最新刊期
卷 ， 期 10 ， 2007
- 摘要：A thiol-functionalized poly(phenylacetylene) has been synthesized and characterized.The disappearance of the characteristic vibrations at 3312 and 776 cm-1(CCH)and 2106 cm-1 (CC),together with the vanishing of the chemical shifts at 3.0(CCH) and the appearance of the chemical shifts at 6.4 (CC—H) indicate the polymerization of the thiol-containing monomer.The hybrid of thiol-functionalized poly-(phenylacetylene) and multiwalled carbon nanotubes(MWNTs) showed good solubility in organic solvents.Meanwhile,the wrapping of the polymer chains on MWNTs led to the surface functionalization.By aid of the interactions between thiol groups and zinc cations,ZnO nanoparticles were assembled onto out-shells of the hybrids.These results suggested a novel route to the fabrication of multi-component nanostructures.关键词：Poly(phenylacetylene);Thiol;Carbon nanotubes;Solubility;Assembling
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发布时间：2021-08-24 - 摘要：Disubstituted polyacetylenes are fluorescent polymers,and they are more stable than their monosubstituted counterparts.In comparison with the reports about those monosubstituted polyacetylenes,there is only one example showing the dispersing effects of disubstituted polycetylenes on carbon nanotubes.In this letter we demonstrated the fabrication of the composites of multiwalled carbon nanotubes(MWNTs) and different disubstituted polyacetylenes,and the polymer chains wrapped onto the MWNTs via π-π interactions,leading to the improved solubility of MWNTs in organic solvents.This methodology is scatheless to MWNTs.Meanwhile,the disubstituted polyacetylenes encapsulating the MWNTs exhibited their unique photoluminescence properties.关键词：Disubstituted polyacetylenes;Wrapping;Carbon nanotubes;Solubility
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发布时间：2021-08-24
Rapid Communications
- 摘要：This feature article has summarized our research on layer-by-layer deposition films of polymers on the basis of hydrogen bonding,coordination bonding and covalent bonding.Moreover,our discussion has focused on unconventional methods of layer-by-layer deposition that invovles supramolecular assembly in solution and layer-by-layer deposition at solid/liquid interface.It has been demonstrated how to combine structural architectures with functional assembly leading to controlling the physicochemical properties of the surfaces,including biomineralization,superhydrophobic coating,controlled assembly and release,and surface molecular imprinting.It is anticipated that this line of research is of significance for developing surface molecular engineering of polymer multilayer films.关键词：Layer-by-layer assembly;Organized molecular films;Surface molecular engineering
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发布时间：2021-08-24 - 摘要：This review summarizes our achievements in controlling the chain structures of carbon dioxide-propylene oxide copolymers（PPC）.PPC with number average molecular weight（Mn） over 2×105 was obtained by double propagation mechanism,the resulted higher Mn copolymers showed improved thermal and mechanical performance than common copolymers with Mn lower than 1.5×105.Another way to regulate chain structures was employing crosslinking strategy.PPC bearing small moiety of pendant CC groups was synthesized by terpolymerization of allyl glycidyl ether,propylene oxide and carbon dioxide.Once subjected to UV radiation crosslinking,the dimension stability of the crosslinked copolymer was improved.The third way to regulate chian structures of PPC was controlling its region structure.Lewis base modification strategy on rare earth ternary catalyst was disclosed to enhance nucleophilic ability of active center,PPC with H-T linkages over 83% and Mn up to 1.0×105,was synthesized at room temperature using Y（CCl3OO）3-ZnEt2-glycerine catalyst and 1,10-Phenanthroline cocatalyst.When H-T linkages increased from 69.7% to 83.2%,a 8℃ increase of Tg was found,indicating that increase of H-T structure in PPC did raise its Tg.关键词：Carbon dioxide;Copolymerization;Chain structures;Molecular weight;Crosslinking;Region-regular structure
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发布时间：2021-08-24 - 摘要：Controlling the microstructure during polymer synthesis is an important goal in contemporary research on polymer chemistry;it is also a subject of advanced interdisciplinary studies of polymer science,supramolecular and material science.Ladder-like polymer has attracted much attention in recent years because it,in theory,has better resistance to all kinds of degradation than the conventional polymer with single-chain."Suprarmolecular architecture directed stepwise/coupling polymerization"(SCP),reviewed in this paper,is a polymerization method combining polymer chemistry with supramolecular chemistry.In SCP,supramolecular structure is formed at first by using weak interaction between molecules;then polymerization is conducted.Some ladder-like polymers with well-defined structure were synthesized by using SCP,including polysilsesquioxane with organo or oxygenic bridge and polyester.In other words,SCP realized the goal of controlling the microstructure with supramolecular weak interaction.In addition,this paper also discussed the applications of ladder polymers to advanced materials,such as the application in liquid crystals with ladder polymer backbone,tubular polymer based on ladder-like polymer used in entrapping the curing agent of epoxy,and quasisieve polymer which can be used in the preparation of NLO maerials.关键词：Supramolecular chemistry;Stepwise/coupling polymerization;Ladder-like polymer;Liquid crystal;Microstructure
