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Chinese Journal of Polymer Science 2024年第1期42卷 1-6,I0004页

作者： Zi-Shan Li Jing Lyu Bei Qiu Ying-Hao Li Ruth Foley Ri-Jian Song Melissa Johnson Qiang Geng Wen-Xin Wang Institute of Precision Medicine(AUST-IPM) Anhui University of Science and TechnologyHuainan 232001China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin D04 V1W8Ireland

Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RDRP) of the water-soluble monomer nisopropylacrylamide(nIPAM) has been challenging with the problems of high dispersity, poor control over the molecular weights(MWs) or complex or multi reaction steps, etc. In this work, we report the well-controlled polymerization of nIPAM in water via a facile one-pot and one-step Cu(0)-mediated RDRP. The results of this approach show that the key for kicking off the Cu(0)-mediated nIPAM RDRPs is to ensure sufficient Cu~I at the very beginning, and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process. For nIPAM, which has a high propagation rate constant, the deactivation control can be effectively enhanced by extra adding deactivator(i.e., Cu~II) to the system. Moreover, a low reaction temperature(4 ℃) is necessary in the controlled synthesis of higher MW poly(nisopropylacrylamide)(PnIPAM) to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST). Through this new kinetically controlled strategy, PnIPAMs with well-defined structure, narrow molecular weight distributions(MWDs) and varied MWs were successfully achieved.

关键词： Cu(0)-mediated RDRP n-isopropylacrylamide Propagation Deactivation Reaction parameters

The Preparation and Properties of Thermosensitive Hydrogels Based on Chitosan Grafted n-isopropylacrylamide via γ-Radiation

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Chinese Chemical Letters 2004年第10期15卷 1253-1254页

作者： Hong CAI Jing ZHAnG Zheng Pu ZHAnG Yan Geng ZHAnG Bing Lin HE State Key Laboratory of Adsorption and Separation Functional Polymeric Materials Institute of Polymer ChemistryNankai UniversityTianjin300071 The Tianjin Institute of Technological Physics Tianjin 300192

Thermosensitive hydrogels were prepared by graft polymerization of chitosan and n-isopropylacrylamide via 60Co γ-radiation. The effects of monomer concentration and total irradiation dose on percent grafting and graf... 详细信息

关键词： γ-radiation Chitosan Graft n-isopropylacrylamide Thermosensitive

Preparation and Chiral Recognition of Thermosensitive Poly（n-isopropylacrylamide） Microgels Containing Modified L-Phenylalanine Groups

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Chemical Research in Chinese Universities 2015年第4期31卷 664-668页

作者： CHEn Jiaojiao YIn Yue FU Hongjun LI Qifeng ZOU Jiwei State Key Laboratory of Separation Membranes and Membrane Process School of Environmental and Chemical Engineering Tianjin Key Laboratory of Fiber Modification and Functional Fiber and Textile Division Tianjin Polytechnic University Tianjin 300387 P. R. China

Thermosensitive poly[n-isopropylacrylamide（nIPAM）-co-n-acryloyl-L-phenylalanine ethyl ester （nALPE）] microgels were prepared by the free radical polymerization of nIPAM and chiral monomer, nALPE. Such microgels exhibited spherical shape and favorable monodispersity. Increasing the content of nALPE units would en- hance the average diameter, but decrease the thermosensitivity and volume-phase transition temperatures of the mi- crogels. Compared with PnIPAM microgels, the microgels containing nALPE units performed chiral recognozable capacities for D-phenylalanine and D-tartaric acid, and the enantioselectivity and adsorption capacity of the microgels improved with increasing the temperature and/or the content of nALPE units.

关键词： Thermosensitive microgel n-isopropylacrylamide L-Phenylalanine Chiral recognition

Studies on LCST of poly (n-isopropylacrylamide-co-acrylic acid-co-n-diacetone acrylamide)

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Chinese Chemical Letters 2007年第1期18卷 79-80页

作者： Cai Hua ni Xiao Xia Zhu Qing Lan Wang Xian Yu Zeng School of Chemical and Material Engineering Southern Yangtze University Wuxi 214036 China Key Laboratory of Functional Polymer Materials School of Chemistry Polymer Institute Nankai University Tianjin 300073 China College of Material Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

Linear copolymers from n-isopropylacrylamide （nIPA）, acrylic acid （AA） and diacetone acrylamide （DAA） have been prepared. The effect of composition, ionic strength and pH on their lower critical solution tempera... 详细信息

关键词： LCST Thermo-responsive n-isopropylacrylamide n-Diacetone acrylamide

Graft copolymerization of n-isopropylacrylamide with 3-(methacryloxy)propyl trimethoxysilane on ultrafine silica and its application in chromatography separation

