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  • Open Access

    ARTICLE

    Renewable Bis-benzoxazine Monomers from Lignin Derivatives: Synthesis, Characterization and Studies on Curing Behavior

    CHUNYAN LIU*, YUNHE LIU, ZIHAN PAN, QIUTING LI, HAN XU, TAO LIU

    Journal of Polymer Materials, Vol.36, No.1, pp. 87-99, 2019, DOI:10.32381/JPM.2019.36.01.7

    Abstract In this work, a series of novel lignin-based bis-benzoxazine monomers were efficiently synthesized by the reaction of renewable phenols: guaiacol, vanillyl alcohol, eugenol, vanillin with ethylene diamine and paraformaldehyde. The chemical structures of these lignin-based bis-benzoxazine monomers were confirmed by 1H-NMR, 13C-NMR and FTIR, indicating the formation of benzoxazine ring. The obtained bis-benzoxazine monomers were cured via thermal treatment. The curing behavior of these lignin-based bis-benzoxazine monomers were compared and analyzed via differential scanning calorimetry (DSC), showing that Va-e possessed higher ring-opening polymerization activity than G-e, while E-e and V-e had lower curing activity than G-e. More >

  • Open Access

    ARTICLE

    Synthesis and Characterization of New Chromophore 4-2-(2-hydroxy-5-(4 nitrophenyl) diazenyl) benzylidene) hydrazinyl) Benzoic Acid and its use in Chitosan Modification

    KAZIM SHAMIM RIZVI, P.K.DUTTA*

    Journal of Polymer Materials, Vol.36, No.1, pp. 75-85, 2019, DOI:10.32381/JPM.2019.36.01.6

    Abstract The present investigation deals with the preparation of carboxylic acid containing new chromophore : 4-2-(2-hydroxy-5-(4-nitrophenyl) diazenyl) benzylidene) hydrazinyl) benzoic acid and its use for chemical modification of chitosan, e.g., chitosan-acid salt complexes under mild conditions. Optical properties of chitosan acid complexes were evaluated by UV and SHG spectroscopy which showed red shift. Antibacterial activity of prepared chitosan acid complexes showed obvious effect against food pathogenic bacteria. The novel polymer complex was soluble in most of the organic solvents. More >

  • Open Access

    ARTICLE

    Development of Functional Adsorbent from Natural Biosorbent “Chitosan” by Radiation Induced Grafting of MAETC for the Removal of Arsenic (V)

    VIJAYASRI. K1, ALKA TIWARI1,*, C.V. CHAUDHARI2

    Journal of Polymer Materials, Vol.36, No.1, pp. 53-73, 2019, DOI:10.32381/JPM.2019.36.01.5

    Abstract High energy gamma radiation has been used to graft [2-(methacryloyloxyethyl) trimethylammonium chloride (MAETC) onto chitosan by radiation grafting method. Grafting yield was found to increase with the increase in radiation dose and monomer concentration. Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the grafted polymer and their morphological structure was analyzed by Scanning Electron Microscope (SEM). As(V) ions uptake capacity of the adsorbent was evaluated in different pH, contact time, temperature, adsorbent dose, and different arsenate ion concentration. The adsorption data was fitted well in the Langmuir model and various static parameters were calculated. More >

  • Open Access

    ARTICLE

    A Study on the Effect of Reaction Parameters on Viscosity and Molecular Weight of Hexafluoropropylene (HFP) based Perfluoropolyethers (PFPEs)

    SAURABH SAXENAa, PRATEEK MALIKa, GEETHA SESHADRIa,*, AJAY K. TYAGIa, UTTAM KUMAR MANDALb

    Journal of Polymer Materials, Vol.36, No.1, pp. 39-51, 2019, DOI:10.32381/JPM.2019.36.01.4

    Abstract Medium molecular weight liquid perfluoropolyethers (840 u to 1372 u) were synthesized by photopolymerization of hexafluoropropylene (HFP) in the presence of oxygen. Effects of various reaction parameters such as temperature, pressure, UV wattage and reaction time on yield, viscosity and molecular weight of PFPEs were studied. Out of all the parameters, the effect of reaction temperature was found the most significant on molecular weight of PFPEs. By increasing reaction temperature, viscosity and molecular weight of PFPEs where decreased. By increasing the wattage of the lamp, viscosity and molecular weight of PFPEs where also decreased. PFPEs More >

  • Open Access

    ARTICLE

    Synthesis and Physico-chemical Studies on Chalcone Based Epoxy Resin of (2E, 6E)-Bis (4-hydroxybenzylidene) cyclohexanone

    DHARMESH B. SANKHAVARA, JALPA CHOPDA, JIGNESH P. PATEL, P. H. PARSANIA*

    Journal of Polymer Materials, Vol.36, No.1, pp. 13-21, 2019, DOI:10.32381/JPM.2019.36.01.2

