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.

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 PMAA/SiO2 Composite Particle Via Emulsion Polymerization

2012 ◽  
Vol 528 ◽  
pp. 184-187 ◽  
Author(s):  
Ke Hong Zhang ◽  
Jun Juan Du ◽  
Hui Xiao ◽  
Yan Yuan
Keyword(s):  
Acrylic Acid ◽  
Emulsion Polymerization ◽  
Silica Gel ◽  
Graft Polymerization ◽  
Polymer Layer ◽  
Grafted Polymer ◽  
Chemically Modified ◽  
Ft Ir ◽  
Silica Gel Particles

Silica gel particle was chemically modified by using 3-methacryloxypropyl trimethoxysilane (KH-570) as coupling agent. Then poly methyl acrylic acid (PMAA) was grafted on the surface of particles MPS-SiO2 with the method of Emulsion Polymerization, and grafting particles PMMA/SiO2 were prepared. The grafting particle PMAA/SiO2 was characterized by using FT-IR, TG and SEM. The experimental results show that the graft polymerization of methyl acrylic acid (MAA) on onto the surface of silica gel particles can successfully realized using the method of “graft from”. During the graft polymerization, the grafted polymer layer is a hindrance to the subsequent graft polymerization. When the grafted polymer layer reach to a certain density via overlapping and entwisting, a kinetic barrier will be built up. Hence, the grafting degree of the polymer under a certain condition has a limiting value.

Synthesis of Konjac Glucomannan-Graft-Methacrylic Acid Copolymer

2012 ◽  
Vol 554-556 ◽  
pp. 307-310
Author(s):  
Hui Min Han ◽  
Chi Zhang ◽  
Jing Xu ◽  
Peng Qu ◽  
Ye Zhou ◽  
...  
Keyword(s):  
Free Radical ◽  
Reaction Temperature ◽  
Methacrylic Acid ◽  
Konjac Glucomannan ◽  
Initiator Concentration ◽  
Reaction Conditions ◽  
Radical Initiation ◽  
Acid Copolymer ◽  
Free Radical Initiation ◽  
Methacrylic Acid Copolymers

Konjac glucomannan is a kind of natural polysaccharides with excellent biocompatibility and biodegradable activities. In this paper, a series of Konjac glucomannan-graft-methacrylic acid copolymers were prepared by the free-radical initiation grafting Konjac Glucomannan (KGM) with methacrylic acid(MA). The reaction conditions such as reaction temperature, KGM and MA ratio and initiator concentration, were investigated, and chemistry of KGM and its MA grafted copolymers were characterized using FTIR.

Research of Immobilization of Transglutaminase on Polypropylene Microporous Membranes

2011 ◽  
Vol 341-342 ◽  
pp. 338-344 ◽  
Author(s):  
Zhi Guo Na ◽  
Xue Fei Wang ◽  
Yong Qiang Ma ◽  
Lei Qian ◽  
Hong Yu Yan
Keyword(s):  
Ferrous Sulfate ◽  
Monomer Concentration ◽  
Cross Linking ◽  
Sulfate Concentration ◽  
Microporous Membranes ◽  
Activation Time ◽  
Reaction Conditions ◽  
Ammonium Ferrous Sulfate ◽  
Optimal Reaction ◽  
Grafting Degree

Activated ozone as the carrier，crylic acid as the monomer and glutaraldehyde as the cross-linking agent were used to research the immobilization of transglutaminase on polypropylene microporous membranes. The effect of ozone activation time，grafting time，grafting temperature，monomer concentration and ammonium ferrous sulfate concentration on grafting degree were studied, the Immobilization conditions were also studied. We found the optimal reaction conditions as following: consistency of hexamethylendiamine was 15%，at 50°C for 120min and consistency，at 30°C for 45minites，consistency of enzyme was 15mg/mL at 4°C. So the immobilized amount of protein could come to 30.23mg/g membrane and the activity of immobilized MTG come to 16.9U/g membrane.

scholarly journals Polyurethane modification with acrylic acid by Ce(IV)-initiated graft polymerization

2016 ◽  
Vol 14 (1) ◽  
pp. 206-214 ◽  
Author(s):  
Beata A. Butruk-Raszeja ◽  
Paulina A. Trzaskowska ◽  
Aleksandra Kuźminska ◽  
Tomasz Ciach
Keyword(s):  
Acrylic Acid ◽  
Graft Polymerization ◽  
Monomer Concentration ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Carboxyl Groups ◽  
Hydroxyl Groups ◽  
Reaction Conditions ◽  
Measurement Analysis ◽  
Surface Hydroxylation

