最新刊期
卷 ， 期 10 ， 2011
- 摘要：Recent studies on eucommia ulmoids (EU) gum are summarized.The present paper firstly introduced the extraction methods,macromolecular structure and biological synthesis mechanism of EU gum; and introduced the crystalline characterisitics of EU gum,such as the determination of crystal form of EU gum,the preparation and the conversion of various crystal forms of EU gum,the melting points and fusion enthalpy of EU gum,the crystallization rate and its dependent factors of EU gum and so on.Then,this paper highlighted the studies of application of EU gum which was made breakthrough progress by our group in recent years.Such as,the three stages during the vulcanization progress of EU gum,the critical elastic turning law of EU gum,the two active dynamic mechanical zones of EU gum controlled by temperature,the five dynamic mechanical behaviours of EU gum controlled by crosslinking degree,and the comparative studies of EU gum and synthetic trans -1,4-polyisoprene and so on.In the end,the future direction of study of EU gum is envisaged.关键词：Eucommia ulmoides gum;Biological synthesis;Crystalline characteristic;Dynamic mechancial properties
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发布时间：2021-03-19
Reviews
- 摘要：The article highlights the recent approaches on the design and synthesis of drug delivery systems with a dynamic covalent bond,i.e.benzoic-imine,that renders the responsiveness of the vehicles to the pH changes under physiological conditions.Although the characteristics of Schiff base in chemical compounds and polymers have been well documented,recent reports demonstrate the advantages of the derivative benzoic-imine bond on the construction of pH sensitive polymeric micelles,nanoparticles and injectable hydrogels for pharmaceutical applications.In those systems,the benzoic-imine linkage is stable at physiological pH (7.4),and hydrolyzes following a pH drop to mild acidic,which covers the extracellular pH of solid tumor (6.5),endosome and lysosome environments (5~6.5).Therefore the benzoic-imine containing delivery systems are promising in tumor-targeting and intracellular delivery.关键词：Dynamic covalent bond;Benzoic-imine;pH responsible;Drug delivery
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发布时间：2021-03-19
Feature Articles
- 摘要：Polyetherimide (PEI)/SiO2 composites were in situ prepared via sol-gel process in the presence of tetraethyl orthosilicate (TEOS) in a mixed solvent of N,N-Dimethylacetamide/tetrahydrofuran (DMAc/THF).Electronic microscopy was used to check dispersion quality in transmission mode and scanning mode,and the results showed that SiO2 particles could be uniformly dispersed in the composite under a certain amount (20 wt%) and the average size of the particles could be controlled within a compass of 80~300 nm.However,glomeration may occur if the concentration of SiO2 particles was beyond this range.Results of Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that the glass transition temperature (Tg) and decomposition temperature (Td) of PEI were improved by introducing SiO2 particles.The phase separation morphology of blends of 4,4'-diaminodiphenyl sulphone cured epoxy with PEI or PEI/SiO2composite was investigated by SEM and it showed that the introduction of SiO2 particles could reduce the size of the dispersion phase (PEI rich phase).Dynamic rheological measurement of epoxyresin(ER)/PEI/silica blends with different silica particle content was conducted at same isothermal temperature.The onset time of phase separation decreased as silica particles in the blend system increased because the silica particles could act as catalyst in the polymerization reaction and make the phase separation easier to occur.After that,the viscosity of system with higher particle concentration grew faster and made the phase separation process ends in an earlier stage.Dynamic mechanical thermal analysis (DMTA) and impact tests showed that using PEI/SiO2 as the modifier could enhance the modulus and toughness property of the epoxy resin system simultaneously.关键词：Sol-gel;PEI;Composite;Epoxy resin
