最新刊期
卷 ， 期 3 ， 2016
- 摘要：Polymer composite systems,also termed as polymeric alloys,can provide a highly cost-effective way of creating novel materials with either characteristics of all the constituents or new desirable properties. The study of these systems is significant in polymer physics,polymer chemistry,material science and modern industrial applications,which leads to the result that multicomponent polymeric materials become the cutting edge of interdisciplinary scientific research. Due to their relatively simple structural features,homopolymer/diblock copolymer/homopolymer ternary materials provide a model system for studying some long-standing fundamental issues in polymer science and have potential engineering and functional applications. In recent years,this model system has been the subjects of extensive theoretical,experimental and simulation studies,and many important progresses have been achieved.However,related reviews about this field are still scarce.In this review article,we comprehensively describe the basic concepts and the development history in the field of polymer composite systems and highlight the effects of diblock copolymer compatibilizers on phase behaviors and interfacial properties of the ternary blends. In particular,the critical issues,development prospects,and research directions in this field are introduced as well.关键词：Block copolymer;Compatibilizer;Polymer composite system;Phase behaviors;Interfacial tension
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发布时间：2021-03-19
Reviews
- 摘要：Alkynyl-capped PNIPAM with low molecular weight (Mn=9800) and narrow distribution was prepared through ATRP to investigate the effect of alkynyl groups on the phase transition of PNIPAM in aqueous solutions with high sensitivity differential scanning micro-calorimetry (micro-DSC),in the viewpoints of thermal capacity (Cp),phase transition temperature (PTT) and enthalpy change (H) upon heating and cooling.Being different from PNIPAM with high molecular weight,this alkynyl-capped PNIPAM shows that with heating-cooling cycle of micro-DSC measurement,the thermal capacity diagramss upon heating become significantly wider while those upon cooling change gradually from the bimodal curves to the unimodal curves.As well,PTT upon both heating and cooling is decreased and H is hardly changed with heating-cooling cylces.The results suggest that the alkynyl end-groups would play an important role in influencing the phase transition of PNIPAM.Probably due to hydrophobic or - interactions,the alkynyl end-groups might induce the assembly of some PNIPAM chains to form small aggregates.The PNIPAM chains in those small aggregates are more convenient to collapse simultaneously upon heating and more difficult to stretch upon cooling due to chain relaxation until the small aggregates and free chains of PNIPAM reach the dynamic equilibrium,resulting in the gradual decrease of PPT.关键词：Poly(N-isopropylacrylamide);Phase transition;Differential scanning micro-calorimetry;Molecular weight;Alkynyl end-group
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发布时间：2021-03-19 - 摘要：The original solution of polybutadiene (PBD) rubber from industrial plant was directly used as a starting material to synthesize hydroxyl-terminated polybutadiene (HTPB) with high cis-1,4 content and extremely low glass transition temperature for the first time.The synthetic process was divided into two parts,including the oxidolysis for the preparation of aldehyde group-terminated polybutadiene (ATPB) and the subsequent reduction reaction from ATPB to HTPB by NaBH4.The microstructure of PBD rubber nearly kept unchanged during the whole process so that the resulting HTPB retained a high cis-1,4 content ( 95%).The molecular weight was manipulated in the range of 2200~7000 (determined by 1H-NMR) by controlling the stoichiometric ratio between oxidant (mCPBA) and butadiene units with the polydispersity index within 1.5~2.1,and the functionality (fn) of HTPB was close to 2.0.In comparison with the HTPB prepared by the anionic or free radical polymerization,the HTPB with high cis-1,4 content possesses more regular microstructure (cis-1,4 95%) and extremely low glass transition temperature (Tg -104 ℃).Meanwhile,many high energy-cost and time-consuming processes,such as steam agglomeration and drying in PBD rubber production,and cutting,swelling and dissolving of slab rubber during the preparation of HTPB,can be removed.In short,this process was more economic,efficient and controllable.关键词：HTPB;High cis-1,4 content;Oxidolysis;Reduction;PBD original solution
