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Novel sandwich structured glass fiber Cloth/Poly(ethylene oxide)-MXene composite electrolyte
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作者 Yu-Qin Mao Guang-He Dong +3 位作者 Wei-Bin Zhu Yuan-Qing Li Pei Huang Shao-Yun Fu 《Nano Materials Science》 EI CAS CSCD 2024年第1期60-67,共8页
Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performa... Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performance all-solid-state lithium metal batteries.In this article,a novel sandwich structured solid-state PEO composite electrolyte is developed for high performance all-solid-state lithium metal batteries.The PEO-based composite electrolyte is fabricated by hot-pressing PEO,LiTFSI and Ti_(3)C_(2)T_(x) MXene nanosheets into glass fiber cloth(GFC).The as-prepared GFC@PEO-MXene electrolyte shows high mechanical properties,good electrochemical stability,and high lithium-ion migration number,which indicates an obvious synergistic effect from the microscale GFC and the nanoscale MXene.Such as,the GFC@PEO-1 wt%MXene electrolyte shows a high tensile strength of 43.43 MPa and an impressive Young's modulus of 496 MPa,which are increased by 1205%and 6048%over those of PEO.Meanwhile,the ionic conductivity of GFC@PEO-1 wt%MXene at 60℃ reaches 5.01×10^(-2) S m^(-1),which is increased by around 200%compared with that of GFC@PEO electrolyte.In addition,the Li/Li symmetric battery based on GFC@PEO-1 wt%MXene electrolyte shows an excellent cycling stability over 800 h(0.3 mA cm^(-2),0.3 mAh cm^(-2)),which is obviously longer than that based on PEO and GFC@PEO electrolytes due to the better compatibility of GFC@PEO-1 wt%MXene electrolyte with Li anode.Furthermore,the solid-state Li/LiFePO_(4) battery with GFC@PEO-1 wt%MXene as electrolyte demonstrates a high capacity of 110.2–166.1 mAh g^(-1) in a wide temperature range of 25–60C,and an excellent capacity retention rate.The developed sandwich structured GFC@PEO-1 wt%MXene electrolyte with the excellent overall performance is promising for next generation high performance all-solid-state lithium metal batteries. 展开更多
关键词 Solid polymer electrolyte Ti_(3)C_(2)T_(x)MXene poly(ethylene oxide) Glass fiber cloth All-solid-state Li metal Battery
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Laminar Composite Solid Electrolyte with Poly(Ethylene Oxide)-Threaded Metal-Organic Framework Nanosheets for High-Performance All-Solid-State Lithium Battery 被引量:1
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作者 Na Peng Weijie Kou +3 位作者 Wenjia Wu Shiyuan Guo Yan Wang Jingtao Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期264-273,共10页
Developing laminar composite solid electrolyte with ultrathin thickness and continuous conduction channels in vertical direction holds great promise for all-solid-state lithium batteries.Herein,a thin,laminar solid el... Developing laminar composite solid electrolyte with ultrathin thickness and continuous conduction channels in vertical direction holds great promise for all-solid-state lithium batteries.Herein,a thin,laminar solid electrolyte is synthesized by filtrating–NH 2 functionalized metal-organic framework nanosheets and then being threaded with poly(ethylene oxide)chains induced by the hydrogen-bonding interaction from–NH_(2) groups.It is demonstrated that the threaded poly(ethylene oxide)chains lock the adjacent metal-organic framework nanosheets,giving highly enhanced structural stability(Young’s modulus,1.3 GPa)to 7.5-μm-thick laminar composite solid electrolyte.Importantly,these poly(ethylene oxide)chains with stretching structure serve as continuous conduction pathways along the chains in pores.It makes the non-conduction laminar metal-organic framework electrolyte highly conductive:3.97×10^(−5) S cm^(−1) at 25℃,which is even over 25 times higher than that of pure poly(ethylene oxide)electrolyte.The assembled lithium cell,thus,acquires superior cycling stability,initial discharge capacity(148 mAh g^(−1) at 0.5 C and 60℃),and retention(94% after 150 cycles).Besides,the pore size of nanosheet is tailored(24.5–40.9˚A)to evaluate the mechanisms of chain conformation and ion transport in confined space.It shows that the confined pore only with proper size could facilitate the stretching of poly(ethylene oxide)chains,and meanwhile inhibit their disorder degree.Specifically,the pore size of 33.8˚A shows optimized confinement effect with trans-poly(ethylene oxide)and cis-poly(ethylene oxide)conformation,which offers great significance in ion conduction.Our design of poly(ethylene oxide)-threaded architecture provides a platform and paves a way to the rational design of next-generation high-performance porous electrolytes. 展开更多
