Effects of added phthalate plasticizers on photodegradation of irradiated poly (α-methylstyrene) films

2015 ◽  
Vol 35 (2) ◽  
pp. 159-167 ◽  
Author(s):  
Afrah E. Ramadhan
Keyword(s):  
Dibutyl Phthalate ◽  
Irradiation Time ◽  
Broad Band ◽  
Dioctyl Phthalate ◽  
Solid Films ◽  
Polymeric Chains ◽  
Ft Ir ◽  
The Stability ◽  
Monomer Fluorescence ◽  
Ft Ir Spectroscopy

Abstract The effects of UV irradiation and blending on the stability of poly (α-methylstyrene) (PαMS) in solid films were studied at different intervals of irradiation time in the presence of air, by absorption, emission and Fourier transform infrared (FT-IR) spectroscopy. The increase in irradiation time caused an increase in the intensity of the absorption band of the polymer, and an increase in the intensity of absorption of a new broad band at a longer wavelength, thus indicating the possibility of photodegradation of polymeric chains. The influence of added plasticizers, dimethyl terephthalate (DMT), diethyl terephthalate (DET), dibutyl phthalate (DBP), dioctyl phthalate (DOP) and dioctyl terephthalate (DOT) on photoquenching of the polymer fluorescence band was also investigated, and found to increase the photoquenching processes with increase in the amount of added plasticizers. By contrast, the intensity of excimer and monomer fluorescence bands was also found to decrease with increase in irradiation times. These changes may be attributed to the formation of new photoproducts which resulted from the photodegradation and photooxidation of irradiated polymeric chains. In addition, the observed increase in the intensities of the carbonyl and hydroxyl regions of the FT-IR spectra provides evidence for the photooxidation of polymeric chains. The increase in the intensity of some bands and the disappearance of new bands indicate the photodegradation of polymeric chains.

scholarly journals Irradiation Effect on Stability of Plasticized Poly(Fluorostyrene) Isomers in Solution

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Khalid E. Al Ani ◽  
Afrah Essa Ramadhan ◽  
Mai Anabtawi
Keyword(s):  
Absorption Band ◽  
Irradiation Time ◽  
Broad Band ◽  
Dioctyl Phthalate ◽  
The Other ◽  
Irradiation Effect ◽  
Polymeric Chains ◽  
Monomer Fluorescence ◽  
Polarity Of Solvents ◽  
Considerable Enhancement

The UV irradiation and blending effects on stability of Poly(Fluorostyrene) isomers in solution were studied at different intervals of irradiation time in presence of air. The increase in irradiation time of these isomers caused an increase in the intensity of the absorption band and an increase in the intensity of the absorption of new broad band at longer wavelength, thus indicating a possibility of photodegradation of polymeric chains. The influence of added dioctyl phthalate and dioctyl terephthalate plasticizers on photooxidative degradation was also investigated and was found to increase the photodegradation processes in polymeric chains. On the other hand, the intensity of excimer and monomer fluorescence bands maxima was also found to decrease with increase in irradiation times. These changes may be attributed to the formation of new photoproducts resulted from the photodegradation of irradiated polymeric chains. The decrease in polarity of used solvents caused a considerable enhancement to the intensity of the polymer fluorescence band and accelerated photodegradation. A proposed mechanism is suggested to account for the effects of added plasticizers, the increase in irradiation time, and polarity of solvents on photodegradation and photooxidation processes in polymeric chains.

Study on Host-Guest Inclusion Complexation of a Drug in Cucurbit [6]uril

2018 ◽  
Vol 232 (2) ◽  
pp. 281-293 ◽  
Author(s):  
Kanak Roy ◽  
Subhadeep Saha ◽  
Biswajit Datta ◽  
Lovely Sarkar ◽  
Mahendra Nath Roy
Keyword(s):  
Surface Tension ◽  
Specific Conductivity ◽  
Inclusion Complexation ◽  
Conductivity Measurements ◽  
Saline Environment ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
The Stability ◽  
Ft Ir Spectroscopy

AbstractAssembly of pyridine-2-aldoxime drug with cucurbit [6]uril (CB[6]) has been investigated by1H-NMR and 2D-ROESY NMR, UV-Vis spectroscopy, FT-IR spectroscopy, surface tension and conductivity measurements in aqueous saline environment. The distinct cationic receptor feature and the cavity dimension of the CB[6] emphasize that the macro-cyclic host molecule remain as complex with the nerve stimulus drug molecule. The results obtained from surface tension and specific conductivity measurements suggest 1:1 inclusion complex formation between drug and CB[6]. The stability constant evaluated by UV-Vis spectroscopic approach is 2.21×105M−1at 298.15 K, which indicates that the complex is sufficiently stable at physiological temperature.

