最新刊期
卷 ， 期 6 ， 2005
- 摘要：Three hypercrosslinked polymeric adsorbents AH-1,AH-2 and AH-3 with different contents of tertiary antino groups were employed to remove resomlnol from aqueous solmions through static experiments A comparision of che thermodynamic behavior among the three aminated hypercrosslinked resins,the hypererosslinked resin NDA-100,and the macroporous weakly anton exchange resin D301 wag made．It was found that the aminated hypercrosslinked resins had the hishest adsorption capacities of resorcinol among the three types of polymers The results indicated that the efiective interactions causing different adsorption capacities of resorcinol on the three aminaled hypercrossllnked polymefic adsorbents were mainly the Van der Waals force and the hydrogen-bonding interaction The adsorptions of resorcinol on the hypererosslinked resins were all spontaneous exothermic processes of physical characters．A first-order irreversible reaction rate equation was suitable to the adsorption process and the adsorption rate constants decreasing with increasing the content of tertiary amino groups in the resins．
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发布时间：2021-03-19 - 摘要：Nanocomposites of fluorinated polyimides (FPI) with covalently grafted polymethacrylate side chains containing polyhedral digomerie silsesquioxane (R7R'Si8O12 or POSS) units were prepared by thermally-initiated free-radical grit polymerization of methacrylcyclopentyl-POSS(MA-POSS) with the ozone-pretreated FPI．The chemical composition and structure of the FPI with grafted methaeryleyclopentyl-POSS side chains were characterized by nuclear magnetic resonance(1H-NMR) and X-ray diffraction (XRD)．The morphology of the POSS/FPI nanocomposite films was observed by field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM)．A layer-by-layer structure was revealed,which supports the formation of an ordered architecture by POSS crystallites in the FPI matrix,as the result of self-assembled POSS units of MA-POSS side chins The POSS/FPI nanocomposite films had both lower and tunable dielectric constants,in comparison with that of the pristine FPI films．Dielectric constants(k’s) of about 2.5 to 2.1 were obtained．The reduction of dielectric constant was most likely due to a combined contribution of the nanoporosity of the POSS units and the extemal porosity introduced by the grafting of MA-POSS to the FPI chains．
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发布时间：2021-03-19 - 摘要：Crosslinked cole-shell poly(butyl acrylate)/polystyrene(PBA/PS) and poly(butyl acrylate)/poly- (methyl methaerylate) (PBA/PMMA) nanopartieles were preparation via seeded emulsion polymerization．High crosslinked structure formed in both the core and the shell due to using crosslinking agent．which prevenled the migration of hydrophobic PS shell to the inside of particles There were covalent bonds on the interfaces between the cores and the shells in both panicles．The average particle sizes were 40～50 nm,and the size distributions were narrow．The kinetics was investigated．Well-defined core-shell structure and narrow particle sige distribution could be achieved under starved conditios of monomer Ⅱ feeding．Furthermore,PBA/PMMA partieles were filled in nvlon 6 matrix and increased the tensile modulus and impact strength by 38％ and 31％．respectivelv．
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发布时间：2021-03-19 - 摘要：The cationic sudactant trimerhyloctadecylammonium chloride (OTAC) and the reactive cationic surfactant allyldimethyloctadecylammonium chloride (ADAC) were used for the intercalation of MMT．PS/C18MMT and PS/AC18 MMT nanocomposites were synthesized by in situ emulsion polymerization The results of XRD and TEM showed that MMT was exfoliated into sheets of individual layers or few layers during polymerization and randomiy dispersed in the PS matrix．TGA curves indicated that the degradation temperature of the nanocomposites was enhanced by the addition of MMT,moreover,the degradation temperature of PS/AC18 MMT was higher than that of PS/C18MMT due to the existence of chemical links between PS and the layers of organ-MMT．The results of dynamic mechanical analysis showed that the storage modulus G’and loss factor tanδ of PS were increased and decreased respectively with the addition of MMT．The glass transition temperature of PS/AC18 MMT is higher than that of the pure PS while the glass transition temporature of PS/C18 MMT is slightly lower than that of the pure PS．
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发布时间：2021-03-19 - 摘要：Urushiol-titanium polymer(PUTi)/organomontmorillonite (OMMT) hybridnanocomposites were prepared via a solution-intercalation process The structure and pmperties of PUTi/OMMT were characterized by X-ray diffraction (XRD),transmission electron microscopy (TEM) and thermogravlmotry (TG)．The results of XRD showed that the crystalline spacing in OMMT was increased．indicating the intercalation of PUTi chains in OMMT crystallites．The (001) diffraction peak was not observed in the hybrid nanocompesites while the amount of OMMT was not more than 3.0 wt％．TEM studies indicated that the OMMT was distributed in the PUTi/OMMT nanocomposites at the nanometer level．The PUTi/OMMT nanocomposites have better thermal stability and ultraviolet resistance than PUTi.
