Cationic grafting from carbon black. III. Grafting of polyesters from carbon black by ring-opening polymerization of lactones initiated by CO+ClO groups on carbon black

It was found that the cationic ring-opening polymerization of δ-valerolactone (VL), ε-caprolactone (CL), and β-propiolactone (PL) was initiated by carbon black containing CO⁺ClO groups, which were introduced by the reaction of COCl groups with AgClO₄. The polyester was propagated from CO⁺ClO groups and effectively grafted onto carbon black surface. The polymerizability of these lactones by CO⁺ClO groups decreased in the following order: VL > CL > PL. The increasing temperature of the polymerization caused an increase in the rate of the chain transfer reaction of the growing chains and brought about the decrease of grafting ratio of polyester onto carbon black.     

Grafting of poly-β-alanine onto carbon black: The hydrogen transfer polymerization of acrylamide catalyzed by n-butyllithium in the presence of carbon black

The hydrogen transfer polymerization of acrylamide (AAm) catalyzed by n-butyllithium in the presence of carbon black was carried out at 80–100°C and the grafting of poly-β-alanine (nylon 3) was investigated. It was suggested that the growing polymer anion was captured by the quinonic oxygen group on the surface of carbon black. Furthermore, the growing polymer anion reacted with the phenolic hydroxyl group on the surface to give ungrafted polymer and the lithium phenolate (? O^?Li⁺) group (chain transfer to phenolic hydroxyl group). The ? O^?Li⁺ group formed was considered to be capable of initiating the hydrogen transfer polymerization of AAm. Accordingly, during the hydrogen transfer polymerization in the presence of carbon black, poly-β-alanine was effectively grafted by the termination of growing polymer anion and the propagation of the polymer from the ? O^?Li⁺ group on the surface. The grafting ratio was determined to be 60–80%. The carbon black obtained from the polymerization gave a stable colloidal dispersion in water, N,N-dimethylformamide, and formic acid. Furthermore, it was found that the ratio of hydrogen transfer polymerization to normal vinyl polymerization (T ratio) increased with an increase in polymerization temperature.     

Synthesis, Characterization and Properties of New Lauryl Amidopropyl Trimethyl Ammoniums

A new lauryl amidopropyl trimethyl ammonium methyl carbonate with the formula CH₃(CH₂)₁₀CONH(CH₂)₃N⁺(CH₃)₃CH₃CO₃ ^? was synthesized via a high pressure process with tertiary amines and dimethyl carbonate, and its chemical structure was confirmed using ¹H-NMR spectra, mass spectral fragmentation, and FTIR spectroscopic analysis. In addition, several quaternary ammonium salts with new counterions X^? (X^?=HCO₃ ^?, HCOO^?, CH₃COO^?, CH₃CH(OH)COO^?) were also synthesized by the ion exchange reaction of methyl carbonate quaternary ammoniums with corresponding acids. The surface activities of these compounds were measured, including surface tension (??), critical micelle concentration and minimum surface area (A _min) at 25?°C. Adsorption and micellization free energies of these quaternary ammonium salts in their solutions showed a good tendency towards adsorption at interfaces. The antimicrobial activities are reported for the first time against representative bacteria and fungi for lauryl amidopropyl trimethyl ammoniums. It was found that the antimicrobial potency was Gram-positive bacteria?>?fungi?>?Gram-negative bacteria.     

Alkaline hydrolysis of alkylated acidic groups on carbon black

Potentiometric pH-stat titration was performed on alkylated carbon black dispersed in aqueous solution at pH 9.0, 10.0 and 11.0 and alkaline hydrolysis rate constant of the alkylated functional groups on the carbon black was obtained therefrom. Carbon black treated with C₁-C₈n-alcohols in vapor or liquid phase was used in this experiment. Hydrolysis proceeded more rapidly for carbon black treated with lower alcohols. For each alkylated carbon black, the hydrolysis rate constant decreased with time and, after the hydrolysis rate diminished, a hydrolysis resistant fraction of alkylated groups remained. For example, the hydrolysis rate constants at 25°C were 24.33, 17.50 and 4.501 · mol^?1 · sec^?1 at 15 min and 6.00, 6.00 and 3.671 · mol^?1 · sec^?1 at 45 min after the start of hydrolysis at pH 9.0 for carbon black treated with C₂, C₃ and C₄ alcohols respectively.     