关键词 all-solid-state lithium battery ion conduction laminar composite solid electrolyte poly(ethylene oxide)-threaded metal-organic framework nanosheet structural stability
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Studies on the Simultaneous Synthesis of Dimethyl Carbonate and Poly(ethylene terephthalate): I. Catalytic Activity of Metal Acetate in Transesterification of Ethylene Carbonate with Dimethyl Terephthalate 被引量:4
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作者 Dan ZHANG Shu Yong JLA +3 位作者 Yue WANG Jie YAO Yi ZENG Gong Ying WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第12期1607-1610,共4页
A novel direct method for preparation of dimethyl carbonate and poly(ethylene terephthalate) from ethylene carbonate and dimethyl terephthalate has been demonstrated in the presence of metal acetate catalysts, lithi... A novel direct method for preparation of dimethyl carbonate and poly(ethylene terephthalate) from ethylene carbonate and dimethyl terephthalate has been demonstrated in the presence of metal acetate catalysts, lithium acetate dihydrate showed highest catalytic activity with 47.9% yield of dimethyl carbonate. This method was a green chemical process. 展开更多
关键词 Metal acetate ethylene carbonate dimethyl terephthalate dimethyl Carbonate polyethylene terephthalate).
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Recycling and depolymerization of waste polyethylene terephthalate bottles by alcohol alkali hydrolysis 被引量:11
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作者 SUN Cong-hao CHEN Xiang-ping +1 位作者 ZHUO Qiang ZHOU Tao 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期543-549,共7页
In this work,a novel alcohol alkali hydrolysis method was explored for the preparation of terephthalic acid(TPA)from waste polyethylene terephthalate(PET).First,a series of single factor experiments on the depolymeriz... In this work,a novel alcohol alkali hydrolysis method was explored for the preparation of terephthalic acid(TPA)from waste polyethylene terephthalate(PET).First,a series of single factor experiments on the depolymerization rate of waste PET bottles and the yield of TPA were conducted to determine the optimized experimental conditions,in terms of reaction time,reaction temperature,dosage of ethylene glycol and sodium bicarbonate,amount of distilled water and stirring rate.Then IR spectra and elemental analysis were carried out for the characterization of obtained product.Under optimal experimental conditions,over 98%PET can be depolymerized into the target product(TPA)and the purity and yield of TPA are over 97%and 94%,respectively.Both the experimental and analytical results support a feasible process for the preparation of TPA from waste PET.It is expected that this alcohol alkali hydrolysis method can promise an effective way for the sustainable recycling of waste PET. 展开更多
关键词 waste polyethylene terephthalate terephthalic acid alcohol alkali hydrolysis ethylene glycol
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Characterization and Properties of Electroless Nickel Plated Poly (ethylene terephthalate) Nonwoven Fabric Enhanced by Dielectric Barrier Discharge Plasma Pretreatment 被引量:4
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作者 耿亚敏 卢灿辉 +1 位作者 梁梅 张伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第6期715-722,共8页
In order to develop a more economical pretreatment method for electroless nickel plating, a dielectric barrier discharge (DBD) plasma at atmospheric pressure was used to improve the hydrophilicity and adhesion of po... In order to develop a more economical pretreatment method for electroless nickel plating, a dielectric barrier discharge (DBD) plasma at atmospheric pressure was used to improve the hydrophilicity and adhesion of poly (ethylene terephthalate) (PET) nonwoven fabric. The properties of the PET nonwoven fabric including its liquid absorptive capacity (WA), aging behavior, surface chemical composition, morphology of the surface, adhesion strength, surface electrical resistivity and electromagnetic interference (EMI)- shielding effectiveness (SE) were studied. The liquid absorptive capacity (WA) increased due to the incorporation of oxygen-containing and nitrogen-containing functional groups on the surface of PET nonwoven fabric after DBD airplasma treatment. The surface morphology of the nonwoven fibers became rougher after plasma treatment. Therefore, the surface was more prone to absorb tin sensitizer and palladium catalyst to form an active layer for the deposition of electroless nickel. SEM and X-ray diffraction (XRD) measurements indicated that a uniform coating of nickel was formed on the PET nonwoven fabric. The average EMI-SE of Ni-plating of PET nonwoven fabric maintained a relatively stable value (38.2 dB to 37.3 dB) in a frequency range of 50 MHz to 1500 MHz. It is concluded that DBD is feasible for pretreatment of nonwoven fabric for electroless nickel plating to prepare functional material with good EMI-SE properties. 展开更多
关键词 dielectric barrier discharge plasma electroless nickel plating polyethylene terephthalate (PET) surface properties
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Stannous-acetylacetonate:A new catalyst for poly(trimethylene terephthalate) synthesis 被引量:5
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作者 Shu Yong Jia Yu Rong Ren +3 位作者 Liang Ming Liu Dan Zhang Yi Zeng Gong Ying Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第7期827-830,共4页
Stannous-acetylacetonate was prepared efficiently and characterized by ^1H NMR and FT-IR. Its catalytic activity for poly(trimethylene terephthalate) (PTT) synthesis was investigated. By this catalyst, the degree ... Stannous-acetylacetonate was prepared efficiently and characterized by ^1H NMR and FT-IR. Its catalytic activity for poly(trimethylene terephthalate) (PTT) synthesis was investigated. By this catalyst, the degree of esterification of pure terephthalic acid was up to 91.7% after reaction at 260 ℃ for 2 h, while the intrinsic viscosity and content of terminal carboxyl groups of the corresponding PTT polymerized at 260 ℃, 60 Pa for 2 h was 0.8816 dL/g and 17 mol/t,respectively. Stannous-acetylacetonate was more active and promising than tetrabutyl titanate and stannous octoate for PTT synthesis. 展开更多
关键词 poly(trimethylene terephthalate Stannous-acetylacetonate 1 3-PROPANEDIOL
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Flame Retardancy and Thermal Property of Poly (ethylene terephthalate)/Modified Cyclotriphosphazene Composites 被引量:2
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作者 汪娇宁 苏兴勇 +4 位作者 雅兰 陈雯婷 陈飞 陈樱 毛志平 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期384-389,共6页
In this study,hexachlorocyclotriphosphazene( HCCP)modified by boric acid and 3-aminopropyltriethoxysilane( KH-550)in solvent diglyme( FR-HCCP) was used as the flame retardant for poly( ethylene terephthalate)( PET) co... In this study,hexachlorocyclotriphosphazene( HCCP)modified by boric acid and 3-aminopropyltriethoxysilane( KH-550)in solvent diglyme( FR-HCCP) was used as the flame retardant for poly( ethylene terephthalate)( PET) composites. The flame retardancy and thermal property of pure PET and flame-retarded PET composites were mainly investigated. The flame retardancy was investigated by limited oxygen index( LOI) and UL-94 vertical burning test. The results showed that the composites could achieved an increased UL-94 V-0 rating and LOI value 30. 2, when the content of FR-HCCP was just 1%. The pyrolysis-gas chromatography-mass spectrometry( Py-GC / MS) study demonstrated that introducing FR-HCCP into PET would prevent the polymer pyrolysis during heating. TGA analysis showed that the addition of FR-HCCP could improve the char formation of the system. Roman spectra showed the order degree of residue was increasing by adding the additive. The morphology and the chemical structure of the charred residue were detected by SEMand FTIR,respectively. Results demonstrated that a good barrier was formed by the char of the composite,which protected the inside of the composite during burning. 展开更多
关键词 boron-silicon polyPHOSPHAZENE flame retardant poly(ethylene terephthalate)(PET)
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FOURIER TRANSFORM INFRARED STUDIES OF POLY (ETHYLENE TEREPHTHALATE) FILM IN THE GLASS TRANSITION REGION 被引量:1
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作者 钱人元 沈德言 李惠鸣 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第2期150-158,共9页
