JOURNAL OF APPLIED POLYMER SCIENCE
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2015
·Vol. 132
·期 27
·
IF 1.768
Lijing Teng,Wangyan Nie,Yifeng Zhou,Linyong Song,Pengpeng Chen
The purpose of this study was to investigate the suitability of a six-arm star-shaped poly( l -lactide)s (s-PLLA) as controlled drug carriers for hydrophobic drug molecules. First, s-PLLA was synthesized by ring-opening polymerization of l -lactide using sorbitol as initiator and stannous octoate as catalyst. The structure and molecular weight ( M w ) of s-PLLA was characterized with 1 H NMR, 13 C NMR, and GPC. Second, rifampicin (RIF) used as a model drug was encapsulated within the microspheres of s-PLLA via oil-in-water emulsion/solvent evaporation technique. The morphology, drug encapsulation efficiency (EE), and in vitro release behavior of the prepared microspheres were studied in details. Results indicated that the average diameters of s-PLLA microspheres can be controlled between 8 and 20 µm by varying the copolymer's concentration or M w . The EE of RIF was mainly determined by the concentration of s-PLLA. The in vitro study showed that the burst release behavior can be depressed by increasing the M w of the s-PLLA. Present work suggests that the synthesized s-PLLA could be used as a new material for drug delivery. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42213.
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Zuojia Xi,Xubiao Zhang,Chaohe Yang,Jun Xu
In the global energy landscape, the development of desert oil in Africa has increased the diversity of world oil supply and helped maintain the balance of the global energy market. However, wax precipitation and asphaltene deposition cause numerous challenges during the recovery and pipeline transportation of African crude oil. Traditional linear polymer additives often have limited wax-modifying and asphaltene-dispersing efficiency. In this work, linear poly(octadecyl acrylate-styrene) (POA-St) and a series of star POA-St copolymers with different arm numbers (3, 4, and 6) were synthesized through reversibly additive fragment chain transfer polymerization. The effects of the linear and star POA-St on the wax precipitating properties, pour point, rheology, and asphaltene stability of African waxy crude oil were studied in detail. The star POA-St copolymers show superior performance compared with linear polymers in inhibiting wax crystal formation, improving crude oil rheology, and stabilizing asphaltene. Increasing the arm number of star POA-St greatly improves its performance. Star POA-St-6 reduces the wax appearance temperature of the crude oil from 53.7°C to 51.1°C. At 20°C, the addition of the star POA-St-6 reduces the pour point of crude oil from 30°C to 21°C, and the viscosity and yield stress decrease by 74% and 55.2%, respectively. In addition, star POA-St-6 increases the initial precipitation points of asphaltene from 44.3% to 57.1%, showing a splendid asphaltene inhibiting efficiency. We speculate that the star POA-St stabilizes asphaltene aggregates among its arms and changes the wax crystal morphology through co-crystallization and nucleation effects, thereby exhibiting good performance. These findings provide prospective insights and avenues for the structural optimization and innovation of a new type of pour point depressant.
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DOI
高影响因子
POLYMERS & POLYMER COMPOSITES
·
2015
·
IF 0.271
Xiaojing Zhang,Chong Li,Yuelei Hu,Jiashu Sun,Shaoming Fang
In this paper, a series of star-shaped poly(lactide-co-glycolide)s (sPLGA) with different block ratios were prepared by the ring-opening copolymerization of D,L-lactide (LA) and glycolide (GA) with multi-hydroxyl polyhedral oligomeric silsesquioxane core as an initiator and tin (II) 2-ethylhexanoate (Sn(Oct)2) as the catalyst. The products were characterized by NMR, FT-IR, GPC, XRD, DSC, TGA and viscosity measurements. The results show that the contents of PLA and PGA segments in sPLGA can be controlled by the feed ratios of the copolymerization. The glass transition temperature and crystallinity of sPLGA decrease and the crystalline sPLGA becomes amorphous with increasing the molar feed ratio between GA and LA from 10:90 to 50:50. The drug-loaded sPLGA microspheres were prepared by an emulsion solvent evaporation method. The morphology and the drug release property were investigated by SEM, dynamic light scattering (DLS) and ultraviolet spectrophotometry (UV). The results indicate that the sPLGA80 microsphere surface was smooth and the mean diameter was about 1.27μm. The sPLGA80 microspheres showed good drug loading and release properties.
