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  • Open Access

    ARTICLE

    Copolymerization of 5-[4-(methacryloylamino)phenyl]- l0,15, 20-triphenylporphyrin with Styrene: Investigation of Spectroscopic, Structural and Thermal Properties

    FEHMI SALTAN1,2, AYLIN PALAMUTLU2, HAKAN AKAT2,*

    Journal of Polymer Materials, Vol.36, No.2, pp. 133-147, 2019, DOI:10.32381/JPM.2019.36.02.3

    Abstract In this work, tetraphenylporphyrin (TPP) compound was first synthesized by the condensation reaction of pyrrole and benzaldehyde using Adler method. Then, the synthesized tetraphenylporphyrin was nitrated with sodium nitrite. Nitro-functionalized porphyrin (TPP-NO2 ) compound was reduced to amine-functional using ammonia and this amine- functionalized porphyrin was reacted with methacryloyl chloride to obtain porphyrin-derived radical monomer (TPP-MAO). Copolymer was synthesized with obtained porphyrin functional monomer and styrene by free radical polymerization method. Structural characterization and spectroscopic studies of the synthesized compounds were carried out by FTIR, H1 -NMR, UV spectroscopy. The molecular weight and thermal properties of More >

  • Open Access

    ARTICLE

    Synthesis and Characterization of Epoxy Resin of (2E, 6E) - Bis (4-hydroxybenzylidene) -4-methylcyclohexanone

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

    Journal of Polymer Materials, Vol.36, No.1, pp. 101-109, 2019, DOI:10.32381/JPM.2019.36.01.8

    Abstract The epoxy resin (EMBHBC) of (2E,6E)-bis (4-hydroxybenzylidene)-4-methyl cyclohexanone (MBHBC) was synthesized by condensing 0.5 mol MBHBC and 2.5 mol epichlorohydrin in 500 mL isopropyl alcohol as a solvent and 1.0 mol NaOH in 50 mL water as a catalyst at 80°C for 3 h. The structure of EMBHBC was supported by UV-Vis, FTIR, 1 HNMR and 13CNMR spectroscopic techniques. Molecular weights and molecular weight distribution of EMBHBC were determined by gel permeation chromatography. DSC thermogram of EMBHC showed one endothermic transition (95.9°C) and two exothermic transitions (317.7°C and 382.2°C) due to melting and decomposition transitions, respectively. More >

  • 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

    Preparation and Characterization of Carbon Microspheres From Waste Cotton Textiles By Hydrothermal Carbonization

    Yongfang Zhang1,2, Wensheng Hou1, Hong Guo1, Sheng Shi1, Jinming Dai1,2,*

    Journal of Renewable Materials, Vol.7, No.12, pp. 1309-1319, 2019, DOI:10.32604/jrm.2019.07884

    Abstract Carbon microspheres were prepared from waste cotton fibers by hydrothermal carbonization (HTC) with the addition of copper sulphate in this work. The important influence factors, temperature, concentration of copper sulphate, resident time were explored here. The smooth and regular carbon microspheres could be formed at 330°C with 0.15 wt% copper sulphate after 6 h from waste cotton fibers. The crystal structures of cotton fibers were destructed in a short resident time with 0.15 wt% copper sulphate from SEM images and XRD patterns of solid products. This strategy provides a new, mild and efficient method to… More >

  • Open Access

    ABSTRACT

    Biomechanical Characterization of Mouse Sclera in Myopia

    C. Ross Ethier1,*, Dillon M. Brown1, Erica Landis2, Machelle T. Pardue1,2,3

    Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 61-63, 2019, DOI:10.32604/mcb.2019.07377

    Abstract Myopia, or near-sightedness, is a common ocular condition in which the eye elongates excessively. Development of myopia is associated with, and thought to be facilitated by, changes in the biomechanical properties of the sclera (the white part of the eye). We characterized scleral biomechanics in a mouse model of myopia using unconfirmed compression testing and biphasic theory to extract scleral permeability, in- plane scleral tensile modulus, and through-plane scleral compressive modulus. We find that myopia reduces in-plane tensile modulus and permeability, consistent with scleral tissue remodeling. Such biomechanical outcome measures may offer advantages over more More >

  • Open Access

    ABSTRACT

    Mechanics Based Tomography Using Camera Images

    Sevan Goenezen1,*, Ping Luo1, Baik Jin Kim1, Maulik Kotecha1, Yue Mei2,3

    Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 46-48, 2019, DOI:10.32604/mcb.2019.07348

    Abstract It is well known that the mechanical properties of tissues may vary spatially due to changing tissue types or due to inherent tissue disease. For example, the biomechanical properties are known to vary throughout blood vessels [1]. Diseases such as cancers may also lead to locally altered mechanical properties, thus allow a preliminary diagnosis via finger palpation. Quantifying the mechanical property distribution of tissues for a given constitutive equation will allow to characterize the biomechanical response of tissues. This may help to 1) predict disease progression, 2) diagnose diseases that alter the biomechanics of the… More >

  • Open Access

    ABSTRACT

    Comparison of the Virtual Fields Method and the Optimization Method to Characterize Regional Variations in Material Properties of Soft Tissues

    Yue Mei1,2,3, Stephane Avril3,*

    Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 44-44, 2019, DOI:10.32604/mcb.2019.07034

    Abstract Characterizing regional variations of material properties in soft tissues is essential for biomedical engineering and clinical medicine, including but not limited to cancerous disease detection and patient-specific surgical planning of cardiovascular diseases. Identification of nonhomogeneous material property distribution usually requires solving inverse problems in nonlinear elasticity. Generally, inverse algorithms can be categorized into two groups: iterative inversion and direct inversion. In direct inversion, the material property distribution of soft tissues is estimated directly from the equilibrium equations, while the inverse problem is posed as an optimization problem in iterative inversion. In this presentation, we compare… More >

  • Open Access

    ABSTRACT

    Characterization of Coronary Atherosclerotic Plaque Composition Based on Convolutional Neural Network (CNN)

    Yifan Yin1, Chunliu He1, Biao Xu2, Zhiyong Li1,*

    Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 57-57, 2019, DOI:10.32604/mcb.2019.05732

    Abstract The tissue composition and morphological structure of atherosclerotic plaques determine its stability or vulnerability. Intravascular optical coherence tomography (IVOCT) has rapidly become the method of choice for assessing the pathology of the coronary arterial wall in vivo due to its superior resolution. However, in clinical practice, the analysis of plaque composition of OCT images mainly relies on the interpretation of images by well-trained experts, which is a time-consuming, labor-intensive procedure and it is also subjective. The purpose of this study is to use the Convolutional neural network (CNN) method to automatically extract the best feature… More >

  • Open Access

    ABSTRACT

    Mechanical Characterization and Constitutive Modeling of Rabbit Aortas in Health and Diabetes

    Zhi Zhang1, Jianhua Tong1,*

    Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 43-43, 2019, DOI:10.32604/mcb.2019.05721

    Abstract Diabetes is a major risk factor to cause macrovascular diseases and plays a pivotal role in aortic wall remodeling. However, the effects of diabetes on elastic properties of aortas remain largely unknown. Thirty adult rabbits (1.6-2.2 kg) were collected and the type I diabetic rabbit model was induced by injection of alloxan. A total of 15 control and 15 diabetic rabbit (abdominal) aortas were harvested. Uniaxial and biaxial tensile tests were performed to measure ultimate tensile strength and to characterize biaxial mechanical behaviors of the aortas. A material model was fitted to the biaxial experimental… More >

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