Miscibility Evaluation of LDPE/EVA Blends Filled with Lignin by Rheological Properties and FT-IR

Lignin, one kind of byproduct of pulp-making industry, is used for the preparation of blends with LDPE/EVA by torque rheometer through the measuring maximal torque, balanced torque and plasticized time to confirm the optimum processing conditions. The miscibility, which is mainly dependent on the occurrence of lignin-polymer interactions of hydrogen bond, is characterized by Fourier infrared spectroscopic analysis (FT-IR). The results indicate that the rheological properties of lignin filled blends with 50~55N•maximal torque, 11~12N•m balanceable torque and 60~70s plasticized time are obtained under the conditions of 20 parts lignin blending with the LDPE and EVA proportion of 55/45 with 10 parts compatibilizer at 150°C. The FT-IR figures show that the hydrogen bond between compatibilizer and lignin or polymer is formed resulting from that the characteristic absorption peak of carbonyl at 1725~1800cm-1 disappears and hydroxide at 3438~3440cm-1 increases.

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Research Strategy for the HPLC/FT-IR Analysis of Drug Metabolites

Applied Spectroscopy ◽

10.1366/0003702971941151 ◽

1997 ◽

Vol 51 (6) ◽

pp. 866-873 ◽

Cited By ~ 5

Author(s):

D. E. Pivonka ◽

K. M. Kirkland

Keyword(s):

Spectroscopic Analysis ◽

Research Strategy ◽

Solution Phase ◽

Drug Metabolites ◽

Infrared Spectroscopic Analysis ◽

On Line ◽

Ft Ir ◽

Complementary Nature ◽

Ir Analysis ◽

Primary Focus

A strategy for the infrared spectroscopic analysis of drug metabolites in high-pressure liquid chromatography (HPLC) effluent is presented with a primary focus on delivery of metabolite structure as opposed to development of dedicated or automated instrumentation. This paper stresses the complementary nature of on-line (solution phase) and off-line (condensed phase) HPLC Fourier transform infrared (FT-IR) implementations for structural elucidation of drug metabolites.

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Etherifying Modification of Xylan-Type Hemicellulose and its Characterization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.1060 ◽

2013 ◽

Vol 821-822 ◽

pp. 1060-1064

Author(s):

Hai Ming Li ◽

Xiao Hong Chen ◽

Jing Hui Zhou ◽

Ying Han ◽

Guang Wei Sun

Keyword(s):

Zeta Potential ◽

Charge Density ◽

Spectroscopic Analysis ◽

Water Soluble ◽

Infrared Spectroscopic Analysis ◽

One Step ◽

Density Analysis ◽

Ft Ir ◽

Zeta Potential Analysis ◽

Thermal Stability Of

The reaction of the xylan-type hemicellulose with 2,3-epoxypropyltrimethylammonium chloride and acrylamide in ethanol-water-alkali slurry yielded water-soluble, cationic etherified xylan-type hemicellulose derivatives. The degree of substitution (DS) value reaches up to 0.40 by adjusting the mass ratios (NaOH/hemicellulose, total etherifying agents/hemicellulose and 2,3-epoxypropyltrimethylammonium chloride/acrylamide), the reaction temperature and the reaction time in a one-step synthesis. The etherified hemicellulose was characterized by infrared spectroscopic analysis (FT-IR), Zeta potential analysis, charge density analysis and thermogravimetric analysis (TGA). It is found that Zeta potential is promoted from-30.50mv to +35.81mv and charge density is promoted from-0.50mmol/g to +0.88mmol/g during etherification under the conditions used. The thermal stability of the etherified hemicellulose is lower than that of the unmodified xylan-type hemicellulose polymers.

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Polyacrylic Acid Modified Cerium Oxide Nanoparticles: Synthesis and Characterization as a Peroxidase Mimic for Non-Enzymatic H2O2 Sensor

Current Nanoscience ◽

10.2174/1573413715666191204124329 ◽

2020 ◽

Vol 16 (5) ◽

pp. 816-828

Author(s):

Gurdeep Rattu ◽

Nishtha Khansili ◽

Prayaga M. Krishna

Keyword(s):

Hydrogen Peroxide ◽

Cerium Oxide ◽

Polyacrylic Acid ◽

Spectroscopic Analysis ◽

Cerium Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Peroxidase Mimic ◽

Ft Ir ◽

H2o2 Sensing ◽

Fluorescence Spectrometer

Background: Cerium oxide nanoparticles (nanoceria) are efficient free-radical scavengers due to their dual valence state and thus exhibit optical and catalytic properties. Therefore, the main purpose of this work was to understand the peroxidase mimic activity of polymer-stabilized nanoceria for enzyme-less H2O2 sensing by fluorescence spectrometer. Objective: This research revealed the development of fluorescence hydrogen peroxide nanosensor based on the peroxidase-like activity of polyacrylic acid stabilized nanoceria (PAA-CeO2 Nps). Methods: PAA-CeO2 Nps were synthesized by simple cross-linking reaction at a low temperature and characterized by XRD, SEM, Zeta potential, TGA, FT-IR and UV-VIS spectroscopic analysis. H2O2 sensing was performed by a fluorescence spectrometer. Results:: The synthesized polymer nanocomposite was characterized by XRD, SEM, TGA, FT-IR and UV-VIS spectroscopic analysis. The XRD diffraction patterns confirmed the polycrystalline nature and SEM micrograph showed nanoparticles having hexagonal symmetry and crystallite size of 32 nm. The broad peak of Ce–O bond appeared at 508 cm-1. UV-VIS measurements revealed a welldefined absorbance peak around 315 nm and an optical band-gap of 3.17 eV. As synthesized PAACeO2 Nps effectively catalysed the decomposition of hydrogen peroxide (H2O2) into hydroxyl radicals. Then terephthalic acid was oxidized by hydroxyl radical to form a highly fluorescent product. Under optimized conditions, the linear range for determination of hydrogen peroxide was 0.01 - 0.2 mM with a limit of detection (LOD) of 1.2 μM. Conclusion: The proposed method is ideally suited for the sensing of H2O2 at a low cost and this detection system enabled the sensing of analytes (sugars), which can enzymatically generate hydrogen peroxide.

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