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Preparation and Properties of polyvinyl Chloride/Carbon Nanotubes Composite

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 516-520页

作者： TAO Jiashun QIN Yujun GUO Zhixin Department of Chemistry Renmin University of China

Chemically functionalized carbon nanotubes were combined with PVC to enhance both toughness and strength by simply mixing long alkyl chain modified multi-wall carbon nanotubes (abbreviated as MWNTs) or Ester-functionalized soluble MWNTs (abbreviated as eMWNTs) with PVC in Tetrahydrofuran (THF)/Cyclohexanone (CH) solution to obtain good dispersity solution. The MWNTs modified with 1-Bromohexadecane can effectively increase the intermolecular force with PVC by hydrogen bond. The obtained nanocomposite has a regular shape with homogeneously dispersed particles. PVC/2 wt% eMWNTs has been proved to possess excellent thermal stability. The intermolecular force between eMWNTs and PVC endows the as-fabricated nanocomposite with enhanced toughness and strength, indicating that our method is promising for wide use in PVC/eMWNTs nanocomposition.

关键词： polyvinyl chloride (PVC) toughness and strength MWNTs

Fabrication and Characterization of One Interpenetrating Network Hydrogel Based on Sodium Alginate and polyvinyl Alcohol

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 744-751页

作者： ZHANG Shangwen HU Yan School of Pharmaceutical Science South-Central University for Nationalities

One interpenetrating network hydrogel based on sodium alginate (SA) and polyvinyl alcohol (PVA) was synthesized by combining the raw materials of PVA and SA with the double physical crosslinking methods of freezing thawing and Ca2+ crosslinking. The PVA-SA composite hydrogel have been characterized by scanning electron microscopy for surface morphology, infrared spectroscopy for investigating the chemical interactions between PVA and SA, X-ray diffraction for studying the PVA-SA composite structure property and thermal gravimetric for understanding the PVA-SA composite thermal stability. The swelling behavior and the degradation rate of the PVA-SA composite hydrogel were studied in simulated gastrointestinal fluid. Using bovine serum albumin (BSA) and salicylic acid as the model drugs, the release behavior of the PVASA composite hydrogel on macromolecular protein drugs and small molecule drug were evaluated. The results showed that the water absorption and degradation ability of the PVA-SA composite hydrogel was much better compared to the pure SA hydrogel or pure PVA hydrogel. The hydrogel exhibited remarkable pH sensitivity and the network was stable in the simulated intestinal fluid for more than 24 h. With the advantages such as mild preparation conditions, simple method, less reagent and none severe reaction, the PVA-SA composite hydrogel is expected to be a new prosperous facile sustained drug delivery carrier.

关键词： composite hydrogel polyvinyl alcohol sodium alginate drug release behavior

Starch-g-poly (vinyl alcohol) as Compatibilizer for Reducing the Phase Separation Rates of polyvinyl Alcohol/Cornstarch Pastes

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Journal of Donghua University(English Edition) 2001年第3期18卷 38-41页

作者： Zhu Zhifeng(祝志峰) ZhouYongyuan(周永元) Department of Chemistry Wuhan University Wuhan 430072 College of Textiles Dong Hua University Shanghai 200051

Starch- g-poly(vinyl alcohol) as a compatibilizing agent for reducing the phase separation rates of polyvinyl alcohol/starch pastes has been investigated by blending and dissolving the two polymers in distilled water. The separation rates were quantitatively evaluated by the term of initiul demixing time. The grafted starches, with a series of grafting ratios, were prepared by grafting a number of vinyl acetate onto granular cornstarch in aqueous dispersion and then alcoholating in methanol. It was found that the addition of small amounts of starch- g poly (vinyl alcohol ) in the size compositions can effectively decrease the separation rates of the blended pastes in comparison to pure starch/PVA ***, the influence of the grafting ratio, starch content, and PVA variety on the separation rates was also studied.

关键词： warp size, compatibilizer , phase separation,starch, polyvinyl alcohol.

Study On the Method for Evaluating the Compatibility of polyvinyl Alcohol-starch Pastes

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Journal of China Textile University(English Edition) 2000年第4期17卷 66-70页

作者：祝志峰 Dep. of Chem. Wuhan Univ. Wuhan 430072 China

A revising method for evaluating the separation behavior of polyvinyl alcohol - starch pastes used as warp sizes had been studied and developed. Cosolvent method involves two important indexes for appraising the separation behavior: (l) initial demising time, and (2) subsidence ratio. However, they sometimes gave confused results because of the different measuring conditions. For obtaining the indexes accurately, the measuring parameters such as paste concentration, component content, and subsidence period of time were carefully studied and proposed. Besides accuracy, the proposed condition could give larger measuring scope and higher sensitiveness than the old one. Moreover, the influences of the paste concentration, component content, and molecular structure of polyvinyl alcohol upon the separation were also investigated. The experiments indicated that the paste concentration and starch content had much effect on the phase separation, whereas the influence of the molecular structure of polyvinyl

关键词： warp sizes phase separation determination starch polyvinyl alcohol

EFFECT OF MAGNETIC FIELD ON RADICAL POLYMERIZATION OF VINYL MONOMERS UNDER UV-IRRADIATION——STEREOREGULARITY OF POLYMER FORMED BY BULK POLYMERIZATION OF MMA INITIATED BY AIBN SENSITIZED WITH polyvinyl NAPHTHALENE (PVN)

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Chinese Science Bulletin 1989年第18期34卷 1539-1544页