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发布时间：2021-03-19 - 摘要：The thermo-sensitive collagen hydrogels with semi-interpenetrating polymer network (semi-IPN) were successfully prepared by inducing type Ⅰ collagen into poly(N-isopropylacrylamide) cross-linked network.The chemical composition and pore structure of the semi-IPN gels were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).Swelling ratio measurements and differential scanning calorimetry (DSC) were used to investigate the thermo-sensitivity of hydrogels and contact angles were studied to analyze gels surface hydrophilicity.Additionally,L929 cells' behaviors such as adhesion,proliferation and detachment were carefully studied via cell culture on the surface of PNIPAAm/CollagenⅠ semi-IPN hydrogels in vitro. The results indicated that the PNIPAAm/CollagenⅠ semi-IPN hydrogels present excellent thermo-sensitivity and biocompatibility.Cell cultures of L929 on the semi-IPN hydrogels showed better proliferation and viability than on the PNIPAAm hydrogel.By lowering temperature below the lower critical solution temperature (LCST),L929 cells could spontaneously detach from the surface of gels.Meanwhile,the detached cells were collected for trypan blue staining and hematoxylin and eosin staining.Results showed that extracellular matrix proteins and trans-membrane proteins were hydrolysed by trypsin digestion.Cells spontaneously detached from the semi-IPN hydrogels showed higher viability than those from PNIPAAm hydrogel,which suggesting that the semi-IPN hydrogels have potential value in tissue engineering.关键词：Collagen;PNIPAAm;Semi-interpenetrating hydrogel;Cell behavior;Thermo-sensitive
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发布时间：2021-03-19 - 摘要：Acrylic composite resin modified by calcium lignosulphonate (LSAA) was prepared by solution polymerization using calcium lignosulphonate (LS-Ca) and acrylic acid (AA) as raw materials,and ethylene glycol dimethacrylate (EGDMA) as the cross-linker.LSAA was characterised using Fourier transform infrared spectroscopy (FTIR),scanning electron microscopy (SEM),thermogravimetric analysis (TG) and specific surface analysis.TG result showed that the initial temperature of decomposition was 291.2 ℃ and LSAA was good in thermal stability.LSAA had good adsorption capability to methyl orange (MO) because of the rough surface and abundant mesoporous,as well as the hydroxyl groups on the surface of LSAA.The optimum pH was 3.0 and LSAA had adsorption capacity of 188.33 mgg-1 after 24 h at 298 K.The adsorption of MO on LSAA was an exothermic typical physical adsorption process which was in accordance with both Langmuir and Freundlich isotherm equations.The kinetic study indicated that adsorption followed the pseudo second-order model.Kannan-Sundaram model showed that the adsorption process of MO on LSAA was divided into three stages,the surface adsorption of adsorbent,the slow diffusion of the hole and the slow diffusion of the small hole,and these lines did not pass through the origin,which meant inner diffusion of the particles was not the sole controlling step of adsorption process.关键词：Calcium lignosulphonate;Adsorption;Acrylic composite resin;Methyl orange;Modification
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发布时间：2021-03-19 - 摘要：PVDF/PTW blends were directly prepared by melt blending and the phase behavior of PVDF/PTW blends was expored by using the dynamic rheology and scanning electron microscopy (SEM).As was shown in the plot of dynamic modulus versus frequency for PVDF/PTW blends at 200 ℃,with increasing the content of PTW,the rheological behavior of the PVDF/PTW blends at low frequency deviated from the classical rheological theory,which was corresponding to cole-cole curves of PVDF/PTW blends at 200 ℃.The viscoelastic properties of PVDF/PTW blends were systematically investigated by using master curves of blends obtained from time-temperature superposition (tTS) principle,Han plots and vGP plots.The results showed that tTS principle worked well for PVDF/PTW blends in homogeneous region.On the other hand,in the phase-separated region,the viscoelastic properties of PVDF/PTW blends were different from characteristic thermorheological responses,especially for the characteristic deviations of the storage modulus at low frequencies,and the Han plots and vGP plots also showed the different shapes corresponding to the homogeneous system.These results showed that PVDF/PTW (PVDF/PTW=90/10) (W/W) blend had better miscibility than the others and it was also confirmed by SEM.关键词：Poly(vinylidene fluoride);Ethylene-butylacrylate-glycidylmethacrylate copolymer;Blends;Miscibility;Reheology