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发布时间：2021-03-19 - 摘要：Shape memory polyurethane-silica (SMPU-SiO2) hybrids were prepared in situ via sol-gel process with SMPU and tetraethoxysilane (TEOS) as precursor,solid acid p-toluenesulfonic acid (PTSA) as catalyst and the water in air as the source of hydrolysis reaction,then the hybrids prepared were applied to aramid fiber reinforced flexible composites to improve the interfacial compatibility between aramid fiber and SMPU matrix.Meanwhile,the interfacial bonding property between aramid fiber and resin matrix is inferior due to surface inert property of aramid fiber,thus,aramid fiber was modified by phosphoric acid solution to increase the surface activity.Fourier transform infrared (FTIR) spectrometer,X-ray photoelectron spectroscope (XPS),universal tensile instrument,low-temperature thermal dilatometer and polarized light micrograph (PLM) were used to characterize the surface groups,single fiber strength of aramid fiber and the interfacial property of aramid fiber/SMPU matrix composites.The results show that the surface active groups and the single fiber strength are increased by the treatment of phosphoric acid.And the interfacial shear strength (IFSS) between aramid fiber functionalized with 10 wt% phosphoric acid and SMPU is enhanced.Meanwhile,the addition of SiO2 can effectively lower the coefficient of thermal expansion of SMPU around its glass transition temperature ( Tg ) and increase the IFSS between aramid fiber and matrix remarkably.关键词：Shape memory polyurethane;Hybrid;Aramid fiber;Composites;Interfacial shear strength
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发布时间：2021-03-19 - 摘要：Poly(succinimide) (PSI),obtained by polymerization of aspartic acid,reacted with dodecylamine (DDA) and then hydrolyzed under basic condition for preparing an amphiphilic comb-polymer PASP-Na-g-DDA.By varying the molar ratio of DDA and PSI,a series of polymers was synthesized with different grafting level of DDA.Then their structure was characterized by gel permeation chromatography (GPC) and 1H-nuclear magnetic resonance (1H-NMR).The results showed that the targeted products were prepared successfully,and the molecular weight increased when the ratio of hydrophobic chains DDA increased.Also,it was studied that how the ratio of hydrophilic chains and hydrophobic chains affects the properties of the micelles formed by these polymers and it was revealed that only the percentage of hydrophobic chains reached up to 33.3% or above could the polymers form micelles; the critical micelle concentration (CMC) value of the polymer of which the grafting level was 33.3% was 1.259 10-3 mg/mL.The particle sizes of the micelles formed by the polymers were tested by dynamic light scattering (DLS):along with increasing the ratio of DDA in the polymer chain,the hydrodynamic diameter of the micelles decreased from 136 nm to 97 nm; even spherical micelle was observed under transmission electron microscope (TEM).关键词：Amphiphilic comb-polymer;Grafting level;Micelle;Water solution
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发布时间：2021-03-19 - 摘要：A novel biodegradable poly(glyceric acid) (PGA) was synthesized by the polycondensation of glyceric acid.The hydrophobic and biocompatible molecule cholesterol was immobilized on the pendant functional group of PGA.The micelles were formed by the self-assemble driven by the hydrophilic-hydrophobic interaction.Anti-tumor drug doxorubicin was loaded in the micelles to study the drug release profile.The anti-tumor effects in vitro were evaluated with liver cancer cell HepG2. The results demonstrated that the content of cholesterol grafted was nearly the same as the feeding dose.The micelles of poly(glyceric acid)-g-cholesterol were formed in phosphate buffer solution (PBS) and the critical micellization concentration was 63 g/mL.The micelles were spherical with narrow size distribution; the average diameter was around 120 nanometers.The drug-loading rate and entrapment efficiency of the micelles with 5 mol% cholesterol content in the copolymer were 18.71% and 46.78%,respectively.The sustaining drug release time of the micelles was as long as 12 h.The study of cytotoxicity found that the micelle was nontoxic when the concentration was below 0.5 mg/mL and it showed low cytotoxicity when the concentration was 1 mg/mL.The in vitro anti-tumor effect study showed that the drug loaded micelles could enter into the cancer cells by endocytosis,and the anti-tumor effect of the micelles was better than that of free doxorubicin.关键词：Biodegradable;Poly(glyceric acid)-g-cholesterol;Micelle;Drug release
