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Showing posts with the label Organic photonics

Elution Dynamics of Adsorption: Comparing the Solutions of Direct and Inverse Problems

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   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Studies of the elution dynamics of adsorption have revealed a close correspondence between the analytical solutions to (i) a direct problem formulated using an equilibrium adsorption layer model and (ii) an inverse problem formulated using the method of moments. Keywords:  Elution Dynamics; Adsorption; Charcoal; chromatograph; Numerical Equations Introduction The effects of adsorption dynamics on the elution peak profile for an arbitrary adsorption isotherm were previously analyzed in [1] using numerical simulations based on a model that assumed a layer of equilibrium adsorption (LEA model) [2]. Assuming linear adsorption dynamics, [1] revealed that the elution curves simulated using the LEA model agreed well with experimental data obtained for a given integer unit of relative adsorbent bed length (n). The solution parameters to the inverse problem, formulated using the method of moments for intege...

Favorite yet a Carcinogenic and Neuro-Reactive Monomer “Acrylamide”: Formation in Food, Consumption and Health Impacts

     JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Acrylamide is a monomer which is associated with asparagine especially when proteins react to carbohydrate during Maillard reaction. The issue of this carcinogen was highlighted by Swedish Nation Food Administration SNFA and the cause progressed by European food industries, especially spiked the high treatment to high saccharon foods. Experiments replicated to find end products of trio effects of high saccharides, free protein subunits the aminoacids and high temperature, revealing formation of acrylamide in research institutes and snack food industries. Mini review highlights formation, consumption, and health impacts of acrylamide. Keywords:  Acrylamide; Carcinogen; Processed Foods; Sugars; Maillard Reaction Abbreviations:  Swedish Nation Food Administration (SNFA); Food Standards Agency (FSA); Scientific Committee on Food (SCF) Introduction Acrylamide is a cancer causing precurser an...

Effect of the Polyethyleneimine Coating on the Bending Properties of the Natural Fiber-Reinforced Biocomposites

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   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract In the scope of this study woven flax fibers are coated with aqueous polyethyleneimine (PEI) solution, in order to improve the bending properties of the produced flax fiber-reinforced epoxy composite. The textiles are coated with the different concentrations of PEI solution and integrated into the biobased epoxy using hand impregnation with subsequent hot-press. The results show that 1 wt% and 5 wt% PEI can considerably improve the bending properties of the tested biocomposites. Keywords:  Natural Fibers; Polyethyleneimine; Biocomposites; Surface Treatments Introduction Cellulose-based fiber composites have already approved their beneficial performance in the fields of automotive (interior) and sport and leisure [1,2]. Compared with synthetic fiber-reinforced composites, biocomposites containing cellulose-based natural fibers as a reinforcement offer numerous material specific advantages, like e.g....

Excited Triplet States of Organic Molecules and Reactive Free Radicals in Polymers

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     JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract The mini-review is devoted to the recent investigation the role of cage effect during photopolymerization. Benzophenone was selected as a photoinitiator of polymerization. Introduction Free-radical photopolymerization (UV-cure) of organic coatings is a very important process that has been used for more than half a century. Academic and industrial researchers study the basics of this complex process [1-4] In this mini review we will briefly consider the important role of low MW free radicals of photoinitiators (PIs) and the excited triplet states of PIs in photopolymerization. On the contrary, residual PIs in the cured coatings and other low MW photoreactive species in the cured coatings/polymers lead to a negative effect: photodecomposition of polymers outdoors, poor weatherability. We will comment on that as well. Discussion A primary chemical act of free radical photopolymerization is the gener...

Synthesis and Radical Copolymerization of Novel Phenyl-Disubstituted Propyl Cyanoacrylates-Juniper Publishers

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   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Novel phenyl-disubstituted propyl 3-(R-phenyl)-2-cyanoacrylates, RPhCH=C(CN)CO 2 C 3 H 7  (where R is 2-fluoro-5-methyl, 3-iodo-4-methoxy, 5-iodo-2-methoxy, 3,5-dichloro, 3,4-difluoro, 3,5-difluoro, 2-chloro-4-fluoro, 2-chloro-6-fluoro, 3-chloro-2-fluoro, and 3-chloro-4-fluoro) were prepared using condensation of substituted benzoic aldehydes and propyl ester of cyanoacetic acid. The ethynyl benzene copolymerization of novel cyanoacrylates was conducted in solution with radical initiation at 70 C. Nitrogen analysis,  1 H &  13 C NMR was used to analyze composition and the structure. Thermal behavior of the copolymers was analyzed by DSC and TGA. Keywords:  Radical copolymerization; Styrene copolymers; Trisubstituted ethylene’s; Cyanoacrylates Introduction Ring–functionalized trisubstituted ethylene’s (TSE), esters of 3-phenyl-2-cyanoacrylates, R1PhCH=C(CN) CO 2 R 2  continu...