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发布时间：2021-08-24 - 摘要：The research progresses in the dynamic rheological behavior of wheat proteins in solution,the equibiaxial extensional rheological behavior of plasticized wheat proteins as well as the preparation,structure and properties of wheat protein bioplastics were summarized mainly depending on the results obtained by the authors and their cooperators in Zhejiang University.The influences of pH and temperature on the rheological behavior of protein solution were investigated and the hybrid model was employed to understand the contributions of the rotational and the flexural modes of the molecular chain and the high-frequency viscous dissipation.The correction between deformation velocity,protein content,rest time and the equibiaxial extensional rheological behavior of plasticized proteins were probed in detail,and the mechanism of the formation of the three-dimensional fractal network was clarified.Moreover,wheat protein-based bioplastics were prepared using the thermo-molding method and the influences of molding parameters,crosslinking type and chemical modification on the structure and properties of the final product were discussed.It is believed that thorough understanding of the characteristic rheological behaviors for wheat proteins in solution or in plasticized compound may facilitate optimizing the processing technique as well as the morphology and the mechanical properties of protein bioplastics.关键词：Wheat protein;Degradable bioplastic;Rheological properties;Structure
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发布时间：2021-08-24
Feature Articles
- 摘要：Advance in solvents of cellulose was summarized in this article.N-Methylmorpholine-N-oxide（NMMO） could break the intermolecular hydrogen-bonds of cellulose at the temperature higher than 85℃,leading to the dissolution.Lithium chloride/N,N-dimethylacetamide（LiCl/DMAc） were able to dissolve cellulose at 100℃ or higher.Ionic liquids such as 1-allyl-3-methylimidazolium chloride and 1-butyl-3-methylimidazolium chloride could dissolve cellulose,as a result of the strong hydrogen-bond acceptor（Cl-）,which could associate with hydroxyl of cellulose.In carbamate system,cellulose derivate reacted with urea could be dissolved in NaOH aqueous solution.NaOH/H2O can only dissolve cellulose with low crystalline and degree of polymerization.Interestingly,cellulose could be dissolved rapidly in NaOH/urea,NaOH/thiourea and LiOH/urea aqueous systems pre-cooled to-5～-12℃.New hydrogen-bonded network structure between solvent and cellulose macromolecules could form to destroy the inter-and intramolecular hydrogen-bonds of cellulose.The inclusion complex hosted by urea or thiourea reduced the self-association of cellulose chains,leading to the good dispersion of cellulose.Low temperature dissolution is a great breakthrough to the traditional dissolving method,and also a strong driver force of the green chemistry.50 References were cited.关键词：Solvent of cellulose;Dissolution mechanism;Fiber;Hydrogen-bond
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发布时间：2021-08-24 - 摘要：This paper reviewed the concept of chaim entanglement and the methods to characterize entanglement.A new 1H-NMR strategy was developed to characterize the degree of chain interpenetration in glassy polymers chain,which indirectly offer the information of entanglement.This strategy was run in the isotopically enriched polymer blends using dipolar filter under fast magic angle spinning.By this strategy we found the original degree of interpenetration of polymer chains in solution could be partly retained by freeze drying.It was also found that in the PS cast film,even when the molecular weight of PS was much less than its critical entanglement molecular weight(M_c),the PS chains interpenetrated heavily,in which Van der Waals interaction played an important role.关键词：Entanglement;Interpenetration;1H-NMR;Fast Magic Angle Spinning;Dipolar Filter
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发布时间：2021-08-24
Reviews
- 摘要：A series of low band-gap conjugated copolymers（PFO-DDQ） derived from 9,9-dioctylfluorene（DOF） and 2,3-dimethyl-5,8-dithien-2-yl-quinoxalines（DDQ） is prepared by the palladium-catalyzed Suzuki coupling reaction with the molar feed ratio of DDQ around 1%,5%,15%,30% and 50%.The obtained polymers are readily soluble in common organic solvents.The solutions and the thin solid films of the copolymers absorb light from 300～590 nm with two absorbance peaks at around 380 nm and 490 nm.The PL emission consists exclusively of DDQ unit emission at around 591～643 nm depending on the DDQ content in solid film.The EL emission peaks are red-shifted from 580 nm for PFO-DDQ1 to 635 nm for PFO-DDQ50.Efficient energy transfer due to exciton trapping on narrow-band-gap DDQ sites has been observed.The highest external quantum efficiency achieved with the device configuration ITO/PEDOT/PVK/PFO-DDQ15/Ba/Al is 1.33% with luminous efficiency 1.54 cd/A.Bulk heterojunction photovoltaic cells fabricated from composite films of PFO-DDQ30 copolymer and -phenyl C61 butyric acid methyl ester（PCBM） as electron donor and electron acceptor,respectively in device configuration: ITO/PEDOT∶PSS/PFO-DDQ30∶PCBM/PFPNBr/Al shows power conversion efficiencies 1.18% with open-circuit voltage（Voc） of 0.90 V and short-circuit current density（Jsc） of 2.66 mA/cm2 under AM 1.5 solar simulator（100 mW/cm2）.The photocurrent response wavelengths of the PVCs based on PFO-DDQ30/PCBM blends covers 300～700 nm.This indicates that these kinds of low band-gap polymers are promising candidate for polymeric solar cells and red light-emitting diodes.