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发布时间：2021-03-19 - 摘要：The structure and properties of cellulose acetate (CA) prepared by homogeneous acetylation in ionic liquids (CAHomo) and heterogeneous acetylation (CAHete) were investigated.The characterizations of CAs such as molecular weight,molecular weight distribution,degree of substitution (DS),distribution of acetyl groups and the partial DS at C-2,C-3 and C-6 were determined by GPC, 1H- and 13C-NMR.The DS of CAHomo and CAHete was about 2.50 calculated by 1H-NMR.The distribution of acetyl groups calculated by 13C-NMR was C-6 C-3 C-2 for CAHomo and C-3 C-2 C-6 for CAHete,respectively.In addition,the structure of CAHomo had better uniformity than that of CAHete.Subsequent property studies showed that the chemical structure differences of CAs had tiny effect on their properties,such as crystallinity,solubility and thermal properties.CAHomo and CAHete were all amorphous structure,and they had better solubility in polar organic solvents.The glass transition temperature and thermal stability were similar for these CAs samples.Therefore,CAHomo synthesized by homogeneous acetylation in ionic liquids had similar physical properties as those of CAHete prepared by heterogeneous acetylation,but the structure of CAHomo had better uniformity than that of CAHete.关键词：Cellulose acetate;Characterization;Substituent distribution;Structure and property
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发布时间：2021-03-19 - 摘要：Biodegradable vinyl functional branched copolymers were successfully synthesized by the oxyanionic copolymerization of -caprolactone (-CL) and glycidyl methacrylate (GMA).Potassium hydride (KH) and benzyl alcohol (BA) were employed as the initiators.The structures and properties of the resulted copolymers were studied in detail by Flourier transform infrared spectroscopy (FTIR),size exclusion chromatography (SEC),nuclear magnetic resonance spectroscopy (NMR),differential scanning calorimetry (DSC),thermogravimetric analysis (TGA) and scanning electron microscopy (SEC).The results showed that oxyanions displayed high activity for the copolymerization of -CL and GMA,resulting degradable copolymers with pendant vinyl groups in one step.Increasing the GMA/-CL feed ratio,the weight-average molecular weight of the copolymers increased from 6.70103 to 1.19105,the degree of branching increased from 0.06 to 0.14,but the degree of crystallinity decreased from 47.6% to 0.The NMR results suggested that the copolymer retained up to 67% pendant vinyl groups,which could further be tailored via the thiol-ene click reaction.Due to the large amount of hydroxyl groups,the resulted copolymers could react with toluene-2,4-diisocyanate,forming a degradable polyurethane film.The SEC result showed that the surface of the polyurethane film became very rough after immersing in a lipase buffer solution for 15 days.关键词：Branched polymer;Pendent allyl group;Glycidyl methacrylate;-Caprolactone
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发布时间：2021-03-19 - 摘要：Firstly,monodisperse polystyrene (PS) microspheres with different diameters are prepared.Subsequently,a uniform and smooth Pt film is formed on the PS microsphere surface by ion sputtering,yielding the corresponding PS-Pt core-shell composite microsphere.Finally,surface wrinkling on these PS composite microspheres is induced by solvent swelling.Consequently,PS microspheres with various surface wrinkle patterns are obtained.Hereinto,the effects of experimental parameters (e.g.,Pt film thickness,microsphere diameter and the swelling solvent) on the surface wrinkling behaviors have been investigated systematically.The results reveal that whether the surface wrinkling on the composite microspheres takes place