A Comparative Study of the Structure and Properties of Certain Types of Oligodiene

2018 ◽  
Vol 45 (1) ◽  
pp. 27-30
Author(s):  
N.A. Shabunina ◽  
V.D. Voronchikhin ◽  
E.I. Lesik ◽  
A.V. Berestyuk ◽  
O.V. Karmanova ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Ir Spectroscopy ◽  
Gel Permeation Chromatography ◽  
Molecular Characteristics ◽  
Structure And Properties ◽  
Gel Permeation ◽  
Temperature Dependences ◽  
Infrared Spectrometer ◽  
Processing Properties ◽  
Rotary Viscometer

Using methods of IR spectroscopy (Fourier infrared spectrometer; PerkinElmer) and gel permeation chromatography (Agilent 1200; Agilent Technologies), we studied the microstructure and molecular characteristics of four types of diene oligomer (DO) of different functionality. The dynamic viscosity, η, of DOs was measured on a rotary viscometer (LVDV-II + Pro; Brookfield). A comparative analysis of the obtained results makes it possible to predict the dispersion and the plasticising effect of DOs in polymer–oligomer composites. The temperature dependences of η for different DOs differ in the temperature range 20–60°C; at temperatures of 80°C and above, the values of h are practically identical, i.e. their processing properties are the same, and the replacement of one DO with another will not lead to any need to alter the processing regime of the composites.

Selective modification of polylactide by introducing acrylate groups: IR spectroscopy, gel permeation chromatography, and differential thermal analysis

2016 ◽  
Vol 90 (10) ◽  
pp. 1925-1930 ◽  
Author(s):  
V. T. Shashkova ◽  
I. A. Matveeva ◽  
N. N. Glagolev ◽  
T. S. Zarkhina ◽  
P. S. Timashev ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Ir Spectroscopy ◽  
Gel Permeation Chromatography ◽  
Gel Permeation

Study on Synthesis and Properties of Phenols Polymer Syntan Catalyzed by Enzyme

2011 ◽  
Vol 138-139 ◽  
pp. 1072-1077
Author(s):  
Sheng Hua Lv ◽  
Rui Gong ◽  
Yan Fen Ma
Keyword(s):  
Molecular Weight ◽  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Average Molecular Weight ◽  
Gel Permeation Chromatography ◽  
Molar Ratio ◽  
Structure And Properties ◽  
Monomer Composition ◽  
Gel Permeation

A phenolic copolymer was synthesized from resorcinol (RSC) and 3,5-dihydroxy benzoic acid (DBA) using horseradish peroxidase (HRP)/H2O2 as the radical copolymerization’s initiateor. It was discussed that the effects of monomer composition on the properties of the copolymer. The best molar ratio was 1:1. The structure and properties of the copolymer was characterized by Fourier Transform Infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance (HNMR), Molecular weight (MW) was determined by gel permeation chromatography (GPC). The result shows that the average molecular weight of the copolymer is about 40000. The effect of dosage of HRP on the properties of the copolymer was investigated. And the mechanism of polymerization of RSC and DBA was advanced. The copolymer was used as tanning agent, applied results show that it has excellent retanning properties. It was realized the applicatiom of HRP on the phenols syntan.

SYNTHESIS OF POLY[(ε-CL)-co-(GA-alt-L-Asp)] COPOLYMER AND EFFECTS ON CELLS AFTER COUPLING WITH SMALL PEPTIDE

2015 ◽  
Vol 27 (06) ◽  
pp. 1550053
Author(s):  
Na Qiang ◽  
Fang Xie ◽  
Hao Liang ◽  
Xian-Feng Li ◽  
Shuo Tang ◽  
...  
Keyword(s):  
Ring Opening ◽  
Gel Permeation Chromatography ◽  
Ring Opening Polymerization ◽  
Carboxyl Groups ◽  
Structure And Properties ◽  
Small Peptide ◽  
Scanning Calorimetry ◽  
Beneficial Effects ◽  
Structural Regularity ◽  
Gel Permeation

A novel poly[([Formula: see text]-CL)-co-(GA-alt-L-Asp)] with improved hydrophilicity was prepared. The monomer 3(S)-[(benzyloxycarbony)methyl]-1,4-dioxane-2,5-dione (BMD) was prepared from aspartic acid. The polymer was obtained by ring-opening polymerization of [Formula: see text]-caprolactone ([Formula: see text]-CL) and BMD. Poly[([Formula: see text]-CL)-co-(GA-alt-L-Asp)] was synthesized by deprotection. The structure and properties of the polymer were characterized using 1H nuclear magnetic resonance, gel permeation chromatography, and differential scanning calorimetry. The melting point and melting enthalpy of the polymer decreased with the increase of BMD. The structural regularity of polycaprolactone was destroyed by the BMD. A laminin-derived peptide [i.e., Arg-Gly-Asp (RGD)] was covalently tethered to the carboxyl groups and the peptide-grafted films. Results indicated that the addition of RGD had beneficial effects for cell growth, as shown by scanning electron microscopy.

