scholarly journals New Grafted Copolymers Carrying Betaine Units Based on Gellan and N-Vinylimidazole as Precursors for Design of Drug Delivery Systems

Molecules ◽  
2020 ◽  
Vol 25 (22) ◽  
pp. 5451
Author(s):  
Stefania Racovita ◽  
Nicolae Baranov ◽  
Ana Maria Macsim ◽  
Catalina Lionte ◽  
Corina Cheptea ◽  
...  
Keyword(s):  
Graft Copolymerization ◽  
Polymer Concentration ◽  
Monomer Concentration ◽  
Ammonium Persulfate ◽  
Nitrogen Atmosphere ◽  
Sustained Drug Release ◽  
Reaction Conditions ◽  
Grafted Polymer ◽  
Grafted Copolymer ◽  
Grafting Reaction

New grafted copolymers possessing structural units of 1-vinyl-3-(1-carboxymethyl) imidazolium betaine were obtained by graft copolymerization of N-vinylimidazole onto gellan gum followed by the polymer-analogous reactions on grafted polymer with the highest grafting percentage using sodium chloroacetate as the betainization agent. The grafted copolymers were prepared using ammonium persulfate/N,N,N′,N′ tetramethylethylenediamine in a nitrogen atmosphere. The grafting reaction conditions were optimized by changing one of the following reaction parameters: initiator concentration, monomer concentration, polymer concentration, reaction time or temperature, while the other parameters remained constant. The highest grafting yield was obtained under the following reaction conditions: ci = 0.08 mol/L, cm = 0.8 mol/L, cp = 8 g/L, tr = 4 h and T = 50 °C. The kinetics of the graft copolymerization of N-vinylimidazole onto gellan was discussed and a suitable reaction mechanism was proposed. The evidence of the grafting reaction was confirmed through FTIR spectroscopy, X-ray diffraction, 1H-NMR spectroscopy and scanning electron microscopy. The grafted copolymer with betaine structure was obtained by a nucleophilic substitution reaction where the betainization agent was sodium chloroacetate. Preliminary results prove the ability of the grafted copolymers to bind amphoteric drugs (cefotaxime) and, therefore, the possibility of developing the new sustained drug release systems.

Preparation and Characterization of Homogeneous Grafted Cellulose in DMAc/LiCl System

2013 ◽  
Vol 312 ◽  
pp. 332-336 ◽  
Author(s):  
Fu Shan Chen ◽  
Zhong Hua Sun
Keyword(s):  
Reaction Time ◽  
Methyl Methacrylate ◽  
Graft Polymerization ◽  
Ammonium Persulfate ◽  
Mass Ratio ◽  
Reaction Conditions ◽  
Grafted Polymer ◽  
Grafting Reaction ◽  
The Media

The homogeneous grafting of methyl methacrylate (MMA) onto cellulose was carried out by using ammonium persulfate as an initiator. DMAc/LiCl was used as the solvent for the dissolution of cellulose and the media for the homogeneous graft polymerization of MMA onto cellulose. The efficient reaction conditions of the grafting reaction were confirmed by weighing methods. The results showed that the efficient reaction conditions were as follows: reaction time, 2h; mass ratio of MMA/cellulose, 1/1(g/g); mass ratio of initiator/cellulose, 6/50 (g/g); and reaction temperature, 80°C. Under these conditions, the GP of homogeneous grafted cellulose can reach 76%. The grafted polymer was characterized by FTIR, SEM and TG-DTA.

Study on the Synthesis and Properties of Water-Soluble Chitosan Grafted Copolymer

2011 ◽  
Vol 396-398 ◽  
pp. 1480-1485
Author(s):  
Shui Li Lai ◽  
Ning Yang ◽  
Qiang Chai
Keyword(s):  
Light Transmission ◽  
Ammonium Persulfate ◽  
Water Soluble ◽  
Raw Material ◽  
Reaction Conditions ◽  
Grafted Copolymer ◽  
Deacetylation Degree ◽  
Aqueous Solution Polymerization ◽  
Optimum Reaction ◽  
Polymerization Method