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发布时间：2021-03-19 - 摘要：Plasticized monofilament absorbable sutures were prepared with poly(p-dioxanone) and poly(p-dioxanone-co-glycolide)．The poly(p-dioxanone) sutures (PDS) with different contents of plasticizer and poly(p-dioxanone-co-glycolide) sutures (PDG) treated under different conditions were analyzed by DSC．The effect of heat treatment temperature on the origin tensile strength,modulus and flexibility were studied,and the degradation properties and strength properties of the two kinds of sutures in vitro hydrolysis were also investigated The results showed that the glass transition temperature (Tg),crystallization temperature(Tc) and melting point (Tm) of PDS were all lowered with the introduction of plasticizer,while the ability of crystallizatlon was improved、The origin tensile strength and melting heat of PDG were increased withr aising the heat treatment temperature It was found that the retention of tensile strength of PDS and PDG increased first and then decreased with the increase of plasticizer content．while the percentage of weight retention decreased all long in vitro hydrolysis.
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发布时间：2021-03-19 - 摘要：By using spectroscopic variation of azo chromophores in different states as a‘probe’,chmmophore H- aggregation kinetics of a branched side-chain azo polyelectrolyte PMAPB6 P-AA in THF/H2O solutions was studied．The THF/H2O ratio showed a significant effect on the H-aggregation rate．The H-aggregation rate increased as the H2O content increased It indicates that the hydrophobic effect is an important dfiven force in the process of H-aggregation．The kinetic process of the H-aggregation was characterized by the change of the UV-Vis absorption ratios of the‘isolated’ azo chromophores and H-aggregates．Two kinds of kinetic equations were used to fit the H- aggregation process The process can be well fitted by the second-order kinetic equation．
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发布时间：2021-03-19 - 摘要：The photochemical behavior of a photochromic liquid crystalline (LC) dendfimer of the second generation (G2) in chloroform and tetrabydrofuran was described．Thirty-six 4-n-hexyloxyazobenzene mesogenic fragments were attached in its periphery．The photochemical behavior of carhosilane dendrimer of the second generation (G2) was compared with that ofthe carbosilane dendrimer of the first generation (G1) and the mesogenic unit compound (M3). The quantum yield Ф and intensity of light absorption Ia of G2,G1 and M3 were determined． In chloroform and tetrabydrofuran (THF) Ф was in an order of M3>G1>G2,while,Is in chloroform and tetrabydrofuran (THF) had orders of G2>G1>M3 and M3>G1>G2,respectively．The reaction rate constant of the thermal back-isomerization kH at different temperature and the activation energy E of G2,G1and M3 were discussed．At the salnetemperature,kH in chlomfoform and tetrahydrofuran (THF) wasin an order of G1>G2>M3． The photoisomerization conversion percentage and trans/cis isomer absorbance ratio at the thermal back-isomerization of G2．G1 and M3 were described．The photoisomerization conversion percent were in chloroform and tetrahydrofuran (THF) showed orders of G1>M3>G2 and G2>G1>M3,respeetively．The trans/cis isomer absorbance ratio at the thermal back-isomerization A'／A'o in chloroform and tetrahydrofuran (THF) was in order of C2>G1>M3．
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发布时间：2021-03-19 - 摘要：The pseudo-ternary phase diagram of the emulsifier mixture of Span20 and Tween80,acrylamide(AM), 2-(methaeryloyloxy)-ethyhfimethyl-ammoniumchloride (MADQUAT),sodium-2-aerylamido-2-methyl-propane-sulf-onate (NaAMPS) and eyclohexane was drew by a lot of experiments The kinetics for the inverse microemulsion polymerization of acrylamide,cationic monomer and anionic monomer were carried out by using (NH4)2S2O8-NaHSO3 as redox initiator．The apparent activation energy of the polymerization was calculated by Arrhenius equation to be 68.10 kJ/mol,and the effects of monomer concentration,inifiator concentmtion and emulsifier concentration on polymerization rate and intrinsic viscosity of polymer were determined．The kinetics equations of Rp and [η] could be expressed as Rp ∝[M]1.74[APS]0.60[E]-1.28,and [η] ∝[M]0.78[APS]-0.23[E]-0.71 respectively．The mechanism of the inverse mieroemulsion polymerization was also discussed．
