最新刊期
卷 ， 期 2 ， 2009
- 摘要：Gene therapy shows great promise to treat both acquired and inherited diseases.Numerous gene delivery systems based on viral and nonviral vectors have been developed to protect plasmid DNA and facilitate cell binding and internalization.Nevertheless,it is still a challenge to deliver DNA to target cell population and particular location by injection or systematic delivery due to the immune responses and DNA complex aggregation,degradation,and clearance from the tissue.Polymers loaded with gene or vector/gene complexes can realize the controlled release of gene delivery systems and direct gene delivery to target tissues.This technique,known as “substratemediated transfection",overcomes the extracelluar barriers of gene delivery,sustains the gene release,decreases the toxicity and consequently improves the gene transfection efficiency.Most commonly,the polymers for the controlled release of gene delivery systems are biodegradable polymers.Using these polymers,a variety of formulations of controlled release systems,including nanoparticles,microspheres,implantable matrices and scaffolds,can be fabricated.This review focuses on the recent developments in the polymers used for the controlled release of gene delivery systems,with emphasis on their applications in gene therapy and tissue engineering.These polymers are classified as natural polymers and their derivatives such as collagen,atelocollagen,gelatin,fibrin,glycosaminoglycans,chitosan,alginate,and agarose,and synthetic polymers including poly(lactide-co-glycolide),poly(lactic acid),functionalized poly(lactic acid),poly(orthoester)s,poly( β-amino ester)s,polyanhydrides,polyurethanes and poly(ethylene-co-vinylacetate).Looking to the future,through exquisite adjusting of the chemical and physical characteristics of the polymers,optimally engineered properties may be created to gain greater control over gene expression and cell growth.
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发布时间：2021-03-19
Reviews
- 摘要：Gene therapy is a promising approach to treating diseases that caused by genetic defects or mutation.Non-invasive imaging of gene is a powerful tool in understanding the biodistribution and pharmacokinetics of vectors after in vivo administration.In the current research,amphiphilic copolymers,which were utilized to deliver a magnetic resonance imaging (MRI) contrast agent and pDNA simultaneously,were obtained by modifying hyperbranched polyethylenimine with biodegradable hydrophobic segment (PCL).Synthesis of the copolymer was presented in details and chemical characterization of these copolymers was carried out using 1H-NMR spectroscopy and FT-IR spectrum.The polyethylenimine-g-poly(ε-caprolactone)(PEI-g-PCL) could self-assemble into nanoparticles were between 130 to 160 nm in diameter and displayed zetapotentials between +30～40 mV.The morphology investigated by SEM showed PEI-g-PCL aggregates were micellar structure.The MRI contrast agents-carrying capacity of these polymeric micelles was evaluated by using hydrophobic superparamagnetic iron oxide nanoparticles (SPIO) as the model contrast agents.In addition,this kind of polymeric micelles have been evaluated in vitro as nonviral gene delivery systems. SPIO could be loaded into the hydrophobic core of PEI-g-CL micelle by emulsion/solvent evaporation technique.The PEI-g-PCL micelles were capable of complexing plasmid DNA into nanoparticles with diameters about 200 nm,and these complexes transfect 293 cells with high efficiency.These results suggest that PEI-g-PCL has the potential combined application in gene delivery and MRI diagnosis.
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发布时间：2021-03-19 - 摘要：A dermal equivalent applied in the treatment of scalds has been attracting much attention.We report here the fabrication of a bilayer dermal equivalent (BDE) composed of collagensulfonated carboxymethyl chitosan (SCC) porous scaffold and silicone membrane,and its application for accelerating the healing of skin scalds in a Bama miniature pig model.Firstly,the SCC was synthesized,and its chemical structure was characterized by FTIR and 1H-NMR.Then the effect of the ratio of the SCC on the microstructure of the collagen-SCC porous scaffolds was investigated.Sheet-like structure and bigger pores in the scaffolds appeared gradually along with the increase of the SCC amount. In vitro culture of human fibroblasts proved that the scaffold facilitated the proliferation of cells,confirming that it can function as a physical template with good cytocompatibility.Two kinds of BDEs, i.e. collagenchitosan/silicone membrane (BDE1) control and collagen-SCC/silicone membrane (BDE2),were used to repair skin scalds of Bama miniature pigs.The healing process of both BDEs was studied by macroscopic observation and HE staining.Immunohistochemical staining of VEGF and CD34 were performed to investigate the angiogenesis ability of these two kinds of BDEs.The results showed that compared to the BDE1,the BDE2 had a stronger ability to enhance the angiogenesis of the skin equivalent and the regeneration of the dermal layer.Transplantation of split- thickness skin graft was further carried out on the regenerated dermal layers.Results showed that only the scalds treated by the BDE2 had the ability to support the restoration of fullthickness skin.All these results demonstrate that the BDE2 with the SCC and collagen as the major component has better effect on accelerating the healing of scalds than that of the BDE1 with collagen and chitosan as the major component.One can also conclude that the sulfonated carboxymethyl chitosan,which is more structurally similar as heparin,should take the main role for the better repair results.
