Molecular weight of polyaniline synthesized by oxidation of aniline with ammonium persulfate and with ferric chloride

1995 ◽  
Vol 69 (1-3) ◽  
pp. 125-126 ◽  
Author(s):  
S. David ◽  
Y.F. Nicolau ◽  
F. Melis ◽  
A. Revillon
Keyword(s):  
Molecular Weight ◽  
Ferric Chloride ◽  
Ammonium Persulfate

Structure-Property Relationship of Dodecylbenzenesulfonic Acid Doped Polyaniline

2013 ◽  
Vol 721 ◽  
pp. 199-205 ◽  
Author(s):  
Ying Liu ◽  
Qi Wen ◽  
Jia Li Guan ◽  
Shi Jie Zhao ◽  
Qi Xing Hu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ammonium Persulfate ◽  
Degree Of Crystallinity ◽  
Structure Property ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Dodecylbenzenesulfonic Acid ◽  
Molar Ratios ◽  
Liquid Crystal Property ◽  
Relationship Of

Dodecylbenzenesulfonic acid (DBSA) doped polypanilines (PANIs) were chemically synthesized in different molar ratios of aniline (An) to ammonium persulfate (APS) and An to DBSA. The microstructures of these PANIs were investigated by means of scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared (FTIR). UV-Vis spectrometer, semiconductor parameter analyzer, ubbelohde viscometer and electrospinning technique were used to characterize the optical, electrical properties, viscosity and solubility of these PANIs. The results show that the molar rations of An to APS and An to DBSA had strong effect on the microstructure, molecular weight, degree of crystallinity, optical property, solubility and conductivity of obtained DBSA doped PANI. With the increase of the molar ratios of An to APS and An to DBSA, the conductivities and molecular weight of DBSA doped PANIs decreased, while the degree of crystallinity and solubility of DBSA doped PANIs increased. The DBSA doped PANI could dissolve in dichloromethane or HFIP and could be fabricated short fibers by electrospinning. Moreover, the solution of DBSA doped PANIs in concentrated sulphuric acid showed liquid crystal property.

Size fractionation characterisation of removed organics in reverse osmosis concentrates by ferric chloride

2011 ◽  
Vol 63 (9) ◽  
pp. 1795-1800 ◽  
Author(s):  
A. Y. Bagastyo ◽  
J. Keller ◽  
D. J. Batstone
Keyword(s):  
Molecular Weight ◽  
Reverse Osmosis ◽  
Ferric Chloride ◽  
Membrane Separation ◽  
Fulvic Acids ◽  
Cell System ◽  
Humic And Fulvic Acids ◽  
Stirred Cell ◽  
Almost All ◽  
Reverse Osmosis Concentrates

Reverse osmosis membrane separation is the leading method for manufacturing potable purified water. It also produces a concentrate stream, namely reverse osmosis concentrates (ROC), with 10–20% of the water, and almost all other compounds. One method for further treating this stream is by coagulation with ferric chloride. This study evaluates removed organics in ROC treated with ferric chloride. Fractionation with ultrafiltration membranes allows separation of organics based on a nominal molecular weight. A stirred cell system was applied for serial fractionation to classify organic compounds into six groups of <0.5 kDa, 0.5–1 kDa, 1–3 kDa, 3–5 kDa, 5–10 kDa and >10 kDa. The study found that raw ROC is rich in low molecular weight compounds (<1 kDa) with almost 50% of the organics. These compounds include soluble microbial products (SMPs) and smaller humic and fulvic acids as indicated by fluorescence scanning. Conversely, colour was mostly contributed by medium to large molecules of humic and fulvic acids (>0.5 kDa). Organics and colour were reduced in all molecular groups at an optimum treatment dose 1.48 mM FeCl3 and a pH of 5. However, ferric seemed to effectively remove colour in all size ranges while residual nitrogen was found mostly in the <1 kDa sizes. Further, the fluorescence indicated that larger humic and fulvic acids were removed with considerable SMPs remaining in the <0.5 kDa.

