scholarly journals Strong Antimicrobial Activity of Highly Stable Nanocomposite Containing AgNPs Based on Water-Soluble Triazole-Sulfonate Copolymer

Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 206
Author(s):  
Alexander Pozdnyakov ◽  
Artem Emel’yanov ◽  
Anastasiya Ivanova ◽  
Nadezhda Kuznetsova ◽  
Tat’yana Semenova ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Chemical Reduction ◽  
Gel Permeation Chromatography ◽  
Radical Copolymerization ◽  
Water Soluble ◽  
Morphological Properties ◽  
Hydrodynamic Diameter ◽  
Scanning Calorimetry ◽  
Free Radical Copolymerization ◽  
Strong Antimicrobial Activity

A new hydrophilic polymeric nanocomposite containing AgNPs was synthesized by chemical reduction of metal ions in an aqueous medium in the presence of the copolymer. A new water-soluble copolymer of 1-vinyl-1,2,4-triazole and vinylsulfonic acid sodium salt (poly(VT-co-Na-VSA)) was obtained by free-radical copolymerization and was used as a stabilizing precursor agent. The structural, dimensional, and morphological properties of the nanocomposite were studied by UV–Vis, FTIR, X-ray diffraction, atomic absorption, transmission and scanning electron microscopy, dynamic and electrophoretic light scattering, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry. Hydrodynamic diameter of macroclubs for the copolymer was 171 nm, and for the nanocomposite it was 694 nm. Zeta potential for the copolymer was −63.8 mV, and for the nanocomposite it was −70.4 mV. The nanocomposite had strong antimicrobial activity towards Gram-negative and Gram-positive microorganisms: MIC and MBC values were in the range of 0.25–4.0 and 0.5–8.0 μg/mL, respectively.

Effect of Adding Electrolyte in Cement Paste on the Dispersing Force of Polycarboxylate-Type Superplasticizer

2009 ◽  
Vol 405-406 ◽  
pp. 160-165
Author(s):  
Jun Ying Lai ◽  
Xiao Qian Qian ◽  
Shu Lin Zhan ◽  
Min Hui Fang
Keyword(s):  
Free Radical ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Cement Paste ◽  
Electrolyte Concentration ◽  
Radical Copolymerization ◽  
Water Soluble ◽  
Hydrodynamic Diameter ◽  
Free Radical Copolymerization ◽  
Poly Ethylene

A series of water-soluble polycarboxylate-type superplasticizer (PCA) were synthesized by free-radical copolymerization of methyl acrylic acid and methoxy poly(ethylene glyco1) monoacrylate macromonomers in water solutions．Micelles were formed from the resultant PCA with predetermined hydrophobic and hydrophilic blocks in water. The hydrodynamic diameter and size distribution of micelles were determined by dynamic light scattering. The change of the concentration of the electrolyte results directly in the variation of the dispersing force of PCA in cement paste. The dispersing force degrades with increasing electrolyte concentration.

scholarly journals P(N-Phenylmaleimide-Alt-Styrene) Introduced with 4-Carboxyl and Its Effect on the Heat Deflection Temperature of Nylon 6

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2330 ◽  
Author(s):  
Yufei Liu ◽  
Min He ◽  
Daohai Zhang ◽  
Qian Zhao ◽  
Yang Li ◽  
...  
Keyword(s):  
Dynamic Viscosity ◽  
Gel Permeation Chromatography ◽  
Nylon 6 ◽  
Mechanical Analysis ◽  
Radical Copolymerization ◽  
Resonance Spectroscopy ◽  
Scanning Calorimetry ◽  
Free Radical Copolymerization ◽  
Ft Ir ◽  
Heat Deflection Temperature