AbstractThis paper presents a method for polyurethane surface functionalization for tissue engineering applications. Functionalization has been carried out by grafting acrylic acid to the polyurethane surface with the use of radical polymerization with a Ce4+ initiator. Contrary to other papers suggesting that the presence of hydroxyl groups are essential for successful grafting via ceric ions, we propose a method with the omission of the surface hydroxylation step. The influence of reaction conditions: reaction time, reaction temperature and monomer concentration on carboxyl groups surface density has been analyzed and described. The quantity of carboxyl groups on the surface was determined with the use of the TBO method. Materials grafted with acrylic acid have been subjected to conjugation with a peptide using sulfoNHS/ EDC chemistry. Successful incorporation of the peptide has been confirmed by an ELISA assay. Additionally, for better characterization, after each step of modification materials were subjected to SEM, FTIR-ATR, XPS and contact angle measurement analysis.

scholarly journals SYNTHESIS AND CHARACTERIZATION OF LAURYL METHACRYLATE – GRAFT - POLYPROPYLENE FIBER

2018 ◽  
Vol 54 (1A) ◽  
pp. 245
Author(s):  
Hoang Thu Ha
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Graft Polymerization ◽  
Polypropylene Fiber ◽  
Monomer Concentration ◽  
Synthesis And Characterization ◽  
Optimal Conditions ◽  
Graft Yield ◽  
Scanning Electron

The graft polymerization of lauryl methacrylate (LMA) onto polypropylene fiber (PP) was investigated by using 2,2’-azobisisobutyronitrile (AIBN) as initiator. The grafting was influenced by AIBN concentration, monomer concentration, the reaction time and reaction temperature. On the basis of a detailed investigation of these factor, the optimal conditions for the grafting of LMA onto PP with the said initiator were as follows: [AIBN] = 0.015 mol/l, [LMA] = 1.25 mol/l, reaction time 240 min, reaction temperature 80 oC, in which the graft yield (%GY) of 15.7 % was obtained. Characterization of the polypropylene fiber-graft-lauryl methacrylate was done by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).

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.

scholarly journals Synthesis of propylene carbonate from urea and 1,2-propylene glycol over metal carbonates

2011 ◽  
Vol 17 (3) ◽  
pp. 323-331 ◽  
Author(s):  
Jiancheng Zhou ◽  
Wu Dongfang ◽  
Birong Zhang ◽  
Yali Guo
Keyword(s):  
Reaction Time ◽  
Propylene Glycol ◽  
Propylene Carbonate ◽  
Reaction Temperature ◽  
Reaction Conditions ◽  
Lead Carbonate ◽  
Synthetic Process ◽  
Metal Carbonates ◽  
Optimal Reaction ◽  
Mixed Carbonate

A series of single-metal carbonates and Pb-Zn mixed-metal carbonates were prepared as catalysts for alcoholysis of urea with 1,2-propylene glycol (PG) for the synthesis of propylene carbonate (PC). The mixed carbonates all show much better catalytic activities than the single carbonates, arising from a strong synergistic effect between the two crystalline phases, hydrozincite and lead carbonate. The mixed carbonate with Pb/Zn=1:2 gives the highest yield of PC, followed by the mixed carbonate with Pb/Zn=1:3. Furthermore, Taguchi method was used to optimize the synthetic process for improving the yield of PC. It is shown that the reaction temperature is the most significant factor affecting the yield of PC, followed by the reaction time, and that the optimal reaction conditions are the reaction time at 5 hours, the reaction temperature at 180 oC and the catalyst amount at 1.8 wt%, resulting in the highest PC yield of 96.3%.

Efficient and Reusable Silica Gel Supported Metal Ionic Liquid Catalysts for Palmitic Acid Esterification to Biodiesel

2021 ◽  
Vol 43 (1) ◽  
pp. 1-1
Author(s):  
Guo Yingwei Guo Yingwei ◽  
Chen Xuedan Chen Xuedan ◽  
Yan Shiting Yan Shiting ◽  
Zhang Zhengliang Zhang Zhengliang ◽  
Chen Yuqin Chen Yuqin ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Palmitic Acid ◽  
Silica Gel ◽  
High Surface ◽  
High Surface Area ◽  
Kinetic Studies ◽  
Catalytic Performance ◽  
Reaction Conditions ◽  
Acid Esterification ◽  
Supported Metal

A series of silica gel (SG) supported metal ionic liquid catalysts (x[Bmim]Cl-CrCl3/SG) were synthesized and exploited for the esterification of palmitic acid (PA) with methanol (ML) to produce biodiesel efficiently. The 10%[Bmim]Cl-CrCl3/SG catalyst with high surface area and desirable acidity exhibited the best catalytic performance and reusability after six consecutive running cycles. Based on the response surface analysis, the optimal reaction conditions were obtained as follows: methanol/acid mole ratio = 11:1 mol/mol, catalyst amount = 5.3 wt%, reaction time = 65 min, as well as reaction temperature = 373 K, reaching to a biodiesel yield of 96.1%. Further kinetic studies demonstrated that the esterification of PA with ML obeyed 1.41 order kinetics for acid concentration with the activation energy of 16.88 kJ/mol

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