Three specimens from a solution-cast poly (ethylene terephthalate) (PET) film, one being liquid-N_2 quenched from 92℃(Q), one being slowly cooled from 92℃(SC) and one being quenched and sub-T_g annealed at 67℃(AN),... Three specimens from a solution-cast poly (ethylene terephthalate) (PET) film, one being liquid-N_2 quenched from 92℃(Q), one being slowly cooled from 92℃(SC) and one being quenched and sub-T_g annealed at 67℃(AN), have been studied by specimen difference spectra Q-SC and AN-Q and temperature difference spectra T-70 and T_2-T_1 for every 2℃ steps on heating to 90℃ at 2℃ /min. SC and AN showed more gauche conformers than Q. That means that the PET chain has more trans conformers at higher temperatures and some of these are frozen during quenching through T_g. A band at 1340 cm^(-1) has been found to be complex containing overlapping bands reflecting trans in crystalline regions and trans in amorphous regions. The temperature difference spectra on heating through T_g showed that the spectral changes in Q are gradual while a rather abrupt change occurs in AN at 80—82℃ for the bands at 1340, 1042 and 1020 cm^(-1). No new conformational structure or new vibrational mode is involved. A kind of locking mechanism is suggested which hinders the molecular vibrational changes in AN below T_g until a sudden release occurs at T_g. These locking sites can be nothing else than sites of tighter local packing of chain segments. Consequently it is believed that inter-chain van der Waals attraction energy plays a dominating role in the volume relaxation and sub-T_g annealing of quenched amorphous polymers. 展开更多
关键词 Infrared spectra Glass transition poly ( ethylene terephthalate ) CONFORMATION Enthalpy relaxation.
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In-situ Polymerization-modification Process and Foaming of Poly(ethylene terephthalate) 被引量:4
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作者 仲华 奚桢浩 +1 位作者 刘涛 赵玲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第12期1410-1418,共9页
Most of traditional linear poly(ethylene terephthalate)(PET)resins of relatively low molecular mass and narrow molecular mass distribution have low melt strength at foaming temperatures,which are not enough to support... Most of traditional linear poly(ethylene terephthalate)(PET)resins of relatively low molecular mass and narrow molecular mass distribution have low melt strength at foaming temperatures,which are not enough to support and keep cells.An in-situ polymerization-modification process with esterification and polycondensation stages was performed in a 2 L batch stirred reactor using pyromellitic dianhydride(PMDA)or pentaerythritol(PENTA)as modifying monomers to obtain PETs with high melt strength.The influence of amounts of modifying monomers on the properties of modified PET was investigated.It was found that the selected modifying monomers could effectively introduce branched structures into the modified PETs and improve their melt strength.With increasing the amount of the modifying monomer,the melt strength of the modified PET increased.But when the amount of PENTA reached 0.35%or PMDA reached 0.9%,crosslinking phenomenon was observed in the modified PET.Supercritical carbon dioxide(ScCO2)was employed as physical foaming agent to evaluate the foaming ability of modified PETs.The modified PETs had good foaming properties at 14 MPa of CO2pressure with foaming temperature ranging from 265°C to 280°C.SEM micrographs demonstrated that both modified PET foams had homogeneous cellular structures,with cell diameter ranging from 35μm to 49μm for PENTA modified PETs and38μm to 57μm for PMDA modified ones.Correspondingly,the cell density had a range of 3.5×107cells·cm 3to 7×106cells·cm 3for the former and 2.8×107cells·cm 3to 5.8×106cells·cm 3for the latter. 展开更多
关键词 polyethylene terephthalate in-situ polymerization-modification supercritical carbon dioxide molten-state foaming
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Simultaneous Synthesis of Dimethyl Carbonate and Poly(ethylene terephthalate) Using Alkali Metals as Catalysts 被引量:2
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作者 张丹 王庆印 +3 位作者 姚洁 王越 曾毅 王公应 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期772-774,共3页
Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is ... Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is an excellent green chemical process without poisonous substance. Various alkali metals were used as the catalysts. The results showed alkali metals had catalytic activity in a certain extent. The effect of reaction condition was also studied. When the reaction was carded out under the following conditions: the reaction temperature 250℃, molar ratio of EC to DMT 3 : 1, reaction time 3h, and catalyst amount 0.004 (molar ratio to DMT), the yield of DMC was 68.9%. 展开更多
关键词 ethylene carbonate dimethyl terephthalate dimethyl carbonate poly ethylene terephthalate TRANSESTERIFICATION CATALYST
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Isothermal Crystallization Behavior of Poly (ethylene terephthalate)/Carbon Black Masterbatch 被引量:1
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作者 姜兆辉 金剑 +1 位作者 肖长发 李鑫 《Journal of Donghua University(English Edition)》 EI CAS 2012年第2期123-128,共6页
Poly(ethylene terephthalate) (PET)/carbon black (CB) masterbatch was prepared by melt blending using a separate feeding technique and its homogeneous dispersion morphology was confirmed by transmission electron micros... Poly(ethylene terephthalate) (PET)/carbon black (CB) masterbatch was prepared by melt blending using a separate feeding technique and its homogeneous dispersion morphology was confirmed by transmission electron microscope (TEM). The Avrami and Hoffman-Lauritzen secondary nucleation theories were employed to analyze the effect of high CB content on crystallization kinetics of PET, providing theoretical support for the development of masterbatch with high content of functional components. The Avrami exponents,average values of n,for PET and PET/CB masterbatch are both greater than 3, which indicates three-dimensional growth of crystals. In addition,no significant evidence for regime transition of PET is found applying Hoffman-Lauritzen secondary nucleation theory,though such observations have been reported previously in the literature. Furthermore,appropriate U* value for PET is determined to be 12 800 J/mol. For PET/CB masterbatch,a transition from regime I to regime II around 225℃ is observed with appropriate U* value (12 800 J/mol) . This phenomenon is consistent with a transition point in plot of G versus Tc . The fold surface free energy σe (100. 3 mJ/m 2) of PET is much greater than that of PET/CB masterbatch (48. 3 mJ/m 2) ,which indicates heterogeneous nucleation effect of CB particles. 展开更多
关键词 thermal properties poly(ethylene terephthalate) (PET) carbon black (CB) MASTERBATCH crystallization kinetics
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Thermal degradation and isothermal crystalline behavior of poly(trimethylene terephthalate) 被引量:2
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作者 Jian Liu Shu Guang Bian +2 位作者 Min Xiao Shuan Jin Wang Yue Zhong Meng 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期487-491,共5页
Poly(trimethylene terephthalate) (PTT) is an excellent fiber material. Its thermal degradation and isothermal crystalline behaviors were in this study investigated using thermogravimetric analysis (TGA), thermog... Poly(trimethylene terephthalate) (PTT) is an excellent fiber material. Its thermal degradation and isothermal crystalline behaviors were in this study investigated using thermogravimetric analysis (TGA), thermogravimetric analysis-Fourier transform infrared spectroscopy (TGA-FTIR) analysis, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The thermal degradation mechanism of PTT follows Mclafferty rearrangement principle. The PTTwithintrinsicviscosity(IV) of 0.74 dL/g has a maximum crystallinity of about 55% at 190 ℃, as demonstrated by DSC and XRD measurements consistently. 展开更多
关键词 poly(trimethylene terephthalate Thermal degradation Isothermal crystallization
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Stable Cycling of All-Solid-State Lithium Metal Batteries Enabled by Salt Engineering of PEO-Based Polymer Electrolytes 被引量:1
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作者 Lujuan Liu Tong Wang +6 位作者 Li Sun Tinglu Song Hao Yan Chunli Li Daobin Mu Jincheng Zheng Yang Dai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期67-74,共8页
