Poly(N-hydroxymethyl acrylamide-co-acrylic acid) and poly(N-hydroxymethyl acrylamide-co-acrylamidoglycolic acid): synthesis, characterization, and metal ion removal properties

Macroreticular chelating resins containing carboxylic groups, poly(N-hydroxymethyl acrylamide-co-acrylic acid) P(HMA-co-AA) and poly(N-hydroxymethyl acrylamide-co-2-acrylamido glycolic acid) P(HMA-co-AGA) were synthesized by solution radical polymerization with ammonium persulfate as initiator and N,N′-methylene-bis-acrylamide as cross-linking reagent. The polymerization yield was 98.9 and 91.9% for P(HMA-co-AA) and P(HMA-co-AGA), respectively. The retention properties were studied under competitive and noncompetitive conditions by batch equilibrium procedure for the following metal ions: Cd(II), Cr(III), Zn(II), Pb(II), and Hg(II). The effects of pH, time, temperature, and initial ion concentration on adsorption were investigated. The resins showed a significant ability to retain Pb(II), greater than 79%, at pH 5.     

Furfural-based phosphonic acid cation exchange resins from N-vinylcarbazole and its polymer. II

Thermal stabilities of the crosslinked N-vinylcarbazole/poly(N-vinylcarbazole)-furfural polymers and of the phosphonic acid resins prepared thereform were studied by thermogravimetric analysis. The overall thermal stability of the crosslinked polymers is greater than the same for poly(N-vinylcarbazole) and is further improved upon phosphorylation. The resins are stable in 5N acids and water at 100°C. Isothermal oxidative degradation studies of the resins indicate significant increase in the capacities. pH metric titration of the resins shows the presence of mono and dibasic phosphonic acid groups. The resins realize about 90% of their capacities within 2 min of equilibration.     

Novel Amine Modifiers for Unsaturated Polyester Resins

The results of studies are presented on the synthesis and functioning of amine modifiers for unsaturated polyester resins obtained by reacting ethylene oxide or propylene oxide with N,N ′‐diphenylethane‐1,2‐diamine and by reacting ethylene oxide with N,N ′‐diphenylhexane‐1,6‐diamine. When used in the amount of up to 2 wt.‐%, the amines substantially (several times) reduced the gelation time of modified unsaturated polyesters. The reactivity of resins was improved in expense of their stability.     

Epoxy resins based on aromatic glycidylamines. V. Shelf life of TGDDM-based epoxy resins

The effect of aging on resin composition was investigated as a part of a study concerned with the evaluation of epoxies containing N, N, N′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane (TGDDM). Long-term stability of three different epoxy resins based on TGDDM and their mixtures with 4,4′-diaminodiphenylsulfone (DDS) was followed at 23 ± 2°C at a relative humidity ranging from 45% to 55%, by means of GPC and HPLC; short-term stability of the resins was evaluated at 125°C.     

Preparation and evaluation of double-hydrophilic diblock copolymer as viscosity reducers for heavy oil

In this work, a series of double-hydrophilic diblock copolymers of N-acryloylmorpholine (NAMO) and N,N-dialkylacrylamide are prepared as the additives for viscosity reduction, which could effectively interact with the asphaltenes and resins. The viscosity reduction effects of the types of N,N-dialkylacrylamide monomer (N,N-dimethyl acrylamide & N,N-diethyl acrylamide) and degree of polymerization (DP) of poly(N,N-dialkylacrylamide) block in copolymers on heavy oil are tested with heavy oils with different viscosities. These viscosity reducers can work with small dosages (>25 mg L⁻¹). The interfacial tension between oil and water is significantly weakened, and the aggregating structures of asphaltenes and resins are disassembled into smaller aggregates and covered with polymers with the addition of copolymers. The re-establishment of aggregates among polar components seems to be prevented, and the stability of the heavy oil/water emulsions is greatly enhanced as a result. All these results provide the prerequisites for water-soluble diblock copolymers working as viscosity reducers for various heavy oils.     

Novel amine preaccelerators for polyester resins

The reactions between N,N‐dimethyl‐p‐phenylenediamine and ethylene or propylene oxide were carried out to obtain 3‐[p‐(N,N‐dimethylamino)phenyl]‐3‐azapentane‐1,5‐diol and 4‐[p‐(N,N‐dimethylamino)phenyl]‐4‐azaheptane‐2,6‐diol, respectively. The structures of the products were determined using elemental analysis, ¹H‐NMR and IR spectroscopy techniques. The diols were incorporated into unsaturated polyester resins. The time of gelation and stability of the resins was observed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2973–2976, 2003     

Furfural-based phosphonic acid cation exchange resins from N-vinylcarbazole and its polymer. I

Crosslinked polymers based on the condensation of furfural with N-vinylcarbazole and poly(N-vinylcarbazole) were prepared. The effect of variation of furfural concentration on the condensation of furfural with N-vinylcarbazole and its polymer was studied. The polymers were chemically modified into phosphonic acid cation exchange resins. The effects of variation of AlCl₃, PCl₃, and furfural amounts, reaction time, and rephosphorylation on the synthesis and capacities of cation exchange resins were also studied.     