or not,the resulting wrinkling morphologies are determined by the overstress R/cR. Here the overstress can be tuned by the Pt film thickness,microsphere diameter and the swelling degree.It is noted that a power-law dependence of the wrinkling wavelength on Pt film thickness is obtained and the experimental results are in agreement with the results of the theoretical simulation and calculation.Additionally,combining surface wrinkling and surface plasma etching technique,PS microspheres with composite morphologies of nano-protrusion and wrinkles have been prepared by exposure of PS microspheres to oxygen plasma before ion sputtering of the Pt film.It is envisioned that the introduced strategy in principle could be applied to other curved surfaces for expeditious generation of well-defined wrinkle morphologies,which enables not only the fabrication of solids with multifunctional surface properties,but also provides important implications for the morphogenesis in soft materials and tissues.关键词：Polystyrene (PS);Composite microspheres;Surface wrinkling
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发布时间：2021-03-19 - 摘要：In this study,microcapsules with poly(ethyleneglycol dimethacrylate) (PEGDMA) shell were prepared through interfacial free-radical emulsion polymerization.The mixture of dementholized peppermint oil (DPO) and paraffin or caprylic capric triglyceride (GTCC) was used as core materials.The interfacial free-radical polymerization mechanism for forming the PEGDMA shell was proposed.The morphologies of PEGDMA microcapsules prepared with different kinds of emulsifiers,different compositions of core materials and different curing temperature were explored by optical microscope and scanning electron microscope (SEM).SEM images showed that the morphology of microcapsules is sphere as synthesized at 60 ℃ for 1 h by using gum arabic as emulsifier with 1 :1 ratio of DPO/GTCC as core material.Fourier transform infrared-attenuated total reflectance was used to analyze the chemical structure of the microcapsules.An increase of curing temperature can improve the thermal stability of the core material.The thermal properties of core material,PEGDMA microcapsule,and PEGDMA shell were studied by thermogravimetric analysis (TGA),indicating that the microcapsules cured at 60 ℃ for 3 h had a much better thermal stability than pure core materials.The free oil in the microcapsule dispersion measured by ultraviolet (UV) spectrophotometer was 26.5 wt%.Novel PEGDMA microcapsules will find a wide range of applications in personal care,biomedical device,and etc.关键词：Free radical polymerization;Ethylene glycol dimethacrylate;Poly(ethylene glycol dimethacrylate) shell;Microcapsule
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发布时间：2021-03-19 - 摘要：Polyaniline (PANI) electrode material was prepared in an aqueous solution of aniline and sulfuric acid by cyclic voltammetry (CV) using the conductive glass (FTO) as the substrate material.A method of two-step CV with different scanning potential ranges of -0.2-1.2 V and -0.2-0.8 V was carried out to fabricate optimized electrode materials for supercapacitor application.Moreover,the best deposition conditions of this method were also investigated through changing the deposition circles of CV.The morphological structure of PANI was characterized by scanning electron microscopy and infrared spectroscopy,and the cells'capacitive properties in H2SO4/polyvinylalcohol (H2SO4/PVA) gel electrolyte were analyzed by CV,galvanostatic charge/discharge and electrochemical impedance tests.The results revealed that the PANI/FTO electrode had specific capacitance as high as 172.7 mF/cm2 at 2 mV/s,and 92.8% of its initial capacitance still retained after 2000 cycles.Furthermore,the experiment of partition deposition has been conducted,and it was very obvious that the color of PANI/FTO electrode changed from light green to dark green gradually in the process of charging.However,when discharging,the color of PANI/FTO electrode shifted from dark green to light green gradually.关键词：Supercapacitor;Polyaniline;Electrochromism