Poly(ethylene oxide)(PEO)-based polymer electrolytes show the prospect in all-solid-state lithium metal batteries;however,they present limitations of low room-temperature ionic conductivity,and interfacial incompatibi... Poly(ethylene oxide)(PEO)-based polymer electrolytes show the prospect in all-solid-state lithium metal batteries;however,they present limitations of low room-temperature ionic conductivity,and interfacial incompatibility with high voltage cathodes.Therefore,a salt engineering of 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonimide lithium salt(LiHFDF)/LiTFSI system was developed in PEO-based electrolyte,demonstrating to effectively regulate Li ion transport and improve the interfacial stability under high voltage.We show,by manipulating the interaction between PEO matrix and TFSI^(-)-HFDF^(-),the optimized solid-state polymer electrolyte achieves maximum Li+conduction of 1.24×10^(-4)S cm^(-1)at 40℃,which is almost 3 times of the baseline.Also,the optimized polymer electrolyte demonstrates outstanding stable cycling in the LiFePO_(4)/Li and LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)/Li(3.0-4.4 V,200 cycles)based all-solid-state lithium batteries at 40℃. 展开更多
关键词 all-solid-state battery high voltage li-ion conductivity molecular interaction poly(ethylene oxide)
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High-efficiency acetaldehyde removal during solid-state polycondensation of poly(ethylene terephthalate) assisted by supercritical carbon dioxide 被引量:2
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作者 Zhenhao Xi Tian Liu +3 位作者 Wei Si Fenglei Bi Zhimei Xu Ling Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第6期1285-1291,共7页
The concentration of acetaldehyde(AA) is the main quality index of poly(ethylene terephthalate)(PET) used in food and drink packaging.A new method for AA removal has been developed by using supercritical carbon dioxid... The concentration of acetaldehyde(AA) is the main quality index of poly(ethylene terephthalate)(PET) used in food and drink packaging.A new method for AA removal has been developed by using supercritical carbon dioxide(sc CO2) during the solid-state polycondensation of PET.The influence factors of AA removal including the temperature,pressure,reaction time and the size of pre-polymer particles are systematically studied in this work.The results indicate that it is a highly efficient way to obtain high molecular weight PET with relative low concentration of AA.Correspondingly,the polymerization degree of PET could increase from 27.9 to 85.6 while the concentration of AA reduces from 0.229 × 10^(-6) to 0.055 × 10^(-6) under the optimal operation conditions of 230 °C,8 MPa and size of 0.30–0.45 mm.Thermodynamic performance tests show the increasing extent of PET crystallinity due to the fact that the plasticization of sc CO_2 is not obvious with extended reaction time,therefore the increasing crystallinity has no significant influence on AA removal.SEM observations reveal that the effects of sc CO_(2-) induced plasticization and swelling on PET increase significantly with the decrease of prepolymer size,and the surface of PET becomes more loose and porous in favor of the AA removal. 展开更多
关键词 Supercritical CO2 Solid-state polycondensation polyethylene terephthalate Removal of acetaldehyde
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Study of Thermal,Phase Morphological and Mechanical Properties of Poly(L-lactide)-b-Poly(ethylene glycol)-b-Poly(L-lactide)/Poly(ethylene glycol)Blend Bioplastics
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作者 Yodthong Baimark Theeraphol Phromsopha 《Journal of Renewable Materials》 SCIE EI 2023年第4期1881-1894,共14页
A poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide)(PLLA-PEG-PLLA)block copolymer has great potential for use as a flexible bioplastic.Highly flexible bioplastics are required for flexible packaging applicatio... A poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide)(PLLA-PEG-PLLA)block copolymer has great potential for use as a flexible bioplastic.Highly flexible bioplastics are required for flexible packaging applications.In this work,a PEG was incorporated into block copolymer as a plasticizer by solvent casting.PLLA-PEG-PLLA/PEG blends with different blend ratios were prepared,and the plasticizing effect and miscibility of PEG in block copolymer were intensively investigated compared to PLLA/PEG blends.The results indicated that the PEG was an effective plasticizer for the block copolymer.The blending of PEG decreased glass-transition temperature and accelerated the crystallization of both the PLLA and PLLA-PEG-PLLA matrices.The PEG was completely miscible when blended with block copolymer and it improved thermal stability of the block copolymer matrix but not of the PLLA matrix.Film extensibility of PLLA-PEG-PLLA/PEG blends steadily increased as the PEG ratio increased.These non-toxic and highly flexible PLLA-PEG-PLLA/PEG bioplastics are promising candidates for several applications such as biomedical devices,tissue scaffolds and packaging materials. 展开更多