Grafted chitosan(CTS) copolymer was synthesized by the aqueous solution polymerization method, using the ammonium persulfate as initiator graft, Acrylamide（AM）and methacrylamide trimethyl Ammonium Chloride (DMC) as the grafted monomer. The effects of reaction conditions on grafted copolymerization were studied. When the deacetylation degree of chitosan as raw material is 86%, the optimum reaction to produce CTS -AM-DMC ternary graft copolymers by first AM and then DMC sequence were obtained at [initiator] 0.08%, 50°Cand 3.5h.The structure of CTS-AM-DMC was characterized by FTIR and XRD. When the dosage of synthetic product is 0.3mg/L, the effect of flocculation on the papermaking wastewater is obvious better, which can make the light transmission up to 99%, and CODCr to 9mg/L.

The Effects of the Reaction Conditions on the Grafting Degree of SiO2-g-PMAA Particle

2012 ◽  
Vol 581-582 ◽  
pp. 301-304
Author(s):  
Ke Hong Zhang ◽  
Hui Xiao ◽  
Jun Juan Du
Keyword(s):  
Silica Gel ◽  
Reaction Temperature ◽  
Methacrylic Acid ◽  
Graft Polymerization ◽  
Monomer Concentration ◽  
Reaction Conditions ◽  
Grafted Polymer ◽  
Limiting Value ◽  
Methacryloxypropyl Trimethoxysilane ◽  
Grafting Degree

Modified MPS-SiO2 particle was obtained by the bonding of 3-methacryloxypropyl trimethoxysilane (KH-570) on the surface of silica gel particle. The methacrylic acid (MMA) monomers were grafted on the surface of MPS-SiO2 particle to prepare the grafting particles SiO2-g-PMAA. The effects of reaction conditions on the graft degree were explored. The results indicate that the MMA monomers can be easily grafted on the surface of silica gel particle by using the method of graft polymerization. During the graft polymerization, the grafted polymer layer is a hindrance to the subsequent graft polymerization. Then the grafting degree of the polymer under a certain condition has a limiting value. The reaction conditions, such as monomer concentration, the amount of initiator, reaction temperature, have remarkably influence on the graft polymerization of SiO2-g-PMAA.

Graft Copolymerization of Soybean Protein Isolate and Methyl Methacrylate

2011 ◽  
Vol 695 ◽  
pp. 33-36
Author(s):  
Yan Lu ◽  
Xue Gang Luo ◽  
Xiao Yan Lin
Keyword(s):  
Methyl Methacrylate ◽  
Soy Protein ◽  
Graft Copolymerization ◽  
Soybean Protein ◽  
Ammonium Persulfate ◽  
Protein Isolate ◽  
Optimal Conditions ◽  
Reaction Conditions ◽  
Soybean Protein Isolate ◽  
Ft Ir

New thermoplastic soy protein isolated (SPI) and methyl methacrylate (MMA) copolymers (T-SPI) were prepared using graft copolymerization and initiated with ammonium persulfate (APS). The reaction conditions such as initiator concentration and temperature on the graft percentage (GP) were investigated. The single factor experimental showed that the optimal conditions of the graft reaction. The products were characterized by means of FT-IR and DSC. The results indicated that the monomer was grafted successfully on SPI and the T-SPI had a glass transition at 122°C, and the most important, the water absorption of materials declined obviously.

scholarly journals Modification of Track Etchedfluorinatea Films by Radiation Induced Graft Copolymerization

2009 ◽  
Vol 3 (2) ◽  
pp. 123-128
Author(s):  
Sunita Rattan ◽  
◽  
Inderjeet Kaur ◽  
Nitika Gupta ◽  
Devesh Kumar Avasthi ◽  
...  
Keyword(s):  
Total Dose ◽  
Graft Copolymerization ◽  
Monomer Concentration ◽  
Spectroscopic Techniques ◽  
Reaction Conditions ◽  
Force Microscopy ◽  
Atomic Force ◽  
Radiation Induced ◽  
Ftir Technique ◽  
Basic Characteristics

