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Article
Publication date: 17 May 2013

Abdullah M. Asiri, Khalid A. Alamry and Mahmoud A. Hussein

The purpose of this paper is to investigate the effect of annealing on photochromic performance of (E)‐dicyclopropylmethylene‐(2…

Abstract

Purpose

The purpose of this paper is to investigate the effect of annealing on photochromic performance of (E)‐dicyclopropylmethylene‐(2, 5‐dimethyl‐3‐furylethylid‐ene)‐succinicanhydride doped in polyacrylic acid thin film.

Design/methodology/approach

(E)‐dicyclopropylmethylene‐(2,5‐dimethyl‐3‐furyl‐ethylidene)‐succinic‐anhydride (DMDFS‐E) fulgide doped in polyacrylic acid thin films was prepared. DMDFS‐E fulgide doped in polyacrylic acid thin films was heated at various annealing temperatures. Photocoloration, photobleaching and photochemical fatigue resistance for the desired DMDFS‐E fulgide doped in polyacrylic acid thin films were studied.

Findings

Upon irradiation with UV light (366 nm), fulgide DMDFS‐E undergoes a conrotatory ring closure to the pinkish colored closed form C (523 nm). The later color was switched back to the original color when the films were irradiated with white light. The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product DMDFS‐C at its λmax of 523 nm. The first‐order plots of photocoloration reaction showed distinct linear line at different temperatures. The slope of these first‐order lines corresponding to the rate constants k. It was found that for photocoloration reaction, the rate constant of the photocoloration reaction was slower than the photobleaching reaction and both reactions decrease with increasing the annealing temperatures. It was found that there was almost improvement of photochemical fatigue resistance of fulgide DMDFS‐E doped in polyacrylic acid thin film at several of the annealing temperatures.

Originality/value

The results obtained in this work showed that the photochromic properties of DMDFS fulgide E were improved upon annealing the film at 100°C. Therefore, it would be recommended for improvement to apply fulgides as annealed polymer films.

Details

Pigment & Resin Technology, vol. 42 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 23 May 2008

A.A. Bahajaj and A.M. Asiri

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Abstract

Purpose

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Design/methodology/approach

The polystyrene films doped with photochromic fulgide were prepared and the effect of UV irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. The effect of heat was also determined.

Findings

A film of the green coloured fulgide 2‐E doped in polystyrene polymer was irradiated with UV light (366 nm), the film turned blue. The latter colour was partially switched back to the original green colour when the film was irradiated with a white light. Increasing the annealing temperatures, increases the percentage conversion of 2‐C to 2‐E. The observed large bathochromic shifts in λmax of 2‐C and the partial conversion of 2‐C to 2‐E were rationalised on the bases of electronic and steric effects. It was found that both isomers 2‐C and 2‐E absorbed white light and they interconvert. The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product 2‐C at its λmax of 620 nm. The apparent first‐order rate constants for both processes were determined. It was found that there was slight variation in the rate constant for photocoloration reaction with annealing temperature. On the other hand, the apparent first‐order rate constant of the photobleaching reaction decreases with increasing the annealing temperature.

Research limitations/implications

The polystyrene polymer doped photochromic fulgides described in the present paper was prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 37 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Abstract

Purpose

To evaluate the photochromic performance of fulgide 1E with ferrocene in polymer matrices.

Design/methodology/approach

The fulgide 1E with ferrocene dye 2 doped in polymethylmethacrylate was prepared and the effects of UV irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. The effect of heat was also determined.

Findings

A film of the brown coloured fulgide 1E with ferrocene doped in PMMA polymer was irradiated with ultraviolet light (365 nm), the film turned red. The later colour was partially switched back to the original brown colour when the film was irradiated with a white light. It was found that the rate constants of photocoloration reaction at initial stages are faster than those at late stages. Similarly, the photocoloration reaction was slower than the photobleaching reaction. Photocoloration reaction decreased with the increase of the annealing temperatures, but for photobleaching reaction, the rates were almost similar (at 46 and 82°C). The fatigue resistance of the film was greatly improved when the annealing temperature increased to 82°C.