作者：黄骏廉 Institute of Material Science. Fudan University Shanghai

It has been noticed that the properties of polymer, such as solubility, crystallinity and flexibility, strongly depend on the stereoregularity of polymer chains. For example, some big differences in glass transition temperature, crystallinity and mechanical behaviors could be found in isotactic, syndiotactic and atactic PMMA, isotactic and atactic pp, isotactic,

关键词： magnetic field ultra violet light polyvinyl naphthalene methyl methacrylate bulk polymerization

Preparation and Properties of Chitosan/polyvinyl Alcohol Blended Fiber Membrane for Medical Dressing

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Journal of Donghua University(English Edition) 2019年第5期36卷 466-470页

作者： SUN Wei HUANG Liangliang ZHANG Peihua Engineering Research Center of Technical Textiles Ministry of EducationShanghai 201620China College of Textiles Donghua UniversityShanghai 201620China

The antibacterial dressing prepared by the electrospinning can play a role in protecting the wound,preventing infection and promoting wound healing,and have broad application ***(CS)/polyvinyl alcohol(PVA)blended fiber membrane was successfully prepared by *** fiber morphology,thermal properties and material composition of CS/PVA blended fiber membrane were studied,and the interaction between CS and PVA was analyzed,and the optimum blend ratio was also *** glutaraldehyde(GA)steam cross-linking of the blended fiber membrane was carried out in order to improve the water resistance of the fiber *** the same time,the effect of different cross-linking time on the water resistance of fiber membrane was *** apparent morphology of the fiber membrane was observed by a scanning electron microscope(SEM).The results showed that with the increase of spinning solution concentration,the morphology of the fiber became more and more regular,and the fiber diameter increased *** intermolecular interaction between CS and PVA was found by Fourier transform infrared(FTIR)spectroscopy and thermal properties,which improved the spinnability of CS *** cross-linking,the water resistance of the fiber membrane was greatly improved,among which the effect of 4 h cross-linking was the best,and the water resistance of the fiber membrane increased by 64.89%.

关键词： chitosan(CS) polyvinyl alcohol(PVA) cross-linking water resistance

Swelling behavior of polyvinyl alcohol and lactic acid hydrogel films

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Asian Journal of Pharmaceutical Sciences 2016年第1期11卷 102-103页

作者： Jirapornchai Suksaeree Chitradee Luprasong Chaowalit Monton Department of Pharmaceutical Chemistry Faculty of PharmacyRangsit UniversityMuangPathum Thani 12000Thailand Sino-Thai Traditional Medicine Research Center(Cooperation between Rangsit University Harbin Institute of TechnologyHeilongjiang University of Chinese Medicine)Faculty of PharmacyRangsit UniversityMuangPathum Thani 12000Thailand Sun Herb Thai Chinese Manufacturing Plant Faculty of PharmacyRangsit UniversityMuangPathum Thani 12000Thailand

Hydrogel films are the thin-film formation that can absorb the water or biological fluids shown as hydrated polymer *** films have a potential as carriers for bioactive macromolecules,wound dressing,and controlled drug *** alcohol(PVA)is a biodegradable and biocompatible synthetic polymer which has been widely used in pharmaceutical *** work aims to study the swelling behavior of hydrogel films prepared from PVA and lactic acid(LA)intended to use as drug delivery system.

关键词： Hydrogel films Lactic acid polyvinyl alcohol Swelling

Uterine artery embolization in residual arterio-venous fistula due to invasive mole using glue and polyvinyl alcohol particles: Case report

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Open Journal of Obstetrics and Gynecology 2013年第1期3卷 24-31页

作者： Kishor Taori Jawahar Rathod Amit Disawal Anand Hatgaonkar Suresh Dhakate Ramesh Parate Shyam Chhadi Vishal Bakare Prasad Wavare Rakhi Puria Department of Radio-Diagnosis Government Medical College and Hospital Nagpur India

Gestational trophoblastic diseases (GTD) are one of the rare complications of pregnancy, which include partial and complete moles with their more aggressive counterparts termed as Gestational trophoblastic neoplasias (GTN). Their association with uterine vascular malformations is well recognised and should be suspected in appropriate clinical settings. Selective uterine artery embolization is a safe and effective alternative method of treatment in a patient with severe per vaginal bleeding from residual uterine vascular malformations due to GTN which has relative lower morbidity and mortality than surgical procedures. Here, we report a case of residual uterine arterio-venous malformation due to invasive mole detected by ultrasonography (US) and contrast enhancedMRI & referred to Interventional Radiology for Transcathetor arterial embolization.

关键词： Gestational Trophoblastic Diseases and Neoplasias Glue polyvinyl Alcohol Particles Selective Uterine Artery Embolization Vascular Malformation

Study on Various Compositions of polyvinyl Alcohol and Starch Blends by Cross-Linking with Glyoxal

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Open Journal of Polymer Chemistry 2019年第4期9卷 76-85页

作者： Ravindra V. Gadhave Prakash A. Mahanwar Pradeep T. Gadekar Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch blends. The blends have been cross-linked with glyoxal to enhance its properties. The hydroxyl groups of PVA and starch react with glyoxal via formation of acetal bonds;hence crosslinking could take place. The cross-linking of glyoxal is observed in various analytical methods such as DSC and FTIR. The cross-linked blends showed better thermal and mechanical properties. Viscosity, tensile shear strength, pencil hardness and ultimate stress were evaluated to estimate the changes due to cross-linking. It was observed that the cross-linking is directly proportional to starch, since the starch hydroxyl groups are easily accessible for reacting. The cross-linked blend showed better cohesion between its chains, thereby increasing glass transition temperature. It was reflected in the subsequent increase in tensile strength properties.

关键词： Starch polyvinyl Alcohol Cross-Linking Glyoxal Mechanical Testing