关键词 poly(lactic acid) poly(ethylene glycol) polymer blends phase morphology thermal stability
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THERMALLY STIMULATED SHAPE MEMORY BEHAVIOR OF(ETHYLENE OXIDE-BUTYLENE TEREPHTHALATE)SEGMENTED COPOLYMER 被引量:1
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作者 Xiao-lie Luo Ming-chuan Zhao +2 位作者 Mo-zhen Wang Lu-na Ding De-zhu Ma Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第4期357-361,共5页
The thermally stimulated shape memory behavior of ethylene oxide-butylene terephthalate (EOBT) segmented copolymers with different soft segment molecular weight and hard segment content was investigated. The deformati... The thermally stimulated shape memory behavior of ethylene oxide-butylene terephthalate (EOBT) segmented copolymers with different soft segment molecular weight and hard segment content was investigated. The deformation recovery ratio R-f of the EOBT samples increases with the soft segment molecular weight and the hard segment weight content, while the average overall deformation recovery speed V-r increases with the hard segment content. The temperature of maximum deformation recovery speed (T-M) is determined by the melting temperature of the soft segment crystals and the stability of the crystallized hard segment domains. 展开更多
关键词 ethylene oxide-butylene terephthalate segmented copolymers shape memory crystallized hard segment
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Synthesis and characterization of copolymers of poly(m-xylylene adipamide) and poly(ethylene terephthalate) oligomers by melt copolycondensation 被引量:2
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作者 Fenglei Bi Jianqiang Shao +2 位作者 Zhenhao Xi Ling Zhao Di Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1290-1297,共8页
Poly(m-xylylene adipamide)/poly(ethylene terephthalate)(MXD6/PET) copolymers are synthesized by melt copolycondensation with 1–5 wt% low molecular weight PET oligomers into the MXD6 oligomers at 260 ℃.FR-IR an... Poly(m-xylylene adipamide)/poly(ethylene terephthalate)(MXD6/PET) copolymers are synthesized by melt copolycondensation with 1–5 wt% low molecular weight PET oligomers into the MXD6 oligomers at 260 ℃.FR-IR and1 H NMR analysis results indicate that the interchange reaction has occurred between MXD6 oligomers and PET oligomers. The thermal behavior of copolymers shows that the melting temperature of MXD6/PET copolymers decreases with the increasing of amount of PET oligomers, while the crystallization temperature accordingly increases. And the equilibrium temperature Tm0 is evaluated to be 251.8 ℃ for the copolymers with5 wt% PET oligomer adding, which is very close to that of neat MXD6. The tensile and impact strength of MXD6/PET copolymers are significantly improved than that of pure MXD6 by mechanical properties test, and the microfibril structure in the impact fracture sample's surface reveals the feature of ductile fracture. 展开更多
关键词 polymerization poly(m-xylylene adipamide) polyethylene terephthalate Crystallization Mechanical properties
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Enzymatic Modification of Poly (ethylene terephthalate) Fiber with Lipase from Aspergillus oryzae 被引量:1
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作者 王小花 陆大年 +1 位作者 邵志宇 洪枫 《Journal of Donghua University(English Edition)》 EI CAS 2007年第3期357-361,共5页
Lipase preparation from Aspergillus oryzae could act on ester bonds on the surface of poly (ethylene terephthalate) fibers and a possible hydrolytic product mono (2-hydroxyethyl) terephthalate was released. After ... Lipase preparation from Aspergillus oryzae could act on ester bonds on the surface of poly (ethylene terephthalate) fibers and a possible hydrolytic product mono (2-hydroxyethyl) terephthalate was released. After the iipase modification, there were more carboxyi groups on the treated poly (ethylene terephthalate) fabric surface that resulted in binding with more cationic dyes. Increased hydrophilicity and antistatic ability of poly (ethylene terephthalate) samples were found based on moisture regain, water contact angle and static half decay time. 展开更多