The influence of polymerization temperature on structure and properties of polyaniline

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Faris Yılmaz ◽  
Zuhal Küçükyavuz
Keyword(s):  
Thermal Analysis ◽  
Electrical Conductivity ◽  
Molecular Weight ◽  
Hydrochloric Acid ◽  
Liquid Medium ◽  
Thermal Studies ◽  
Ammonium Persulfate ◽  
Morphological Properties ◽  
Polymerization Temperature ◽  
Structure And Properties

AbstractThe influence of polymerization temperature (from -25 to +25 oC) on molecular weight, crystallinity, electrical conductivity, thermal and morphological properties of polyaniline has been investigated. Aniline was oxidized in an aqueous medium with ammonium persulfate and 1.0 M hydrochloric acid. The reaction mixture freezes below -10 oC and hence lithium chloride was used in sufficient amount to prevent freezing. As the reaction temperature decreases, both the molecular weight of polyaniline and its crystallinity increase. Thermal studies show a common three step decomposition pattern irrespective of the temperature used during synthesis. The morphology of polyaniline changes from granular (reaction in liquid medium) to tubular (polymerization in the frozen state). Thermal analysis indicated that the polyaniline stability increased with decreasing synthesis temperatures. Electrical conductivity of polyaniline was found to be independent of the polymerization temperature and, consequently, of the molecular weight.

scholarly journals Synthesis of hydroxyl terminated liquid natural rubber by oxidative depolymerization of deproteinized natural rubber

2016 ◽  
Vol 54 (3) ◽  
pp. 340 ◽  
Author(s):  
Le Duc Giang ◽  
Dinh Long Mong Thao ◽  
Hoang Thi Huong ◽  
Le Thi Thu Hiep
Keyword(s):  
Molecular Weight ◽  
Natural Rubber ◽  
Chemical Structure ◽  
Spectroscopic Analysis ◽  
Average Molecular Weight ◽  
Analytical Data ◽  
Ammonium Persulfate ◽  
Weight Average Molecular Weight ◽  
Liquid Natural Rubber ◽  
Deproteinized Natural Rubber

Hydroxyl terminated liquid natural rubber (HTLNR) was prepared by the depolymerization of deproteinized natural rubber (DPNR) in mixture of toluene and water at 60oC for 24 hours in the presence of ammonium persulfate as an initiator and tetrahydrofuran (THF) as a homogenizing agent. GPC analysis revealed that the number-average molecular weight (Mn) and weight-average molecular weight (Mw) of HTLNR were found to be 4.334×103 g/mol and 11.702×103 g/mol, respectively, with polydispersity index (PDI) of  2.7. The chemical structure of HTLNR was determined by FTIR and 1H-NMR and 13C-NMR spectroscopic analysis. The mechanism of depolymerization and hydroxylation of NR to form HTNR based on the analytical data is also suggested in this study.

scholarly journals Exploring the Critical Factors Limiting Polyaniline Biocompatibility

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 362 ◽  
Author(s):  
Věra Kašpárková ◽  
Petr Humpolíček ◽  
Jaroslav Stejskal ◽  
Zdenka Capáková ◽  
Patrycja Bober ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Flow Cytometry ◽  
Cell Death ◽  
Ammonium Persulfate ◽  
Low Molecular Weight ◽  
Synergic Effect ◽  
Critical Factors ◽  
Aniline Hydrochloride ◽  
Crucial Information ◽  
The Individual

Today, the application of polyaniline in biomedicine is widely discussed. However, information about impurities released from polyaniline and about the cytotoxicity of its precursors aniline, aniline hydrochloride, and ammonium persulfate are scarce. Therefore, cytotoxicity thresholds for the individual precursors and their combinations were determined (MTT assay) and the type of cell death caused by exposition to the precursors was identified using flow-cytometry. Tests on fibroblasts revealed higher cytotoxicity of ammonium persulfate than aniline hydrochloride. Thanks to the synergic effect, both monomers in combination enhanced their cytotoxicities compared with individual substances. Thereafter, cytotoxicity of polyaniline doped with different acids (sulfuric, nitric, phosphoric, hydrochloric, and methanesulfonic) was determined and correlated with impurities present in respective sample (HPLC). The lowest cytotoxicity showed polyaniline doped with phosphoric acid (followed by sulfuric, methanesulfonic, and nitric acid). Cytotoxicity of polyaniline was mainly attributed to the presence of residual ammonium persulfate and low-molecular-weight polar substances. This is crucial information with respect to the purification of polyaniline and production of its cytocompatible form.