Polysulfobetaines and corresponding cationic polymers. IV. Synthesis and aqueous solution properties of cationic poly(MIQSDMAPM)

A cationic poly(methyl iodide quaternized styrene-dimethylaminopropylmaleimide) copolymer [poly(MIQSDMAPM)] was synthesized by imidizing styrene-maleic anhydride (SMA) copolymer. Its aqueous solution properties were studied by measurements of reduced viscosity, intrinsic viscosity, and a flocculation test. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentration of the added salt. “Soft” salt anions were more easily bound to the quaternary ammonium cation (R₄N⁺) of poly(MIQSDMAPM) than “hard” salt anions. Halide anions are hard anions; consequently, hard cations were more easily atracted to halide anions, and reduced binding degree of halide anion on the quaternary ammonium group (R₄N⁺). Some salt ions were observed to strongly attract the quaternary ammonium group of the cationic polymeric side chain and resulted in agglomeration of the polymers. A comparison of various flocculants as to the effect of flocculation was made in this study. © 1996 John Wiley & Sons, Inc.     

Polysulfobetaines and corresponding cationic polymers. VI. Synthesis and aqueous solution properties of cationic poly(methyl iodide quaternized acrylamide–N,N-dimethylaminopropylmaleimide copolymer) [poly(MIQADMAPM)]

The copolymer prepared by copolymerizing with acrylamide and maleic anhydride was imidized with N,N-dimethylaminopropylamine. The obtained acrylamide–N,N-dimethylaminopropylmaleimide (ADMAPM) copolymer was then reacted with methyl iodide to yield a poly(methyl iodide quaternized acrylamide–N,N-dimethylaminopropylmaleimide) copolymer [poly(MIQADMAPM)]. Its aqueous solution properties were studied by measurements of reduced viscosity, intrinsic viscosity, and flocculation test in this study. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentration of the added salt. “Soft” salt anions were more easily bound to the quaternary ammonium cation (R₄N⁺) of poly(MIQADMAPM) than were “hard” salt anions. Halide anions are hard anions; consequently, hard cations were more easily attracted to halide anions and reduced the binding degree of halide anion on the quaternary ammonium group (R₄N⁺). The intrinsic viscosity behavior for cationic polyelectrolyte resulting from the electrostatic repulsive force of the polymer chain was contrasted with polyampholyte. The effect of various flocculants on flocculation in different pH values was accessed in this study. © 1996 John Wiley & Sons, Inc.     

Fluidizing effects of polymers with various anchoring groups in cement pastes and their sensitivity to environmental temperatures

We synthesized various polymers with different functional groups of ─COO⁻, ─SO₃⁻, and ≡N⁺─ to study the impact of the environmental temperature (25, 50, and 80 °C) on the dispersing capability by measuring the fluidity of fresh cement paste, total organic carbon, ζ potential, and isothermal calorimetry. The results show that no adsorption was observed for the cement pastes containing acrylic acid, 2-acrylamido-2-methyl propane sulfonic acid, and [3-(methacryloylamino)propyl] trimethyl ammonium chloride, probably because of the trace amount of adsorption, whereas the fluidity of the pastes was indeed improved by the addition of these chemicals. Generally, for the polymers containing various functional groups, the adsorption capability was in the order ─COO⁻ > ─SO₃⁻ > ≡N⁺─. The dispersing capability for the carboxylate superplasticizer was robust to the change in the temperature, whereas it was dramatically weakened by the increase in temperature for sulfonate superplasticizer, although the adsorption amount increased along with the temperature rise. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47494.     

Aqueous solution properties of poly(trimethyl acrylamido propyl ammonium iodide) [poly(TMAAI)]

The aqueous solution properties of a cationic poly(trimethyl acrylamido propyl ammonium iodide) [poly(TMAAI)] were studied by measurements of reduced viscosity, intrinsic viscosity, and flocculation test. The reduced viscosity and intrinsic viscosity of this cationic polyelectrolyte were related to the types and concentration of added salt. “Soft” salt anions were more easily bound on the quaternary ammonium (R₄N⁺) of poly(TMAAI) than those of “hard” salt anions. Halide anions are hard anions; consequently, hard cations were more easily attracted to halide anions for reducing the binding degree of halide anion on the quaternary ammonium group (R₄N⁺). Some salt ions were observed to strongly attract the quaternary ammonium of the cationic polymeric side chain for coagulation of the polymers. This effect would make the polymeric aqueous solution become turbid. The intrinsic viscosity behavior for cationic polyelectrolyte resulting from the electrostatic repulsive force of the polymer chain is contrasted with polyampholyte. A comparison of various flocculants as to the effect of flocculation was also studied. © 1994 John Wiley & Sons, Inc.     