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发布时间：2021-03-19 - 摘要：The six-arm star-shaped amphiphilic block copolymers poly(-caprolactone)-b-poly(2-hydroxyethyl methacrylate) (6sPCL-b-PHEMA) were prepared by a combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP).The synthesis procedure was composed of three step reactions:First,6sPCL homopolymers were prepared via ring-opening polymerization of -caprolactone by using dipentaerythritol with 6 hydroxyl functional groups as an initiator; Second,6sPCL was functionalized to get macroinitiator 6sPCL-Br for ATRP; Third,atom transfer radical polymerization of 2-hydroxyethyl methacrylate (HEMA) from the macroinitiator 6sPCL-Br was conducted by using copper (Ⅰ) bromide ( Cu(I)Br) and 2,2'-bipyredine (Bpy) as catalyze system to synthesize the star block copolymer 6sPCL-b-PHEMA.Molecular structure of 6sPCL-b-PHEMA was confirmed by 1H nuclear magnetic resonance (1H-NMR) and Fourier transform infrared (FTIR) spectroscopy.Thermal behavior and hydrophilicity of obtained 6sPCL-b-PHEMA were measured by DSC and water contact angle,respectively.The melting point (Tm),crystallization temperature (Tc) and crystallinity (Xc) of the 6sPCL-b-PHEMA were reduced with an increasing of the length of the PHEMA block until the polymers changed into amorphous,in addition,the hydrophilicity of the polymers increased visibly.关键词：Star-poly(-caprolactone);2-Hydroxyethyl methacrylate;Amphiphilic diblock copolymers;Atom transfer radical polymerization
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发布时间：2021-03-19 - 摘要：Oxidative polymerizations of methyl methacrylate (MMA) catalyzed by complexes of transition metal halides in high oxidation states were investigated.First,CuBr2/2,2'-bipyridine (bPy)-catalyzed oxidative polymerizations of MMA in the presence of poly(2-(N,N-dimethylamino)ethyl methacrylate) were performed in different solvents.When cyclohexanone was used as a solvent,only poly(methyl methacrylate) (PMMA) was obtained,suggesting redox initiation between CuBr2/bPy and tertiary amines in cyclohexanone is negligible.Second,oxidative polymerizations of MMA catalyzed by different complexes were carried out.Complexes of CuCl2,CuBr2or FeCl3with bPy,N,N,N',N,N-pentamethyldiethylenetriamine or N,N,N',N'-tetramethylethylenediamine can catalyze oxidative polymerizations of MMA,and polymerization rates increased with the increase of the catalyst concentration.Molecular weight of PMMA increases with monomer conversions initially and maintains constant later.Last,atom transfer radical polymerization (ATRP) chain extension using PMMA from the oxidative polymerizations at different conversions was performed.The results show the CX functionality of PMMA chains at low conversion was also 100%,and it decreased sharply with conversions.Two different mechanisms were conceived to contribute to the oxidative polymerization of MMA:(1) the complexes form ATRP initiators and catalysts with MMA via monomer addition,and then ATRP proceeds to give rise to PMMA chains with CX terminal groups; (2) the complexes catalyze/initiate conventional free radical polymerizations of MMA.关键词：Methyl methacrylate;Transition metal halides in high oxidation states;Atom transfer radical polymerization;Generation of activator via monomer addition;Redox initiation
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发布时间：2021-03-19 - 摘要：A polyacrylonitrile-based carbon fiber modified with multi-walled carbon nanotubes (MWNTs) was prepared in this paper.Three chitosan derivatives,phthaloyl chitosan(PhthCS),naphthoyl chitosan and carboxymethyl chitosan,were used for surface treatments of MWNTs in order to improve their dispersion and stability.Acidizing MWNTs and original MWNTs were also used for comparison with the MWNTs treated with chitosan derivatives.Results indicate that the dispersion and stability of PhthCS-MWNTs were improved significantly in those solvents possessed of polarity from 6 to 10. The effects of molecular weight and concentration of PhthCS on the dispersion stability of the MWNTs were evaluated.Results of transmission electron microscopy and element analysis of the MWNTs reveal that part of MWNTs surfaces are coated by a layer of PhthCS with the thickness of 5 ~ 10 nm,which changes the surface properties and dispersion stability of the MWNTs.A composite PhthCS-MWNTs/carbon fiber was fabricated through gel-spinning,preoxidation,low-temperature carbonization and high-temperature carbonization.SEM results exhibit that the PhthCS-MWNTs dispersed uniformly and oriented preferentially within the composite fibers,which led to improved mechanical properties of the composite carbon fiber.The tensile strength of the composite carbon fiber with 0.5% PhthCS-MWNTs is 19.8% higher than that of the carbon fiber without MWNTs.And the Youngs modulus of the composite carbon fiber containing 3% PhthCS-MWNTs is 13.86 GPa,which is 122% higher than that of the carbon fiber without MWNTs.However,the elongation at break of the composite carbon fiber changed scarcely by adding the PhthCS-MWNTs.关键词：Chitosan derivative;Carbon nanotubes;Composite fiber;Dispersion property