关键词 Aspergillus oryzae polyethylene terephthalate)fiber enzymatic modification LIPASE antistatic ability HYDROPHILICITY
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Preparation and Thermo-Responsive Properties of Poly(Oligo(Ethylene Glycol)Methacrylate)Copolymers with Hydroxy-Terminated Side Chain
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作者 陈杨轶 苏桐 +3 位作者 周仕航 谢晨迪 李京芝 邱夷平 《Journal of Donghua University(English Edition)》 CAS 2023年第6期610-621,共12页
Thermo-responsive random copolymers,poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-(ethylene glycol)methyl ether methacrylate)(P(EO_(2)-co-EO_(4/5)))and poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-ethylen... Thermo-responsive random copolymers,poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-(ethylene glycol)methyl ether methacrylate)(P(EO_(2)-co-EO_(4/5)))and poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-ethylene glycol methacrylate(P(EO2-co-EG4/5))are synthesized via atom transfer radical polymerization(ATRP).The successful synthesis and the narrow polydispersity index(PDI)of two copolymers are indicated by 1H nuclear magnetic resonance(1H-NMR)and gel permeation chromatography(GPC)analyses.The transition behaviors of polymers in the aqueous solution are demonstrated by changes in turbidity and particle sizes.The transition behavior of P(EO2-co-EG4/5)is found to be milder than that of P(EO2-co-EO4/5).Moreover,the presence of hydrogen bonds without thermo-responsive properties established by hydroxyl groups in the end-side chain of P(EO_(2)-co-EG_(4/5))hinders the dehydration at the transition temperature(TT).Attenuated total reflection Fourier transform infrared spectrometry(ATR-FTIR)analysis along with contact angle measurements reveals that both P(EO_(2)-co-EO_(4/5))and P(EO_(2)-co-EG_(4/5))films undergo phase transitions from hydrophilicity to hydrophobicity above TT.By examining the swelling and collapse behaviors of the polymer films during phase transitions,it can be concluded that the end hydroxyl groups may establish hydrogen bonds with neighboring ether groups within the films,which remain intact throughout the phase transition process due to their strong bonding interactions.This leads to an increase in steric hindrance within swollen films thereby impeding dehydration processes and inducing hysteresis during phase transitions. 展开更多
关键词 thermo-responsive property poly(oligo(ethylene glycol)methacrylate) polyethylene glycol methacrylate hydroxy-terminated side chain contact angle phase transition
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CRYSTALLIZATION BEHAVIOR OF PURE AND ADDITIVE-CONTAINING POLY (ETHYLENE TEREPHTHALATE)
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作者 卜海山 金毅敏 +1 位作者 胡家伦 于同隐 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第3期242-249,共8页
The isothermal crystallization of poly (ethylene terephthalate ) (PET),which is free of catalyst, stabilizer, oligomer and diethylene glycol (DEG), was studied by DSC. The crystallization behaviour of pure PET is diff... The isothermal crystallization of poly (ethylene terephthalate ) (PET),which is free of catalyst, stabilizer, oligomer and diethylene glycol (DEG), was studied by DSC. The crystallization behaviour of pure PET is different from commercial PET and a reasonable explanation is presented. The influences of catalyst, stabilizer, oligomer and DEG on the crystallization of pure PET were examined. It is shown that catalyst (Manganese acetate)and stabilizer (Triphenyl phosphite) result in an increase of the crystallization rate of PET; on the contrary, DEG and oligomer (cyclotetramer) result in a reduction of the crystallization rate. When catalyst and stabilizer coexist together, both of them promote the crystallization at lower temperature ,only a smaller effect was found at higher temperature, it is evident that metal phosphite is formed between the catalyst and stabilizer at higher temperature. 展开更多
关键词 poly (ethylene terephthalate) ADDITIVE Isothermal crystallization NUCLEATION Nucleating agent
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