Percentage Of Grafting Efficiency Research Articles

Grafting of O-Carboxymethyl Chitosan with Acrylonitrile and Studying some of its Properties and Applications

Preparation of o-carboxymethyl Chitosan was done, wich is important derivative of chitosan. Grafting copolymerization of acrylonitrile onto o-carboxymethyl chitosan was accomplished using ammonium cerium sulfate (CAS) as an initiator. Resulting graft of o-carboxymethyl chitosan was characterized by FT-IR spectrum and DTA analysis to be compared with o-carboxymethyl chitosan. Properties such as water swelling and solubility were studied for each, whereas,. Percentage of grafting efficiency (GE%) and yield of grafting (GY%) were determined. The efficiency of grafted ocarboxymethyl chitosan (CMCh-g-PAN) to remove dyes(direct black dyes, dispersed red dyes) from industrial waste water was also determined. The results reveal good efficient absorption of black dyes more than red dyes. Efficiency from different concentrations of grafted o-carboxymethyl chitosan(CMCh-g-PAN) to reveal percentages of elimination ions from their solutions metallic ions Cu2+,Pb2+,Cd2+and Sn2+ from their solutions at room temperature with mechanical stirring for 24 hrs were also determined .It has been shown that grafted o-carboxymethyl chitosan has important role in elimination of lead ion comparing with other ions, As a result, elimination percentages of ions increase as follow: Cd2+< Sn2+< Cu2+<. Pb2+

Synthesis of Gum Arabic-g-polyaniline using diode laser

Grafting of polyaniline (PANI) on Gum Arabic (GA) was carried out in the presence of ceric ammonium nitrate (CAN) under acidic conditions by diode laser as initiator. The grafting condition was optimized by varying the diode laser power, exposure time, concentrations of PANI, CAN, GA, reaction time and temperature were carefully optimized to achieve the highest percentage of grafting yield % GY (90%) and percentage of graft efficiency % GE (36%). The Fourier-transform infrared spectroscopy (FTIR), 1H NMR, X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA), and Scanning electron micrographs (SEM) techniques have been used for the characterization of the produced graft copolymer GA-g-PANI, which used as drug delivery carrier to control cancer in brain. This study focused to new trends and latest developments in this area where diode laser was found to be efficient and, clean method for synthesis GA-g-PANI.

DIODE LASER-INDUCED GUM ARABIC-G-ACRYLIC ACID

Aim of this study is to synthesis Gum Arabic-g- Acrylic acid using laser light as initiator to synthesis clean product that is free from any trace's chemicals substances. Firstly the graft of acrylic acid on Gum Arabic, initiated by (C.A.N), will be study under a nitrogen gas to get reaction conditions such as graft copolymerization temperature, reaction time, and Gum Arabic, monomer, and initiator concentrations. Percentage of graft efficiency (% GE) and percentage of graft yield (% GY) will be collocated. Graft copolymer will be recognized using FTIR Spectroscopy, (TGA) analysis, (XRD) diffraction and (SEM) microscope. The graft will be later used in drug delivery carrier to control cancer in brain and matrices for colon aiming medicine delivery systems. This study focused to new trends and latest developments in this area where laser light was found to be efficient and clean method for synthesis GA-g-Acrylic Acid.

Synthesis and characterization of acrylic acid grafted gum tragacanth and its effect in Fe2+ removal

In this paper, grafting of acrylic acid monomer on Gum tragacanth was performed. Variable of experiment included concentration of initiators and monomer, time, and temperature. Grafting efficiency was measured in the term of percentage of grafting (%G) and percentage of grafting efficiency (%E). Effectiveness of grafted gum in ferrous ion removal at different condition was assessed. According to this study, grafting was influenced by different concentration of initiators. The best result obtained at 5 × 10-3 mol/dm-3 [Fe2+], 1.35 × 10-3 mol/dm3 [H+], 4 × 10-3 mol/dm3 potassium monopersulfate and monomer concentration = 5 × 10-2 mol/dm3. Amount of added gum was restricted to 0.25 g, addition of more gum resulted to abrupt decrease of both parameters. Time and temperature affected grafting reaction and the best condition for grafting was 25 oC, 90 min. Finally, the ability of resultant grafted gum for removal of ferrous ion from aqueous media was assessed. The maximum removal of ferrous ion took place at pH = 6, grafted gum = 150 mg and contact time 60 min.