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发布时间：2021-03-19 - 摘要：Polystyrene/layered double hydroxide (PS/LDH) nanocomposites were prepared by in situ suspension polymerization of styrene in the presence of LDH intercalated with 4,4′-azobis(4-cyanovaleric acid) (ACP) groups and ACP/4-vinylbenzene sulfonate (VBS) composite groups,respectively.The morphological structure,thermal degradation behavior and rheological properties of PS/LDH nanocomposites were characterized by transmission electron microscopy (TEM),X-ray diffraction (XRD),thermogravimetric analysis (TGA) and capillary rheometry.It was found that ACP groups could successfully intercalate into the gallery of LDH individually or combined with VBS groups through the ionexchange reaction.It was evidenced by the XRD and TEM results that PS/LDH nanocomposites with higher exfoliation degree of LDH could be prepared by using of LDH intercalated with ACP/VBS composite groups.LDH nano-layers were dispersed in PS matrix after the meltprocessing.This was caused by the improved intercalation polymerization due to the initiation of intercalated ACP initiator.The TGA data evidenced that the thermal degradation temperatures of PS/LDH nanocomposites increased as the weight fraction of LDH increased, i.e, the thermal degradation temperatures corresponding to 10% weight loss were improved 25.4℃,34.4℃,47.4℃ and 52.9℃ when 1%,3%,5% and 7% LDH was incorporated into PS,respectively.It was also found that the melt flow rate of PS/LDH nanocomposites decreased as the weight fraction of LDH increased.
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发布时间：2021-03-19 - 摘要：The liquid-liquid phaseseparation (LLPS) behavior of poly(N-methyl methacrylimide)/poly(vinylidene fluoride) (PMMI/PVDF) blends was studied by using small angle laser light scattering (SALLS), and the timetemperature dependence of phase-separation behavior was discussed.According to examining the dependence of cloud points (Tc) on heating rate for PMMI/PVDF blends,it was found that Tc decreased as the temperature droped nonlinearly.When the heating rate was higher than 1.0 K/min,only the heating rate could affect the relative intensity I(t) ,and the difference of relaxation rate of polymer chain was difficult to be distinguished.Contrarily,both heating rate and relaxation rate of polymer chains could affect the cloud points of PMMI/PVDF blends at lower heating rates because there was enough time for the chain relaxation,and the different relaxation rates could result in the change of Tc.The cloud point curve of PMMI/PVDF blend was obtained at the heating rate of 1 K/min-1.The thermal behavior of PMMI/PVDF blends was measured by differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA).It was found that PMMI/PVDF exhibited a typical low critical solution temperature (LCST) behavior.Moreover,the temperature dependence of phase-separation kinetics for PMMI/PVDF blends followed the principle of time-temperature superposition (TTS) at the early phase-separation stage and may be described with a WLF-like equation.
