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Preparation and Swelling Kinetic Analysis of Poly (HPMC-co-AA-co-AM) Super Absorbent Resin

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 790-799页

作者：马砺 WANG Xin LIU Xixi WEI Gaoming GUO Ying School of Safety Science and Engineering Xi’an University of Science and TechnologyXi'an 710054China Key Laboratory of Coal Fire Disaster Prevention Xi’an University of Science and TechnologyXi'an 710054China School of Energy Engineering Xi’an Uni-versity of Science and TechnologyXi'an 710054China Yanzhou Coal Mining Co. Ltd.Zoucheng 237500China

Super absorbent resin(SAR)is prepared by aqueous high temperature polymerization using hydroxypropyl methylcellulose(HPMC)as monomer backbone material,acrylic acid(AA)and acrylamide(AM)as the graft copolymer monomer,potassium persulfate(KPS)as the initiator to generate free radicals,and N,N`-methylenebisacrylamide(MBA)as cross-linking agent for cross-linking reaction.Simutaneously,the influence of individual factors on the water absorption is investigated,and these factors are mainly AA,AM,KPS,MBA,HPMC,and reaction temperature.The optimized conditions are obtained by the experiment repeating for several times.The water absorption multiplicity and salt absorption multiplicity under the conditions are 782.4 and 132.5 g/g,respectivity.Furthermore,the effects of different temperatures and salt concentrations on its water absorption,as well as the swelling kinetics of SAR are studied.It is indicated the water-absorbing swelling process is mainly caused by the difference in water osmotic pressure and Na+concentration inside and outside the cross-linked molecular structure of the resin,which is not only consistent with the quasi-secondary kinetic model,but also with the Fick diffusion model.

关键词： super absorbent resin swelling kinetics water absorption graft copolymerization hydroxypropyl methyl cellulose

graft copolymerization OF VINYL MONOMERS ONTO STARCH INITIATED BY TRANSITION METAL-THIOUREA REDOX SYSTEMS

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Chinese Journal of Polymer Science 1996年第2期14卷 163-171页

作者：高建平田汝川张黎明 Department of Chemistry Tianjin University Tianjin 300072

In this paper, the capabilities of grafting acrylonitrile (AN) onto starch initiated by Fe(III)-TU, V(V)-TU, Cr(VI)-TU, Mn(VII)-TU redox systems were compared in the presence of sulfuric acid of different concentrations. It was shown that the grafting capability of Mn(VII)-TU is the highest in these initiating systems. Using Mn (VII-TU as initiator, the effects of various acids (HClO4, H2SO4, HNO3, HCl) on the graft copolymerization of acrylonitrile onto starch were discussed, and the capabilities of graft copolymerization of methyl methacrylate (MMA), acrylamide (AM), acrylic acid (AA) onto starch were investigated. The experimental results show that the order of the influences of different acids is HClO4 > H2SO4 > HNO3 > HCl, and the order of grafting capabilities of different monomers grafted onto starch is MMA > AN > AM > AA. The structure and morphology of graft, copolymers were studied with infrared spectroscopy and scanning electron microscopy. The size, shape and roughness of surface of the grafted starch granules are changed after grafting.

关键词： transition metal thiourea graft copolymerization starch

graft copolymerization OF ACRYLAMIDE ONTO THE UV-RAY IRRADIATED FILM OF POLYESTER-POLYETHER

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Chinese Journal of Polymer Science 1988年第1期6卷 14-19页

作者：陈传福李学芬李执芬 Academia Sinica Beijing Institute of Chemistry

In this paper the Ce(Ⅳ) salt initiated graft copolymerization of acrylamide onto the film of polyesterpolyether block copolymer irradiated by UV-ray was reported. The UV-irradiation of the film and its graft process have been investigated by UV spectrum, ESR and ESCA and the influence of other factors on the graft copolymerization has been discussed.

关键词： Polyester-Polyether block copolymer graft copolymerization UV-irradiation 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 beads.The copolymerization was carried out using polyvinyl alcohol as a surfactant,water and cyclohexanol as mixed solvent,and 2,29-azobis(isobutyronitrile)as an initiator.The effect of surfactant concentration and the composition of the mixed solvent on the graft rate were investigated.The structure of modified silica was confirmed by infrared spectra.Differential scanning calorimetry(DSC)has revealed the thermosensitivity of the particles.The thermosensitive particles were used as packing materials of high performance liquid chromatography(HPLC)columns for separating naphthalene derivatives.Satisfactory separation was obtained by controlling the temperature of the column.In contrast,the packing material of silica-MPT has no such separation efficiency due to the lack of thermosensitivity.The effect of the composition of the mobile phase on the separating efficiency was also investigated.The temperature-controlled separation was effective only when the water content was higher than 90%(v/v)in the water-methanol mobile phase.The 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

graft copolymerization of cellulose and 2-hydroxyethyl methacrylate in an ionic liquid

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Forestry Studies in China 2011年第3期13卷 245-251页

作者： XIAO Shu XIN Ting-ting HE Jing College of Materials Science and Technology Beijing Forestry University Beijing 100083 E R. China

Dissolution and homogeneous graft copolymerization of cellulose were performed in an ionic liquid 1-allyl-3-methylimidazolium chloride （AmimCl） with 2-hydroxyethyl methacrylate. The synthesized AmimCl and cellulose graft copolymers were characterized by FTIR, ^1 H-NMR and XRD spectroscopy. The results show that AmimCl dissolved cellulose directly by destroying intermolecular and intramolecular hydrogen bonds in cellulose and the crystalline form of cellulose was transformed from cellulose Ⅰ to cellulose Ⅱ after regeneration from AmimCl. The best synthetic condition of the cellulose-graft-P （2-hydroxyethyl methacrylate） was that cellulose 0.5 g, 2-hydroxyethyl methacrylate 3.00 g and initiator ammonium persulfate 0.05 g reacted for 180 min at 60℃; the rate of grafting reached 77.3%.