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发布时间：2021-03-19 - 摘要：The dissolubility of chitosan was studied in four kinds of imidazole-based ionic liquids 1-butyl-3-methylimidazolium chloride ([BMIM]Cl),1-butyl-3-methylimidazolium acetate ([BMIM]Ac),1-allyl-3-methylimidazolium chloride ([AMIM]Cl) and 1-ethyl-3-methylimidazolium acetate ([EMIM] Ac) respectively.The possible dissolution mechanism of chitosan in these ionic liquids was suggested,and the chemical structures,thermal stabilities and crystalline forms of the native chitosan and regenerated chitosan from these ionic liquids were analyzed by FTIR,TGA and XRD,respectively.The results show that,chitosan can be dissolvd without derivatization by all the four kinds of ionic liquids,and the dissolubility of chitosan in these ionic liquids is mainly related to the anions of ionic liquids,but also influenced by cations of ionic liquids.The dissolving power of the two kinds of acetate ionic liquids for chitosan is stronger than that of the two kinds of chloride ionic liquids,and that of [EMIM]Ac is the strongest.15.5 wt% of chitosan dissolved in [EMIM]Ac can be achieved at 110℃.The dissolution concentration of chitosan in these ionic liquids increases,but the viscosity-average molecular weight of it decreases with the increasing of temperature and the prolongation of time.The thermal stability of the regenerated chitosan from [BMIM]Cl,[AMIM]Cl,[BMIM]-Ac and [EMIM]Ac respectively increase gradually,which is consistent with the dissolving power of these ionic liquids for chitosan,but the thermal stability of the regenerated chitosan from the four kinds of ionic liquids decreases compared with that of native chitosan.A transition of -chitosan to -chitosan may occur during the dissolving and the recovering processes.关键词：Ionic liquid;Chitosan;Dissolubility;Regeneration
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发布时间：2021-03-19 -
EFFECT OF MONOMER PROPERTY AND CONFIGURATION ON FLEXIBILITY AND DIPOLE OF POLY(VINYL HALIDES) CHAINS
摘要：The improved mean-square radius of gyration and dipole moment of polymers with dipole substitutes are deduced by the rotational-isomeric-state model and the generator matrix method, and used to investigate the configuration-conformation dependent property of poly(vinyl halides), including the relation of them with the conformational energy, the chain tacticity and temperature. It is found that the differences of characteristic ratios, the temperature coefficients and conformational energy dependent property for stereo-regular poly(vinyl halides) polymers are obvious, especially for the isotactic and syndiotactic chains. The differentiates of the dipole ratios with respect to the first conformational energy E of the syndiotactic poly(vinyl halides) are in -0.62~0.05 (J/mol)-1 for instance. However, the unperturbed dimensions of stereo-irregular poly(vinyl halides) chains are rather close to each other. The dipole characteristic ratios of atactic poly(vinyl fluoride), poly(vinyl chloride) and poly(vinyl bromide) are obtained to be 0.80, 0.69 and 0.59, respectively, and their temperature coefficients are -0.0710-3~-0.5310-3K-1, which are in agreement with the experiment dada. The results show that the effect of monomer property and configuration on the flexibility and dipole properties of poly(vinyl halides) is remarkable.关键词：Poly(vinyl halides);Side group;Conformational energy;Configuration;Radius of gyration;Dipole moment- 32
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发布时间：2021-03-19 - 摘要：Poly(2-hydroxyethyl methacrylate) (PHEMA) was grafted from initiator-immobilized gold surfaces via activator generated by electron transfer atom transfer radical polymerization (AGET ATRP) to repel nonspecific protein adsorption and immobilize biotin for specific avidin binding.The surface polymerization of HEMA was demonstrated by FTIR and contact angle measurements.The bioinertness of the PHEMA-modified surfaces was systematically studied.125I-labeled protein (Fg,HSA and Lys) adsorption experiments showed that modification with PHEMA could decrease nonspecific protein adsorption by 82% at least.Cell adhesion results indicated that the Au-PHEMA surface could,to a great extent,resist the adhesion of L929,L02 and endothelium cell (EC).L929 showed slight adhesion while L02 and EC could not adhere at all.PHEMA-biotin modified surfaces with varied PHEMA thickness were prepared with different reaction time,and all these surfaces showed good nonspecific protein-repellant property.In the specific FITC-avidin adsorption experiments,the fluorescence was undetectable when the thickness of PHEMA was below 16 nm due to fluorescence quenching.The fluorescence increased with the thickness between 16 nm and 49 nm.The best signal-to-noise ratio was obtained when the thickness was above 49 nm.The optimized PHEMA-biotin surface performed quite well in the QCM and fluorescence bio-detections and showed potential applications as a substrate of biochip.