Glucamine-based gemini surfactants II: Gemini surfactants from long-chain <Emphasis Type="Italic">N</Emphasis>-alkyl glucamines and epoxy resins

Gemini surfactants were synthesized by reaction of long-chain N-alkyl glucamines with epoxy resins. Analogous to the synthesis of gemini surfactns from long-chain N-alkyl glucamines and α, ω-diepoxides (1), the reaction in methanol at 70°C could be used to convert the starting materials selectively and almost quantitatively. N-Octyl glucamine, N-decyl glucamine, and N-dodecyl glucamine were combined with several epoxy resins, mainly technical glycidyl ethers of diols. Syntheses involving equimolar amounts of amine resulted in quantitative conversion of the epoxy resins, and epoxide and products could be isolated quantitatively by removing the solvent. Gemini surfactants having hydrophobic or hydrophilic spacers were preparared according to their structures and the hydrophilic properties of the epoxy resin. Surface tensions were measured, and foaming propertiers were examined to characterize surface-active properties of these surfactants. The more hydrophilic products were of particularly high surface activity. Tensiometric studies showed a reduction of surface tension to 30–34 mN/m and critical micelle concentrations in the range of 2–35 mg/L. Comparison of gemini surfactants from long-chain N-alkyl glucamines and diepoxides of α,ω-diolefins (chain lengths: C₈, C₉, C₁₀, and C₁₄) with those based on epoxy resins showed similar or lower surface activities using hydrophobic epoxy resins and much better surface-active properties using hydrophilic epoxy resins (e.g., based on glycerol). This, together with the easier availability, makes the epoxy resin-based products interesting surfactants. Products having very good surface-active properties are available, especially using glycidyl ether of aliphatic diols or glycerol.     

Modification of bismaleimide with allyl compound and N‐phenylmaleimide

Three different formulas with low‐cost resins, made up of N,N′‐bismaleimidephenylmethane (BMI), O,O′‐diallybisphenol A(BA), and N‐phenylmaleimide (NPMI) were developed. The properties of prepolymers, such as activation energies, enthalpy, and constants of reaction rate, were obtained by a kinetic programmer on DSC. Thermal and mechanical properties of neat resins were also studied. The results showed that the systems had low melting point and low viscosity. All cured resins presented excellent thermal and good mechanical properties. The mechanical properties could be affected by the quantity of NPMI and postcuring process. The water absorption is ≤1.98%; heat deflection temperature (HDT) is ≥250°C after aging for 100 h in distilled water of 90°C. The data indicate that the BMI can be effectively improved by adding BA and NPMI, while its heat resistance and hot/wet mechanical properties can be fairly retained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2518–2522, 2001     

Toughening of cyanate ester resin by N‐phenylmaleimide–N‐(p‐hydroxy)phenyl‐maleimide–styrene terpolymers and their hybrid modifiers

N‐Phenylmaleimide–N‐(p‐hydroxy)phenylmaleimide–styrene terpolymer (HPMS), carrying reactive p‐hydroxyphenyl groups, was prepared and used to improve the toughness of cyanate ester resins. Hybrid modifiers composed of N‐phenylmaleimide–styrene copolymer (PMS) and HPMS were also examined for further improvement in toughness. Balanced properties of the modified resins were obtained by using the hybrid modifiers. The morphology of the modified resins depends on HPMS structure, molecular weight and content, and hybrid modifier compositions. The most effective modification of the cyanate ester resin was attained because of the co‐continuous phase structure of the modified resin. Inclusion of the modifier composed of 10 wt% PMS (M_w 136 000 g mol^?1) and 2.5 wt% HPMS (hydroxyphenyl unit 3 mol%, M_w 15 500 g mol^?1) led to 135% increase in the fracture toughness (K_IC) for the modified resin with a slight loss of flexural strength and retention of flexural modulus and glass transition temperature, compared with the values for the unmodified resin. Furthermore, the effect of the curing conditions on the mechanical and thermal properties of the modified resins was examined. The toughening mechanism is discussed in terms of the morphological and dynamic viscoelastic behaviour of the modified cyanate ester resin system. © 2001 Society of Chemical Industry     

Epoxy resins based on aromatic glycidylamines. IV. Preparation of N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenylmethane from aniline and analysis of the product by GPC and HPLC

Epoxy resins containing N,N,N′,N′-tetraglycidyl-4,4′-diaminodiphenylmethane (TGDDM) were prepared from aniline and epichlorohydrin and analyzed by GPC and HPLC. The product composition was compared with that of resins prepared from 4,4′-diaminodiphenylmethane (DDM) and epichlorohydrin, which had been analyzed in our previous work. A new byproduct designated Y4 was isolated by semipreparative HPLC and identified by NMR and mass spectroscopy. The course of formaldehyde condensation with N,N-dichlorohydrin of aniline (DCHA) was followed by GPC and HPLC and the mechanism of formation of Y4 was proposed on the basis of obtained results. Attention was also paid to the differences in reactivity of DCHA diastereoisomers.     