研究领域:
材料科学
·
药剂学
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2015
·
IF 2.752
Yinwen Li,Huilong Guo,Jian Zheng,Jianqun Gan,Kun Wu,Mangeng Lu
Star polymers (CD-POEGMAs and CD-PNIPAMs), and pseudo-graft polymer (PADMA-(CD-POEGMAs) x ) formed from PADMA with adamantyl(Ad) pendants and CD-POEGMAs by host–guest inclusion complexation were prepared and characterized. This work compared the thermoresponsive and self-assembly mechanisms of the POEGMAs as branches to that of PNIPAMs branched cyclodextrin cored star polymers. In contrast to CD-PNIPAMs which behaved abrupt and intensive dehydration process near its LCST, CD-POEGMAs exhibited thermally induced aggregation process with consecutive conformation changes during the temperature increase process, and gradually self-assembled into cyclodextrin centered aggregates with hydrophobic methacrylate backbone and dehydrated POEGMAs side chains. Moreover, this work provided a supramolecular method controlling and adjusting the thermoresponsive properties of pseudo-graft PADMA-(CD-POEGMAs) x formed from CD-POEGMAs and PADMA via inclusion complexation, which underwent a reversible thermally induced transition from micelle to nano-aggregates. Pseudo-graft PADMA-(CD-POEGMAs) x behaved gradually conformation changes as temperature rising, and self-assembled into aggregates with hydrophobic methacrylate backbone, residual Ads, and dehydrated POEGMAs side chains.
研究领域:
高分子化学
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材料科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2019
·
IF 7.015
Zhuliu Xiao,Binghua Zhou,Jirong Wang,Cai Zuo,Dan He,Xiaolin Xie,Zhigang Xue
Tailor-made star polymers comprised of cross-linked cores containing polymeric pseudo-crown ether cavities and linear poly(ethylene oxide) (PEO) arms are designed via cation template-assisted cyclopolymerization. The pseudo-crown ether cavities in cross-linked cores can coordinate with alkali metal cations and offer more cation diffusion channels. Moreover, the functional linear PEO arms are beneficial to the conductivity of cations and increase the compatibility with the PEO matrix. By selecting monomers with different chain lengths and cation templates, the tailor-made star polymers can be employed as efficient conductors for lithium-ion, sodium-ion, and potassium-ion batteries. The lithium-ion conductivity of the solid-state polymer electrolytes obtained from a potassium cation template and poly(ethylene glycol) dimethacrylate (PEGDMA750) monomer (K-SPE750-Li) is 2.82 × 10 -5 S cm -1 at 20 °C. Furthermore, the cell of Li|K-SPE750-Li|LiFePO 4 shows stable cycling performance and a good rate property.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2021
·
IF 4.598
Qingfu Ban,Yan Li,Yusheng Qin,Yaochen Zheng,Jie Kong
Hyperbranched star copolymers are important soft materials that have been employed for aqueous self-assembly and bioapplication, but their one-pot one-batch synthesis strategy and relevant topology are rarely discussed. In this contribution, we produce hyperbranched star poly(vinyl ether ester)s (mPEG- hb -PVEEs) amphiphiles with multimodal molecular weight distribution via one-pot one-batch Am+Bn+C1 (m ≥ 2, n ≥ 3) step-growth polymerization. Based on the topological analysis of these hyperbranched star copolymers, a convenient expression of the number ratio of monomeric structural units (N A /N B ) is deduced to describe the cyclic defect of intramolecular cyclization only by using proton nuclear magnetic resonance spectroscopy. The introduction of long-chain terminators and the change in the molar feed ratio of A 2 :B 3 :C 1 considerably affect the N A /N B so as to give rise to increased influence of number of macromolecules and decreased influence of intramolecular cyclization, which are then responsible for an aqueous self-assembly behavior of mPEG- hb -PVEEs amphiphiles. Overall, this study opens new possibilities for the precise description of intramolecular cyclization and controllable synthesis of hyperbranched star copolymers via one-pot Am+Bn+C1 step-growth polymerization.