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发布时间：2021-03-19 - 摘要：The polycarbosilane (PCS) precursor for SiC fibers was synthesized in an autoclave from poly djmethylsilane (PDMS)．The influence of reaction temperature on the Si—H bond content,degree of branching,Si-Si bond content,molecular weight and distribution,softening point and yield of the PCS was investigated．The results showed that,with raising the reaction temperature the weight average molecular weight,degree of branching and softening point increased,the molecular weight distribution broadened and the Si—Sj bond content decreased．The Si一H bond content and PCS yield increased with temperature in the range below 460℃ and decreased over 460℃ The conversion process included initially the formation of PCS by thermal decomposition of PDMS and then the increase in molecular weight by condensation among the PCS molecules．An medium molecular weight peak appeared while the reaction temperature was over 450℃,and the PCS was stable with low Si—Si bond contents in air at room ternperature.
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发布时间：2021-03-19 - 摘要：Narrow size distributed soap-free P(MMA-EA-MAA) latex particles with different crosslinking degree were synthesized by seeded emulsion polymerization of methyl methacrylate (MMA),ethyl acrylate (EA) and methacrylic acid (MAA),and voids and muhihollow latex particles were obtained after undergoing alkali treatment．Influences of kind and amount of crosslinking agents on the polymerization,particle properties and particle morphology were investigated．Results showed that the monomer conversion increased slightly in the presence of the crosslinking agents The size of particles decreased slowh as the amount of cmsslinking agent increased．and the size distribution of the particles broadened at a higher amount of cmsslinking agent Divinyl benzene (DVB) was more effective than ethyl glycol dimethyl methacrylate (EGDMA) to make polymer crosslinked．During alkali treatment process,void latex particles can be obtained when no DVB or less than 0.5 wt％ of EGDMA was used,while muhihollow structure was generated when DVB or more than 1.0 wt％ of EGDMA was introduced．The volume expansion of the particles decreased with increasing the amount of emsslinkirlg agents．
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发布时间：2021-03-19 - 摘要：The composites of thermoplastic starch plasticized by urea and formamide/citric acid-activated montmorillonite (UFTPS/CMMT) were prepared by the method of melt-interealation The ratio of urea and formamide used was 2：1 Wide angle X-ray diffraction (WAXD),transmission electron microscope (TEM) studies revealed that UFTPS was intercalated into the layers of CMMT successfully and formed composites with CMMT．When the CMMT content was 2 wt％～10 wt％．after the composites had been stored at a reletive humidity of 50％ for 10 days,the mechanical testing indicated that the maximum tensile strength of the composites reached 24.86 MPa,and the tensile strain reached 134.50％．Youngs modulus increased from 87.25 MPa for pure UFTPS to 625.25 MPa for UFTPS/CMMT composites．and the breaking energy increased from 1.87 N·m to 2.45 N·m,which showed that mechanical properties of composites were evidently better than those of UFTPS. Rheology analysis illustrated that during the process of composite preparation both the extruder screw speed and the processing temperature could effectively aajust the flow behavior of composites．Comparing with traditional GTPS,the composites greatly reduced the recrystallization resulting from long time storing．In contrast to pure UFTPS．the composites had better water resistance and thermal stability.