Effect of Low Molecular Weight Ethylene Homopolymer on Structure and Properties of Bimodal High Density Polyethylene

2012 ◽  
Vol 217-219 ◽  
pp. 603-608
Author(s):  
Xing Bo Shi ◽  
Ju Lin Wang ◽  
Xiao Ping Cai
Keyword(s):  
Molecular Weight ◽  
High Density Polyethylene ◽  
Gel Permeation Chromatography ◽  
High Density ◽  
Low Molecular Weight ◽  
Structure And Properties ◽  
Scanning Calorimetry ◽  
Processing Properties ◽  
Positive Effect ◽  
Properties Of Composites

The effect of low molecular weight (LMW) ethylene homoploymer on the structure and properties of bimodal high density polyethylene (HDPE) was studied by blending two commercial bimodal HDPE resins (tandem reactor) with two types of LWM ethylene homopolymer. The molecule weight and molecule weight distribution, crystsallinity, rheological and mechanical properties of composites were characterized by high temperature gel permeation chromatography (HT-GPC), differential scanning calorimetry (DSC), capillary rheometer respectively. For composites of bimodal HDPE and LMW ethylene homopolymer, the polydispersity index (PDI) and crystallinity can be effectively increased when reduce the molecular weight of first reactor in tandem reactor. The viscosity of composites decreases at high shear rate. Increasing of LMW component has a positive effect on processing properties and tensile strength, while makes composites brittle.

Analysis of the molecular characteristics of crosslinked systems by gel-permeation chromatography

1989 ◽  
Vol 31 (3) ◽  
pp. 654-660
Author(s):  
N.A. Domnicheva ◽  
S.I. Kogan ◽  
V.A. Kuznetsova ◽  
A.Ya. Sorokin ◽  
V.P. Budtov
Keyword(s):  
Gel Permeation Chromatography ◽  
Molecular Characteristics ◽  
Gel Permeation

scholarly journals Molecular Characteristics and Antioxidant Activity of Spruce (Picea abies) Hemicelluloses Isolated by Catalytic Oxidative Delignification

Molecules ◽  
2022 ◽  
Vol 27 (1) ◽  
pp. 266
Author(s):  
Valentina S. Borovkova ◽  
Yuriy N. Malyar ◽  
Irina G. Sudakova ◽  
Anna I. Chudina ◽  
Andrey M. Skripnikov ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Thermogravimetric Analysis ◽  
Gel Permeation Chromatography ◽  
Molecular Characteristics ◽  
Average Molar Mass ◽  
Composition And Structure ◽  
Gel Permeation ◽  
Acetic Acid Water ◽  
Physicochemical Methods ◽  
Oxidative Delignification

Spruce (Piceaabies) wood hemicelluloses have been obtained by the noncatalytic and catalytic oxidative delignification in the acetic acid-water-hydrogen peroxide medium in a processing time of 3–4 h and temperatures of 90–100 °C. In the catalytic process, the H2SO4, MnSO4, TiO2, and (NH4)6Mo7O24 catalysts have been used. A polysaccharide yield of up to 11.7 wt% has been found. The hemicellulose composition and structure have been studied by a complex of physicochemical methods, including gas and gel permeation chromatography, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. The galactose:mannose:glucose:arabinose:xylose monomeric units in a ratio of 5:3:2:1:1 have been identified in the hemicelluloses by gas chromatography. Using gel permeation chromatography, the weight average molar mass Mw of hemicelluloses has been found to attain 47,654 g/mol in noncatalytic delignification and up to 42,793 g/mol in catalytic delignification. Based on the same technique, a method for determining the α and k parameters of the Mark–Kuhn–Houwink equation for hemicelluloses has been developed; it has been established that these parameters change between 0.33–1.01 and 1.57–472.17, respectively, depending on the catalyst concentration and process temperature and time. Moreover, the FTIR spectra of the hemicellulose samples contain all the bands characteristic of heteropolysaccharides, specifically, 1069 cm−1 (C–O–C and C–O–H), 1738 cm−1 (ester C=O), 1375 cm−1 (–C–CH3), 1243 cm−1 (–C–O–), etc. It has been determined by the thermogravimetric analysis that the hemicelluloses isolated from spruce wood are resistant to heating to temperatures of up to ~100 °C and, upon further heating, start destructing at an increasing rate. The antioxidant activity of the hemicelluloses has been examined using the compounds simulating the 2,2-diphenyl-2-picrylhydrazyl free radicals.

scholarly journals Functionalization of polyolefins by reactive processing

2003 ◽  
Vol 1 (3) ◽  
pp. 277-290 ◽  
Author(s):  
A. Zelenetskii ◽  
V. Volkov ◽  
N. Artem’eva ◽  
M. Sizova ◽  
V. Nikol’skaya ◽  
...  
Keyword(s):  
Solid State ◽  
Maleic Acid ◽  
Polymeric Materials ◽  
Gel Permeation Chromatography ◽  
Molecular Characteristics ◽  
Reactive Processing ◽  
Intermolecular Association ◽  
System Components ◽  
Gel Permeation ◽  
Sodium Maleate

AbstractFrom the study of the modification of PE and PP with maleic anhydride, maleic acid and an acid salt of maleic acid (sodium maleate) in a liquid or solid state, it was shown that the main controlling factor in the solid state modification of polyolefins is the joint plastic deformation of the system components. The changes of molecular characteristics were investigated by gel permeation chromatography. It was shown, that the molecular weight of modified PP samples increases at times by linking with intermolecular associates in the solutions. The formation of associates plays essential role in the behaviour of solutions of modified PP. The morphology of modified PP samples was investigated by scanning electron microscopy. It was shown, that intermolecular association strongly influences on the processes of formation and growth of nucleus and the structure of generated polymeric materials.

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