Preparation and uranyl sorption of extractant resin containing ammonium groups

Summary An extractant resin was synthesized by radical polymerization of [3-(methacryloyl amino)propyl] trimethyl ammonium chloride in presence of N,N-methylene-bis-methacrylamide as crosslinker agent at different concentrations. All the resins are insoluble in water. The resins showed high affinity and selectivity for uranium. The resins do not retain significantly copper (<6%). Elution assays with sulfuric acid and sodium carbonate, were also carried out.     

Furfural-based cation-exchange resins from N-vinylcarbazole and its polymer

Cation-exchange resins have been synthesized through the condensation of N-vinylcarbazole and poly(N-vinylcarbazole) with furfural in presence of anhydrous AlCl₃ and subsequent sulfonation of the condensates. The resins have been characterized in respect to their polyfunctionality, exchange capacity, and thermal stability.     

Low‐viscosity and soluble phthalonitrile resin with improved thermostability for organic wave‐transparent composites

High processing viscosity and poor solubility limit the application of heterocyclic polymers for fabricating organic wave‐transparent composites for aerospace applications. In this paper, a novel resin, poly(phthalazinone ether bisphenol fluorene) encapped with phthalonitrile (PPEBF‐Ph), was synthesized and used as the matrix. Biphenol‐based phthalonitrile monomer BP‐Ph was also synthesized and blended with PPEBF‐Ph to further lower the processing viscosity. Solubility tests showed that the resin was soluble in dimethylformamide, N,N‐dimethyl acetamide, N‐methylpyrrolidone, dimethyl sulfoxide, chloroform, and other solvents. Differential scanning calorimetry and rheological studies revealed that the mixed resins exhibited low processing viscosity and a wide processing window below the gel temperature. Thermogravimetric analysis indicated that the cured resins were stable below 510–530 °C under nitrogen atmosphere after 6 h of curing (decreased by 40–60% compared with previous reports on phthalonitrile resin). In air, the char yields of the resins reached 20–30% when heated at 800 °C. The composites were reinforced by a quartz fiber cloth and exhibited a dielectric constant of 2.94–3.27 in an electromagnetic field with frequency ranging from 8 to 18 GHz. Retention of the bending modulus exceeded 70% at 400 °C according to dynamic mechanical analysis, indicating excellent mechanical stability was obtained. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45976.     

N-(carboxymethyl) trimellitimide–based polyesterimides as film formers for air-drying protective coatings

N-(carboxymethyl) trimellitimide, the imidodicarboxylic acid, was prepared by the reaction between trimellitic anhydride and glycine. This was subsequently condensed in N-methyl-2-pyrrolidone with the alcoholysis products obtained from linseed oil and glycerine to get different oil length polyesterimide resins. The drying characteristics of the resins and the physicochemical properties of the clear and the iron oxide pigmented coatings were evaluated. The results indicate that these materials form a promising class of film—formers for coatings of good durability and protective properties.     

Production of microporous resins for heavy‐metal removal. II. Functionalized polymers

Ion‐exchange polymers were used successfully in water‐treatment operations. In this study, three ion‐exchange resins based on 4‐vinylpyridine and divinylbenzene functionalized with N‐oxide groups were obtained. Their ion‐adsorption properties were measured in solutions containing chromium at concentrations of 4 and 500 ppm with column and batch equilibrium techniques. The removal efficiency of the chromium ions with HCl was observed to increase after the protonation of the N‐oxide groups. The resins could be reused after 10 cycles with the metal removal efficiency maintained at higher than 95%. These studies evidenced a strong correlation between the morphology and ionic group content in the resin and its chromium ion sorption capability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Cation exchange resin from phosphorylated N-vinylcarbazole formaldehyde copolymer

Crosslinked copolymers of N-vinylcarbazole and poly N-vinylcarbazole) and formaldehyde have been phosphorylated using PCl₃ and anhydrous AlCl₃ under different conditions. The cation exchange resins, thus obtained, have been characterized by elemental analyses, evaluation of total ion-exchange capacities and salt-splitting capacities, pH metric titration behavior, and IR analysis. The phosphorylated resin exhibites significantly better thermal stability than the corresponding sulfonated N-vinylcarbazole–formaldehyde cation exchange resin or the unmodified N-vinylcarbazole–formaldeyde copolymer, as well as the phosphorylated poly(N-vinylcarbazole). The phosphorylated resins also behave as polymeric dyes with pH dependent color change. Possible explanations for color change and ion-exchange capacity differences have been attempted on the basis of the structural characteristics of the resins.     