Synthesis of Cassava Waste Pulp-Acrylamide Super Absorbent: Effect of Initiator and Cross-Linker Concentration

Cassava waste pulp (CWP) contains high carbohydrates that can be modified into super absorbent polymer (SAP) through grafting and cross-linking copolymerization. Acrylamide (AM) was grafted onto CWP with ammonium persulfate (APS) as the initiator and N,N'-methylene-bis-acrylamide (MBA) as the cross-linker under atmospheric nitrogen. The effect of APS and MBA concentrations on water absorption capacity of saponified SAP was studied, while the evaluation of grafting ratio (GR) and grafting efficiency (GRE) was conducted on unsaponified SAP. The grafting success was indicated by the occurrence of IR peaks at wave numbers of 573, 765, 858, and 1667 cm-1. In the saponified SAP, the very intense characteristic band at 1562 cm-1 is due to C=O asymmetric stretching in the carboxylate anion. Saponification increases significantly water absorption capacity compared to that of unsaponified SAP (from 39.79 g/g to 578.23 g/g). The highest water absorption capacity is reached at 0.74% APS and 0.09% MBA. The percentage of GRE and GR tends to increase with increasing APS concentration until reaching the highest value and then decreases. Effect of MBA concentration on water absorption capacity, GR, and on GRE is similar to the effect of initiator concentration on GR and GRE.

Ce(IV) ion initiated graft polymerization of glycidylmethacrylate onto a demineralized bone matrix: effect of reaction parameters

Studies on chemical modification of demineralized bone matrix (DBM) have opened new arenas in the field of clinical orthopedics owing to its potential osteoinductivity with desired chemical functionality. To widen its usage to biomolecular delivery, graft polymerization of glycidylmethacrylate onto DBM was carried out by a free-radical initiating process using ceric ammonium nitrate as an initiator. The evidence of the grafting reaction was examined by chemical analysis using Fourier transform IR spectroscopy. The grafting condition was standardized by regulating the reaction parameters such as the concentrations of the backbone, the monomer and the initiator, the polymerization temperature and time. The optimum polymerization temperature and time to have the maximum grafting yield were 40 °C and 3 h, respectively. The percentage of grafting and the percentage of grafting efficiency were determined as a function of the reaction parameters, and both were found to increasing initially and thereafter decrease in most of the cases. The grafting results are discussed in a detailed fashion and a reaction mechanism is proposed.

Photograft copolymerization of methyl methacrylate on silk fiber using titanium(III) chloride-potassium persulphate redox initiator in a limited aqueous system. I

Graft copolymerization of methyl methacrylate (MMA) onto mulberry silk fibers has been investigated in a limited aqueous system employing titanium(III) chloride-K 2 S 2 O 8 as the redox initiator under a photoactive condition with visible light. Polymerization in the presence of light at 32 ± 1°C has been found to be more pronounced than in the dark under identical conditions. The percentage of grafting, the percentage of total conversion, and the percentage of grafting efficiency have been studied by varying the reaction time, concentration of monomer, initiator concentration, solvent composition, and pH of the medium. A high percentage of grafting (∼ 93%), high grafting efficiency (∼ 97%), and the percentage of total conversion (∼ 25%) have been obtained with little homopolymer formation. Characterization of the grafted fibers has been investigated by Fourier transform infrared spectroscopy and scanning electron microscopy. Finally, the reaction mechanism has been discussed by considering hydrogen bonding.

Graft Copolymerization of Poly(methyl Methacrylate) onto Wool by the Potassium Persulfate-Thiomalic Acid Redox Couple in the Presence of Atmospheric Oxygen. Part I

Abstract The graft copolymerization of poly (methyl methacrylate) [PMMA] onto wool initiated by the potassium persulfate-thiomalic acid (TMA) redox couple has been investigated in the presence of atmospheric oxygen. The percentage of grafting efficiency and polymerization as a function of initiator, activator, monomer, temperature, time, and wool was estimated. Evidence of grafting was confirmed by IR spectroscopy. It was observed that the grafting ranged from 25 to 70% depending upon the concentration of the redox system, the time, and the temperature.