关键词： cellulose ionic liquid dissolution graft copolymerization

THE EFFECTS OF MAGNETIC FIELD ON graft copolymerization OF METHYL METHACRYLATE ONTO POLYVINYL ALCOHOL IN THE PRESENCE OF BENZOPHENONE DURING UV IRRADIATION

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Chinese Journal of Polymer Science 1990年第2期8卷 108-114页

作者：黄骏廉邬青峰 Institute of Material Science Fudan University Shanghai

The effects of magnetic field on the graft ratio and stereoregularity of grafts of PVA-g-MMA in the presence ofbenzophenone during UV irradiation are discussed. By means of IR, it was found that the graft ratio was increased with the increment of magnetic field strength. Furthermore, application of relative weak magnetic field of 0.4 Tesla had been shown to substantially enhance the stereo-regularity of graft copolymer. The maximum stereo-regularity appeared when the graft ratio approached to 85% with the magnetic field of 1.2 Tesla (T). The resistance to moisture and heat resistance of the grafted copolymer in the presence of magnetic field were also improved.

关键词： Magnetic field graft copolymerization Methyl methacrylate Polyvinyl alcohol Benzophenone UV irradiation

MODIFICATION OF SILK FIBER via EMULSION graft copolymerization WITH FLUOROACRYLATE

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Chinese Journal of Polymer Science 2008年第3期26卷 353-362页

作者：李战雄 College of Material Engineering Soochow UniversitySuzhou 215021China

2,2,3,3,4,4,5,5-Octafluoropentyl acrylate was grafted onto silk fiber in a two-step heterogeneous system through the vinyl bonds of acryloyloxyethyl isocyanate modified on the silk.The grafted copolylner was analyzed by FTIR and WAXD,and the results revealed that the fluoroacrylate was successfully grafted onto silk fiber and the crystalline structure of silk fibroin withβ-sheet structure was not changed after graft copolymerization.The FT-IR corrected method was used to simulate the grafting yield onto sil...

关键词： graft copolymerization Silk Fluoroacrylate Modification

In-line Plasma-induced graft-copolymerization of Pentaerythritol Triacrylate onto Polypropylene

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Chinese Journal of Polymer Science 2018年第8期36卷 979-983页

作者： Gui-Qiu Ma Guan-Kai Sun Zhe Ma Jing-Qing Li Jing Sheng Department of Polymer Material Science and Engineering Institute of Advanced Polymer MaterialsSchool of Material Science and EngineeringTianjin Key Laboratory of Composite and Functional MaterialsTianjin University

Pentaerythritol triacrylate （PETA） was successfully grafted onto the plasma-treated isotactic polypropylene （iPP） via the in situ melt processing. The X-ray photoelectron spectroscopy （XPS） results showed that the hydroxyl and carbonyl groups, and peroxides could be generated via plasma treatment. The content of free radical in plasma-treated iPP （PiPP） was measured by 2,2-diphenyl-1- picrylhydrazyl （DPPH）. It was found that the resulting peroxides induced the grafting copolymerization of PETA onto iPP, and the grafted PETA promoted the formation of β-crystal in PiPP, which was evidenced by Fourier transform infrared spectroscopy （FTIR）, differential scanning calorimetry （DSC） and wide-angle X-ray diffraction （WAXD） measurements, respectively.

关键词： Plasma treatment Melt processing graft copolymerization Pentaerythritol triacrylate

Modification of Natural Rubber Latex by graft copolymerization of 2-Ethylhexyl Acrylate and Methacrylic Acid

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Transactions of Tianjin University 2020年第4期26卷 314-323页

作者： Xueyuan Wang Fanglian Yao Jie Su Xin Zhang Xiaolei Tong Zhihui Qin Caideng Yuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China

Natural rubber(NR)grafted with 2-ethylhexyl acrylate(2-EHA)and methacrylic acid(MAA,collectively NR-g-PEHA/MAA)was synthesized by emulsion polymerization.Tetraethylenepentamine and cumene hydroperoxide were used as redox initiators.The successful grafting of 2-EHA and MAA onto NR was confirmed by Fourier transform infrared spectroscopy.The morphology of the NR latex particles was observed by transmission electron microscopy.The effects of reaction temperature,initiator dosage,feeding mode,and hard monomer content on the mechanical properties of the modified NR film were investigated.grafted polymer chains were unevenly wrapped on the outside of NR particles,and smaller particles were more easily grafted.Crosslinking was characterized using a toluene swelling method.Thermal stability and glass transition temperature were examined by differential scanning calorimetry and thermogravimetric analysis.The results showed that the thermal stability of NR-g-PEHA/MAA had been improved,and the glass transition temperature(Tg)was unchanged.

关键词： Natural rubber latex graft copolymerization Crosslinking Acrylate Aziridine