Preparation and Properties of New Polycarboxylate-Type Superplasticizer

2011 ◽  
Vol 194-196 ◽  
pp. 1122-1125
Author(s):  
Sheng Hua Lv ◽  
Rui Jun Gao ◽  
Jian Ping Duan ◽  
Xiao Liang Yan ◽  
Ming Ming Hou
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Maleic Anhydride ◽  
Sulfonic Acid ◽  
Setting Time ◽  
Monomethyl Ether ◽  
Ammonium Persulfate ◽  
Molar Ratio ◽  
Glycol Monomethyl Ether ◽  
Relative Molecular Weight

A modified polycarboxylate superplasticizer was synthesized by copolymerization of polyethylene glycol monomethyl ether methacrylate (MPEG-MA), β–Cyclodextrins grafted maleic anhydride (MAH-β-CD), methacrylic acid (MAA) and methallyl sulfonic acid (MAS). The excellent superplasticizer was obtained at the molar ratio of n(MAH-β-CD) : n(MAS) : n(MAA) : n(MPEG-MA) was 0.05:0.1:3:1 using ammonium persulfate (APS) as initiator at 90°C for 5 h. The applied results show that the product had many advantages, such as lower dosage, longer setting time, better flow-keeping ability and better compatibility with different cement. Meanwhile, the structure and relative molecular weight were characterized by FTIR and GPC respectively.

Studies on the Realationship between the Speciation Distribution and Si/Fe Ratio of Poly-Silica-Ferric-Chloride

2010 ◽  
Vol 156-157 ◽  
pp. 1339-1342 ◽  
Author(s):  
Jian Shi ◽  
Quan Liu ◽  
Dong Sheng Wang
Keyword(s):  
Molecular Weight ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Ferric Chloride ◽  
Positive Charge ◽  
Effective Diameter ◽  
Iron Salt ◽  
Monosilicic Acid ◽  
Fe Ions

Interactions between ferric species and silica have been shown to play a large part in the coagulation of suspensions. These effects are quite distinct from those associated with polymeric or colloid silica. The interaction of monosilicic acid with Fe ions has been discussed in this paper. Compared with traditional iron salt, poly-silica-ferric-chloride (PFSC) is characterized by having higher molecular weight, less positive charge, lower Feb and higher Fec. In addition, the Si/Fe is higher and the Silica is higher and Silicc is lower. With increasing Si/Fe ratio the effective diameter of PFSC increases. Along with the increase of Si/Fe ratio, more complicated polymers are formed and the particle size distribution is broadened. Resluts show that some co-polymerized species or aggregates between silica and Fe( ) polymers are formed.

Preparation and Cement Fluidity of Slow-Release Polycarboxylate-Type Superplasticizer

2011 ◽  
Vol 399-401 ◽  
pp. 1307-1311 ◽  
Author(s):  
Xia Lv ◽  
Cheng Bing Yu ◽  
Wen Ying Qi
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Acrylic Acid ◽  
High Performance ◽  
Slow Release ◽  
Thioglycolic Acid ◽  
Ammonium Persulfate ◽  
Allyl Ether ◽  
Molecular Weight Regulator

High performance polycarboxylate-type superplasticizer (PCSP) was synthesized with acrylic acid (AA), polyethylene glycol allyl ether (APEG) and one monomer of methyl acrylate (MA), methacrylate acid (MAA), acrylamide (AM), and ethyleneglycol dimethacrylate (EGDMA). Ammonium persulfate and thioglycolic acid, as an initiator and a molecular weight regulator respectively, were used for radical polymerization in aqueous solution. Influence of superplasticizer on the cement fluidity of grout was investigated. The results showed that plasticizer admixture compounded with EGDMA-APEG-AA had excellent dispersibility and slump retention.

Ferric Chloride Coagulation for Removal of Dissolved Organic Matter and Trihalomethane Precursors

1993 ◽  
Vol 27 (11) ◽  
pp. 113-121 ◽  
Author(s):  
A. Amirtharajah ◽  
K. E. Dennett ◽  
Anne Studstill
Keyword(s):  
Molecular Weight ◽  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Humic Substances ◽  
Ferric Chloride ◽  
Fast Atom Bombardment ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Before And After

Ferric chloride coagulation of two types of natural dissolved organic matter was studied. The molecular weight distribution of Suwannee River humic substances currently used as an international standard was characterized using fast atom bombardment mass spectrometry (FABMS). The molecular weight distributions were characterized before and after coagulation. Ferric chloride dosage and pH domains on the iron coaglation diagrams were developed for removal of these humic substances and for determination of the resulting trihalomethane formation potentials (THMFP) of the treated water. The results indicate that it is possible to maximize the removal of dissolved organic matter and minimize trihalomethanes by coagulation only under very specific conditions of pH and ferric chloride dosage.

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