anhydride (ODPA) and pyromellitic dianhydride (PMDA),six kinds of fluorinecontaining polyimide (PI) films were prepared by the two-step method.The chemical structure and properties of the PI were characterized by FTIR,UVVis and TGA.The six kinds of fluorine-containing PI showed good solubility in aprotic polar organic solvents such as NMP,DMF and DMAc.PI obtained from mposition diamine showed better solubility.All the fluorine-containing PI films had good thermal stability,with a 5% weight loss temperature at 540℃ or higher.In the case of a same dianhydride,PI based on 6FAPE possessed higher thermal resistance than 6FAPB.Compared with PI based on PMDA,fluorine-containing PI films based on ODPA exhibited more excellent transparency in the visible wavelength range (400～700 nm),and their transmittance at 450 nm was over 80%.PI based on p-6FAPB exhibited better transparency than p-6FAPE.PI films obtained from m-6FAPB tended to be colorless and transparent.The PI synthesized in this work could be expected to be used in the applications such as solar cell substrate and waveguide board materials.
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发布时间：2021-03-19 - 摘要：The electrospray technique was used to prepare poly［(ethylglycino)(phenylalanine ethyl ester) phosphazene］ microparticles with very low polydispersity.By replacing the chloroform atoms of polydichloro\|phosphazene with alanine ethyl ester and glycine ethyl ester subsequently,poly［(ethylglycino)0.30(phenylalanine ethyl ester)0.70phosphazene］ (PGPP) was obtained and electrosprayed.The effects of processing parameters such as solvent,polymer concentration,liquid flow rate,applied voltage and receiving distance on the morphology and size of PGPP particles were investigated systematically.The morphologies of the electrosprayed PGPP microparticles were observed by scanning electron microscope (SEM),and the particle sizes were analyzed by using a software ImageJ basing on SEM photos.It was found that the morphology of PGPP microparitcles depended on polymeric concentration significantly.As PGPP concentration increased from 0.10 g/mL to 0.30 g/mL,rounder particles could be formed.The particles electrosprayed from PGPP solutions in tetrahydrofuran (THF) were less agglomerated than those obtained from the 1,4-dioxane solution,which was thought as a consequence of the faster de-solvent rate of THF.On the other hand,the parameters including the liquid flow rate,applied voltage and receiving distance mainly influenced the size of microparticle,among which,the effect of liquid flow rate on the particle size was most remarkably.The particle size increased with the increasing flow rate,generally obeying the Scaling law,while it decreased by increasing voltage or distance.Experimental data demonstrated that PGPP microparicles with nearly spherical morphology and a size of 1～2 m could be produced by electrospraying 0.25 g/mL PGPP/THF solution at the optimized parameters.In result,PGPP microparicles with controllable morphology and size could be obtained by changing the various processing parameters of electrospray,and this technique could be used to fabricate drugloaded polyphosphazene microparticles for further study on the drug controlled release behaviors,which might have potential applications in inhaled drug delivery systems.
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发布时间：2021-03-19
Research Bulletin
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