CARBOHYDRATE POLYMERS
·
2014
·
IF 3.916
Jiachang Huang,Li Zhou
The hydrolyzed peach gum polysaccharide (HPGP) prepared at acidic condition is investigated as an anionic polyelectrolyte for the first time. A hydrolysis mechanism is proposed by monitoring the hydrolysis efficiency and morphological change of crude peach gum, and the intrinsic viscosity of resulted HPGP as a function of hydrolysis time. Fourier transform infrared (FTIR) spectroscopy and ζ-potential measurements reveal that HPGP with multiple carboxylic groups is negatively charged in water in the pH range 3–11. The HPGP exhibits remarkable pH and ionic strength responsiveness, as proven by dynamic light scattering (DLS) and atomic force microscopy (AFM) measurements. Moreover, the layer-by-layer (LbL) self-assembly experiments further confirmed that the HPGP can be utilized as an anionic polyelectrolyte . Considering the facile availability, favorable compatibility and intriguing functionality of HPGP, this study opens up enormous opportunities for the large-scale utilization of peach gum resource.
研究领域:
高分子科学
·
生物材料
·
纳米技术
·
药物递送
·
表面化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 89
·72444-72452
·
IF 3.84
Hui Liu,Si Chen,Huanqing Cui,Jin Hu,Hongyan Cai,Wenkai Deng
The uniformly dispersed and structured silica nanoparticles were prepared and functionalized by amino and 2-bromoisobutyrate successively. The random copolymer brushes of 2-(dimethylamino) ethyl methacrylate (DMAEMA) and 1′-(2-acryloxyethyl)-3′,3′-dimethyl-6-nitrospiro-(2H-1-benzopyran-2,2′-indoline) (SPMA) were synthesized from 2-bromoisobutyrate-functionalized silica nanoparticles by surface-initiated atom transfer radical polymerization (SI-ATRP). FT-IR, TGA, XPS, TEM, and EDS verified the successful immobilization of initiator and grafting of the random copolymer. Subsequently, the triple responsive behaviors including thermo-, pH- and photo-sensitivities were investigated using dynamic light scattering (DLS) as well as UV-Vis spectrometry. Furthermore, the active palladium was loaded into the hybrid silica nanoparticles and the catalytic performance was evaluated using a styrene hydrogenation reaction at different temperatures.
研究领域:
高分子化学
·
纳米材料科学
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催化化学
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智能响应材料
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表面功能化
·
有机合成
✓ 已验证
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Yanzhi Zhao,Juying Zhou,Fuhou Lei,Haitang Xu,Jianfang Lu,Zaiying Huang,Qin Huang,Pengfei Li
In this work, amphiphilic acrylicpimaric acid polyglycol ester (APAPG) was synthesized by steglich esterification method. The structure transformation and aggregation behaviors of APAPG in water were investigated by Rayleigh light scattering (RLS) technique in a heating and cooling cycle. For concentration above critical micelle concentration (CMC), a reversible transition from micelle to aggregation was observed. The structure transformation process involved irreversible aggregation and disaggregation processes at low temperature and a reversible aggregation process at high temperature when the concentration closed to CMC. Accordingly, the information about each structure transformation behavior in the concentration far below CMC during heating process including individual unimers, aggregation and disaggregation were thoroughly revealed. However, the structure transformation behavior is irreversible in the cooling process. The structure transformation and aggregation behaviors were assessed by dynamic light scattering (DLS), microcalorimetry and scanning electron microscopy (SEM) techniques. The results indicate that the RLS technique can provide detailed information about structural evolution at molecular level of polymer chains.
研究领域:
高分子化学
·
胶体与界面化学
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药物递送系统
·
生物材料
·
纳米医学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 38
·21613-21620
·
IF 2.936
Xiaoteng Zhou,Lingxiao Li,He Qin,Bo Ning,Junpei Li,Chengyou Kan
A series of amphiphilic PDMAEMA–SS–PCL chains with variable ratios of hydrophilic poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) to hydrophobic poly(ε-caprolactone) (PCL) were prepared via ring-opening polymerization, in which the two different moieties were linked via a disulfide bond with reduction responsiveness. After cross-linking by the photodegradable o-nitrobenzyl linkage, the amphiphilic chains could self-assemble into microspheres, branched cylindrical micelles and vesicles, which were responsive to the reduction agent DL-dithiothreitol and UV light irradiation through different mechanisms.