关键词：Poly(2-hydroxyethyl methacrylate);Bio-detection;Fluorescence;Protein adsorption;Gold surface
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发布时间：2021-03-19 - 摘要：A novel flame-retardant synergist,thermalplastic boron-containing phenol-formaldehyde resin (BPF),was designed and successfully synthesized to modify Magnesium hydroxide (MH) flame retardant polyamide-6 (PA6).The synthesized BPF was characterized by FTIR,1H-NMR,XRD and TGA,etc.The experiment results showed that BPF possessed good charring performance,about 61.4 wt% solid residue remained even after heating to 750℃ for MH/BPF/PA6 system.The degraded BPF produced glassy B2O3 covering on the surface of the burning material,and effectively isolated the oxygen from interior material,therefore remarkably enhanced the flame retardancy of the material,reaching UL94-1.6mm V0 rating.BPF also served as an efficient lubricant and greatly improved the processability of the material.In addition,BPF did not deteriorate the mechanical properties of the flame retardant material,showing comprehensive modification effects on MH flame retardant PA6.关键词：Boron-containing phenol-formaldehyde resin;Char former;Magnesium hydroxide;Synergistic effect flame retardant;Polyamide-6
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发布时间：2021-03-19 - 摘要：A series of copolymers based on L -menthyl acrylate ( L -MtA) and 2,5-bis(4'-hexyloxyphenyl)styrene (BHPSt),namely L -MtA(x)- co -BHPSt(1-x),were prepared via conventional radical copolymerization.UV-Vis absorption and 1H-NMR spectra were used to determine the compositions of the resultant copolymers.Based on the copolymer composition from UV-Vis absorption spectra,the reactivity ratios of BHPSt ( r BHPSt) and L -MtA ( rL -MtA) were estimated as 2.46 and 0.36,respectively,with Kelen-Td's linearization method,implying a random nature of the copolymer.All the copolymers displayed chiroptical properties distinguished from the corresponding monomer mixtures,an indicative of the formation of new chiral structure.When the content of PHPSt was large enough,the copolymer exhibited CD patterns similar with that of optically active helical poly{(+)-2,5-bis[4'-(( S )-2-methylbutoxy)phenyl]styrene},suggesting BHPSt segment was long enough to form stable helical conformation and an excess of screw sense was induced by chiral L -MtA.This work provides an efficient and simple method to obtain optically active helical polymers from achiral vinyl monomer through radical polymerization.关键词：Specific optical rotation;Optically active copolymer;Chirality transfer;Radical polymerization;Reactivity ratio
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发布时间：2021-03-19 - 摘要：Isophorone diisocyanate was first reacted with bis(3-(1-methoxy-2-hydroxypropoxy) propyl) terminated polysiloxanes (PMTS) to attach cyanate groups to polysiloxane chain terminals,followed by reaction of these cyanate-containing polysiloxanes with poly(propylene glycol) to get polysiloxanes modified polyurethane prepolymers (PSU).Hydroxyethyl acrylate (HEA) was then used as coupling agent to react with the PSU to introduce vinyl groups in order to conduct graft-polymerization with acrylics in the subsequent step to finally get polysiloxane-polyacrylic modified polyurethane (PSU-H-AC) ternary grafting hybrid latexes.Non-grafting polysiloxane-polyacrylic-polyurethane (PSU-AC) ternary hybrid latexes were also prepared under the same experimental conditions without HEA used.Results revealed that,regardless of use of HEA,the particle size of the ternary latexes was decreased when PMTS was used.This decrease was more pronounced with a narrower size distribution in PAC grafted ternary latexes than that observed in the latexes without HEA,i.e.PSU-AC series.Higher surface tension in the PAC grafted ternary latexes was also detected as compared with the corresponding ternary latexes without grafting between PU and PAC.Examination of the latex film morphology on the intersection by