最新刊期
卷 ， 期 6 ， 2013
- 摘要：In last century,poly(aryl ether ketone) resins were developed as super engineering plastics applied to a wide range of fields,such as high-tech defense industry,weapons and equipment,aerospace,electronics,automobiles,machinery,oil industry,nuclear energy and physical therapy and health application.In general,these polymers were prepared by A2 + B2-type nucleophilic polycondensation reaction procedure from bisphenol monomer and difluoride monomer.Molecular structure of poly(aryl ether ketone) more effect on the polymer performance.Two kinds of poly(aryl ether ketone)s which are semi-crystalline polymer and amorphous polymer are formed by changing molecular structure.Semi-crystalline poly ( aryl ether ketone)s are constructed by regular three unit structure of ethers,ketones and benzene.Amorphous poly(aryl ether ketone)s contain pendant groups or non-regular structure,which destroy the crystalline structure of the polymer.Semi-crystalline poly(aryl ether ketone)s having excellent heat resistance,chemical stability are generally used as structured materials,however amorphous poly(aryl ether ketone)s have good processing properties and become a class of excellent functional material by introducing special functional groups.Base on the relationship between the structure and properties of poly(aryl ether ketone),this article introduced several types of poly(aryl ether ketone ) s (PAEKs) currently developed,including their development and synthetic routes,investigated the relationship between structure and performance,made an overview of recent advances in functional PAEKs,and finally outlook the trends in applications of PAEKs.关键词：Poly(arylene ether ketone)s;High-performance polymer;Structure;Property
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发布时间：2021-03-19 - 摘要：Custom-designed biomedical polymer materials can be fabricated rapidly and precisely by 3-dimensional (3D) printing technology according to the requirements of patients with various diseases.In addition,the microscopic structure of the materials can be controlled during the printing process.Therefore,this novel type of technology has unique advantages in the preparation of next generation of biomedical polymer scaffolds.In recent years,the development of biomedical polymer materials by using 3D printing technology has received increasing attention.Various biocompatible polymers have been used to construct 3D scaffolds via 3D printing,and the printed polymeric scaffolds have been tested for in vitro cell culture,soft tissues repair or hard tissue repair in animal models.This review emphasizes recent advances in the development of biomedical polymer materials made by 3D printing technology,and some future applications and challenges of the technology are discussed.关键词：3D printing technology;Custom-designed;Biomedical polymers;Tissue engineering
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发布时间：2021-03-19 - 摘要：Since the polymer prodrug concept was first proposed in 1970s,polymer pharmacy,as the interdiscipline of polymer science,material science,nano-science,pharmacy,clinical medicine and analysis science,has been quietly born along with the development of nanotechnology.In this paper,an overview of the progress of polymer drugs in pharmacochemistry,pharmaceutics,and pharmacodynamics is provided; the connection and distinction between polymer drugs and small molecule drugs in pharmacology and pharmacokinetics are outlined; the bottleneck tissues in pharmacodynamics and pharmacokinetics of polymer drugs are pointed out,especially the three states of polymer drugs and the transformation of the nano-particle drug through macromolecular drug to small molecular drug; the multiple obstacles on the pathway of polymer drugs such as capillary vessel wall,extracellular substance,cellular wall,etc.,are analyzed; the competition between the physiological targeting of human organs and the EPR effect of cancerous tissues is elucidated; the possible contribution and merits of polymer drugs in drug targeting delivery and in reversion of drug resistance are pointed out; the necessity of developing the related analytical methods is emphasized; and an urgent expectation is expressed that scientists and experts working in polymer science and in pharmacology cooperate with each other sincerely and effectively to promote the innovation and development in polymer pharmacy and polymer drug industry in our country.关键词：Polymer drugs;Polymer prodrug;Polymer pharmacy;Polymer pharmacology;Polymer pharmacokinetics;Polymer pharmacodynamics