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发布时间：2021-03-19 - 摘要：Atom transfer radical polymerization (ATRP) was applied to prepare an amphiphilic azobenzenecontaining ABA triblock copolymer PMAA-b-PMAZOCN-b-PMAA.In the presence of 4,4′-di(n-nonyl)-2,2′-bipyridine (bpy9) and CuBr (as the catalyst),the dibromo-initiator butylene di(2-bromoisobutyrate) was reacted with the azobenzene-containing monomer,6-［4-(4′-cyanophenylazo)phenoxy］hexyl methacrylate (MAZOCN),which resulted in the macroinitiator.The absolute molecular weight of the macroinitiator was obtained by GPC-SLS (gel permeation chromatographystatic light scattering) method.The dn/dc of the macroinitiator was predetermined as 0.257 mL/g by the refractometer.Then CuCl was used as the catalyst,and the macroinitiator further reacted with the tert-butyl methacrylate to obtain the triblock copolymer PtBMA-b-PMAZOCN-PtBMA as a precursor.From 1H-NMR,the polymerization of tBMA monomers initiated by the macro-initiator was proved by the presence of a rather strong resonance at δ=1.43 which is corresponding to the tert-butyl group.A single Gaussian peak in the GPC curves further proved the narrow polydispersity of the resultant precursor triblock copolymer.The absolute molecular weight of the triblock copolymer was obtained by combination of the segement molar ratio determined from the characteristic 1H-NMR peaks and the absolute molecular weight of the macroinitiator.In the final step,the tert-butyl groups were removed by the selective hydrolysis reaction with trifluoroacetic acid at room temperature. 1H-NMR analyses proved that most of the tert-butyl groups were hydrolyzed (conversion 95%),while the ester groups in the azo blocks were retained.These monomers and polymers were then studied with PLM (polarized light microscopy) and DSC (differential scanning calorimetry).The monomer,macro-initiator and the precursor triblock copolymer are all own smectic phase in the liquid crystalline region,while no characteristic liquid crystalline texture could be observed for the amphiphilic triblock copolymers.It is possibly because that,the presence of H-bonds between carboxyl groups hindered the development of the liquid crystalline phase.The amphiphilic ABA triblock copolymer possessed hydrophilic blocks in the outer part and the hydrophobic block in the central part.The vesicular aggregates of the polymer were obtained by gradually adding water,which is the good solvent of the hydrophilic block and the poor solvent of the azobenzene-containing liquid crystalline block,into the stirring THF solution of the amphiphilic copolymer.When the water content was more than 50% volume ratio,an excessive amount of water was added to freeze the assembly of the copolymer.THF was removed from the mixed solvent by dialyzed against ultrapure water for days.The TEM (transmission electron microscopy) observation showed that the amphiphilic block copolymer self-assembled into vesicular aggregates with average diameters from 300 to 500 nm.By using a high-pressure mercury lamp as the light source,the vesicular aggregates transform to the colloidal spheres when irradiated with the ultraviolet light in the solid state.
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发布时间：2021-03-19 - 摘要：Surface-grafted or cross-linked polystyrene(PS)/CaCO3 composite nanopartic les with nanometer CaCO3 as the core were synthesized by in situ emulsion polymerization.Subsequently,PS hollow nano-spheres were prepared by etching the core with dilute hydrochloric acid.The effects of the type and amount of emulsifier,the addition method of initiator and the feeding interval on emulsion stability,the yield and grafting efficiency were investigated.Composition and morphology of composite nanoparticles before and after etching were characterized by TGA,FT-IR and TEM.The results show that cationic emulsifier is in favor of the stability of emulsion system,and a higher yield and grafting efficiency can be achieved when using 3.7% ～ 5.5% cetyltrimethylammonium bromide (CTAB) as the emulsifier.With the amount of CTAB increased,the size of composite nanoparticles becomes smaller and the size distribution becomes broader.2,2′-azobisisobatyronitrile (AIBN),the initiator,should avoid ultrasonic treatment along with monomers and CaCO3 particles,which may induce irreversible agglomeration.With the feeding interval prolonged,the yield and grafting efficiency decrease,and onepot method contributes to obtain composite nanoparticles with higher yield and grafting efficiency (or cross-linked degree).Although hollow particles can be prepared from either surface-grafted or cross-linked PS/CaCO3 composite particles by etching,the latter with cross-linked polymer shell have rather better size and shape stability and can retain their sphere shape after etching.