SEM showed that homogeneous latex films without any phase separation were obtained from the ternary latexes when HEA was used,while aggregates and defaults were observed in the ternary films without HEA.Both measurements of water absorption of the films and of contact angle of water on surface of the films indicated that water resistance was significantly enhanced by PAC grafting on PU through incorporation of HEA during the preparation of the ternary latexes.Employment of PMTS of different molecular weight in the latex preparation and property characterization demonstrated that,to achieve an optimum for the performance of the ternary latex films,molecular weight of PMTS should be limited to 2000 and its content should be not less than 5 wt% in PMTS-PU prepolymers.关键词：Polyurethane modification;Acrylic monomers;Hydroxyalkyl polysiloxane;Hydroxyethyl acrylate;Tricomponent hybrid latex
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发布时间：2021-03-19 - 摘要：Calcium stearate modified nano-CaCO3 (CaSt-nano-CaCO3) was prepared,and iPP /calcium stearate modified nano-CaCO3 (iPP/CaSt-nano-CaCO3) was prepared by melt blending iPP with CaSt-nano-CaCO3 particles.Compared with pure iPP,the addition of CaSt-nano-CaCO3and nano-CaCO3particles both increased flexural strength and flexural modulus of iPP,and impact strength was also improved in these two series composites.In comparison with iPP/nano-CaCO3,the impact toughness of iPP/CaSt-nano-CaCO3composites was improved slightly,while the flexural modulus of iPP/CaSt-nano-CaCO3was obviously increased.Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) tests showed that with increasing CaSt-nano-CaCO3content,the crystallization temperature and the nucleating ability of the composites were all increased.The crystallization temperature of iPP/CaSt-nano-CaCO3is lower than that of iPP/nano-CaCO3 with the same filler content,indicating that the nucleating ability of CaSt-nano-CaCO3is weaker than that of nano-CaCO3 in iPP matrix.Wide-angle X-ray diffraction (WAXD) results showed the composites did not exhibit crystal form after addition of nano-CaCO3and CaSt-nano-CaCO3 particles.Compared with iPP/nano-CaCO3,the presence of calcium stearate increases the melt flow rate (MFR) of iPP composite with the same filler content,implying that the processability of the composites will be improved with the modification of nano-CaCO3 with calcium stearate.关键词：Calcium stearate;Nano-CaCO3;Polypropylene composites;Mechanical properties;Crystallization
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发布时间：2021-03-19 - 摘要：The multi-walled carbon nanotubes (MWCNT) were modified using sodium dodecyl sulfate(SDS) as the aid and the SDS treated MWCNT was named as SCNT.We successfully prepared the multi-walled carbon nanotubes/poly(ethylene terephthalate)(MWCNT/PET) composites and SCNT/PET composites with the desired filler content.The effects of the SDS on the MWCNT/PET composites were investigated from several aspects such as microstructure,electrical conductivity,crystallization behavior and mechanical properties.The results showed that SDS treatment can effectively improve the dispersion of MWCNT in the PET matrix,accelerate the construction of the electrical conducting networks.The percolation threshold of the composites can be dramatically decreased from 2.35 wt% to 0.18 wt%.At the 1 wt% filler content,MWCNT cannot increase the electrical conductivity of the PET composites,but SCNT induced a dramatic increase of about 10 orders of magnitude in the electrical conductivity of the PET composites.SCNT not only increased the electrical conductivity of the PET composites,but also more effectively improved the mechanical properties of the PET composites compared with MWCNT.At the 1 wt% SDS treated MWCNT content,SDS treated MWCNTs increase the tensile strength of PET matrix by about 31% and the tensile modulus of PET matrix by about 58%.Not like MWCNT/PET composites,SCNT/PET composites increase the tensile strength with increasing filler content after 1 wt% loading.Being similar to MWCNT,SCNT could act as a nucleating agent to shift the crystallization temperature of PET matrix to higher temperatures but decrease crystallinity of PET matrix with increasing filler content.The role of SDS in these MWCNT/PET composites has been explored in detail.关键词：Multi-walled carbon nanotube;Sodium dodecyl sulfate;Poly(ethylene terephthalate);Electrical conductivity
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发布时间：2021-03-19
Research Article
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