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发布时间：2021-08-24 - 摘要：For the purpose of manufacturing cigarette filter tows and filter rods,the melt-spinning,adhesion and adsorption properties of poly(lactic acid) were studied.The rheological measurements were performed to examine the effects of various processing conditions on the melt flowability and spinnability,including those of residual moisture.The melt spinning and post-processings were followed by determining the molecular weight,thermal and mechanical properties of the fibers.The results obtained were useful to establishing the specification of the PLA resins for filter tows and filter rods manufacturing and to choosing proper melt-spinning and post-processing technologies.关键词：Poly(lactic acid);Biodegradable;Cigarette filter;Melt spinning
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发布时间：2021-08-24 - 摘要：Two calixarene derivatives（2a,2b） have been synthesized and used as macro-initiators to prepare star-shaped poly（ε-caprolactone）s（SPCLs） via controlled ring-opening polymerization of ε-caprolactone in the presence of yttrium tris（2,6-di-tert-butyl-4-methylphenolate） [Y（DBMP）3].The molecular weight of SPCLs was characterized by end group 1H-NMR analyses and size-exclusion chromatography（SEC）.The results indicated that SPCLs based on calix[4]arene derivative（2a） are well-defined four-arm star polymers with narrow molecular weight distributions in a given molecular weight range,while SPCLs based on calix[6]arene derivative（2b） are star polymers not so defined.Differential scanning calorimetry（DSC） analyses suggested that the maximal melting point,the crystallization temperature,and the degree of crystallinity of SPCLs increase with the increasing of the molecular weight,and are lower than those of the liner poly（ε-caprolactone）（LPCL） counterpart.Furthermore,polarized optical microscopy（POM） indicated that SPCL exhibits irregular spherulites with poor morphology and apparently slower crystallization rate,whereas LPCL shows fast crystallization rate and good spherulitic morphology.关键词：Star polymers;Calixarene;Poly(ε-caprolactone);Rare earth catalyst;Ring-opening polymerization
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发布时间：2021-08-24 - 摘要：The H-shaped block copolymers（PTMSPMA）2PEG（PTMSPMA）2 with two compositions,（EG）91-b-（TMSPMA）92 and（EG）455-b-（TMSPMA）176 have been successively synthesized by atom transfer radical polymerization（ATRP）of tri（methoxylsilyl）propyl methacrylate（TMSPMA）at room temperature in methanol,and the initiation system applied in this system was composed of the 2,2′-（α-bromoisobutyryloxymethyl）propionyl terminated poly（ethylene glycol）（Br2PEGBr2）with Mn=4000 or 2×104,CuBr and 2,2′-bipyridine.The four functional macroinitiator,Br2PEGBr2 was prepared by reaction of two hydroxyl groups terminated PEG with 2,2′-（α-bromoisobutyryloxymethyl）propionyl chloride.The NMR spectroscopy and GPC measurements were used to characterize the structure and molecular weight and molecular weight distribution of the resultant copolymers.When the H-shaped block copolymers Sam 1 and Sam 2 were self-assembled in DMF and water solvents,and successively condensation reaction of trimethoxysilyl groups in PTMSPMA was carried out,stable large-compound vesicles with 10 nm diameter of pores were formed for Sam 1,but self-assembling of the Sam 2 in the selective solvents produced big vesicles aggregates.These two different morphologies of aggregates are attributed to their relative chain length of water soluble PEG.The vesicles formed from Sam1 with short PEG chains had big surface energy,which will lead them to self-assemble further,forming large-compound vesicles.关键词：Aggregates;Atom transfer radical polymerization;Macroinitiator;Vesicle;Selfassembly
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发布时间：2021-08-24 - 摘要：We synthesized multi-substituted monomer(GMA)_x-CD,containing β-CD and then produced lightly-crosslinked or highly branched hydrophilic polymer P(GMA)_x-CD by free radical polymerization.Meanwhile we produced hydrophobic linear PtBA-ADA.It was found that the two polymers formed micelles in basic water driven by inclusion complexation between β-CD and ADA.Depending on the initial concentrations of the polymers,the size of the micelles varied in the range from 150 nm to 300 nm.TEM and AFM observations show that the micelles processes core-shell structure with PtBA-ADA as the core and(GMA)_x-CD as the shell.Furthermore,the micellar structures could be fixed by chemical crosslinking of CD groups in the shell.关键词：Inclusion;Micelle;Core-shell structure;β-Cyclodextrin