With the aim of improving the basic characteristics of Track Etched Membranes (TEMs), functionalization by graft copolymerization has been attempted in the present work. Thin films (25 μm) of poly(vinyl fluoride) (PVF) (Tedlar) were irradiated by swift heavy ions (110 MeV Si 8+ ). The irradiated films were chemically etched to form latent tracks. Atomic Force Microscopy (AFM) was used to ascertain the formation of latent tracks. Irradiation effects were studied using UV-visible spectroscopic techniques. The tracks were functionalized by gamma radiation induced grafting with 4-vinyl pyridine (4-VP). In order to anticipate the best grafting conditions, percentage of grafting was studied as a function of various reaction conditions such as (i) total dose, (ii) monomer concentration and (iii) amount of water. Maximum percentage of grafting (13.66 %) was obtained at a total dose of 57.024 kGy using 2 ml of 4-VP in 10 ml of water. The grafted films were characterized by FTIR technique

Graft Copolymerization of Soybean Protein Isolated and Methyl Acrylate as a New Thermoplastic Material

2011 ◽  
Vol 221 ◽  
pp. 644-648 ◽  
Author(s):  
Yan Lu ◽  
Xue Gang Luo ◽  
Xiao Yan Lin ◽  
Chi Zhang
Keyword(s):  
Soy Protein ◽  
Methyl Acrylate ◽  
Graft Copolymerization ◽  
Soybean Protein ◽  
Ammonium Persulfate ◽  
Optimal Conditions ◽  
Reaction Conditions ◽  
Thermoplastic Material ◽  
Ft Ir ◽  
Urea Aqueous Solution

New thermoplastic soy protein isolated (SPI) and methyl acrylate (MA) copolymers (T-SPI-g-MA) were prepared using graft copolymerization and initiated with ammonium persulfate (APS). The reaction conditions such as initiator concentration and temperature on the graft percentage (GP) were investigated. The single factor experimental showed that the optimal conditions for grafting of 15g SPI were: 4 g initiator of APS, 60 mL monomer of MA and in 250 mL 2M urea aqueous solution at 70 °C for 3 hours. The products were characterized by means of FT-IR and DSC. The results indicated that the monomer was grafted successfully on SPI and the T-SPI-g-MA had a glass transition at 22 °C.

DETERMINATION OF A SUITABLE CONDITION OF GRAFT COPOLYMERIZATION OF VINYLTRIETHOXYSILANE ONTO NR TO FORM NANOMATRIX STRUCTURE

2018 ◽  
Vol 91 (4) ◽  
pp. 767-775 ◽  
Author(s):  
Yuanbing Zhou ◽  
Yoshimasa Yamamoto ◽  
Seiichi Kawahara
Keyword(s):  
Silica Nanoparticles ◽  
Graft Copolymerization ◽  
Monomer Concentration ◽  
Minor Component ◽  
Suitable Condition ◽  
Average Diameter ◽  
Silica Matrix ◽  
Rubber Particles ◽  
Hydrolysis And Condensation ◽  
Nanomatrix Structure

ABSTRACT Graft copolymerization of vinyltriethoxysilane (VTES) onto NR particles in the latex stage is a unique reaction, since it occurs together with hydrolysis and condensation of the triethoxysilane group of VTES to form a colloidal silica linking to the rubber particles. These reactions may contribute to the formation of a silica nanomatrix structure that consists of a dispersoid of rubber particles as the major component and a silica matrix as the minor component. Here, the graft copolymerization of VTES followed by hydrolysis and condensation is investigated to determine a suitable condition to prepare NR with a silica nanomatrix structure. The mechanical properties of the resulting graft copolymer are discussed in relation to the morphology, silica content, and gel content of the rubber. Based on morphological observations, NR particles with an average diameter of approximately 1 μm are well dispersed in a nanomatrix consisting of silica nanoparticles. The thickness of the silica nanomatrix increases as the monomer concentration increases, and a long incubation time generates large silica nanoparticles. The tensile strength and viscoelastic properties are significantly improved by forming the silica nanomatrix structure, with its continuous structure that prevents the NR particles from merging.