Synthesis of Posnjakite Nanoparticles in the Presence of a New Capping Agent

2016 ◽  
Vol 35 (5) ◽  
pp. 457-462 ◽  
Author(s):  
Mehdi Bazarganipour ◽  
Mahnaz Sahebi-Harandi ◽  
Masoud Salavati-Niasari
Keyword(s):  
Microwave Power ◽  
Irradiation Time ◽  
Heating Time ◽  
Molar Ratio ◽  
Capping Agent ◽  
X Ray Diffraction ◽  
X Ray ◽  
Methylene Orange ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

AbstractPosnjakite nanoparticles, Cu4SO4(OH)6 · H2O, were synthesized by utilizing a new thio-Schiff base ligand as new capping agent via a microwave approach. The effects of molar ratio, surfactants, heating time and microwave power on morphology of the product were investigated. The as-synthesized posnjakite nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and energy dispersive X-ray analysis (EDAX). The effects of different parameters such as the molar ratio, surfactants, microwave power and irradiation time on the morphology of the products were investigated. Moreover, adsorption of methylene orange dye on posnjakite nanoparticles was considered and the uptake percent was determined to be >65% in 200 min.

Self-cleaning effect of electrospun poly (1,4-cyclohexanedimethylene isosorbide terephthalate) nanofibers embedded with zinc oxide nanoparticles

2017 ◽  
Vol 88 (21) ◽  
pp. 2493-2498 ◽  
Author(s):  
Muhammad Qamar Khan ◽  
Hoik Lee ◽  
Jun Mo Koo ◽  
Zeeshan Khatri ◽  
Jianhua Sui ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Zinc Oxide ◽  
Zno Nanoparticles ◽  
Irradiation Time ◽  
Cleaning Efficiency ◽  
Transmission Electron ◽  
Uniform Dispersion ◽  
Ft Ir ◽  
Self Cleaning ◽  
Ft Ir Spectroscopy

This study examined the photocatalytic self-cleaning of novel nanofibers of co-polyester poly(1,4-cyclohexanedimethylene isosorbide terephthalate) (PICT). To obtain the self-cleaning property, zinc oxide (ZnO) nanoparticles were blended into the solution of PICT at five different concentrations. The morphology of the nanofibers was analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the degradation spectrum of the target dyes was confirmed by Fourier Transform Infrared (FT-IR) spectroscopy. Especially in the TEM images, there was clear evidence of a uniform dispersion of the ZnO nanoparticles embedded in the nanofibers. As the concentration of ZnO increased to 9 wt%, there was a greater dispersion of the ZnO nanoparticles on the nanofibers. The photocatalytic activity indicated that more efficient self-cleaning occurred at an irradiation time of 3 hours and a 9% concentration of ZnO nanoparticles in the nanofibers. We achieved around 99% self-cleaning efficiency from these nanofibers.

DLC-coated Substrate for Infrared Absorption Spectroscopy in Supercritical Water

2011 ◽  
Vol 1309 ◽  
Author(s):  
Takuji Ube ◽  
Takashi Ishiguro
Keyword(s):  
Ir Spectroscopy ◽  
Zinc Selenide ◽  
Supercritical Water ◽  
Fused Silica ◽  
Diamond Like Carbon ◽  
Infrared Absorption Spectroscopy ◽  
Coated Substrate ◽  
Ft Ir ◽  
The Stability ◽  
Ft Ir Spectroscopy

ABSTRACTThe stability of several kinds of substrates, such as Corning #1737 glass, fused silica, synthetic silica, water free synthetic silica, zinc selenide, silicon, and diamond like carbon (DLC) coated Si in supercritical water (663K and 25MPa) were examined. Their reaction with the water was evaluated by using Fourier transform infrared (FT-IR) spectroscopy. As a result of the present experiment, it was found that DLC-coated Si is one of the most stable and useful substrates for IR spectroscopy in supercritical water.