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发布时间：2021-03-19 - 摘要：Five series of polymeric hydmgds based on 2-hydroxyethyl methacrylate (HEMA) of 90 wt％ and a macromolecuiar cmsslinker— E-51 dimethacrylate (E-51-DMA) of 10 wt％ were prepared by bulk copolymerization,crosslinked with N, N'-methylene-bisacrylamide (MBA),divinyl benzene (DVB),ethylene dimethacrylate (EDMA),1,1,1-triacryloxymethyl propane (TAP) and 2,2,2-triaeryloxymethyl ethanol (TAE),respectively The effect of the species and content of erosslinkers on swelling properties,Young’s modulus,effective crosslinking density(ve) and polymer-water interaction parameter(χ) were studied,and cmsslinking efficiencies of various crosslinkers were also compared．As the amounts of cmsslinkers increased,a large number of emsslinks will be generated wihtin hydmgels,so the equilibrium water content (EWC) decreased,in contrast,the volume fraction of polymer in hydrogels (φ2) increased．As a result,the enhancement of effective crosslink density (ve) concerning network structures and interaction parameter(χ) that represents thermodynamic interaction between water and polymers could be observed．The erosslinking efficiencies of five adoptive cmsslinkers in E-51-DMA10/HEMA90 hydmgel systems were fitted from the relationships between effective crosslink density and theoretical crosslink density．and their order was as follows DVB>EDMA>TAE>MBA≈TAP The changing magnitudes for these above-mentioned parameters may be attributed to the nature of crosslinkers and their emsslinking efficiencies．
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发布时间：2021-03-19 - 摘要：The influence of PAAC template on the structure of resulting copolymers from the acrylamide (AM)/ acrylic acide (AA)/polyallylammonium chloride (PAAC) template copolymerization aqueous system was studied by IR．1H-NMR and 13C-NMR．It was found that the template of thistype had a great effect onthe sequence distribution and molecular weight of copolymer P(AM/AA)．As the pre-assembly of AA monomers onto the PAAC template,copolymers from the template system exhibited significantly longer AA and AM sequences compared with those of copolymers from non-template systems This block-like structure was further verified by dissociation constant (pK'a) measurements．In addition the iniluence of PAAC molecular weight．molar ratio of template to monomer AA and molar ratio of AM to AA was also studied．It should be noted that the copolymer product after separation contained a small amount of bended template.
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发布时间：2021-03-19 - 摘要：The present work was focused on investigating the potential of using side chain liquid crystalline Polymers (SCLCP) as nucleating agents for semicrystanine Polymem For this purpose,two vinyl monomers with liquid crystalline properties were designed and prepared．By means of homopolymefization two side chain liquid crystalline polymers having different architectures were synthesized．The monomers and the Polymers obtained were characterized by elemental analysis．FTIR and 1H-NMR measurements．DSC and HS-POM were employed to study the phase-transition tempemtums and mesophase textures for the polymem．The thermal stability of the polymem was measured by TGA．The results showed that the polymem were all thermotropic side chain liquid crystalline polymem with wide liquid crystalline phase temperature range and excellent thermal stability．The effect of one of the SCLCPs used as a nucleating agent in the crystallization of high density Polyethylene (HDPE) was investigated by DSC and HS-POM．The results indicated that SCLCP could effectively increase the crystallization temperature,crystallization speed and the crystallinity for HDPE．It was found that the synthesized SCLCP could be an effective nucleating agent for HDPE.
