Gum colocasia-g-polyacrylamide: Microwave-assisted synthesis and characterization

In the present investigation, an attempt has been made for grafting of acrylamide on the backbone of Colocasia esculenta by using microwave-assisted grafting method, which is a convenient and versatile route for the development of polysaccharide-based materials. The dried mucilage of colocasia was prepared from fresh rhizomes. The optimization was performed by using Box Behnken matrix design (BBD) and response surface methodology (RSM) using design expert software. A series of graft polymers, varying in the amount of acrylamide, ammonium persulphate and microwave irradiation was prepared. The effect of Microwave time, gum concentration and power on percentage yield, percentage grafting and percentage grafting efficiency has been optimized and evaluated by 3D surface response graphs. It has been observed that power and irradiation time has a significant synergistic effect on % yield, % grafting and % grafting efficiency however gum concentration produce slight increment up to a limit after that the effect becomes almost constant. The selected optimized formulation is F8 with a percentage yield of 99.57%, percentage grafting of 634.33% and percentage grafting efficiency of 87.49%. Optimized formulation was subjected to Fourier transform infrared spectroscopy, Differential scanning calorimetry, X-ray diffraction and Scanning electron microscopy for characterization which committed the grafting of acrylamide on Colocasia esculenta.

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GUM KARAYA-G-POLY (ACRYLAMIDE): MICROWAVE ASSISTED SYNTHESIS, OPTIMISATION AND CHARACTERISATION

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2020v12i5.37732 ◽

2020 ◽

pp. 143-152

Author(s):

LOVELEENPREET KAUR ◽

G. D. GUPTA

Keyword(s):

Ammonium Nitrate ◽

Irradiation Time ◽

Ceric Ammonium Nitrate ◽

Microwave Assisted Synthesis ◽

Scanning Calorimetry ◽

Box Behnken Design ◽

Grafting Efficiency ◽

Microwave Assisted ◽

Gum Karaya ◽

Karaya Gum

Objective: The objective of the present research is to formulate acrylamide grafted Karaya gum by using microwave-assisted grafting method and optimisation is performed by using Box behnken design. Methods: The extracted mucilage of gum Karaya was modified into grafted gum Karaya by using a microwave-assisted method. Acrylamide was used as monomer and ceric ammonium nitrate (CAN) is used as redox initiator. The experimental design for optimisation include three independent variables gum concentration (X1), ceric ammonium nitrate (CAN) amount (X2) and irradiation time (X3) while the dependent variables were % yield (Y1), % grafting (Y2) and % grafting efficiency (Y3). The optimised formulation was characterized by fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), x-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. Results: After optimisation the formulation with acrylamide amount 5 g, ceric ammonium nitrate amount 200 mg and irradiation time of 2 min was selected as optimized formulation. The optimised formulation has percentage grafting of 853.5%, with grafting efficiency of 77.59%. Conclusion: The application of box behnken design for optimisation was performed successfully in microwave assisted grafting of acrylamide on karaya gum.

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Surfactant-Free Microwave-Assisted Synthesis of Fe-Doped ZnO Nanostars as Photocatalyst for Degradation of Tropaeolin O in Water under Visible Light

Journal of Nanomaterials ◽

10.1155/2015/190747 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Tsz-Lung Kwong ◽

Ka-Fu Yung

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Irradiation Time ◽

Catalyst Loading ◽

Orthogonal Experimental Design ◽

Microwave Assisted Synthesis ◽

X Ray ◽

Microwave Assisted ◽

Vis Spectroscopy ◽

Doped Zno

Iron-doped zinc oxide nanostar was synthesized by the microwave-assisted surfactant-free hydrolysis method. The as-synthesized Fe-doped ZnO nanostars catalyst was fully characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), and diffuse reflectance UV-vis spectroscopy (UV-DRA). The photocatalytic activity of the photocatalyst was investigated for the photocatalytic degradation of Tropaeolin O under visible light irradiation. It is observed that the doping of Fe ions enhances the absorption of the visible light and thus the photocatalytic degradation rate of Tropaeolin O would increase. Despite the Taguchi orthogonal experimental design method, the photocatalytic conversion could be achieved at 99.8% in the Fe-doped ZnO catalyzed photodegradation reaction under the optimal reaction conditions of catalyst loading (30 mg), temperature (60°C), light distance (0 cm), initial pH (pH = 9), and irradiation time (3 h). The Fe-doped ZnO photocatalyst can also be easily recovered and directly reused for eight cycles with over 70% conversion.