Raman spectra of Graphon carbon black

The Raman spectrum of Graphon carbon black has been recorded using rotating cell techniques. Angular dependence of scattering at 1360, 1580 and 2700 cm^?1 are reported and these data suggest that the 1360 cm^?1 line is associated with non-planar microstructure distortions. The excitation frequency dependence of the intensity ratio of the bands at 1360 (D) and 1580 cm^?1 (G) is interpreted in terms of resonance (vibronic) interaction. This dependence is primarily the result of an increase in the intensity of the 1360 cm ^?1 line. The disorder-associated line (D) exhibits a significant excitation-dependent shift from 1378 cm^i?1 (457.9 nm Ar⁺) to 1330 cm^?1 (647.1 nm Kr⁺). The “graphite” (G) line position is less sensitive to changes in excitation frequency. The spectral features are discussed in terms of factor group, C_6v⁴, and layer site symmetry, C_3v. Also the possible role of localized alkene-like structure in zones of structural distortion is considered.     

Glass electrode response to lithium ion activity. Effects of sodium,potassium, ammonium,tetramethyl-, tetraethyl-, and tetra-n-butyl ammonium ions in water and 50% water-ethanol mixture

Competing effects of Na⁺, K⁺, NH⁺₄ and three quaternary ammonium ions, Me₄N⁺, Et₄N⁺, and n-Bu₄N⁺, on the response of a lithium ion-selective glass electrode have been investigated in water and 50% water-ethanol mixture. The results have been analysed according to an ion-exchange model developed earlier for solutions in propylene carbonate. It appears that the effects of the two groups of cations can be rationalized in terms of the relative ease (or difficulty) or desolvation experienced by a lithium ion, in their presence, prior to its incorporation into the glass phase.     

Synthesis of bifunctional polymeric adsorbent and its application in purification of stevia glycosides

Polymeric adsorbents with both functions of adsorption and decolorization were synthesized by introducing quaternary ammonium groups (e.g. –N⁺(CH₃)₃ groups) into conventional resinic adsorbent used to adsorb stevia glycosides in production. The relation between the adsorption capacity of the bifunctional adsorbents for stevia glycosides and the structure of adsorbents, and that between the decolorization efficiency and the structure were investigated. The results revealed that the adsorption capacity for stevia glycosides decreased somewhat as the increase of the content of quaternary ammonium groups in the adsorbent, while the decolorization efficiency increased. Adsorbents containing about 0.6–0.8 mmol/g of –N⁺(CH₃)₃ groups showed both high adsorption capacity and high decolorization efficiency, and showed adsorptive selectivity for the small-sized components of stevia glycosides. Mechanism of adsorption and decolorization was also studied, and revealed that adsorption of stevia glycosides was based on hydrophobic interactions, but decolorization was based on both ion exchange and hydrophobic interactions. Introduction of –N⁺(CH₃)₃ groups into polymeric adsorbent also changed the adsorption selectivity for various stevia glycosides, and thus the bifunctional adsorbent could be used to prepare stevia glycosides with high content of rebaudioside A.     

13C n.m.r. study of raw materials for carbon black

¹³C n.m.r. spectroscopy has been applied to investigate a number of coal tar and petroleum-derived carbon black feedstocks. Application of the J-modulated spin echo technique is especially rewarding, as this method renders the quaternary carbons directly detectable. Thus the quality of carbon black feedstocks can additionally be gauged on the basis of the contents of quaternary carbons, which is a direct indication of the carbon yield in the carbon black production process.     

Viscosity of copolymers containing carbon black

The flow behavior of random copolymers of styrene and butyl methacrylate containing specific carbon blacks varying in surface area were studied at various temperatures and shear rates. Master curves of reduced viscosity as a function of shear rate were prepared for the pure copolymers at 150°C. The superposition required vertical and horizontal shifts, proportional to (a_T)^?1 and (a_T)^.53, respectively, where a_T is the shift factor. With the incorporation of carbon black, the viscous response is non-Newtonian exhibiting a yield stress at increasing filler concentration and surface area. Master curves of viscosity against shear rate were generated at fixed filler loadings and surface areas by using a single horizontal shift factor.     