    Abstract Chalcone based epoxy resin (EBHBC) of (2E, 6E)- bis(4-hydroxybenzylidene) cyclohexanone (BHBC) was synthesized by condensing 0.5 mol BHBC and 2.5 mol epichlorohydrin in 500 mL isopropanol as a solvent and 1.0 mol NaOH in 50 mL water as a catalyst at 80o C. The structure of EBHBC is supported by spectral techniques. Molecular weights and molecular weight distribution of EBHBC were determined by gel permeation chromatography. DSC thermogram of EBHC showed one endothermic transition (146.1°C) and two endothermic transitions (253.52°C and 397.34°C) due to melting, some physical change and decomposition transitions, respectively. EBHBC is thermally More >

  • Open Access

    ARTICLE

    Improved Corrosion Resistance of Carbon Reinforced Aluminium Laminates in Atmospheric Environment: Role of Environment Friendly Jute Fibre/ Alumina nano Coating

    M. VASUMATHI1,a,*, VELA MURALI2,b, S. RASHIA BEGUM1,c, N. RAJENDRAN2,d

    Journal of Polymer Materials, Vol.36, No.1, pp. 1-11, 2019, DOI:10.32381/JPM.2019.36.01.1

    Abstract In the Fibre Metal Laminate (FML), Carbon Reinforced Aluminium laminate (CARALL), aluminium is placed next to carbon fibres. The potential difference between the aluminium and carbon is larger, leads to galvanic corrosion, which tries to bring down the durability of the FML. To bring down the effect of corrosion, a material layer is introduced between fibres and aluminium so as to separate them thus lowering the possibility of occurrence of corrosion. Another approach is to coat the surfaces of aluminium with different proportions of aluminium oxide nano particles prior to fabrication of the FML. For More >

  • Open Access

    ARTICLE

    EXPLORING SIMPLE MODELS FOR DRUG DELIVERY IN OCULAR DEVICES: DIFFUSION 1D, 2D AND EFFECT OF DRUG-POLYMER BINDING

    A.D.S.M.R. Pascoala , P.M. da Silvab,c, M.N.C. Coelho Pinheiroa,d,*

    Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-7, 2019, DOI:10.5098/hmt.12.29

    Abstract Efforts have been made to obtain new drug formulations in ophthalmologic applications to replace eye drops that are inefficient. Soft contact lenses have been using as an ophthalmic drug delivery device. Several hydrogels were used to prepare solid matrices with the drug impregnated. Assuming drug diffusion within polymeric devices as the dominant mechanism in the mass transfer process, simple models were developed to describe drug release from an ocular delivery device. The timolol maleate (medicine for glaucoma treatment) dissolution profile in the release medium for methacrylate hydrogels based contact lenses were obtained experimentally and compared More >

  • Open Access

    ARTICLE

    STUDY ON WAX DEPOSITION RATE OPTIMIZATION ALGORITHM BASED ON LEVENBERG-MARQUARDT ALGORITHM AND GLOBAL OPTIMIZATION

    Rongge Xiaoa , Yue Zhub,*, Wenbo Jina , Zheng Daia , Shifang Lia , Fan Zhangc

    Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-6, 2019, DOI:10.5098/hmt.12.28

    Abstract In order to accurately obtain the wax deposition rate model, according to the kinetic principle of wax deposition, several factors affecting the wax deposition rate were selected, and by a optimization software of First Optimization(1stOpt), The parameters of two typical wax deposition rate models are solved respectively based on optimization algorithm combined by Levenberg-Marquardt (L-M) algorithm and global optimization and the calculated data were compared. The results show that: compared with the model parameters obtained by least squares method, the model parameters obtained by this optimization algorithm can describe the variation of wax deposition rate… More >

  • Open Access

    ARTICLE

    NUMERICAL SIMULATION FOR INVERSE HEAT CONDUCTION PROBLEM OF SINGLE-LAYER LINING EROSION OF BLAST FURNACE

    Fuyong Sua,*, Rui Songa , Peiwei Nia , Zhi Wenb

    Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-5, 2019, DOI:10.5098/hmt.12.25

    Abstract A mathematical model of the inverse heat transfer problem of blast furnace lining is established in this study. Following the identification of the boundary conditions of the model, the inverse problem via the conjugate gradient method was decomposed into three issues: the direct problem, the sensitivity problem, and the adjoint problem. The feasibility of the model was verified through two types of real inner wall boundary shape functions. The effects of the initial inner wall boundary shape function and the number of measuring points are also investigated. Results showed that the accuracy of the inverse More >

  • Open Access

    ARTICLE

    THE EFFECTS OF GAP SPACING RATIO ON FLOW STRUCTURE AND HEAT TRANSFER CHARACTERISTIC FOR THE V-ORIFICE IN THE SQUARE CHANNEL HEAT EXCHANGER

    Amnart Boonloia, Withada Jedsadaratanachaib,*

    Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-13, 2019, DOI:10.5098/hmt.12.19

    Abstract The variations of flow and heat transfer in the square channel heat exchanger inserted with various parameters of V-orifice are investigated numerically. The influences of flow directions (V-Downstream and V-Upstream), gap spacing ratios (g/H or GR = 0, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) and blockage ratios (b/H or BR = 0.05, 0.10, 0.15, 0.25 and 0.30) on flow topology and heat transfer behavior are reported. The laminar flow regime with the Reynolds number in the range 100 – 2000 is considered. The numerical results are presented in terms of flow and heat transfer More >

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