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发布时间：2021-03-19 - 摘要：A series of electrophosphorescent conjugated fluorene-alt-carbazole copolymers were designed.Metal complex iridium(Ⅲ) bis-(9,9-diethyl-9H-fluoren-2-yl) pyridine (IrFpy) is grafted in the N-alkyl group of carbazole by covalent bond linkage.The copolymers were synthesized by Suzuki polycondensation, the content of metal iridium complex (IrFpy) was 0.25 mol%,0.5 mol% and 1 mol%,respectively.The yellowish light was obtained with the CIE of (0.44,0.56) with the Ir complex (IrFpy) molar ratio in the copolymer of 1 mol%.With the decrease of iridium complex content,the single white light emitting copolymers were obtained due to the incomplete quench of the blue light emission.The electroluminescent devices were fabricated with configuration of ITO/PEDOT:PSS (50 nm)/polymer + PBD (30 wt%) (80 nm)/Ba (4 nm)/Al (150 nm).The best device performance was achieved based on the polymer PF-IrFpy025,which exhibited a maximal luminous efficiency of 3.97 cd/A with CIE of (0.34,0.34),which are very close to the pure white-light point of (0.33,0.33).To investigate the electroluminescent stabilities of white light emitting copolymers PF-Fpy025 and PF-Fpy05,electroluminescent spectra were tested with voltage from 8 V to 13 V.The two copolymers both showed good electroluminescent stabilities,when the voltage was increased from 8V to 13 V.This result indicated that incorporation of the phosphorescent complex into the conjugated polymer side chains was an effective strategy to simultaneously realize high efficiency and relatively stable electroluminescence of phosphorescent polymer white light emitting diodes.关键词：Polymer light-emitting diodes;White light emission;Iridium complexes;Side chain
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发布时间：2021-03-19 - 摘要：A self-healable hydrogel was prepared by self-crosslinking two biocompatible materials oxidized alginate containing dialdehyde groups and PEG with acylhydrazine groups.Oxidation reactions on OH groups at C-2 and C-3 positions of the uronic units of sodium alginate were performed with sodium periodate.PEG with acylhydrazine terminals was synthesized by PEG and hydrazine hydrate.The generation of the self-crosslinked hydrogel relies on the dynamic covalent linkage through acylhydrazone bonds.Fourier transform infrared spectroscopy (FTIR),nuclear magnetic resonance (NMR),universal testing machine and rheometer were used to characterize the structure and properties of the hydrogel.The results demonstrate that the hydrogel has good flexibility and mechanical strength.The gelation time and mechanical properties can be adjusted by the polymer concentration.The hydrogel can repair itself under mild physiological condition without adding any agent.In both of compression and tensile tests,about 90% recovery of stresses was achieved after healing for 24 h.In addition,the pH responsive hydrogel may undergo gel-sol transition by adjusting pH value of the environment and the transition can be repeated several times.The combination of self-healing,pH sensitive,biocompatibility,along with an easy method of synthesis,made this material ideal candidate for further biomedical applications.关键词：Alginate;Hydrogel;Self-healing;Acylhydrazone bond
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发布时间：2021-03-19 - 摘要：First,the ATRP initiator monosubstituted -CD-Br was successfully prepared,which was confirmed by 1H-NMR and MALDI-TOF.And then the water-soluble polymer (-CD-PDMAEMA) modified with -CD at the one end was synthesised by ATRP polymerization.The -CD-PDMAEMA and PF-ADA can form water-soluble nanoparticle(PF-NP) via the host-guest inclusion complexation between -CD and adamantane (ADA) as driving force.Dynamic light scattering (DLS) was employed to measure the effect of weight ratio of -CD-PDMAEMA/PF-ADA on Rh and PDI of PF-NP.The DLS results show that the weight ratio of -CD-PDMAEMA/PF-ADA with 4 :1 could form smaller nanoparticle,the Rh is 119 nm.As well as four diffent self-assembly methods impact on character of nanoparticles were also focused,while fixing the weight ratio of -CD-PDMAEMA/PF-ADA at 4 :1.When 4 mL water was slowly injected into 1 mL THF solution of -CD-PDMAEMA and PF-ADA under ultrasonication,the Rh of nanoparticle is equal to 81 nm.Transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used to exam the morphology of nanoparticles.The results from TEM and AFM show that the nanoparticles are spherical with diameter of 100 nm,which is smaller than the results observed from DLS measuements.It is well-known that PDMAEMA chains exhibit a coil-to-globule transition above their lower critical solution temperature (LCST) in water solution.At last,the Rh of nanoparticles decreases with temperature increase.All these results show that the nanoparticles have the PF polymer as the core,with diameter of 100 nm and the PDMAEMA polymer as the shell with thick ness of 30 nm.关键词：-Cyclodextrin;Polyfluorene;Water-soluble conjugated polymer nanoparticle;Host-Guest inclusion complexation