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Microwave-assisted ring-opening polymerization of poly (glycolic acid-co-lactic acid) copolymers

e-Polymers ◽

10.1515/epoly.2010.10.1.557 ◽

2010 ◽

Vol 10 (1) ◽

Cited By ~ 3

Author(s):

Guang Li ◽

Na Zhao ◽

Wei Bai ◽

Dong Liang Chen ◽

Cheng Dong Xiong

Keyword(s):

Lactic Acid ◽

Ring Opening ◽

Glycolic Acid ◽

Raw Materials ◽

Irradiation Time ◽

Ring Opening Polymerization ◽

Feed Ratio ◽

Microwave Assisted Synthesis ◽

Component Ratio ◽

Microwave Assisted

AbstractThe microwave-assisted synthesis of poly(glycolic acid-co-lactic acid) (PGLA) copolymers by ring-opening polymerization of glycolide (GA) and L-lactide (L-LA) was studied. The microwave irradiation time and feed ratios on the molecular weights, as well as the thermal properties of the copolymers were discussed. These copolymers were characterized by 1H-NMR, GPC and DSC. It was found that the largest molecular weight ([η]: 0.8745 dL/g) of PGLA5050 was obtained at the irradiation time of 5 min. The color of the copolymers changed from white to light brown, and the yield was higher with the extension of the irradiation time. The molar component ratio of GA in PGLA (FG) was higher than the initial GA feed ratio (nGA) in the raw materials. As the nGA content increased, the glass transition temperature (Tg) of the copolymers decreased and the melting temperature (Tm) of the copolymers increased.

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Photocatalytic Activity of Mixed Phase TiO2 from Microwave-Assisted Synthesis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.664.661 ◽

2013 ◽

Vol 664 ◽

pp. 661-666 ◽

Cited By ~ 1

Author(s):

Nuchanaporn Pijarn ◽

Sirithan Jeimsirilers ◽

Supatra Jinawath

Keyword(s):

Methylene Blue ◽

Titanium Dioxide ◽

Photocatalytic Activity ◽

Organic Compounds ◽

Irradiation Time ◽

Synthesis Method ◽

Microwave Assisted Synthesis ◽

Microwave Assisted ◽

Bacteria And Fungi ◽

Hydrolysis Of

Photocatalyst is an environmental clean-up material when exposed to light. It can decompose organic compounds, bacteria and fungi as well as foul odors. Titanium dioxide (TiO2) has long been well known for its powerful photocatalytic activity. However, its properties depend on several factors and synthesis method is one of them. In this work, TiO2powders were prepared by three methods, namely microwave-assisted hydrolysis of titanium oxysulfate (TiOSO4), hydrolysis of TiOSO4, and also by calcining of TiOSO4. Photocatalytic activity of the obtained TiO2powders were evaluated through the decomposition of methylene blue in comparison with P25 (Degussa). Results showed that the TiO2prepared at conditions of microwave 100 watts, irradiation time of 10 min was most effective when compared with the others in this work.

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Phase Transformation of VO2Nanoparticles Assisted by Microwave Heating

The Scientific World JOURNAL ◽

10.1155/2014/841418 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Phatcharee Phoempoon ◽

Lek. Sikong

Keyword(s):

Microwave Power ◽

Irradiation Time ◽

Power Level ◽

Thermal Analyses ◽

Morphological Properties ◽

Microwave Assisted Synthesis ◽

Tem Analysis ◽

Microwave Assisted ◽

Thermochromic Properties ◽

Microwave Power Level

The microwave assisted synthesis nowadays attracts a great deal of attention. Monoclinic phase VO2(M) was prepared from NH4VO3andH2C2O4·2H2Oby a rapid microwave assisted technique. The synthesis parameters, microwave irradiation time, microwave power, and calcinations temperature were systematically varied and their influences on the structure and morphology were evaluated. The microwave power level has been carried out in range 180–600 W. TEM analysis demonstrated nanosized samples. The structural and morphological properties were measured using XRD, TEM, and thermal analyses. The variations of vanadium phase led to thermochromic properties.