Article

1998 ◽  
Vol 76 (11) ◽  
pp. 1730-1736
Author(s):  
Mathew D Halls ◽  
Ricardo Aroca
Keyword(s):  
Ab Initio ◽  
Normal Modes ◽  
Light Emitting ◽  
Solid Films ◽  
Ft Ir ◽  
First Time ◽  
Mode Assignment ◽  
Transmission And Reflection ◽  
Ft Ir Spectroscopy

The vibrational spectra of one of the most commonly used light-emitting materials for organic electroluminescence (EL) devices, tris(8-hydroxyquinoline)aluminum (Alq3), is presented. The geometry and normal modes of fac-Alq3 isomer in the ground state have been computed for the first time using ab initio methods (HF/6-31G*) to aid in discussion of normal-mode assignment. Normal inelastic scattering excited at 633 nm and low-temperature FT-Raman in addition to the infrared spectra of this material are reported. The vibrational characterization of thin solid films of the material was attempted using transmission and reflection-absorption FT-IR spectroscopy (RAIRS) on smooth silver films.Key words: tris(8-hydroxyquinoline)aluminum, Alq3, ab initio, assignments, infrared, Raman, thin films.

Molecular Sieve Thin Films via Laser Ablation

1994 ◽  
Vol 351 ◽  
Author(s):  
Kenneth J. Balkus ◽  
Scott J. Riley ◽  
Bruce E. Gnade
Keyword(s):  
Thin Films ◽  
Laser Ablation ◽  
Molecular Sieves ◽  
Molecular Sieve ◽  
Film Formation ◽  
Aluminum Phosphate ◽  
Effective Technique ◽  
Solid Films ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

ABSTRACTLaser ablation has become widely recognized as an effective technique for the preparation of thin solid films. We have employed an excimer laser (KrF, 248 nm) to deposit well dispersed thin films of aluminum phosphate molecular sieves on a titanium nitride substrate. Results for the ablation of AIPO4-5, AIPO4-H3 and AIPO4-H1 molecular sieve targets are presented. The laser power and repetition rate as well as substrate distance and temperature affect the thin film formation. A subsequent hydrothermal post treatment of the ablated films was found to enhance the surface crystallinity. The molecular sieve thin films were characterized by XRD, SEM, XRF, and FT-IR spectroscopy.

Surface Modification of Alumina Nano-Particles by UV-Induced Grafting Polymerization of 2-Hydroxyethyl Methacrylate

2010 ◽  
Vol 93-94 ◽  
pp. 95-98 ◽  
Author(s):  
K. Yantaboot ◽  
S. Maensiri ◽  
Paveena Khansawai ◽  
Sittipong Amnuaypanich
Keyword(s):  
Uv Irradiation ◽  
Irradiation Time ◽  
Nano Particles ◽  
Hydroxyethyl Methacrylate ◽  
Alumina Surface ◽  
Sequential Method ◽  
Grafting Polymerization ◽  
Alumina Particles ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Alumina nano-particles was grafted with poly(2-hydroxyethyl methacrylate) (PHEMA) utilizing the sequential method; that is, the alumina surface was first rendered with initiator, benzophenone, by UV-irradiation followed by the grafting polymerization of HEMA on the surface which was initiated thermally and propagated via the free-radical polymerization. FT-IR spectroscopy confirmed the successful grafting of PHEMA onto the alumina surface. Determined by thermalgravimetry (TG), the amount of benzophenone on the alumina surface was found to increase with the UV-irradiation time; however upon grafting of PHEMA, the amount of grafted-PHEMA was the same irrespective of the reaction time. The glass transition temperature (Tg) of grafted-PHEMA on alumina particles was approximately 93 °C that is higher than that of PHEMA which has Tg around 85 °C. This indicates the more restricted movement of grafted-PHEMA compared with the ungrafted-PHEMA.

scholarly journals Synthesis, characterization of Ag-doped CdS-WO2 nanocomposite and effects of photocatalytic degradation in RhB under visible light irradiation

2022 ◽  
Author(s):  
G. Roshini ◽  
V. Sathish ◽  
S. Manigandan ◽  
A. Tamilarasi ◽  
E. Priyanka
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Photocatalytic Performance ◽  
Irradiation Time ◽  
Light Irradiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Abstract In this paper, the highly stable Ag/CdS-WO2 nanocomposite was fabricated by a facile and capping agent-free hydrothermal technique. The fabricated Ag doped CdS-WO2 nanocomposite were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and UV-vis diffuse reflectance (DRS) spectroscopy. The photocatalytic performance of synthesized photocatalysts was evaluated for the photodegradation of rhodamine B (Rh B) under visible light irradiation (VLI). The parameters used for the optimization of the photocatalyst were pH, catalyst dose, oxidant dose, and irradiation time. Based on this, a possible reaction mechanism for the enhancement of photocatalytic activity of Ag/CdS-WO2 has been proposed. Hence, we have a tendency to believe it might be a promising material that may be used for the photodegradation of organic pollutants present in wastewater.

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