研究领域:
高分子化学
·
纳米医学
·
药物递送
·
生物材料
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智能材料
·
自组装
·
还原响应
·
光响应
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 82
·67247-67257
·
IF 3.84
Huilong Guo,Yinwen Li,Jian Zheng,Jianqun Gan,Liyan Liang,Kun Wu,Mangeng Lu
In this work, a novel epoxy monomer denoted as 3,5′-di-t-butyl-5,3′-dimethyl biphenyl diglycidyl ether (t-BuMBPDGE) was synthesized and applied into in situ composites with 3,3′,5,5′-tetramethyl-4,4′-biphenyl diglycidyl ether (TMBPDGE), accompanied with curing agent aromatic amines. The liquid crystalline phase structure and the crosslink density of substituted biphenyl epoxies were determined by polarized optical microscopy, wide angle X-ray diffraction measurements and dynamic storage moduli data. The samples showed good mechanical properties and could recover quickly from a second state to their initial states with a shape fixity ratio higher than 98% and shape recovery ratio higher than 99%, owing to the oriented structure and increased crosslink network density caused by the orientation of biphenyl mesogenic. The high glass transition temperatures ranging from 160 to 178 °C and good water resistance could contribute to a stable fixed shape. The water resistance is analyzed by contact angles test. The samples exhibited contact angles of 92–98 degrees, which indicated that the water resistance was apparently better than that of conventional epoxy systems.
研究领域:
高分子材料
·
功能材料
·
化学工程
·
材料科学
·
纳米复合材料
·
智能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 129
·期 2
·846-852
·
IF 1.289
Hong Yu Yang,Xiu Mei Zhang,Li Jie Duan,Ming Yao Zhang,Guang Hui Gao,Hui Xuan Zhang
A series of environmental pH-responsive block copolymers PEG-polyurethane with tertiary amine groups in the main chain and free carboxyl groups in the side chain were synthesized, including poly(ethylene glycol) (PEG), 1,4-bis (hydroxyethyl) piperazine, 1,6-diisocyanato hexamethylene, and 2,2-dimethylolpropionic acid. The chemical structure, molecular weight, and pH-dependent capacity of pH-responsive PEG-polyurethane were examined by 1 H-NMR, FTIR, gel permeation chromatography (GPC), and an acid-base titration. Moreover, the fluorescent dye fluorescein isothiocyanate was conjugated with PEG-polyurethane by the similar polymerization method and the obtained polymer was measured by ultraviolet visible spectroscopy (UV-vis) and fluorescent spectroscopy. The results indicated that the pH-responsive PEG-polyurethane showed a pH-buffering phenomenon and fluorescent imaging in a range of pH values. As a result, we demonstrated its potential application for optical imaging; however, it is believed that more applications in the areas of biomedicine will be possible owing to its free carboxyl acid terminal residues in the stimuli-responsive polymer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
研究领域:
生物材料
·
分子影像学
·
高分子化学
·
纳米医学
·
药物递送
·
生物传感器
·
转化医学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2012
·Vol. 213
·期 20
·2192-2200
·
IF 2.361
Xiao-Hui Dai,Chun-Yan Hong,Cai-Yuan Pan
A novel double-hydrophilic block copolymer P(MEO 2 MA- co -OEGMA)- b -PAMA has been successfully synthesized by two-step RAFT polymerization. Then, the amino groups of PAMA blocks in the copolymers react with 1-pyrenecarboxaldehyde via a “Schiff-base” reaction, and the resulting copolymers are self-assembled to form spherical micelles in aqueous solution. Because the “Schiff-base” linkage is pH sensitive, the release rate of pyrene depends upon the pH of solution. Complete release is achieved at pH 1, and the control release is much faster at pH 5.5 than that at pH 7.4. With progress of pyrene release, the micelles are disassembled gradually and disappeared completely at last. This double-hydrophilic copolymer is a promising candidate of drug carrier for the aldehyde- containing hydrophobic drugs.