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Frontiers of Chemical Science and Engineering 2008年第3期2卷 242-247页

作者： Liping ZHAnG Yi ZHU Caihua nI School of Chemical and Material Engineering Jiangnan UniversityWuxi 214122China

Thermosensitive core-shell particles were synthesized through graft copolymerization of n-isopropylacrylamide with[3-(methacryloxy)propyl]trimethoxysilane(MPT)coupled on the surface of ultrafine silica *** copolymerization was carried out using polyvinyl alcohol as a surfactant,water and cyclohexanol as mixed solvent,and 2,29-azobis(isobutyronitrile)as an *** effect of surfactant concentration and the composition of the mixed solvent on the graft rate were *** structure of modified silica was confirmed by infrared *** scanning calorimetry(DSC)has revealed the thermosensitivity of the *** thermosensitive particles were used as packing materials of high performance liquid chromatography(HPLC)columns for separating naphthalene *** separation was obtained by controlling the temperature of the *** contrast,the packing material of silica-MPT has no such separation efficiency due to the lack of *** effect of the composition of the mobile phase on the separating efficiency was also *** temperature-controlled separation was effective only when the water content was higher than 90%(v/v)in the water-methanol mobile *** mechanism for the temperature-controlled separation is attributed to a polarity change of poly(n-isopropylacrylamide)which undergoes volume phase transition on the silica surface as the temperature increases.

关键词： n-isopropylacrylamide thermosensitivity separation HPLC graft copolymerization

Polymeric nanohydrogels of Poly(n-isopropylacrylamide)Combined with Others Functionalized Monomers:Synthesis and Characterization

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Journal of Biomaterials and nanobiotechnology 2014年第1期5卷 31-38页

作者： Lissette Aguero Luztono Yuneivy Cepero Donates Luis Guillermo Guerrero Ramirez Addys Gonzalez Palomo Dionisio Zaldivar Silva Issa Katime Departamento de Quimica Macromolecular Centro de BiomaterialesUniversidad de La HabanaHabanaCuba Grupo de nuevos Materiales y Espectroscopia Supramolecular Facultad de Ciencias y TecnologiaBilbaoEspana Departamento de Biologia de Sistemas Centro de Inmunologia MolecularHabanaCuba

nanohydrogels from inverse microemulsion (w/o) polymerization, at 25°C, of n-isopropylacrylamide (nIPA) and functionalized monomers are described. The functionalized monomers were: n-(pyridine-4-ylmethyl) acrylamide (nP4MAM) and tert-butyl 2-acrylamidoethyl carbamate (2AAECM). The polymeric nanohydrogel obtained was characterized by attenuated total reflectance Fourier-transformed infrared spectroscopy (ATR-FTIR) and proton nuclear magnetic resonance spectrometry (1HnMR), while their morphology and particle size was assessed by scanning electron microscopy (SEM) and dynamic light scattering. Their thermal properties were studied by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). As a preliminary measure of biocompatibility, in vitro evaluations of the nanohydrogels were carried out by cellular toxicity (colon carcinoma cells, CT-26) and hemocompatibility tests. These evaluations showed that these nanohydrogels were not toxic in the examined concentration range and exhibited preliminary blood compatibility;therefore they could be used in biomedical applications.

关键词： n-isopropylacrylamide nanohydrogels Inverse Microemulsion Polymerization In Vitro Biocompatibility

Dual thermo- and ion-responsive cross-linked poly（n-isopropylacrylamide） hydrogels incorporated with crown ether receptors

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Dual thermo- and ion-responsive cross-linked poly（N-isoprop...

Preparation of Thermal-responsive Chitosan-graft-n-isopropyl- acrylamide Membranes via γ-Ray Irradiation

The 4th Joint China/Japan Chemical Engineering Symposium

作者： Xiao-Jie Jua Liang-Yin Chua b Li Liua Peng Mia Ming-Yu Zhouaand Shi-Bo Zhanga a School of Chemical Engineering Sichuan University Chengdu Sichuan 610065 China.b Institute for nanobiomedical Technology and Membrane Biology State Key Laboratory of Biotherapy Sichuan University Chengdu Sichuan 610065 China.