P(N-phenylmaleimide-alt-styrene) (P(NPMI-alt-St)) and P(N-(4-carboxyphenyl)maleimide-alt-styrene) (P(CPMI-alt-St)) were designed and synthesized via free radical copolymerization. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR), gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) were used to confirm the structure of P(NPMI-alt-St) and P(CPMI-alt-St). Next, the effect of P(CPMI-alt-St) on the heat deflection temperature (HDT) of nylon 6 was studied. In comparison to the PA6/P(NPMI-alt-St) blend, with the addition of 10 wt %, the HDT value of the PA6/P(CPMI-alt-St) blend increased by 15.7 °C, and the glass transition temperature (Tg) by Dynamic mechanical analysis (DMA) increased 2.3 °C. According to the analysis of DMA, dynamic viscosity, and the SEM of PA6 and its blends, P(CPMI-alt-St) promoted its compatibility with PA6, and promoted the storage modulus and dynamic viscosity of the blends. Thus, the introduction of 4-carboxyl can significantly improve the effect of P(CPMI-alt-St) on the heat resistance modification of nylon 6.

scholarly journals Antimicrobial and anticancer activities of copolymers of tri-O-acetyl-D-glucal and itaconic anhydride

2021 ◽  
pp. 108-108
Author(s):  
Chetana Deoghare ◽  
Shruti Balaji ◽  
Savitha Dhandapani ◽  
Honey Srivastava ◽  
Anasuya Ganguly ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Gel Permeation Chromatography ◽  
Thermal Characterization ◽  
Radical Copolymerization ◽  
Dilution Method ◽  
Anticancer Activities ◽  
Scanning Calorimetry ◽  
Free Radical Copolymerization ◽  
Itaconic Anhydride ◽  
Ferrier Rearrangement

This paper reports the synthesis and characterization of monomers itaconic anhydride (IA) and tri-O-acetyl-D-glucal (TAG) as well as 4,6-di-O-acetyl-D-glucal (PSG). The homopolymers and copolymers of IA and TAG were synthesized via free radical copolymerization in bulk using azobisiso-butyronitrile as an initiator using different feed ratios of monomers. Their structural, molecular, and thermal characterization was done using 1H-NMR spectroscopy, gel permeation chromatography, and differential scanning calorimetry, respectively. The glass transition temperature (Tg) of copolymers was found in the range of 139-145 ?C. The highest Tg was found for IA-TAG2 copolymers, whereas IA-TAG4 copolymer showed lowest Tg. The molecular weight of the copolymers was in the range 5157-5499 g mol-1. The monomer TAG undergoes Ferrier rearrangement in water to give PSG. The antimicrobial activity of IA, TAG, PSG and IA-TAG copolymers was studied using the minimum microbicidal concentration-broth dilution method. TAG, IA, and PSG, as well as homopolymer and copolymers of IA and TAG are excellent antimicrobial agents.

scholarly journals Synthesis and characteristics of novel azo-based diblock copolymers and their self-assembly behavior via solvents and thermal annealing

e-Polymers ◽  
2017 ◽  
Vol 17 (6) ◽  
pp. 523-535 ◽  
Author(s):  
Athmen Zenati ◽  
Yang-Kyoo Han
Keyword(s):  
Self Assembly ◽  
Nematic Phase ◽  
Weight Control ◽  
Liquid Crystalline ◽  
Diblock Copolymers ◽  
Raft Polymerization ◽  
Gel Permeation Chromatography ◽  
Kinetic Studies ◽  
Morphological Properties ◽  
Scanning Calorimetry

AbstractA series of azo-based diblock copolymers (DBCs) with various compositions were successfully synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization in anisole with PCAEMA-CTA (macro-CTA), DOPAM (new acrylamide monomer) and AIBN (initiator). Kinetic studies on diblock copolymerization manifested a controlled/living manner with good molecular weight control. Structures and properties of monomers and DBCs were determined by 1H nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). Liquid crystalline (LC) phases and morphological properties were investigated using optical polarizing microscope (OPM), atomic force microscopy (AFM), scanning electron microscopy (SEM) and small-angle X-ray scattering (SAXS). Experimental results demonstrated that the prepared PCAEMA-CTA and DBCs possessed low polydispersity index (≤1.37). All DBCs revealed sharp endothermic transition peaks corresponding to the smectic-to-nematic phase. DBCs with high azo contents showed batonnet textures of the smectic phase whereas DBCs of low azo segments displayed threaded textures of the nematic phase. DBC with 49 wt% of azo side-chains generated a lamellar compared to DBCs with low azo block (≤41 wt%) or non-azo block (≤38 wt%) which produced hexagonal-type nanostructures. In addition, all DBCs exhibited reversible trans-cis photoisomerization behavior under UV irradiation and dark storage at different intervals of time.