研究领域:
高分子化学
·
药剂学
·
纳米医学
·
生物材料
·
药物递送系统
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2014
·
IF 2.354
Shangyang Li,Pengyao Xing,Lin Zhang,Feifei Xin,Jinhui Nie,Hailu Wang,Mingfang Ma,Yurong Wu,Aiyou Hao
Herein, we report a novel responsive assembly system consisting of an amphiphilic drug fenspiride and β-cyclodextrin in host–guest approach. Fenspiride molecules can self-assembled into vesicles in aqueous solution. The obtained vesicles were characterized in detail by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Furthermore, such a vesicular structure will be destroyed upon the addition of β-cyclodextrin due to the formation of inclusion complexes by host–guest interactions. In addition, amylase is a digestive enzyme which can catalyze the breakdown of starch into sugars. Adding α-amylase into the system could release fenspiride molecules, and trigger the self-assembly of fenspiride molecules again. It is anticipated that this research will provide widespread applications in the fields of responsive materials and biochemistry related to enzyme-responsive model system and host–guest chemistry.
研究领域:
药物化学
·
纳米医学
·
分子药剂学
·
生物材料
·
酶学
·
超分子化学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2016
·Vol. 217
·期 9
·1047-1056
·
IF 2.495
Liang Qiu,Chao-Ran Xu,Feng Zhong,Chun-Yan Hong,Cai-Yuan Pan
Pure cross-linked spherical micelles, nanowires, and vesicles are successfully fabricated from poly(2-hydroxypropyl methacrylate- b - p -(methacryloxyethoxy)benzaldehyde)s (PHPMA– b –PMAEBAs) through reversible addition-fragmentation chain transfer dispersion polymerization of MAEBA in methanol using PHPMA as a macro-CTA and subsequent cross-linking. The cross-linking reaction is conducted by stirring a mixture of 1,4-butanediamine and the resultant nano-objects in methanol at room temperature. For all polymerizations with feed molar ratios of MAEBA/PHPMA ranging from 75/1 to 240/1, the monomer MAEBA conversions are almost complete, and block copolymers with controlled molecular weight are obtained. The transmission electron microscopy, dynamic light scattering, and gel permeation chromatography results reveal that the following three factors significantly influence the morphology of the nano-objects: the feed molar ratio of MAEBA/PHPMA, the copolymer concentration, and the degree of polymerization of PHPMA. The cross-linked nano-objects are very stable in good solvents, the spheres and nanowires slightly decrease in size after cross-linking, whereas the vesicles slightly increase in size. The cross-linked nano-objects are stable in neutral solutions, but they dissociate in weekly acidic solutions. The loading of 1-pyrenemethylamine (PMA) into the vesicles and the unloading of PMA from the vesicles are studied.