Properties of the Quaternary Ammonium Salts with Novel Counterions

The Krafft temperatures, surface tensions and bacteriostatic efficacies of a series of dodecyl/tetradecyltrimethylammonium salts with new type counterions based on the general formula RN⁺(CH₃)₃?A^? were measured. The results revealed that the Krafft temperatures of the studied products were below 0?°C and the surface tensions of water were decreased to 22?C42?mN?m^?1 when applying these surfactants at a concentration range from 10^?2 to 10^?4?mol?L^?1. Moreover, the physicochemical parameters such as the saturation adsorption value, the minimum area per surfactant molecule and the standard thermodynamic parameters of adsorption and micellization varied with different counterions for these prepared quaternary ammonium salts. In addition, the bacteriostatic tests showed that the counterions with shorter carbon chain lengths were associated with greater efficacy for the novel quaternary ammonium salts studied here.     

Synthesis of novel photochromic spiropyran dyes containing quaternary ammonium salt or cinnamoyl moiety and their properties as photoinitiators

Three novel spiropyran (SP) dyes containing quaternary ammonium salt or cinnamoyl moiety were synthesized and their photosensitive properties as photoinitiator were characterized by UV–vis spectroscopy. The intramolecular electron transfer of SP dyes containing quaternary ammonium salt was much faster and can initiate the photopolymerization under UV irradiation though the photochromic properties than those of SPs containing cinnamoyl group. A photoinitiation system containing SPs and the hexaarylbisimidazoles was studies, and the initiation properties were tested by monitoring the conversion rate of double‐bond at 810 and 1640 cm^?1 with ‐time infrared spectroscopy. It was found that the system containing our SP derivatives exhibited much higher initiating efficiency than ever reported SP dyes in the photopolymerization of 2‐phenoxyethylacrylate/N‐vinylcarbazole. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

A thermosensitive chitosan/poly(vinyl alcohol) hydrogel containing nanoparticles for drug delivery

The synthesis and characterization of a thermosensitive chitosan (CS)/poly(vinyl alcohol) (PVA) hydrogel containing nanoparticles with different charges for drug delivery were reported. Through the electrostatic effect of –N⁺(CH₃)₃ and –COO⁻, the nanoparticles of N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride(HTCC)–carboxymethyl chitosan (CM) were prepared. The nanoparticles with different charges were obtained by the different ratio of –N⁺(CH₃)₃ and –COO⁻, which were suitable for drug delivery with opposite charges, such as propranolol and diclofenac sodium, respectively. The release of the positive drug was the slowest with the hydrogels containing negative nanoparticles. Similarly, the release of the negative drug was the slowest with the hydrogels containing positive nanoparticles. However, the releases of the two drugs were both the fastest with the pure hydrogels. It indicated the addition of nanoparticles was helpful to slow the suitable drug release. Though the nanoparticles did not reinforce the gel strength, the electrostatic effect between nanoparticles and drugs reduced the burst release. Therefore, the composite gels are attractive for applications as carriers for drug delivery.     

Synthesis of UV‐curable/alkali‐soluble dispersants used for black photoresist with a high loading of carbon black

This research synthesized a functional dispersant, not only providing a good dispersion of carbon black (CB) but also possessing ultraviolet (UV)‐curable and alkali‐soluble properties, by a two‐step process. Firstly, bisphenol‐A epoxy diacrylate was reacted with benzophenone tetracarboxylic dianhydride at different molar ratios to obtain UV‐curable/alkali‐soluble resins. In the second step, these resins would possess dispersion ability of CB by reaction with an isocyanate‐containing methacrylate. The prepared dispersants were evaluated by their dispersion ability and the light absorption property of CB. The results showed that one of the dispersants was able to disperse CB in the solvent up to 10 wt % with a mean particle size about 100 nm. This particular dispersant had a moderate amount of amino‐containing groups (such as urethane, amide, and imide) serving as anchoring sites on CB, and a sufficiently long chain (M_n ～ 2600) to provide a steric repulsion among CB particles. The advantage of this CB/dispersant system is that no other curable resins are needed. By using a suitable photoinitiator, the present CB/dispersant system could reach a polymerization rate of 1.05 × 10^?3 (s^–1), and a black pattern of 10 μm in width on a glass substrate was obtained through an UV‐lithography process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