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Microwave Assisted Synthesis and Optical Properties of Highly Fluorescent N-Doped Carbon Dots

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.22334 ◽

2019 ◽

Vol 31 (12) ◽

pp. 2897-2902

Author(s):

D. Koteswararao ◽

B. Rajkumar ◽

K. Prameela ◽

K. Ashok ◽

G. Sridevi

Keyword(s):

Optical Properties ◽

Carbon Dots ◽

Irradiation Time ◽

Guanidine Hydrochloride ◽

Fluorescence Emission ◽

Microwave Assisted Synthesis ◽

Solid State Method ◽

Microwave Assisted ◽

Wide Range ◽

Doped Carbon Dots

Herein, a rapid microwave assisted solid state method is reported for the synthesis of highly fluorescent N-doped carbon dots (NCDs) using citric acid as carbon source and guanidine hydrochloride as N-dopant. Synthetic parameters such as microwave power, irradiation time and reactants ratio were optimized to produce high quality N-doped carbon dots. The N-doped carbon dots were well characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), SEM-EDS, FTIR, UV-visible and fluorescence spectroscopies. N-Doped carbon dots exhibited bright emission with a quantum yield of 11 %. Detailed study of their optical properties revealed their excellent property of resistance to photo bleaching, high ionic strength and solution pH. Further they exhibited excitation dependent emission behaviour, high aqueous solubility and a long shelf life of 60 days. This strong fluorescence emission combined with high stability make N-doped carbon dots a promising fluorescent probe for wide range of applications.

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Green Microwave-assisted Synthesis of ZnO-Ag Nanocomposite using Clove Oil (Syzygium aromaticum L.) and Its Bioactivity against Staphylococcus aureus

The Journal of Pure and Applied Chemistry Research ◽

10.21776/ub.jpacr.2020.009.02.513 ◽

2020 ◽

Vol 9 (2) ◽

pp. 82-90

Author(s):

Elvina Dhiaul Iftitah ◽

◽

Rizki Wahyu Aji Wibowo ◽

Masruroh Masruroh ◽

Khoirun Nisyak ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Size Range ◽

Irradiation Time ◽

Inhibition Zone ◽

Xrd Analysis ◽

Microwave Assisted Synthesis ◽

Syzygium Aromaticum ◽

Microwave Assisted ◽

Product Characterization ◽

Ft Ir

Microwave-assisted synthesis of zinc oxide-silver (ZnO-Ag) nanocomposite using clove (Syzygium aromaticum L.) oil has been investigated. Variation of solvents and irradiation time of microwave was studied. The product characterization was carried out using XRD, FT-IR, and SEM-EDS. The XRD analysis indicates ZnO-Ag nanocomposite has a polycrystalline structure. The ZnO peak was detected at 2θ = 31.99; 34.58 and 68.05, whereas the Ag peak was detected at 2θ = 38.36 and 44.49. The increasing of irradiation time reduces the crystallite size, and generally has size range between 9 and 12 nm. SEM-EDS confirmed the existence of the ZnO-Ag nanocomposite with percentage of Zn (46.89%), O (29.72%) and Ag (23.39%). Moreover, antibacterial evaluation on Staphylococcus aureus give the inhibition zone in 13.3 mm. This result slightly gives better activity than the reference.