scholarly journals EXTRACTION AND REEXTRACTION OF HISTIDINE AND RIBOFLAVIN BY N-VINYLCAPROLACTAME COPOLYMERS WITH 1-VINYL- AND 1-METHACRYLOYL-3,5-DIMETHYLPYROZOLE

2018 ◽  
Vol 59 (7) ◽  
pp. 55
Author(s):  
Maria S. Lavlinskaya ◽  
Gennadiy V. Shatalov ◽  
Nadezhda Ya. Mokshina ◽  
Oksana A. Pakhomova ◽  
Vyacheslav A. Kuznetsov
Keyword(s):  
Free Radical ◽  
Uv Spectroscopy ◽  
Aqueous Media ◽  
Radical Copolymerization ◽  
Water Soluble ◽  
Solution Temperature ◽  
Free Radical Copolymerization ◽  
Critical Solution Temperature ◽  
Two Phases ◽  
Degree Of Extraction

Copolymers of N-vinylcaprolactam (VC) with 1-vinyl-3,5-dimethylpyrazole (VDMP) and 1-methacryloyl-3,5-dimethylpyrazole (MDMP) were synthesized by free radical copolymerization  in dioxane with azodiisobutironitrole as initiator. Both water-soluble and water-insoluble copolymers were obtained. The copolymers compositions were determined by FTIR and UV-spectroscopy. The copolymerization constants were calculated and they were: for VC (М1)–VDMP, r1 = 0.65 ± 0.03, r2 = 0.43 ± 0.03; for VC (М1)–MDMP, r1 = 0.79 ± 0.04, r2 = 0.21 ± 0.02. These values show that VC (М1) exhibits somewhat higher activity compared to М2 and that the tendency toward alternation of comonomer units is more pronounced in VC–MDMP copolymers (r1r2 = 0.17) compared to VC–VDMP copolymers (r1r2 = 0.27). It was found that VC–VDMP copolymers are water-soluble at VC content higher than 75 mol %, and VC–MDMP copolymers at VC content higher than 88 mol %. The water-soluble copolymers based on VC have lower critical solution temperature. Their values are in range of 54-69 °C. Two-phases water-salts systems based on synthesized water-soludle thermoresponsive copolymers are proposed for histidine and riboflavin (re)extraction in aqueous media. It was found that extraction systems based on VC-VDMP copolymers are more efficient then VC-MDMP systems. Degree of extraction for both substances in a case of VC-VDMP copolymers achieved 96%. Reextraction carried out by thermoprecipitation of VC (co)polymers. It was shown that reextraction is more efficient at pH 7.6 and its degree achieved 61.7 % for histidine.

Free Radical Copolymerization of Acrylamide and Linalool with Functional Group as a Pendant

2003 ◽  
Vol 15 (3) ◽  
pp. 243-257 ◽  
Author(s):  
Anjali Shukla ◽  
A. K. Srivastava
Keyword(s):  
Functional Group ◽  
Gel Permeation Chromatography ◽  
Radical Copolymerization ◽  
Amide Group ◽  
Gravimetric Analysis ◽  
Free Radical Copolymerization ◽  
Alternating Copolymer ◽  
Analysis Technique ◽  
The Fourier Transform ◽  
The Ideal

Linalool (LIN) and acrylamide (AM) have been copolymerized by benzoyl peroxide (BPO) in xylene at 75°C for 40 min. The system follows the ideal kinetics with bimolecular termination and results in the formation of nearly alternating copolymer as evidenced from the reactivity ratios, r1(AM) = 0.3 and r2(LIN) = 0.05, which have been calculated by the Kelen-Tudos method. The overall activation energy of copolymerization is 40 kJ mol−1. The Fourier transform infrared spectrum of the copolymer shows the presence of the band at 3395 cm−1 due to the alcoholic group of LIN and at 1453 cm−1 due to the amide group of AM. The 1HNMR spectrum shows peaks at 7.0-7.7δ due to the alcoholic group of LIN and at 6.3-7.0δ due to the amide group of AM. The Alfrey-Price Q- e parameters for LIN have been calculated as Q2 = 0:274 and e2 = −0.749. The mechanism of copolymerization has been elucidated. In this paper we also report on the measurement of Mark-Houwink constants in tetrahydrofuran (THF) at 25°C by means of gel permeation chromatography (GPC) as α = 0.50 and K = 7.5 × 10−4 dl g−1. The thermal decompositions of the copolymer are established with the help of the thermal gravimetric analysis technique.