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发布时间：2021-03-19 - 摘要：A novel optically active polyelectrolyte poly［ethylene-alt-R-N-(1-phenylethyl)maleamic acid］ was synthesized from poly(ethylene-alt-maleic anhydride) and R-(+)-α-phenylethylamine at 1∶1 molar ratios in the presence of toluene,over a period of 5 h at 100℃,leading to a total yield of product up to 93%.The product was characterized by FT-IR,UV-Vis, 1H-NMR and polarimetric analysis.In the FT-IR spectrum of poly［ethylene-alt-R-N-(1-phenylethyl)maleamic acid］,the peaks at 1851 and 1784 cm-1 corresponding to the CO= stretching and the peaks at 1219,964 and 921 cm-1 of the C—O—C band absorption of the cyclic anhydride disappeared,respectively,whereas three peaks at 1643,1550 cm-1 and 1205 cm-1 corresponding to the amide bond were observed.The UV-Vis absorption due to the π→π* transition of the polymer backbone was observed at λ=194, 210 and 257 nm.The 1H-NMR spectrum of poly［ethylene-alt-R-N-(1-phenylethyl)maleamic acid］ showed three peaks.The peaks at δ=7.3～7.5 representing the chemical shift of H for phenyl ring,2.0～2.2 representing the chemical shift of H for groups of CH—CO and N—CH and 1.0～1.3 representing the chemical shift of H for —CH2— groups and —CH3 groups indicated the molecular structure of poly［ethylene-alt-R-N-(1-phenylethyl) maleamic acid］.The specific rotatory power of the new optically active polymer was +82.5°.Poly［ethylene-alt-R-N-(1-phenylethyl)maleamic acid］/poly(diallyldimethylammonium chloride) ultra-thin films were fabricated with electrostatic layer-by-layer self-assembly method onto a glass substrate and the buildup of film was monitored with UV-Vis spectrophotometry.UV-Vis absorbance at λ=210 nm revealed that the assembly amount of multilayer grew exponentially with the number of bilayers.
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发布时间：2021-03-19 - 摘要：Polypropylene(PP)/polystyrene(PS)/clay composites were prepared by melt blending at 160℃ to investigate the dispersion of clay in the immiscible blend system.The results show that the preferential intercalation phenomenon of clay occur in the immiscible PP/PS blend,as evidenced by wide angle Xray diffraction (XRD) and transmission electron microscopy (TEM).Independing on the proportion of PS components and its feeding modes,PS chains intercalate preferentially into clay layers.PP and PS components show different dependence of melt viscosity on temperature,as confirmed by capillary rheological analysis and advanced rheological expansion system (ARES) measurements.PS has higher viscous flow activation energy,which means its melt viscosity is more sensitive to the processing temperature.Based on different dependence of melt viscosity on temperature between PP and PS,the effects of melt viscosity on the preferential intercalation behavior of clay were investigated via changing the processing temperatures.The clay platelets gradually transferred from PS phase to PP phase with increasing processing temperature.The results combining TEM and ARES suggest that the preferential intercalation behavior of clay is determined by the difference between the viscosity of the two components.Furthermore,the higher viscosity of component,the stronger shear stress during the compounding process,it consequently results in stronger capabilities of intercalation.
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发布时间：2021-03-19 - 摘要：It is very important to manipulate the switch temperature,mechanical properties and degradation rate of biodegradable shape memory polymers(BSMPs) from the viewpoint of practical applications.This can be realized through molecular design of the microstructure of the building blocks of BSMPs.In this study,hydroxy-telechelic poly(L-lactide-co-glycolide) (PLLG-diol) and poly(ε-caprolactone-co-glycolide) (PCG-diol) copolymers with adjustable composition,molecular weight and thermal transition temperature were synthesized via ring opening copolymerization of L-lactide/glycolide and ε-caprolactone/glycolide,respectively.Biodegradable segmented poly(esterurethane)s were then synthesized via reaction with diisocyanate using them as hard and soft segments,respectively.Their molecular weight distribution,thermal transition and thermal induced shape memory behaviors were studied with GPC,DSC and thermomechanical characterization,respectively.Segmented poly(ester-urethane)s exhibit excellent shape memory properties,with strain fixity rate of 98%～99.5% and strain recovery rate of 93%～98.5%.The strain fixity rate is independent of the composition and molecular weight of the segments,but the strain recovery rate increases with increasing the molecular weight or decreasing the GA content in the segments.With controlling the transition temperature of the soft segments,the shape recovery does not occur at body temperature but takes place at a little higher temperature in the range of 40～50℃.This character is very desired for and beneficial to clinical applications.The shape recovery speed can be adjusted by the environmental temperature or the heating rate.