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发布时间：2021-03-19 - 摘要：The isothermal crystallization kinetics for four impact propylene eopolymers with different ethylene contents at different crystallization temperatures were investigated by employing differential scanning calorimetry (DSC)．The results indicated that the kinetics of isothermal crystallization for all the samples was fitted quite well by the Avrami equation within the selected crystallization temperature range(126～130℃)．With the increase of ethylene content in impact propylene copolymers,the Avrami exponent (n) did not vary significantly with temperature．The crystallization of impact pmpylene copolymer may involve heterogeneous nucleation with the controlled 3-dimensional diffusion Crystallization activation energy (△E) of four impact propylene copolymers ranged from about 279.5 to around 343.1 kJ/mol As the ethylene content increased,the crystallization activation energy increased The results clearly indicate the significant influence of the ethylene content on the crystallization activation energy．The results of CRYSTAF test showed,along with the increment of the ethylene content,an increase in the tacticity of propylene homopolymers and decreases in the isotacticity、long crystallizable sequence content.
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发布时间：2021-03-19 - 摘要：The influence of vaper-grown carbon fibers (VGCFs) as a filler on the isothermal cure reaction of tetraglycidyl-4,4'-diaminodiphenylmethane (TGDDM)/4,4’-diaminodiphenylsulphone (DDS) epoxy was studied using differential scanning calorimetry (DSC)．When VGCFs were incorporated into the TGDDM/DDS system,the activation energy of the composites decreased The cure reactions of VGCF composites showed an autocatalytic behavior as well as the pure TGDDM,DDS epoxy．DSC experimental results showed that VGCF had very small effect on cure kinetics of the TGDDM/DDS system A modified autocatalytie model was used to describe the cure reaction．Good agreement between data of the nlodified autocatalytic model and the experimental ones was found over the whole curing temperature range for both neat TGDDM/DDS epoxy and its VGCF composites．
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发布时间：2021-03-19 - 摘要：A series of novel cellulose resins grafted with calix [4] arene 4a～4c were obtained by reactions of eellulose poly (ethyleneimine) derivatives 2a～2c with 1,3-bis-epoxypropyl Calix [4] arene 3．The structure and appearance of the chelming resins were characterized by IR,element analyses and SEM images．The degree of substitution of calixarene in 4a～4c was 0.75,0.82 and 0.87,respectively．The adsorption experiments of 4a～4c towards a series of cations showed that the calixarene units played an important role in adsorption．These resins combined the adsorption advantages of cellulose derivatives and calixarene polymers,exhibited not only high adsorption capacities．but also high adsorption selectivity．Chelating resins 4b and 4c showed very high adsorption selectivitv towards Ni2+．The saturated adsorption capabilities of 4a～4c were as high as 2.96,2.93 and 2 66mmol/g,respectively．The adsorption capacities of 4a～4c decreased remarkably when pH<4,andthey can be reused by desorption with aqueous solutions of 10％ ammonium hydroxde.
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发布时间：2021-03-19 - 摘要：MgCl2-supposed Ziegler-Natta (Z-N) catalysts containing three different Lewis bases (diisobutyl phthalate,9,9-bis (methoxymethyl) fluorine and 1,1-bis (methoxymethyl) cyclobutane) as intemal donors were prepared for pmpylene polymerization．The relationship between the structure of donors and the performance of catalysts were investigated The Z-N catalyst contmning 9,9-bis(methoxymethyl) fluorine as intemal donor and the related compounds were characterized by FTIR spectroscopy．It was found that the intemal donor in the MgCl2/TiCl4/ Donor catalvst svstem was directly coordinated to MgCl2．The introduction of intemal donors decreased the Ti content in the catalyst system．increased the catalytic activity and narrowed the molecular Hlass distribution of polymers obtained The stereospeciflcity of Z-N catalysts gready depended on the structure of electron donors．A model of muhi-active sites on heterogeneous Z-N catalyst was proposed to explain the experimental resuhs．
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发布时间：2021-03-19 - 摘要：The transesterification in polycarbonate/poly(ethylene-co-acrylic acid)(PC/EAA) melting blend system with the presence of dibutyltin oxide (DBTO) catalyst was investigated during compounding by means of a Haake torque rheometer．The characteristics of the products were evaluated by Soxhlet extraetion and DSC．1H-NMR analyses．The results showed that the transesterification reaction did take place in the PC/EAA blend svstem．grafted or co-crosslinked copolymers PC,EAA were in situ generated at the interface of the blends during processing；the extent of exchange reaction,the structure and stability of reaction products depended upon the mixing time and the content of the catalyst．With mole catalyst and reaction time,more co-crosslinked copolymers were obtained.