Graft Copolymerization of Acrylamide onto Activated Starch Using Inverse Emulsion Polymerization

2011 ◽  
Vol 308-310 ◽  
pp. 600-605
Author(s):  
Dian Mo Zheng ◽  
Sheng Gan Zhu ◽  
Li Ping Wu
Keyword(s):  
Ball Milling ◽  
Graft Copolymerization ◽  
Chemical Reactivity ◽  
Weight Ratio ◽  
Monomer Conversion ◽  
Ammonium Persulfate ◽  
Grafting Efficiency ◽  
Inverse Emulsion ◽  
Initiation System ◽  
Ft Ir

Activated starch was prepared by ball milling before used. Graft copolymerization of acrylamide onto activated starch was carried out in inverse emulsion using a redox initiation system of ammonium persulfate and sodium bisulfite. The effects of ball-milling time, reaction temperature, initiator concentration and weight ratio of acrylamide to starch on the conversion of monomer, grafting percentage and grafting efficiency were studied. The structure and properties of the graft copolymer and activated starch were characterized by FT-IR, XRD and SEM. The results showed that ball milling could progressively destroy the crystalline structure of starch and improve the chemical reactivity. The monomer conversion, grafting percentage and grafting efficiency of grate copolymerization were 96.6%、62.4%、85.49%, respectively.

scholarly journals Determination of Nickel in End-Fitting of Spoolable Reinforced Plastic Line Pipe

2018 ◽  
Vol 142 ◽  
pp. 01002
Author(s):  
Xiaodong Shao
Keyword(s):  
Ammonium Persulfate ◽  
Reaction Conditions ◽  
Line Pipe ◽  
Acid Gas ◽  
Determination Of Nickel ◽  
Reinforced Plastic ◽  
Relative Standard ◽  
Optimum Reaction ◽  
Fitting In

Spoolable reinforced plastic line pipe will be widely used in the exploitation of acid gas and oil wells. End-fitting is a mechanical device that forms the transition from the spoolable reinforced plastic line pipe to the connector. It was well known that nickel was an important element in the end-fitting. In this paper, a novel spectrophotometric method was described for determination of nickel in the end-fitting of spoolable reinforced plastic line pipe. The method was based on the color reaction between nickel and dimethylglyoxime, which was favored in an alkaline medium, producing a red compound in the presence of ammonium persulfate as an oxidant. Under the optimum reaction conditions the absorption value was proportional to the concentration of nickel in the range of 0.080~0.50% (R2 = 0.9999), and the relative standard deviation was less than 3.0% (n=5). The proposed method was applied successfully to determine nickel in end-fitting of spoolable reinforced plastic line pipe.

Orthogonal Test Design for Optimization of Dispersive Type Cement Slurry Fluid Loss Control Additive Used in Petroleum Drilling

2011 ◽  
Vol 361-363 ◽  
pp. 487-492
Author(s):  
Sheng Lai Guo ◽  
Yu Huan Bu
Keyword(s):  
Ph Value ◽  
Orthogonal Experiment ◽  
Monomer Concentration ◽  
Ammonium Persulfate ◽  
Fluid Loss ◽  
Oil Well ◽  
Cement Slurry ◽  
Orthogonal Test Design ◽  
Total Monomer Concentration ◽  
Loss Control

The fluid loss control additive plays a key role in reducing reservoir damage and improving the cementing quality of an oil well. Aiming at good fluid loss control ability and excellent dispersibility, a new dispersive type fluid loss control additive was synthesized through orthogonal experiment with 2-acrylamido-2- methyl propane sulfonic acid, acrylamide, N, N-dimethylacrylamide and maleic anhydride. The orthogonal experiment result shows that the influence on the properties of FLCA decreases in the order: PH value > monomer concentration > monomer mole ratio > initiator concentration > temperature. The result indicates that the optimal conditions for FLCA were 4/2.5/2.5/1 of mole ratio of AMPS/AM /NNDMA/MA, 32.5% total monomer concentration in deionized water, 1.0% (by weight of monomer) ammonium persulfate/sodium bisulfite, 4 of PH value, 40°Cof temperature. The synthesized copolymer was identified by FTIR analysis. The results show the dispersive type fluid loss control additive has excellent dispersibility, fluid loss control ability, thermal resistant and salt tolerant ability. As the temperature increases, the thickening time of the slurry containing the synthesized additive reduces. The copolymer is expected to be a good fluid loss control additive.

Sign in / Sign up

Export Citation Format

Share Document