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发布时间：2021-03-19 - 摘要：In order to understand the coarsening of microdomains in symmetric diblock copolymers at the late stage,a model for block copolymers is proposed.By incorporating the self consistent field theory with the free energy approach Lattice Boltzmann model,hydrodynamic interactions can be considered.Compared with models based on Ginzburg-Landau free energy,this model does not employ phenomenological free energies to describe systems.The model is verified by comparing the simulation results obtained using this method with those of a dynamical version of the self consistent mean field theory.After that,the growth exponents of the characteristic domain size for symmetric block copolymers at late stage are studied.It is found that the viscosity of the system affects the growth exponents greatly,although the growth exponents are all less than 1/3.Furthermore,the relations between the growth exponent,the interaction parameter and the chain length are studied.The rescaled simulation results show that the dependence of growth exponent on the interaction parameter is trivial; however,the length of the polymer chain may lead to the change of the growth exponent.This conclusion is different from that based on a free energy function given by the Ginzburg Landau expression.This difference may come from the additional correlation considered in the self consistent field theory of our model.Nevertheless,the chain length effect on the growth exponent is little compared with that of the fluid viscosity.
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发布时间：2021-03-19 - 摘要：Nowadays,synthetic optically active polymers are of great interests,since they might mimic the fascinating functions of naturally occurring polymers,such as nucleic acid,protein,and polysaccharide,and leading extensive studies being conducted on their synthesis,conformations and functions.In this publication,Optically active diblock copolymers poly(ethylene golycol) monomethyl ether-b-poly(N-methacryloyl L-leucine methyl ester)s (MPEG-b-PMALM)s,with different mole ratios for the two blocks and narrow molecular weight distribution,were synthesized via atom transfer radical polymerization (ATRP),using Bromine terminated poly(ethylene glycol) monomethyl ether (MPEGBr) as macroinitiator and tris［(2-dimethylamino)ethyl］amine (Me6TREN)/CuBr as catalytic system.The chemical structure and the mole ratio of the two blocks were verified by 1H-NMR. The molecular polydispersity,as evaluated from SEC,as well as the bromine content in the prepared block copolymer,as analyzed from anion chromatography,indicate that the reaction is followed the mechanism of ATRP.Thermogravimetry analysis (TGA),and differential scanning calorimetry (DSC) were used to evaluate the thermal properties of the prepared polymers.The specific rotation of the prepared polymers reversed against that of the monomer, and its absolute value was obviously larger than that of the monomer.It was found that the absolute value increased with the increase of weight ratio of PMALM blocks in the prepared polymers.The random conformation of the copolymer was verified by CD spectra,and it was found that the optical activity of the block copolymer was promoted with the increase of the ratio of PMALM block to MPEG block in the block copolymers.
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发布时间：2021-03-19 - 摘要：Water borne anti-corrosion coating was prepared from conductive polyaniline (cPANI)/polysilsesquioxane hybrids,where electrostatic interaction was introduced into the hybrids by carboxyl group capable of interacting with positively charged nitrogen atom in cPANI backbone.In 3.5 wt% NaCl media,the corrosion potential of the electrostaticinteraction hybrid coating containing 11 wt% cPANI showed nearly 200 mV positive than that of pure inorganic polysilsesquioxane coated cold rolled steel (CRS),with corrosion current dropping by 5 times from 13.4 A to 2.4 A,indicating that the cPANI hybrids coated CRS became more noble against the electrochemical corrosion.The Niquist plots indicated that electrostaticinteraction hybrid coating with 11 wt% cPANI displayed impedance one order of magnitude higher than that of pure inorganic coating,moreover,the impedance of the cPANI/polysilsesquioxane film maintained nearly constant after 10 days of immersion in saline media,whereas that of pure inorganic coating decreased one order of magnitude from the initial value,suggesting much improved anticorrosion performance using the electrostatic-interaction cPANI hybrids.Morphology study indicated that the cPANI was distributed in a more homogeneous way in electrostatic-interaction cPANI/polysilsesquioxane hybrids than in common cPANI/polysilsesquioxane hybrids,leading to much better anti-corrosion performance than common cPANI/polysilsesquioxane hybrids.