Dual thermo- and ion-responsive cross-linked poly（n-isopropylacrylamide-co-benzo-18-crown-6-acrylamide）（P（nIPAM-co-BCAm）） hydrogel was successfully prepared via thermally-initiatedfree-radical cross-linking copolymerization. Both the structures and stimuli-sensitive properties of theprepared hydrogel were characterized. The results indicated that the incorporation of crown ether groups intothe poly（n-isopropylacrylamide） chains produced a smart hydrogel that responded to both temperature andion stimuli. When the crown ether units captured Ba2+ ions in their cavities and formed stable BCAm/Ba2+complexes, the lower critical solution temperature （LCST） of the hydrogel increased due to the repulsionamong charged BCAm/Ba2+ complex groups and osmotic pressure within the hydrogel resulted from aDonnan potential that arose from mobile counter ions to the crown ether bound Ba2+. Whereas crown etherscaptured Cs+ ions, the LCST shifted to a lower temperature because of the formation of 2:1 sandwichcomplexes. Unexpectedly, the LCST of the cross-linked P（nIPAM-co-BCAm） hydrogel in K+ solution didnot shift to a higher temperature, which was definitely different from the previously reported linearP（nIPAM-co-BCAm） copolymer in K+ solution. The reason may be due to the following: if the copolymerchains were cross-linked, the cavities of crown ethers were close to each other;because the stability constantof BCAm/K+ complex is not high enough, therefore the electrostatic repulsion among K+ ions affected theformation of stable BCAm/K+ complexes inside the cross-linked P（nIPAM-co-BCAm） hydrogel. The resultsof this work provide valuable information for development of dual thermo- and ion-responsive hydrogelswhich have potential applications in drug controlled-release systems or biomedical fields.

关键词： hydrogel ion-responsive n-isopropylacrylamide benzo-18-crown-6-acrylamide

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Chinese Chemical Letters 2006年第9期17卷 1236-1238页

作者： Qing MU Yue E FAnG Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026

A novel thermo-sensitive switching membrane has been prepared by radiation-induced simultaneous grafting n-isopropylacrylamide （nIPAAm） onto chitosan membrane. Fourier transform infrared spectroscopy （FTIR） was used to identify the structure of the grafted membranes. The surface morphology of the grafted membrane was observed from scanning electron microscopy （SEM）. Pure water flux measurements showed that water flux of the grafted membrane decreased with the increase of temperature, while that of chitosan membrane was constant. It was proved that grafted membrane was sensitive to temperature.

关键词： Chitosan membrane n-isopropylacrylamide γ-ray irradiation thermal-responsive.

Fabrication of a superhydrophilic/underwater superoleophobic stainless steel mesh for oil/water separation with ultrahigh flux

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Frontiers of Chemical Science and Engineering 2023年第1期17卷 46-55页

作者： Jiawei Wang Jie Hu Junjie Cheng Zefei Huang Baoqian Ye School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China

Because of the increasing amount of oily wastewater produced each day,it is important to develop superhydrophilic/underwater superoleophobic oil/water separation membranes with ultrahigh flux and high separation *** this paper,a superhydrophilic/underwater superoleophobic n-isopropylacrylamide-coated stainless steel mesh was prepared through a simple and convenient graft polymerization *** obtained mesh was able to separate oil/water mixtures only by *** addition,the mesh showed high-efficiency separation ability(99.2%)and ultrahigh flux(235239 L·m^(−2)·h^(−1)).Importantly,due to the complex cross-linked bilayer structure,the prepared mesh exhibited good recycling performance and chemical stability in highly saline,alkaline and acidic environments.

关键词： oil/water separation n-isopropylacrylamide stainless steel mesh ultrahigh flux

Self-assembly of Hollow PnIPAM Microgels to Form Discontinuously Hollow Fibers

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Chinese Journal of Polymer Science 2014年第11期32卷 1544-1549页

作者： Xiao-yun Liu Jian-mao Yang 查刘生 Zi-jun Jiang Research Center for Analysis and Measurement Donghua University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University

A new kind of hollow hydrogel microfiber with discontinuous hollow structure was prepared by an ice-segregation-induced self-assembly process. Monodisperse thermo-responsive hollow poly（n-isopropylacrylamide）（PnIPAM） microgels were first synthesized by seed precipitation polymerization using colloidal Si O2 nanoparticles as seeds, followed by removing the silica cores of the formed Si O2/PnIPAM core/shell composite microgels with hydrofluoric acid. Then, the discontinuously hollow hydrogel microfibers were produced by unidirectional freezing of 1 wt% hollow PnIPAM microgel aqueous dispersion in liquid nitrogen bath, followed by freeze-drying to remove the formed ice crystals. Many orderly arrayed dents were observed on the surfaces of the hydrogel microfibers by field-emission scanning electron microscopy, indicating that they are constructed by closely packed monodisperse hollow PnIPAM microgels. The effect of freezing method and the hollow microgel concentration in the aqueous dispersion on the morphological structure of the hollow hydrogel microfibers was investigated.

关键词： Discontinuously hollow microfiber Ice-segregation-induced self-assembly Thermo-responsiveness n-isopropylacrylamide Microgel.