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发布时间：2021-03-19
Reviews
- 摘要：The solution behavior of a newly developed comb-like polymer-based dispersant was investigated by laser light scattering (LLS) with a focus on the conformation of the chain in solution.By static light scattering,reasonable parameters,such as weight-averaged molecular weight (Mw) and mean square radius of gyration (Rg2) were obtained.Furthermore,apparent intensity-weighted hydrodynamic radius distribution and its dependence on the concentration and scattering angle were investigated by dynamic light scattering.By comparing the results from LLS with the popular Gay-Raphae model of comb-like polymers,it is suggested that there might be aggregation behavior and the current comb-like polymers exist in solution as micellar aggregates.关键词：Comb-like polymer;High performance water-reducing admixture;Light Scattering;Cement;Solution conformation
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发布时间：2021-03-19 - 摘要：Poly(lactide-co-glycolide) (PLGA) porous scaffolds were prepared via room-temperature molding/particle leaching method,and in vitro degradations of those porous scaffolds were examined in phosphate buffer saline (PBS) solution at 37 ℃ for 24 weeks.Each PLGA85/15 scaffold of porosity a bit above 90% and weight about 50 mg was immersed in 10 mL PBS.The degradation media were replaced by fresh ones weekly.Part of degradation media were collected at series of degradation time points,and then added into the culture medium of mesenchymal stem cells (MSCs).Cell viability and osteogenic differentiation were detected via lactate dehydrogenase assay,Live/Dead staining,3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay,alkaline phosphatase staining and quantification.The results indicated that molecular weight of remaining PLGA,and weight,dimension,pore size,and interpore connectivity of scaffolds changed with different degrees.The degradation media at all of degradation times up to 24 weeks exhibited no severe cytotoxicity,and no significant negative influences on viability,proliferation and osteogenic differentiation of MSC were observed under the present conditions and examined period.关键词：Polyester;Degradation;Mesenchymal stem cells;Biocompatibility
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发布时间：2021-03-19 - 摘要：Poly(styrene-alt-maleic anhydride)(SMA) was prepared by solution polymerization of styrene(St) and (MAH).SMA was saponified with KOH to get SMAA,and the resulting SMAA then served as polymeric surfactant for the suspension polymerization of St.The influence of ionization degree of SMAA,rotation speed and weight ratio of St to water on the size and morphology of the obtained PS particles has been studied in detail by optical microscopy and SEM.When ionization degree of the SMAA was 50%,the SMAA was partially saponified product containing both carboxylic acid and carboxylate groups.By using this SMAA as polymeric surfactant,spindle PS particles were prepared at high ratios of St to water(3.0∶3.5~3.0∶4.5) and medium rotation speeds.At optimum reaction conditions,the average size of the particles was 6.8 mm in length,1.4 mm in width,0.5 mm in thickness and the ratio of length to width was 5.0.With increasing rotation speed,the size of the particles decreased gradually and the ratio of length to width became higher.Based on these experiment results,the formation mechanism of the PS nonspherical particles by suspension polymerization in the presence of SMAA was preliminarily proposed.关键词：Poly(styrene-alt-maleic anhydride);Polymeric surfactant;Suspension polymerization;Spindle polymer particles
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发布时间：2021-03-19 - 摘要：Two alkynyl-functionalized mannoses (A-Man and A-DiMan) and 2-(2-(2-azido-ethoxy)-ethoxy)-ethyl amine (N3-TEG-NH2) were synthesized.N3-TEG-NH2 was used to initiate the ring-opening polymerization of N-benzyloxycarbonyl-L-lysine N-carboxyanhydride (Lys(Z)-NCA) to obtain two azido-terminated polylysines with different degree of polymerization,N3-P(Lys(Z))15 and N3-P(Lys(Z))35.Click reactions of these two polymers with A-Man and A-DiMan produced four mannose-terminated polylysines,M-P(Lys(Z))15, M-P(Lys(Z))35, DiM-P(Lys(Z))15 and DiM-P(Lys(Z))35.The structure of these polymers was characterized by a range of means including GPC,NMR and