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发布时间：2021-03-19 - 摘要：The stress relaxation behavior of nylon 1010 samples with the initial strain of 1%,2.8% and 5.1% were investigated under various temperatures for not less than 10 h.The samples were measured at 20,40,60 and 80 ℃ separately.The stress relaxation rate,the residual stress and the activation volume under different experimental conditions were obtained.The results show that there was a certain permanent residual stress in the relaxation process.The reason is that the effect of the crystalline regions in the semi-crystalline nylon leads to a permanent modulus of the system.During the relaxation process,nylon samples with different initial strains showed similar trends.When the relaxation rate reached the maximum,the values of activation volume remained constant for a short period of time,which is in accordance with the principle of stress-aided thermal activation.At this stage the activation unit of the polymer was relaxed,and the relaxation rate -d/dt and the effective stress * showed an exponential relation.With further relaxation,the stress decreased to a certain threshold,activation volume would gradually increase and the independent movement of activation unit was restricted.The internal stress of the polymer gradually relaxed by the cooperative movement of multiple activation units.At this final stage,the value of stress assisted work was constant.The relaxation rate -d/dt and the effective stress * exhibited power-law relation and the power exponent is *V/(kT).关键词：Nylon 1010;Stress relaxation;Activation volume;Residual stress;Stress relaxation rate
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发布时间：2021-03-19 - 摘要：A porous polyurea material with rich amine groups was prepared through one-step precipitation polymerization of toluene diisocyanate and ethylenediamine,with acetonitrile or acetone as the polymerization solvent.By determination of the primary amine groups at ends of the polyurea molecules,it was concluded that 48 h of polymerization was needed for completing the polymerization.Effects of solvents,including acetonitrile,acetone and their mixtures at different mass ratios,on the properties of the porous polyurea were studied.The pore structure of the polyurea was characterized by BET and mercury intrusion,the morphology was observed by scanning electron microscopy and the crystallinity was characterized by X-ray diffraction.Results showed that the porous polyurea samples prepared in acetonitrile have higher specific surface area,higher pore volume and broader pore size distribution than those prepared in acetone.For the polyurea prepared in acetonitrile,both large and small pores ( 200 nm) were present,with a specific surface area of 153.2 m2g-1 and a pore volume of 3.5 cm3g-1; For that prepared in acetone,no small pores below 200 nm were detected by mercury intrusion and by BET,with therefore a much lower specific surface of 7.6 m2g-1 and pore volume of 1.2 cm3g-1.While in the mixture of the two solvents,the surface area and pore volume of the porous polyurea material decreased correspondingly,and the distribution of pore size narrowed with the increase in acetone amount in the binary mixture of the two solvents.The chemical structure of the polyureas was the same regardless of the solvent used in their preparation.XRD test demonstrates that partial ordered structure was present in the porous materials,owing to the heavy presence of hydrogen bonding,particularly the so-called ordered hydrogen bonding,formed between the urea carbonyl and the adjacent amide (NH),which was supported by FTIR analysis.关键词：Toluene diisocyanate;Ethylenediamine;Precipitation polymerization;Porous polyurea
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发布时间：2021-03-19
Research Article
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