Preparation of PEG-rosin derivative for water soluble rosin flux

2016 ◽  
Vol 28 (4) ◽  
pp. 188-200 ◽  
Author(s):  
Kanlaya Phaphon ◽  
Sumrit Wacharasindhu ◽  
Amorn Petsom
Keyword(s):  
Large Scale ◽  
Gel Permeation Chromatography ◽  
Water Soluble ◽  
Molar Ratio ◽  
Scale Production ◽  
Solder Paste ◽  
Scanning Calorimetry ◽  
Corrosion Properties ◽  
Synthetic Process ◽  
Content Type

Purpose This study aims to synthesize polyethylene glycol (PEG)-rosin derivatives from rosin and PEG for the production of solid soldering fluxes. The PEG-rosin derivatives would be water soluble, and the resulting solid soldering fluxes would have reasonable wetting ability when combined with a low-halide-content activator. Design/methodology/approach This paper presents a synthetic process for PEG-rosin derivatives. The reaction conditions (including catalyst type, catalyst concentration, reaction temperature and PEG type) were optimized for the synthesis of PEG-rosin derivatives. The chemical and physical properties of PEG-rosin derivatives were characterized by Fourier transform infrared spectroscopy, carbon-13 nuclear magnetic resonance spectrometry, differential scanning calorimetry and gel permeation chromatography. The production and characteristics of water-soluble rosin fluxes (WSRFs) were studied according to the standards of the Japanese Industrial Standards (JIS) Committees. Findings WSRs were successfully synthesized from rosin and PEG using 2 per cent ZnO as a catalyst, with a 2:1 molar ratio of rosin:PEG at 250°C over 9 h. The resulting WSRs were completely soluble in water. As the PEG3000-rosin had the highest melting point (55.2°C), it was chosen for the preparation of the WSRFs. Activators such as succinic acid, glutaric acid, ethylamine hydrochloride and diethylamine hydrobromide were selected for use in the production of the fluxes. It was found that WSRF 09 and WSRF 04 gave the best performance with the lead-free Sn-0.7Cu solder alloy in terms of good solderability, low halide content (less than 1,500 ppm), high insulation resistance and low corrosion. These fluxes were applied to produce solder pastes with Sn-3.0Ag-0.5Cu alloy and they passed the performance tests as expected for solder paste. Research limitations/implications Further studies are necessary on large-scale production and to compare the performance of these fluxes to those from conventional water-soluble fluxes currently available in the market. Application of these fluxes on low-temperature solder alloys such as SnZn and SnBi (Ren et al., 2016) worth further study. Originality/value The classification of flux systems according to the JIS 3283 standard does not specify PEG-rosin derivatives in the flux; nevertheless, ranking of the flux systems based on the halide content and corrosion properties of activators would be useful information when selecting flux systems for electronics soldering in water-washable applications. The application of these fluxes in solder paste gave very promising results and is worth investigating into more detail, as well as field test.

Miniemulsion Polymerization Stabilized by a Well-Defined, Amphiphilic Gradient Poly(styrene-co-acrylic acid) Copolymer

2006 ◽  
Vol 59 (8) ◽  
pp. 544 ◽  
Author(s):  
Catherine Lefay ◽  
Maud Save ◽  
Bernadette Charleux ◽  
Stéphanie Magnet
Keyword(s):  
Particle Size ◽  
Acrylic Acid ◽  
Methyl Methacrylate ◽  
Butyl Acrylate ◽  
Miniemulsion Polymerization ◽  
Radical Copolymerization ◽  
Water Soluble ◽  
Size Distributions ◽  
Particle Size Distributions ◽  
Free Radical Copolymerization