FTIR.These polymers belong to amphiphilic diblock copolymers with P(Lys(Z)) as the hydrophobic chain and the mannose-containing moieties as the hydrophilic part,and their aggregation behavior in water were investigated.The polymers were first dissolved in THF/DMF (4/1,V/V),and then water was added slowly to induce the self-assembly of polymers.After removing the orgnic solvents by dialysis,the morphologies formed were observed by transmission electron microscopy (TEM).TEM results revealed that vesicles were the main morphologies for the two polymers with shorter P(Lys(Z)) chains (M-P(Lys(Z))15 and DiM-P(Lys(Z))15),while the two polymers with longer P(Lys(Z)) chains (M-P(Lys(Z))35 and DiM-P(Lys(Z))35) tended to form micelle-like aggregates.This phenomenon was different from the common self-assembly behavior of amphiphilic diblock copolymers in water,which was attributed to the easy -helix formation of polymers containing longer P(Lys(Z)) chains.关键词：Mannose;Polylysine;Glycopeptide;Vesicle;Micelle
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发布时间：2021-03-19 - 摘要：A new method was developed to fabricate polymeric microspheres which were composed of homogeneous nanofibers by means of the combination of heterogeneous nucleation and controlled hydrolysis.According to the role of heterogeneous nucleation of multimethyl-benzilidene sorbitol (TM6) and its influences on the crystalline morphology of poly(butylene adipate)(PBA),the PBA microspheres were first fabricated by means of single emulsion solvent evaporation (O/W) or double emulsion solvent evaporation (W/O/W),and then the influences of the nucleating agent TM6 on the morphological change of microspheres in the course of enzymatic degradation were studied.The results indicated that the PBA microspheres with porous structure were fabricated via the W/O/W method.The porous structure of microspheres is favorable for the diffusion of lipase buffer solution into the porous inner of microspheres,leading to the homogenous hydrolysis of PBA chains in microspheres,and finally resulting in the microspheres with nanofibrous structures.By means of W/O/W method,the PBA microspheres with homogeneous nanofibers in whole microspheres were fabricated when 3 wt% TM6 was added in PBA solution and the microspheres were degraded in lipase buffer solution for 5 h.The cell experiments revealed that the nanofibrous structure can greatly improve the adhesion,spread and in-growth of MG-63 cells on microspheres.These microspheres composed of nanofibers show great potentials for large-scaled cell proliferation in bioreactors.关键词：Polymeric microspheres;Nanofibers;Heterogeneous nucleation;Enzymatic degradation
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发布时间：2021-03-19 - 摘要：Phosphorus has a structure with five coordination,this compound is easy to form enantiomers and can hardly be separated.In this paper,four propargylphosphonamide monomers ［ HCCCH2 NH( P=O )-R1R2.Monomer 1 :R1=OPh,R2=NC4H7COOCH3;monomer 2 :R1=OPh,R2=NC4H7COOCH2CH3;monomer 3 :R1=OPh,R2=NC4H7COOC(CH3)3 and monomer 4 :R1=Ph,R2=NC4H7COOC(CH3)3］ were designed and synthesized.1H-NMR and 31 P-NMR show that monomer 1 can only form enantiomer and cannot be separated.But monomer 2 ,monomer 3 and monomer 4 can be separated by resolving agent to form P-chiral diastereomeric monomers.Polymerization was carried out with (nbd)Rh+［6-C6H5B--(C6H5)3］ as catalyst in CHCl3 giving four polymers with moderate molecular weights (Mn) (0.4104~0.7104) and Mw/Mn (1.26~1.98) by GPC,two factors (the pendent group and temperature) were observed to affect the helix structure of polymers.The optical activity and secondary structure of the polymers were characterized by specific rotations (［］D),circular dichroism (CD) spectra and UV-Vis.It shows that the polymers have good optical activity and can form a single direction of the helical conformation.It was found that the secondary structure stability of the copolymer is better than homopolymers in different mixed solvents,when the methanol quantity was up to 50%,CD spectra of poly 3 and poly4 change largely,which shows methanol broke the hydrogen bond between phosphorus-oxygen bond and nitrogen-hydrogen bond.关键词：Helical polymer;Chiral phosphorus;Optical activity;Polyacetylene;Enantiomer