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发布时间：2021-03-19 - 摘要：The precursor polymer PI-OH was pmpared by the polycondension of bisphenol-A diamine monomer (BISDA) and a dianhydfide monomer (6FDA) in solution Then cinnamoyl chloride was reacted with the hydroxyl-containing precursor to prepare the photosensitive polymer PI-CI with einnamate pendant groups The polymers were characterized by FTIR,1H-NMR and differential scanning calorimetry (DSC) The photochemical properties of PI-CI were studied by using UV-Vis and FTIR The polymer showed significant photodichmism upon UV irradiation due to the photodimefization After processed by Linear Polarized Polymerization (LPP),the spin-coated fihns of PI-CI wee used as photo-alignment layers to assemble sandwich-type liquid crystal cells via a capillary action using a nematie liquid crystal 5CB The observation by polarized microscope showed that the PI-CI photo-alignment layem had the ability to align LC molecules in a very uniform way．The photosensitive polymer PI-CI of bisphenol-A is promising for the application as photo-alignment layer for liquid crystal displays.
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发布时间：2021-03-19 - 摘要：An altered-temperature inverse suspension polymerization,which was suitable for negatively thermosensitive macromers,was presented to prepare thermosensitive and biodegradable microgels．The thermosensitivity and biodegradability of microgels come from those of rnacromers．The microgels were synthesized in suspension,in which the continuous phase was heptane Ammonium persulphate and N,N,N’,N’-tetramethylethylenediamine were employed as the initiating system．The negatively thermosensitive maeromer aqueous solution was first dispersed well at low temperatures(lower than the sol-gel transition temperature of the macmmer solution) and then crosslinked after raising temperature．The highlight of this approach is the avoidance of dispersion difficulty of the dispersion phase because of its physical gelation at polymerizing temperature．The thermosensitivity and biodegradation of the resulting micmgels were confirmed The volume phase transition temperature of mierogels was around 25℃．and the volume of microgels at 37℃ was less than half of that at 4℃ Mierogels were completely degraded into water-soluble products．It was necessary to add aqueous solutions of initiator and accelerator into the continuous phase after raising temperature．The ratio of oil to water influenced the morphology of miemgels to a certain degree．
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发布时间：2021-03-19
Research Article
- 摘要：Polymerlzation of N-Octadecylmaleimide was studied using rare earth coordination catalysts in toluene．The dependence of polymerization on molar ratio of catalyst components,different rare earth elements,catalyst coneentration,monomer concentration,polymerization time and polymerization temperature was investigated in detail The resuIts showed that the yale earth catalysts were favorable catalysts for the polymerization of N-Octadecylmaleimide A suilable condition for the polymerization was [La(P507)3]= 1×10-2 mol·L-1； [Al(i-Bu)3]=8.0×10-2 mol·L-1 NODMI]=5.0×10-1 mol·L-1；60℃；6h. Characterization of the polymer obtained showed that polymerization of N-Octadecylmaleimide proceeded via opening the double bond in the monomer molecules．The heat-resistant property of the polymer was investigated primarily．The polymer showed excellent thermal stability The thermal decomposition of the polymer proceeded via a one-step reaction and no substantial weight loss was observed below 350℃．The initial decomposition temporature(Tini)was 360℃,the maximum decomposition emperature(Tmax) was 441℃,and the residual weight at 500％ was about 3.4 wt％．
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发布时间：2021-03-19 - 摘要：Serf-association behavior of an amphiphilic polypeptide graft eopolymer,poly(γ-benzyl L-glutamate)-g-poly(ethylene glycol),and the drug carrier capability of the formed mieelles were examined by fluorescence spectroscopy．transmission electron microscopy and UV spectroscopy．It was found that the hydrophabie inner core of the micelles formed by poly(γ-benzyl L-glutamate) (PBLG) segments can act as an incorporation site for hydrophobic drugs．The drug-loading content of the graft copolymer mieelles tends to be larger when the content of the PBLG segments in the copolymer increases．The results obtained from the drug-release studies showed that the drug-release rates were dependent on the chemical nature of the graft eopelymer．