The nitroxide-mediated controlled free-radical copolymerization of styrene (St) and acrylic acid (AA) was used to synthesize a well-defined poly(St30%-co-AA70%) amphiphilic gradient copolymer. The latter proved to be an efficient stabilizer in the 45 wt.-% solids content, batch miniemulsion polymerizations of St and of mixtures of methyl methacrylate/n-butyl acrylate (35/65 w/w). With 2,2´-azobisisobutyronitrile as an oil-soluble initiator, polystyrene latexes with a very narrow particle distribution were obtained, whereas the water-soluble initiator, potassium persulfate, led to broad, multimodal particle size distributions. Such results were explained by the contribution of two nucleation mechanisms: droplet nucleation and homogeneous nucleation. In contrast, the poly(methyl methacrylate-co-n-butyl acrylate) latexes exhibited larger particle size and narrower particle size distributions with persulfate initiator, than the polystyrene latexes.

scholarly journals Synthesis, Characterization and Copolymerization of N-(phenylamino)maleimide with MMA

2007 ◽  
Vol 4 (2) ◽  
pp. 265-271
Author(s):  
B. L. Hiran ◽  
S. N. Paliwal ◽  
Jyoti Choudhary ◽  
P. R. Choudhary
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Density Measurement ◽  
Gel Permeation Chromatography ◽  
Radical Copolymerization ◽  
Free Radical Copolymerization ◽  
H Nmr ◽  
Gel Permeation ◽  
Ft Ir ◽  
Thermal Stability Of

The free radical copolymerization of N-(phenylamino)maleimide (N-PAMI) was carried. The copolymerization with methyl methacrylate (MMA) was performed at 65°C with AIBN as the initiator in THF solvent. Resulting copolymer was characterized by density measurement, intrinsic viscosity, solubility, FT-IR &1H NMR spectroscopy. Effect of the solvent and time on copolymer yield was also investigated. The molecular weight of copolymer was determined by gel permeation chromatography (GPC). The thermal stability of copolymer was determined by Thermogravimetric analysis (TGA).

scholarly journals Sulfur/Organic Copolymers as Curing Agents for Rubber

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 870 ◽  
Author(s):  
Jakub Wręczycki ◽  
Dariusz Bieliński ◽  
Rafał Anyszka
Keyword(s):  
Mechanical Properties ◽  
Crosslink Density ◽  
Elemental Sulfur ◽  
Freezing Point ◽  
Petroleum Industry ◽  
Polymeric Materials ◽  
Mechanical Analysis ◽  
Radical Copolymerization ◽  
Scanning Calorimetry ◽  
Free Radical Copolymerization

It is widely acknowledged that waste sulfur generated from the petroleum industry creates huge storage and ecological problems. Therefore, the various methods of utilization are becoming increasingly attractive research topics worldwide. The thermal ability of elemental sulfur to homolytic cleavage of S8 rings enables its free radical copolymerization with unsaturated organic species and the obtaining of chemically stable polymeric materials. Here we report a novel possibility to use sulfur/organic copolymers obtained via “inverse vulcanization” as curatives for rubber. For this purpose, several various sulfur/organic copolymers were synthesized and analyzed from the point of view of their performance as rubber crosslinking agents. Solvent extraction was used to purify sulfur/organic copolymers from unreacted (elemental) sulfur. Thermal properties of the prepared copolymers were characterized by thermogravimetric analysis and differential scanning calorimetry (TGA–DSC). Crosslink density and structure of cured elastomers was studied by equilibrium swelling, thiol-amine analysis and freezing point depression. Mechanical properties of the vulcanizates were determined under static and dynamic conditions (DMA—dynamic mechanical analysis). It is proved that the utilization of sulfur/organic copolymers as curatives enables an effective crosslinking process of rubbers. Taking into account the results of a crosslink density analysis and mechanical properties of the vulcanizates cured with purified copolymers, it is evident that relatively long copolymer macromolecules are also involved in the formation of chemical bonds between unsaturated rubber macromolecules.

Sign in / Sign up

Export Citation Format

Share Document