A temperature-responsive carbon black nanoparticle prepared by surface-induced reversible addition-fragmentation chain transfer polymerization

A reversible addition-fragmentation chain transfer (RAFT) agent, 2-{[(dodecylsulfanyl)carbonothioyl]sulfanyl}propanoic acid (DSCTSP), was immobilized on the hydroxyl-functionalized carbon black (CB) surface via a direct condensation reaction, producing CB-DSCTSP. Then, RAFT polymerizations were carried out on carbon black surface using the CB-DSCTSP as a chain transfer agent. Poly(N-isopropylacrylamide) (PNIPAAm) chains were grown from the carbon black surface by a surface-induced reversible addition-fragmentation chain transfer (SI-RAFT) polymerization. FT-IR, ¹H NMR, TGA, TEM, and dynamic light scattering were used to characterize the carbon black grafted with poly(N-isopropylacrylamide) (CB-g-PNIPAAm). Dispersion experiment showed that CB-g-PNIPAAm had a good solubility in water. ¹H NMR, AFM and dynamic light scattering measurements showed that CB-g-PNIPAAm behaved a reversible temperature-responsive property in water.     

Synthesis and application of a cyclopolymer bearing a propylphosphonic acid and a propylcarboxylic acid pendants in the same repeating unit

Diallyl[3-(diethoxyphosphoryl)propyl](3-ethoxycarbonylpropyl)ammonium chloride [ (CH₂CH=CH₂)₂N⁺{(CH₂)₃PO₃Et₂} {(CH₂)₃CO₂Et} Cl^?], a new diallyl quaternary ammonium salt, has been cyclopolymerized to its cationic polyelectrolyte having pyrrolidine rings embedded in the polymer backbone. The polymer represents the first example of a cyclopolymer in which each repeating unit contains a propylphosphonate as well as a propylcarboxylate pendant. The hydrolysis of one, two or all the three-ester groups in the polymer afforded a series of pH-responsive macromolecules having identical degree of polymerization, which permitted a meaningful comparison of their solution behaviors. Apparent pK _as of the triprotic repeating unit have been determined to be 2.52, 5.32 for 9.02 for the functionalities –PO₃H₂, ?CO₂H, and –PO₃H^?, respectively. The completely hydrolyzed polymer containing PO₃H₂ and CO₂H groups demonstrated remarkable antiscalant behavior; at a concentration of 10 ppm, it inhibited the scaling of CaSO₄ from its supersaturated solution with an inhibition efficiency of 100 % for over 500 min. The polymer may thus be exploited as an antiscalant in reverse osmosis plants.     

Simultaneous sulfide and acetate oxidation under denitrifying conditions using an inverse fluidized bed reactor

BACKGROUND: Simultaneous removal of sulfur, nitrogen and carbon compounds from wastewaters is a commercially important biological process. The objective was to evaluate the influence of the CH₃COO^?/NO₃^? molar ratio on the sulfide oxidation process using an inverse fluidized bed reactor (IFBR). RESULTS: Three molar ratios of CH₃COO^?/NO₃^? (0.85, 0.72 and 0.62) with a constant S^2?/NO₃^? molar ratio of 0.13 were evaluated. At a CH₃COO^?/NO₃^? molar ratio of 0.85, the nitrate, acetate and sulfide removal efficiencies were approximately 100%. The N₂ yield (g N₂ g^?1 NO₃^?‐N consumed) was 0.81. Acetate was mineralized, resulting in a yield of 0.65 g inorganic‐C g^?1 CH₃COO^?‐C consumed. Sulfide was partially oxidized to S⁰, and 71% of the S^2? consumed was recovered as elemental sulfur by a settler installed in the IFBR. At a CH₃COO^?/NO₃^? molar ratio of 0.72, the efficiencies of nitrate, acetate and sulfide consumption were of 100%, with N₂ and inorganic‐C yields of 0.84 and 0.69, respectively. The sulfide was recovered as sulfate instead of S⁰, with a yield of 0.92 g SO₄^2?‐S g^?1 S^2? consumed. CONCLUSIONS: The CH₃COO^?/NO₃^? molar ratio was shown to be an important parameter that can be used to control the fate of sulfide oxidation to either S⁰ or sulfate. In this study, the potential of denitrification for the simultaneous removal of organic matter, sulfide and nitrate from wastewaters was demonstrated, obtaining CO₂, S⁰ and N₂ as the major end products. Copyright © 2008 Society of Chemical Industry