研究领域:
高分子化学
·
纳米材料
·
药物递送
·
生物医学工程
·
胶体与界面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2021
·
IF 3.995
Jianhua Zhou,Hong Li,Yannan Li,Xiang Li
Cellulose nanocrystals (CNCs) were modified using an amphiphilic triblock copolymer [poly(2-(dimethylamino) ethyl methacrylate)- b -poly(glycidyl methacrylate)- b -poly(2,2,3,4,4,4-hexafluorobutyl acrylate) (PDMAEMA- b -PGMA- b -PHFBA)] bearing epoxy functionalities located in middle segment of PGMA, which were used to react with the hydroxyl groups on the surface of the CNCs. The triblock copolymer was synthesized via a reversible addition fragmentation chain transfer (RAFT) polymerization reaction between 2-(dimethylamino) ethyl methacrylate, glycidyl methacrylate and 2,2,3,4,4,4-hexafluorobutyl acrylate, and characterized using 1 H-NMR spectroscopy and size exclusion chromatography (SEC). The successful modification of the CNCs was demonstrated by means of FT-IR, TGA , TEM , XRD and XPS . In addition, the surface properties of the modified CNCs were studied using water contact angle and surface tension studies. When compared with the pristine CNCs, the modified CNCs exhibited a higher contact angle and lower surface tension. Good dispersion of the modified CNCs was observed in different polar solvents, such as water, THF, DMF , CHCl 3 and toluene. The modified CNCs exhibited pH responsive properties, which were measured using dynamic light scattering (DLS). In addition, the stability of Pickering emulsions stabilized by PDMAEMA- g -CNC- g -PHFBA decreased with time or increasing pH. The droplet size increased gradually upon increasing the pH. This work provides a method to design sophisticated CNC-based materials, which benefit from both the intrinsic properties of the CNCs and the new characteristics conferred by the multifunctional grafted chains.
研究领域:
高分子化学
·
纳米材料科学
·
胶体与界面化学
·
生物基功能材料
·
智能响应材料
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2016
·Vol. 4
·期 11
·1829-1837
·
IF 5.359
Yucheng Liu,Jiankun Sun,Zhou Yang,Dong Yang,Xiaodong Ren,Hua Xu,Zupei Yang,Shengzhong (Frank) Liu
CH 3 NH 3 PbX 3 (MAPbX 3 )-based perovskite has attracted tremendous research efforts in the last few years. With the discovery that the HC(NH 2 ) 2 PbI 3 (FAPbI 3 ) perovskite offers even higher solar cell efficiency, better thermal stability, and broader optical absorption, it is expected that it will provide more excitement in optoelectronic applications including laser, LED, photodetector, etc. The development in preparing large Single-Crystalline Formamidinium-Perovskite FAPbI 3 using the inverse-temperature reactive crystallization process, and associated wafer-slicing process is presented. The availability of the large Single-Crystalline Formamidinium-Perovskite Wafer makes it possible to fabricate integrated circuits. An array of 153 photodetectors on a piece of thin wafer, demonstrating feasibility of mass production of integrated circuits on the perovskite wafer is designed and prepared. It is found that the wafer-based photodetector shows much superior performance, with 90 times higher photoresponse and broader optical absorption than its thin-film perovskite counterpart.
研究领域:
材料科学
·
半导体物理
·
光电子学
·
晶体生长
·
器件 fabrication
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Zanru Guo,Hongjian Gu,Qiang Chen,Zhanfeng He,Wenyuan Xu,Jiali Zhang,Yongxin Liu,Leyan Xiong,Longzhen Zheng,Yujun Feng
Hypothesis The effective separation and recovery of oils from water is important for the protections of ecosystems and the environment. Polymeric porous monoliths have been demonstrated as attractive absorbents for oil/water separation. However, the recyclability was mainly realized by squeezing, combustion, or centrifugation, which may restrict in elastic materials, destroy the adsorbates or need special apparatus. Thus it is desirable to developing monoliths with controllable oil absorption and desorption. Experiments A series of “smart” monoliths with pH-induced switchable wettability were fabricated by high internal phase emulsion (HIPE) polymerization and epoxide ring-opening for the incorporation of amine groups. The resultant monoliths and their wettabilities were examined using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), nitrogen adsorption/desorption and contact angle analysis, respectively. The oil separation efficiency and recyclability were evaluated. Findings The monoliths with macroporous structure can undergo switchable wettability under reversible pH stimulation. As an absorbent, the monoliths not only separated and recovered organic solvents and oils (including crude oil) from aqueous mixtures through a reversible and recyclable absorption and desorption process upon alternating the pH between 7.0 and 1.0, but also continuously expulsed oils from water surfaces in a continuous manner with the aid of external driving pressures. Moreover, the monoliths also allowed the effective separation of surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency.
研究领域:
环境科学
·
高分子材料
·
分离科学
·
界面化学
·
功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）