研究领域:
高分子科学
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材料科学
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化学工程
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生物技术
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DOI
高影响因子
ELECTROCHIMICA ACTA
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2019
·
IF 5.383
Ning Zhou,Yufeng Wang,Yang Zhou,Jinyou Shen,Yong Zhou,Yong Yang
Star-shaped polymeric ionic liquids (PIL-3 and PIL-4) based on poly(2-(dimethyl-ethyl-amino)ethyl methacrylate) bis(trifluoromethylsulfonyl)imide (P(EtDMAEMA-TFSI)) with three-arm and four-arm architectures were prepared through atom transfer radical polymerization (ATRP) and ion exchange. Subsequently, gel polymer electrolytes (GPEs) comprising PIL host, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)imide (DEME-TFSI) ionic liquid (IL) plasticizer with the same anion unit and LiTFSI salt were obtained. Compared with the linear PIL possessing the same elements, the increase of branches for PIL decreases the crystallity and glass transition temperature (T g ) of the corresponding GPEs. Accordingly, the ionic conductivity , electrochemical window and ion transport number of three-arm and four-arm PILs based GPEs (PIL-GPE-3 and PIL-GPE-4) are obviously superior to the linear contrastive sample. Among lithium metal batteries assembled by linear, three-arm and four-arm PILs based GPEs, Li/PIL-GPE-4/LiFePO 4 presents the best performance. The specific discharge capacity attains 151 mAh g −1 at 0.1 C, the capacity retention ratio achieves 93.6% after 100 cycles at 60 °C, and the coulombic efficiency is around 99%. The outstanding compatibility between PIL-4 and IL and the resulted interfacial stability between PIL-GPE-4 and electrodes both contribute to the excellent performance.
研究领域:
材料科学
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电化学
·
能源存储
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DOI
高影响因子
MACROMOLECULES
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2026
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IF 5.7
Kangle Zhou,Junhong Guo,Junchen Wu,Kun He,Suli Chen,Tianxi Liu
Poly(ethylene oxide) (PEO)-based solid electrolytes are pivotal for enabling high-safety and high-energy-density all-solid-state lithium metal batteries (ASSLMBs) yet remain fundamentally constrained by the inherent trade-off between ionic conductivity and mechanical robustness. Herein, we report a supramolecularly expanded polymer electrolyte engineered via a star boron-cored poly(ethylene glycol) (BPEG) macromolecule. The BPEG architecture incorporates a Lewis acidic boron core that promotes salt dissociation through anion-trapping, along with three flexible PEG arms that are intrinsically ion-conductive and structurally homologous to the PEO matrix. Critically, these PEG arms mediate the formation of a dynamic multiscale hydrogen-bond network between the PEO chains. This unique architecture, which disrupts PEO crystallization to unlock segmental motion, operates on a sequential relaxation mechanism: labile weak hydrogen bonds dissociate preferentially to facilitate Li+ transport, while robust strong hydrogen bonds persist to maintain mechanical integrity. Such design yields a robust yet adaptive supramolecular network that concurrently establishes continuous ion-conduction pathways and enhances structural robustness. As a result, the SEPE demonstrates high ionic conductivity, improved mechanical strength, and stable interfacial compatibility with lithium metal, enabling highly stable Li plating/stripping and delivering excellent performances in high-loading practical ASSLMBs. This work introduces a feasible multiscale relaxation supramolecular strategy for high-performance polymer electrolytes.
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DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2024
·
IF 3.9
Dandan Li,Wenrong Zhao,Gang Li,Yan Xu,Liang Xu,Bo Tang
Graphical Two novel star-shaped fluorophores named PDI−S and PDI−Se are constructed by S/Se-fused perylene diimides (PDIs) connected with bicarbazole core. Particularly, PDI−S presents excellent two-photon absorption cross-action (δ TPA ) of 3775 GM excited with 800 nm light, which is the highest value based on PDIs motif in the NIR−I region (700–900 nm). Two-photon absorption (TPA) has attracted growing attention over recent years owing to the wide range of applications in organic nonlinear optical (NLO) materials. The quantitative sensitivity of a two-photon molecular entity is determined by its TPA cross-section (δ TPA ). Perylene diimides (PDIs) are excellent n-type organic semiconductor materials demonstrating distinguished thermal, optical, and chemical stability. Nonetheless, PDIs-based scaffolds exhibit poor δ TPA in the NIR−I region (700–900 nm) due to the lack of suitable molecular design. Here, two novel star-shaped PDIs fluorophores, namely PDI−S and PDI−Se, were constructed by four periphery S/Se-fused PDIs connected with bicarbazole core. PDI−S manifested excellent δ TPA of 3775 GM, which are among the highest values reported for PDIs excited in the NIR−I region.