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发布时间：2021-03-19 - 摘要：A new linear chiral polymer ligand was synthesized by the polymerization of (S)-5,5'-dibromo-6,6'-di(4-trifluoromethylphenyl)-2,2'-binaphthol (S-M-1) with (S)-5,5'-diethynyl-6,6'-dibutyl-2,2'-dibutoxy-1,1'-binaphthyl (S-M-2) via Pd-catalyzed Sonogashira reaction. The application of the chiral polymer ligand in the asymmetric addition of Et2Zn to various aromatic aldehydes had been studied. The results showed that this kind of soluble chiral polybinaphthols ligand in combination with Ti(OiPr)4 could exhibit good reactivity and enantioselectivity for the asymmetric addition of Et2Zn to aromatic aldehydes. Moreover, the chiral polymer ligand showed superior enantioselectivity over the model compound S-1 and could keep similar reactivity as well as enantioselectivity after ten recycles.关键词：(S)-1,1'-bi-2-naphthol;Sonogashira coupling;Asymmetric addition
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发布时间：2021-03-19 - 摘要：Three one-handed helical poly(phenylacetylene) derivatives bearing L-amino acid ethyl ester pendants,PPA-S-Phe,PPA-S-Leu and PPA-A-Leu were respectively synthesized by the polymerization of the corresponding monomers using Rh(nbd)BPh4 as a catalyst,and their chiral recognition abilities for seven racemates were evaluated as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) after coating them on silica gel.The difference between PPA-S-Phe and PPA-S-Leu is the chiral pendants.The chiral pendant of PPA-S-Phe is L-phenylalanine ethyl ester,while that of PPA-S-Leu is L-leucine ethyl ester.The difference between PPA-S-Leu and PPA-A-Leu is the linkage groups between polymer main chains and chiral pendants.The linkage of PPA-S-Leu is sulphonamide group,while that of PPA-A-Leu is amide group.PPA-S-Phe,PPA-S-Leu and PPA-A-Leu possess their characteristic helical conformation and show their characteristic chiral recognition depending on the chiral pendants and the linkage groups.When linkage is a sulphonamide group,PPA-S-Leu with L-leucine ethyl ester pendants shows higher chiral recognition abilities than PPA-S-Phe with L-phenylalanine ethyl ester pendants.When chiral pendant is L-leucine ethyl ester,PPA-A-Leu with amide linkage shows higher chiral recognition abilities than PPA-S-Leu with sulphonamide linkage.It is concluded that the linkage groups play an important role in chiral recognition as well as the chiral pendants.关键词：Poly(phenylacetylene) derivatives;Helical conformation;Chiral pendants;Linkage group;High-performance liquid chromatography (HPLC);Chiral recognition
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发布时间：2021-03-19
Research Article
- 摘要：A photo-responsive amphiphilic triblock copolymer has been synthesized.The hydrophobic segment of copolymer was prepared by ring-opening polymerization of p-dioxanone(PDO) using 4,4'-bis-(hydroxyethylether) azobenzene (BHEAZO) as an initiator and stannous 2-ethylhexanoate ［Sn(Oct)2］ as a catalyst.The hydroxyl terminated poly(p-dioxanone)(PPDO) precursors were then coupling-reacted with the carboxyl group terminated hydroxymethyl polyethylene glycol(mPEG-COOH) to give the mPEG-BHEAZO-PPDO-mPEG triblock copolymer.The photo-responsive behavior of the copolymer was studied by UV-Vis spectroscopy,dynamic laser scattering (DLS) and transmission electron microscopy (TEM).The configurational change of the azobenzene group contained in the copolymer nano-aggregate was investigated by the UV-Vis spectroscopy.The absorbance of the nano-aggregate aqueous solution increased with the growth of the irradiation time.The size of nano-aggregate particle and particle size distribution after exposure to light with different wavelengths were measured by DLS.The size of the copolymer nano-aggregate after exposure to 450 nm light was getting bigger than that to 365 nm,and the size distribution was getting wider at the same time.The TEM images of the nano-aggregate aqueous solution were consistent with the DLS results.According to the analyses above,a hypothetic mechanism was proposed for explaining the changes of the nano-aggregates after exposure to lights with different wavelengths.A single nano-aggregate particle easily tended to aggregate with the particles nearby since the trans configuration of azobenzene groups in the copolymer was more likely to form a stable electron delocalization state of low level,which could lead to a stonger - stacking effect.关键词：Amphiphilic block copolymers;Azobenzene;Poly(p-dioxanone);Photo-responsive
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发布时间：2021-03-19
Research Bulletin
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