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发布时间：2021-03-19 - 摘要：Synthesis of biobased and biodegradable polymers from renewable biomass has attracted much attention in recent years.Levulinic acid has been deemed as a platform chemical from non-food stuff biomass,and some of its derivatives are starting materials for new polymers.In this paper,poly(5-hydroxylevulinic acid-co-L-lactic acid) (PHLL) was synthesized via melt copolycondensation of 5-hydroxylevulinic acid (5-HLA) and L-lactic acid (LLA) and characterized with GPC,X-ray, 1H-NMR,FTIR and DSC.The results showed that the copolymers had interesting olefinic ether branch structures formed via etherification between carbonyl of 5-HLA and hydroxyl in LLA.The copolymer was amorphous in a broad composition range and had high glass transition temperature (Tg) ranging from 54.6℃ to 91.4℃,which increased with the increase of 5-HLA content due to the existence of hydrogen bonds in the 5-HLA moiety of the copolymer.The hydrolytic degradation behavior in deionized water showed that PHLL readily degraded hydrolytically in aqueous medium,and the degradation rate depended on its microstructure.The amorphous LLA moiety degraded faster than the 5HLA counterpart.
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发布时间：2021-03-19
Research Article
- 摘要：Surface contact disinfecting technique is a newly developed method for water sterilization.To prepare the antibacterial material having special ability and deeply study the antibacterial process and mechanism of surface contact disinfectant containing quaternary ammonium salts,the antibacterial and temperature responsive functional copolymer (poly(DMAE-BC-co-NIPAAm)) was introduced onto the surface of polyethylene (PE) films by UV-induced photografting method.IR showed that the copolymer of DMAE-BC and NIPAAm were successfully grafted onto the film.The surface of photo-grafted films was investigated through water contact angle (CA) measurements.It was found that the hydrophobicity of the co-grafted film increased with the temperature increasing from 20℃ to 40℃.The antibacterial properties of the co-grafted film were mainly investigated using -Escherichia coli (E.coli),a kind of gramnegative bacteria,as model bacterium.First,the desorption of bacteria cells adsorbed on the surface co-grafted films was measured.In the 1 mol/L NaCl solution,lower than 35% bacteria cells was rinsed out from grafted films because the positive change on the antibacterial film surface was shielded,and the desorption rate of E.coli cells decreased with increasing temperature from 20℃ to 40℃.The cell-lysis action to bacteria cell was further investigated by measuring the activity of β-galactosidase.The antibacterial film was put into the cell suspension containing O-nitraphenyl β-D-galactopyranoside (ONPG),and the changes of absorption at 400 nm with time were measured.The fact indicated that the co-grafted film disrupted the cell inner membrane,and the destroying action to the cell increased with increasing temperature from 20℃ to 40℃.The co-grafted film was believed to have both the antibacterial ability and temperature sensitivity,and the antibacterial ability changed with the temperature.The experimental results clearly showed the hydrophobic action played an important effect in both the desorption and cell-lysis steps.
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发布时间：2021-03-19 - 摘要：Polypropylene (PP)/1,4-bis(3-tetradecylimidiazolium-1-yl)butane bromide (Br［C14im］(CH2)4［C14im］Br) blends were prepared via melting blending,and then the structure and properties of the blend were characterised and tested.Results of testing indicate that Br［C14im］(CH2)4［C14im］Br could have a heterogeneous nucleating effect in the PP matrix.Moreover,PP was readily to form α crystal in the PP crystallizing process with the help of Br［C14im］(CH2)4［C14im］Br.XRD data show the crystallizing process of PP could be affected by Br［C14im］(CH2)4［C14im］Br,and thus decreased the crystallinity of PP.DSC results show the melting point and the crystallization temperature of PP/Br［C14im］(CH2)4［C14im］Br blends was close to that of neat PP,this maybe due to the good compatibility of PP to Br［C14im］(CH2)4［C14im］Br with long alkyl chains.In addition,the presence of Br［C14im］(CH2)4［C14im］Br could improve the antistatic properties of PP apparently,and the surface resistivity of the PP was decreased to 8.97×109 Ω cm when the content of Br［C14im］(CH2)4［C14im］Br in the blends was about 3 phr.As for the mechanical properties,the tensile strength decreased while the impact strength of materials presented the opposite results with Br［C14im］(CH2)4［C14im］Br incorporated into it.DMA results show the glass transition (Tg) of PP also decreases when 3 phr Br［C14im］(CH2)4［C14im］Br exists in its matrix.Therefore,Br［C14im］(CH2)4［C14im］Br has the plasticized effect on the PP matrix in our experiments.
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发布时间：2021-03-19
Research Bulletin
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