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发布时间：2021-03-19 - 摘要：Tremolite as a filling material influences the properties of epoxy matrix Before making composites,the tremolite was treated with cetyl trimethyl ammonium bromide The composite was first prepared with organic tremolite．epoxy CYD-128 and curing agents The changes of surface properties of organic tremolite were investigated using FT-IR．The impact strength．bend strength and bend modulus of tremolite/epoxy composites were studied with the tremolite content varied from 1％ to 8％ by mass The fracture morphology of the impact specimens was observed by scanning electron microscope (SEM),and the tremolite dispersion was observed with tunnel electron microscope (TFM)．The investigation of the thermo-mechanical behavior was performed by dynamic-mechanic thermal analysis (DMA)．As a result,when tremolite was installed,the bend strength increased by 100％ up to 118 MPa compared with the neat epoxy．The bend modulus increased from 3100 GPa to 4100 GPa The impact strength increased by 200％ up to 13 kJ/m2 compared with the neat epoxy Significant improvements in the mechanical properties of the resulting composites were illustrated in the storage modulus．From the surface analysis,it was found that surface was organic Tremolite was dispersed well in epoxy matrix as fiber state,so it enhances the mechanical properties of epoxy matrix.
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发布时间：2021-03-19 - 摘要：The nano-sized antimony trioxides (NSb2O3) were modified by in situ polymerization of styrene(St) and in situ copolymerization of vinyl silane (VS) and St,respectively,and then compounded with high impact polystyrene (HIPS) in molten state．The results showed that the surface of NSb2O3 was coated with polystyrene,subsequently the dispersion of NSb2O3 in HIPS matrix is remarkably enhanced Thereby,the tensile and impact properties of HIPS/Sb2O3 nanocomposites are improved,and there is a critical PS-coating thickness on the surface of NSb2O3 Because the in situ copolymerization of NSb2O3/VS/St is useful for PS to be grafted on the surfaces of NSb2O3,as a result of the enhanced interracial adhesion between NSb2O3 and HIPS matrix the Young’s modulus,tensile yielding strength and impact strength of HIPS/NSb2O3 nanocomposites are higher than those in HIPS/NSb2O3 nanocomposites modified by the in situ polymerization of NSb2O3/St.
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发布时间：2021-03-19 - 摘要：Poly3-[4-(4-pentyl-cyclohexyl)-phenyl]-thiophene(P3PhChPeT) films have been electrochemically synthesized by direct oxidation of 3PhChPeT in the mixed electrolyte of boron thrifluoride diethyl etherate(BFEE) and ethyl ether(EE) (4：1,by volume)．The oxidation potential of the monomer was measured to be 1．1 V (veisus Ag/AgCl)．P3PhChPeT in dedoped state is soluble in usual organic solvents such as tetrahydrofuran and chloroform, etc The structure of the polymer films was studied by infrared,Raman and UV-visible spectroscopies．The molar mass of the polymer was measured to be about 3400 g/mol with polydispersity of 1.23．The fluorescent spectra showed a single broad band at 565 nm with excitation at 450 nm．The thermal analysis result indicated that this polymer had a high thermal stability with a decomposition temperature higher than 500℃．
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发布时间：2021-03-19 - 摘要：Two UV curable hyperbrancbend polysiloxanes(I and Ⅲ) containing vinyl and allyl end groups and an UV cationic curable hyperbranehed polymer Ⅱ-Ep with epoxy end groups,were synthesized via the polyhydrosilylation using AB2 type monomers．All hydrosilylation reactions were catalyzed by Pt/C or chlomplatinic acid．Three AB2 type monomers were synthesized via hydrolyzation of functional ehlorosilane prepared by using Grignardeagents．and diehlorosilane．Themolecular structuresofthepolymers were characterized by 1H-,29Si-NMR,FTIR and GPC．and the UV-curing behaviors of polymers in different atmospheres and different photoaeeeleratots were also investigated.
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发布时间：2021-03-19
Research Bulletin
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