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Microwave-assisted synthesis of the lipase-catalyzed ring-opening copolymerization of ε-caprolactone and ω-pentadecanolactone: Thermal and FTIR characterization

e-Polymers ◽

10.1515/epoly-2020-0067 ◽

2020 ◽

Vol 20 (1) ◽

pp. 651-658

Author(s):

Wilberth A. Herrera-Kao ◽

Manuel J. Aguilar-Vega ◽

José Manuel Cervantes-Uc

Keyword(s):

Ring Opening ◽

Microwave Assisted Synthesis ◽

Scanning Calorimetry ◽

Absorption Bands ◽

Intense Band ◽

Microwave Assisted ◽

Degradation Temperature ◽

Ftir Characterization ◽

Methylene Groups ◽

Thermal Stability Of

AbstractMicrowave-assisted synthesis of the lipase-catalyzed ring opening polymerization of ε-caprolactone (ε-CL) and ω-pentadecanolactone (ω-PDL) monomers was studied. A series of P(CL-co-PDL), with different molar feed ratios, including (ε-CL/ω-PDL) 100/0, 75/25, 50/50, 25/75, and 0/100, were synthesized. The resulting polyesters were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The microwave-assisted polymerization of the monomers reached high conversions (91–95%) within 60 min. FTIR spectra showed the typical absorption bands of these polyesters. A very intense band in the carbonyl region, which was shifted from 1,720 cm−1 for PCL to 1,732 cm−1 for PPDL homopolymer, as well as peaks owing to methylene groups in the 2,990–2,850 cm−1 range. DSC results revealed that all polyester samples were semi-crystalline. Interestingly, the copolymers exhibited only one melting peak (Tm), and their Tm values linearly increased from 57°C to 95°C as PPDL concentration was increased. Thermal stability of polyesters also depended on PDL content; an increase in PDL concentration increases polymer degradation temperature (Td).

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MASTIC-G-POLY (ACRYLAMIDE): MICROWAVE-ASSISTED SYNTHESIS AND CHARACTERISATION

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2021v13i2.40551 ◽

2021 ◽

pp. 228-234

Author(s):

MOHIT KUMAR ◽

SURAJPAL

Keyword(s):

Design Space ◽

Maximum Yield ◽

Ceric Ammonium Nitrate ◽

Microwave Assisted Synthesis ◽

Box Behnken Design ◽

Critical Quality Attributes ◽

Grafting Efficiency ◽

Microwave Assisted ◽

Free Radical Initiator ◽

Poly Acrylamide

Objective: The objective of the present investigation was the synthesis of grafted co-polymer gum mastic using acrylamide as the monomer. Methods: 3-factor 3-level response surface Box-Behnken design, which requires 15 runs including three replicates of the central run, was used for the synthesis of graft copolymers of mastic gum with acrylamide using ceric ammonium nitrate as the free radical initiator. The critical synthesis and process parameters; CSPP (A = concentration of monomer, B = concentration of initiator and C= Temperature) to generate design space and optimize formulation with an aim to obtain critical quality attributes (CQA, Y1 =% Yield, Y2 =% Grafting, Y3 =% grafting efficiency). Result: Formulation F14 having a maximum % yield of 75.89% with % grafting of 210% and % grafting efficiency 51.57% was selected as best. Conclusion: The microwave-assisted grafted mastic gum was prepared successfully and optimized by using Box Behnken design.

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Microwave Assisted Synthesis of ZnO Nanoparticles: Effect of Precursor Reagents, Temperature, Irradiation Time, and Additives on Nano-ZnO Morphology Development

Journal of Materials ◽

10.1155/2013/478681 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 38

Author(s):

Gastón P. Barreto ◽

Graciela Morales ◽

Ma. Luisa López Quintanilla

Keyword(s):

Irradiation Time ◽

Radiation Power ◽

Microwave Assisted Synthesis ◽

X Ray Diffraction ◽

Nano Zno ◽

X Ray ◽

Microwave Assisted ◽

Vis Spectroscopy ◽

Temperature Irradiation

The effect of different variables (precursor reagents, temperature, irradiation time, microwave radiation power, and additives addition) on the final morphology of nano-ZnO obtained through the microwave assisted technique has been investigated. The characterization of the samples has been carried out by field emission scanning electron microscopy (FE-SEM) in transmission mode, infrared (FTIR), UV-Vis spectroscopy, and powder X-ray diffraction (XRD). The results showed that all the above-mentioned variables influenced to some extent the shape and/or size of the synthetized nanoparticles. In particular, the addition of an anionic surfactant (sodium di-2-ethylhexyl-sulfosuccinate (AOT)) to the reaction mixture allowed the synthesis of smaller hexagonal prismatic particles (100 nm), which show a significant increase in UV absorption.

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