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发布时间：2021-08-24 - 摘要：Reversible addition-fragmentation transfer(RAFT) polymerizations of acrylic acid were conducted using fractionated hyperbranched polyester(Bolton H20) based macroRAFT agent to obtain a hyperbranched multiarm copolymer of H20star-PAA.Phase transition and self-assembly behavior of H20-star-PAA at different solution pH were also studied by using dynamic light scattering(DLS) and transmission electron microscopy(TEM).The results show that at lower polymer concentrations,the hyperbranched macromolecules exist as unimolcular core-shell nanostructures with hydrophobic BoltornH20 as the core and swollen poly(acrylic acid)(PAA) as the shell,and the PAA shells will collapse on the surface of the micelles with decreasing the solution pH.While in high concentrations of the polymer,H20-star-PAA self-assemble into large multimolecular micelles due to the secondary aggregation of unimolecular micelles stabilized by the intermolecular hydrogen bonding.关键词：Reversible addition fragmentation chain transfer;Hyperbranched;Acrylic acid;Self-assembly
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发布时间：2021-08-24 - 摘要：Plastic foams based on plant oil resin were prepared via radical copolymerization of acrylated epoxidized soybean oil(AESO) and methyl methylacrylate(MMA).Effects of AESO/MMA ratio and dosages of initiator(BPO) and accelerant(N,N-dimethyl aniline) on compression performance of the plastic foams were carefully studied.It was found that the foam properties depended on the content of MMA and network structure of the cured resin.The foams synthesized with higher MMA content,or cured by higher BPO concentration or lower accelerant concentration exhibited higher compressive resistance.On the whole,the proposed technical route was able to generate foams with high AESO fraction,which helped to control cost and properties of the end-products.The resultant plastic foams possessed compression strength similar to that of conventional unsaturated polyester foams,but higher toughness.Moreover,the AESO/MMA plastic foams were proved to be biodegradable during soil burial.According to the above results,it is known that the present plastic foams made from renewable resources are capable for replacing conventional petrol-based foams in practical applications.关键词：Acrylated epoxidized soybean oil;Plastic foam;Compressive properties;Biodegradability
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发布时间：2021-08-24 - 摘要：Three chiral bulky vinyl monomers,(+)-4,4″-bis[(S)-2-methylbutoxy]-2′vinyl-para-terphenyl(p-BMVT),(+)-3,3″-bis[(S)-2-methylbutoxy]-2′-vinyl-para-terphenyl(m-BMVT) and(+)-2,2″-bis[(S)-2-methylbutoxy]-2′-vinylpara-terphenyl(oBMVT) were synthesized.The later two were new molecules.The dependence of polymerizabilities of monomers on the chemical structures and the dependence of chiroptical properties of polymers on the chemical structures and reaction conditions were systematically studied.p-BMVT and m-BMVT were readily polymerized by radical mechanism to produce optically active helical polymers.Moving the chiral alkoxy groups on terphenyl by just a distance of one bond length inversed the direction of optical rotation.o-BMVT was obtained with quite low yield and couldn’t undergo radical polymerization.Using polar aromatic solvent and apolar aliphatic solvent,increasing reaction temperature,and reducing monomer concentration favored the formation of polymers with higher specific optical rotation.
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发布时间：2021-08-24
Research Article
- 摘要：Wu-Plot can qualitatively describe relationship between the size of a polymeric microsphere and the weight ratio of the monomer to the stabilizer.In other words,for polymeric particles stabilized by surfactant,ionic groups or polymer chains,the average surface area(S) occupied per stabilizer is a constant.Previous experiments reveal that Wu-Plot can be well applied to the nano-sized polymer particles with different stabilizer.In the present work,using the latest experimental results,we demonstrate that Wu-plot can also be used for micron-sized polymeric microspheres.关键词：Polymeric sphere;Dispersion polymerization;Stabilizer
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发布时间：2021-08-24
Research Bulletin
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