High-quality N-substituted maleimide for heat-resistant methacrylic resin

A preparation procedure for colorless, transparent N-substituted maleimide of high quality which can provide heat-resistant transparent methacryl resins was developed. N-Alkylmaleimide, the alkyl substituent of which was composed of 2 to 4 carbons, is employed, giving a polymer with enhanced heat distortion temperature (HDT) because of the higher T_g. The advantages of relatively low melting points and high vapor pressure of N-alkylmaleimide can be used for the preparation of a high-quality product with purification of the monomer by distillation. N-Isopropylmaleimide (IPMI), which fulfills these requirements, is especially useful as a monomer for transparent resins. IPMI was synthesized in a high-yield using a mixture of orthophosphoric acid and orthophosphoric acid-isopropylamine salt as catalyst. IPMI, the purity of which is 99.9 wt % or above, contains 100–200 ppm of N-isopropylmaleamic acid, maleic anhydride, dimethylmaleic anhydride, solvent, and water. IPMI, which solidifies at 25.8°C, is obtained as a colorless liquid and is freely soluble in common monomers such as methyl methacrylate (MMA), styrene (St), and acrylonitrile (AN). The obtained IPMI showed excellent thermal stability, and no quality change was observed after heating for 100 h at 50°C. The copolymer of MMA and IPMI exhibited the same YI value as a measure of coloration, and almost the same transparency as the homopolymer of MMA. An increase in IPMI content in the copolymer by 1 mol % increased the polymer T_g by 0.8°C. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1055–1062, 1997     

Introduction of two polyvinyl alcohol resins for efficient solid support Cu-catalyzed N-arylation of α-aminoacids with aryl halides in aqueous media

In this article, two polyvinyl alcohol (PVA)-based resins were prepared by crosslinking of epoxidized PVA-chains using of 4-(4-aminobenzyl)benzenamine as a crosslinker and polymerization of acrylated PVA chains in the another approach. The prepared PVA resins showed well hydrophilic and swelling properties in various organic solvents, which are used in solid-phase organic synthesis (SPOS). Swelling properties of these resins were examined in dimethylformamide, tetrahydrofuran, water, ethanol, methanol, dichloromethane, and dioxane. Furthermore, the both resins were characterized by FTIR and ¹H-NMR and their properties such as epoxy equivalent weight (EEW) of epoxidized PVA and density of the resins were determined by analytical methods. Then, α-amino acids such as L-aspartic acid, L-leucine, L-alanine, L-serine, L-valine, L-threonine, and L-tyrosine were immobilized on both resins through esterification reaction between these α-amino acids with the present hydroxyl groups on PVA resines, to carry out their solid-phase N-arylation reaction in the presence of CuI as a catalyst in milder and greener conditions than free resin protocols. Hydrolysis of the correponding N-arylated α-amino acids immobilized on the resins gave the N-arylated α-amino acids in high to excellent yields. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47597.     

Structure and Properties Relationships of Epoxy Resins Part 1: Crosslink Density of Cured Resin: (II) Model Networks Properties

Carefully designed resin precursors of high purity, viz. N,N-bis-(2,3-epoxypropyl)-N',N-dimethyl-4,4′-diaminodiphenylenemethane (G2A) and N,N-bis-(2,3-epoxypropyl)-N,N-dimethyl-4,4′-diamino-diphenylenemethane (G2S) were used in combination with N,N,N',N-tetrakis-(2,3-epoxypropyl)-4,4′-diaminodiphenylene methane, TGDDM, and cured with stoichiometric amounts of 4,4′-diamino-diphenylene methane (DDM) to produce networks with a range of controlled crosslink density. The tensile moduli E of the networks in the rubbery state, at T_g+30°C, T_g+45°C and T_g+60°C, were measured using a thermal mechanical analyser. Using the statistical theory of rubber elasticity and the observed values of E, the number average molecular weights between crosslink points M_c for the cured resins were deduced. The experimental M_c values were then compared with those derived by calculations based on a probabilistic model of the network proposed by Chu and Seferis.¹ The experimental M_c values were 2.5 to 5.5 times larger than the calculated ones. The differences were attributable to a consumption of only 40% of the available secondary amino hydrogen via epoxy-amine reaction. A direct relationship was established between the glass transition temperature and the crosslink density 1/M_c for the resins, and the dynamic mechanical properties were studied. The thermal stability of cured resins studied by thermo-gravimetric analysis indicated an enhancement of stability as 1/M_c was reduced. The amount of water absorbed by cured resin was directly proportional to 1/M_c.