Research limitations/implications

The polymethylmethacrylate polymer doped photochromic fulgide 1E and ferrocene 2 described in the present paper was prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 37 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 19 February 2018

Faisal K. Algethami, Hadi M. Marwani, Abdullah M. Asiri and Mohammed M. Rahman

The purpose of this study is to prepare various CeO2-based carbon material (CNT, CB, GO) nanocomposites through a wet chemical process for the development of a sensor…

Abstract

Purpose

The purpose of this study is to prepare various CeO2-based carbon material (CNT, CB, GO) nanocomposites through a wet chemical process for the development of a sensor probe to detect various environmental toxins by using an electrochemical approach under room temperature conditions. A comparative study on sensitive and selective phenolic sensor (4-methoxyphenol; 4-MP) has been fabricated by modifying a glassy carbon electrode (GCE) with various nanocomposites (NCs) such as CeO2, CeO2–CNT (carbon nanotubes), CeO2–CB (carbon black) and CeO2–GO (graphene oxide) NCs.

Design/methodology/approach

The CeO2–CNT NCs were prepared by the wet chemical method at low temperature. NCs were characterized by various methods such as transmission electron microscopy (TEM), Fourier-transform infra-red (FTIR), ultra-violet/visible (UV-Vis) spectroscopy and XRD (X-ray diffraction). CeO2–CNT NCs were immobilized as a film on the flat surface of the GCE by using binders (5% Nafion). The electrochemical measurements of the 4-MP detection with the CeO2–CNT NCs/Nafion/GCE sensor were studied by the current-voltage method.

Findings

In the optimal conditions, the sensitivity, detection limit and limit of quantification of 4-MP sensor probe were found to be 47.56 µAcm-2 µM−1, 12.0 ± 0.2 nM and 40.0 ± 0.5 nM (S/N of 3), respectively.

Research limitations/implications

This electrochemical sensor showed an acceptable analytical performance in the detection of 4-MP with higher sensitivity, lower detection limit, large dynamic concentration range, good reproducibility and fast response time.

Practical implications

This electrochemical approach can be applied practically for the determination of selective 4-MP in real environmental and extracted samples.

Social implications

CeO2–CNT NCs/Nafion/GCE sensor probe was used for the safety of environmental and health-care fields at larger scales.

Originality/value

This electrochemical approach is a significant achievement on the development of sensor probe. The results are indicated as being technically detailed with an up-to-date account of recent chemical sensor research studies.

Article
Publication date: 6 November 2009

A.A. Bahajaj, A.M. Asiri, A.M. Alsoliemy and A.G. Al‐Sehemi

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Abstract

Purpose

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Design/methodology/approach

The poly(methyl methacrylate) PMMA and epoxy resin doped with photochromic spirooxazine (SO) are prepared and the effects of ultraviolet (UV) irradiation are studied using spectrophotometer. The reversible reaction is effected using white light. Photochemical fatigue resistance of these films is also studied.

Findings

Irradiation of colourless 7′,8′‐dichloro‐1,3,3‐trimethylspiro[indoline‐2,3′‐[3H]benzo[b][1,4]oxazine] (SO) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction is photochemically induced by irradiation with white light. Photocolouration and photobleaching reactions follow a first‐order rate equation. It is found that photocoloration rate constant of (SO) in both matrices is almost the same, which is unexpected. On the other hand, the rate of photobleaching reaction of (PMC) in PMMA is twice slower than that in the epoxy resin. It seems that the presence of the two chlorine atoms at positions 7′ and 8′ of the benzooxazine moiety destabilise the PMC in epoxy resin film and results in speeding up the fading process compared to that in PMMA. SO doped in epoxy resin shows much better fatigue resistance than that doped in PMMA.

Research limitations/implications

The PMMA and epoxy resin polymers doped photochromic spirobenzooxazine described in this paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 38 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 21 March 2008

G.A. Baghaffar, A.M. Asiri, B.M. Babgi and M.S. Al‐Amoudi

To discuss synthesis and evaluation of organo‐metallic chalcones as second‐order nonlinear optical (SONLO) materials.

Abstract

Purpose

To discuss synthesis and evaluation of organo‐metallic chalcones as second‐order nonlinear optical (SONLO) materials.

Design/methodology/approach

The new chalcones have been synthesised via Knovoenagel reactions of ferrocen carboxaldehyde with two active methylene compounds.

Findings

The ferrocenyl chalcones prepared have shown bathochromic shift and thermal stability in polymeric film. On heating the dye films up to 80°C the extent of degradation reached up to 12 per cent and very small amount of degradation was observed at 43 and 60°C.

Originality/value

The paper shows that these compounds have UV‐Vis bathochromic shift, enabling them to be used as SONLO materials in the blue domain as well as dyes.