研究领域:
有机化学
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材料科学
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DOI
PubMed
高影响因子
Asian Journal of Pharmaceutical Sciences
·
2021
·
IF 6.598
Yong Xu,Shi Wang,Longshun Yang,Yuhang Dong,Yafang Zhang,Guoqing Yan,Rupei Tang
TPGS approved by FDA can be used as a P-gp inhibitor to effectively reverse multi-drug resistance (MDR) and as an anticancer agent for synergistic antitumor effects. However, the comparatively high critical micelle concentration (CMC), low drug loading (DL) and poor tumor target limit its further clinical application. To overcome these drawbacks, the pH-sensitive star-shaped TPGS copolymers were successfully constructed via using pentaerythritol as the initial materials, ortho esters as the pH-triggered linkages and TPGS active-ester as the terminated MDR material. The amphiphilic star-shaped TPGS copolymers could self-assemble into free and doxorubicin (DOX)-loaded micelles at neutral aqueous solutions. The micelles exhibited the lower CMC (8.2 × 10 −5 mg/ml), higher DL (10.8%) and long-term storage and circulation stability, and showed enhanced cellular uptake, apoptosis, cytotoxicity, and growth inhibition for in vitro MCF-7/ADR and/or MCF-7/ADR multicellular spheroids and in vivo MCF-7/ADR tumors via efficiently targeted drug release at tumoral intracellular pH (5.0), MDR reversal of TPGS, and synergistic effect of DOX and TPGS. Therefore, the pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages are potentially useful to clinically transform for enhanced MDR cancer treatment.
研究领域:
药学
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纳米技术
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癌症研究
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药物递送系统
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DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE
·
2019
·Vol. 30
·期 8
·1-14
·
IF 2.467
Wang Jun,Li Shunying,Chen Tingting,Xian Wenjiao,Zhang Huiwu,Wu Lei,Zhu Wenting,Zeng Qingbing
To enhance the bioavailability of protein therapeutants and improve the stability of storage and delivery, a series of branched amphiphilic block copolymers consisting of cholic acid (CA) initiated poly(D,L-lactide-co-glycolide) (CA-PLGA) and water-soluble polyethyleneimine cross-linked polyethylene glycol (PEI-PEG) denoted as CA-PLGA-b-(PEI-PEG) were synthesized and characterized. CA-PLGA-b-(PEI-PEG) presented low cytotoxicity by MTT and cck-8 assay. The cationic CA-PLGA-b-(PEI-PEG) micelles (diameter about 100 nm and zeta potential 34–61 mV) were prepared through self-assembly method, and complexed with insulin via electrostatic interaction to obtain nanoscale micelle/insulin complexes. The micelle/insulin complexes-loaded CA-PLGA microspheres (MIC-MS, 10.4 ± 3.85 μm) were manufactured by employing a double emulsion (W 1 /O/W 2 ) method. The in vitro insulin release behavior and in vivo hypoglycaemic effect of MIC-MS on streptozotocin (STZ) induced diabetic rats were compared with those of the insulin-loaded CA-PLGA microspheres (INS-MS, 7.8 ± 2.57 μm). The initial burst in vitro release of MIC-MS was markedly lower than that of INS-MS ( P < 0.01), and the pharmacological availability of MIC-MS via subcutaneous administration was 148.9% relative to INS-MS. Therefore, the cationic CA-PLGA-b-(PEI-PEG) micelles can effectively increase the bioavailability of insulin in CA-PLGA microspheres and can be considered as a potential protein carrier.
研究领域:
药学
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生物医学工程
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药物递送系统
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
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2014
·
IF 0.74
Yan Xue,Dafu Wei,Anna Zheng,Yong Guan,Huining Xiao
Cationic star polymers as drug/gene carriers have attracted increasing attention. Herein, environmental sensitivities and star-shaped architecture were combined into a well-defined gene carrier system, and further amphiphilic modification was conducted. The thermo- and pH-sensitive behaviors of poly[N,N-(dimethyl amino)ethyl methacrylate] (PDMAEMA) star polymers before and after amphiphilic modification in aqueous solutions were investigated. The observed lower critical solution temperature (LCST) increased with increasing arm length due to the increase of hydrophilicity. A significant decrease of the LCSTs with increasing pH and ionic-strength of the solution was found. The incorporation of MMA and BA lipophilic moieties decreased the LCST of the cationic star polymer due to enhanced hydrophobic interaction. As a potential gene carrier, the performance of star polymers on binding DNA was primarily evaluated via particle size, zeta potential, and gel retardation measurements. All the complexes formed stable small particles with diameter of 100∼150 nm at N/P ratio higher than 3.0. The electrostatic screening effect and facilitation for the interaction of complexes with cell membrane induced by the incorporation of lipophilic units were expected to enhance the gene transfection efficiency.
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DOI
高影响因子
危险品化学品经营许可证（带存储）