Details

Pigment & Resin Technology, vol. 37 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 23 March 2010

A.A. Bahajaj, A.M. Asiri, A.M. Alsoliemy and A.G. Al‐Sehemi

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Abstract

Purpose

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Design/methodology/approach

The poly(methyl methacrylate) (PMMA) and epoxy resin doped with photochromic spirobenzopyran were prepared and the effects of ultraviolet (UV) irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. Photochemical fatigue resistance of these films was also studied.

Findings

Irradiation of colourless 1′,3′,3′‐trimethyl‐6‐nitrospiro[2H‐1‐benzopyran‐2,2′‐indoline] spiropyran (SP) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction was photochemically induced by irradiation with white light. Photocolouration of SP doped in PMMA follows a first‐order rate equation (k=0.0011 s−1), while that doped in epoxy resin deviates from linearity. It was found that photobleaching follows a first‐order equation in both matrices. The photobleaching rate constant of PMC in both matrices is the same and equals 0.0043 s−1. Spirobenzopyran doped in PMMA shows better fatigue resistance than that doped in epoxy resin.

Research limitations/implications

The PMMA and epoxy resin polymers doped with photochromic spirobenzopyran described in the present paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 39 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 October 2005

A.A. Bahajaj and Abdullah M. Asiri

To evaluate the photochromic performance of photochromic compounds in polymer matrices.

Abstract

Purpose

To evaluate the photochromic performance of photochromic compounds in polymer matrices.

Design/methodology/approach

The epoxy resin doped with photochromic fulgide were prepared and the effect of UV irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. The effect of heat was also determined.

Findings

A film of fulgide 1‐E doped in epoxy polymer was irradiated with UV light (366 nm), the film turned pink. The later colour was switched back to the original colour when the film was irradiated with a white light. The photocoloration and photobleaching obeyed first order rate equations with rate constants being 4.19×10−3 s−1 and 2.86×10−2 s−1, respectively. It was found that the film showed a good fatigue resistance. Another film was preheated at 80°C for 1‐4 h. No change in the UV absorption spectra of the film was observed. Similarly, the photocoloration and photobleaching of the annealed film showed first order rate equations with rate constants being 8.77×10−3 s−1 and 4.02×10−2s−1, respectively. Interestingly, the photocoloration and photobleaching reactions of the annealed film were faster than those of the non‐annealed film.

Research limitations/implications

The epoxy resin doped photochromic fulgides described in the present paper was prepared and studied. The principle of study established can be applied to any type of resin or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 34 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 10 July 2007

A.M. Asiri, G.A. Baghaffar and N.H. Ismaiel

To discover new photochromic molecules suitable for various applications.

Abstract

Purpose

To discover new photochromic molecules suitable for various applications.

Design/methodology/approach

The synthesis of the new photochromic Aniline derivatives was accomplished by reaction of tetracyanoquinodimethane and anilines in polar solvents such as dimethylformamide.

Findings

A novel photochromic system had been designed and developed. The synthesis and photochromic properties of three aniline derivatives upon irradiation with ultraviolet light were studies in different solvents. The photochromic and thermochromic properties were affected markedly upon changing the solvent polarity. The new materials gave colourless to deep yellow coloration upon irradiation with ultraviolet, rendering them suitable candidates for optical storage media using the region of 700 nm.

Practical implications

A new photochromic system had been developed via a simple method. The new compounds showed photochromic, thermochromic, and solvatochromic properties making them potential candidates for many applications such as photo sensors, optical data storage, thermochromic sensors and heat sensitive materials.

Originality/value

The photochromic system was novel and hence the photochromic molecules were novel.

Details

Pigment & Resin Technology, vol. 36 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 September 2006

A.M. Asiri and M.S. Al‐Amoudi

To discuss synthesis and evaluation of organo‐metallic dyes as second‐order nonlinear optical (SONLO) material.

Abstract

Purpose

To discuss synthesis and evaluation of organo‐metallic dyes as second‐order nonlinear optical (SONLO) material.

Design/methodology/approach

New dyes have been synthesised via Knovoenagel reactions of ferrocene carboxyaldehyde and two active methylene compounds.

Findings

The ferrocenyl dyes prepared have shown bathochromic shift and thermal stability.

Practical implications

These compounds have UV‐Vis bathochromic shift, enabling them to be used as SONLO materials as well as dyes.

Originality/value

The paper provides further information on the thermal studies of these types of molecules.

Details

Pigment & Resin Technology, vol. 35 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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