Reaction of aliphatic tertiary amines with hydroperoxides

Trioctylamine acts as an antioxidant in fats at 70C but not at lower temperatures. A reactive antioxidant intermediate was sought. Dioctylhydroxylamine was obtained from the reaction of trioctylamine and t-butyl peroxide at 70C. The recrystallized product had antioxidant properties. About 0.1% existed as stable free radical by electron-spin resonance. Didecyl- and didodecylhydroxylamines were also synthesized from the corresponding tertiary amines. These and a sample of commercial diethylhydroxylamine also contained free radicals and possessed antioxidant activity.     

Step-growth polymerization of unsaturated aldehydes with aliphatic amines

The step-growth polymerization of unsaturated aldehydes (acrolein, crotonaldehyde, cinnamaldehyde) and aliphatic amines (butylamine, ethylenediamine, triethylenetetramine, diethylenetriamine, hexamethylenediamine) took place intensively in the temperature range between 50 and 90°C. The rates of individual reactions depended on the type of individual aldehydes and amines. The quantity of individual unreacted monomers was mostly under 1%. The average molecular weights of oligomers were between 290 and 710. The individual resins consisted of oligomers with free ? OH, ? NH, ? CH?N? , and ? CH?CH? groups, which are further able to cross-link the resins with three blocked isocyanate to insoluble, elastic film with high adhesion to glass and metal substratum. © 1994 John Wiley & Sons, Inc.     

Reactions of phenolic ester alcohol with aliphatic isocyanates—transcarbamoylation of phenolic to aliphatic urethane: A 13C‐NMR study

Reactions of aliphatic isocyanates with a phenolic ester alcohol (PHEA) were investigated using ¹³C‐NMR spectroscopy. PHEA has two reactive sites: a phenolic  OH group and a secondary aliphatic  OH group. Both  OH groups react with the isocyanate groups. With an organotin catalyst, dibutyltin dilaurate (DBTDL), the aliphatic  OH group reacts first. With a tertiary amine catalyst, 1,4‐diazabicyclo[2.2.2]octane (DABCO), or triphenylphosphine (Ph₃P) or even in the absence of a catalyst at room temperature (RT) the phenolic  OH group reacts first. With the organotin catalyst, the reactions are generally complete in a day at RT. With DABCO or triphenylphosphine or DNNDSA catalysts, the reactions are almost complete only in 3–4 days at RT in ethyl acetate or acetonitrile. Uncatalyzed reactions are slower. With an acid catalyst such as dinonylnaphthalenedisulfonic acid (DNNDSA), both  OH groups react with the isocyanate. When equimolar quantities of PHEA and hexamethylenediisocyanate (HDI) polymerize at RT or reflux in the presence of a catalyst, both  OH groups react, with the phenol reacting slowly. Upon refluxing, the phenolic  OH‐based urethane slowly rearranges (transcarbamoylation) to the aliphatic  OH‐based urethane. DABCO and Ph₃P catalysts effect this rearrangement at a much slower rate than does the acid catalyst. In the presence of a catalytic amount of DBDTL in a refluxing solvent, this rearrangement is complete in 2 h. By refluxing the phenolic–OH‐based urethane in isopropanol, the mechanism of transcarbamoylation was found to be intermolecular. The mechanism is likely to involve deblocking of the phenolic urethane and subsequent reaction of the isocyanate generated, with the aliphatic  OH group. This conclusion was confirmed by differential scanning calorimetry (DSC) experiments. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2212–2228, 2000     

Reaction of azo derivatives of acetoacetanilide with aliphatic amines

Azoacetoacetanilides condense with primary aliphatic amines to give azoaminocrotoanilides (I). Comparison of the infra-red and nuclear magnetic resonance spectra with those of model compounds leads to the proposal of formulae of type (VI) as a refinement of formula (I).      

Characterization and modeling of diglycidyl ether of bisphenol‐a epoxy cured with aliphatic liquid amines

The characterization by DMA and compressive stress‐strain behavior of an epoxy resin cured with a number of liquid amines is studied in this work along with predictions of the associated properties using Group Interaction Modeling (GIM). A number of different methods are used to assign two of the input parameters for GIM, and the effect on the predictions is investigated. Excellent predictions are made for the glass transition temperature, along with good predictions for the beta transition temperature and modulus for the majority of resins tested. Predictions for the compressive yield stress and strain are less accurate, due to a number of factors, but still show reasonable correlation with the experimental data. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3130–3141, 2013     

The solubility of hydrogen in aliphatic amines

The solubility of hydrogen in ammonia, monomethylamine, monoethylamine and n-propylamine was determined at temperatures from ?70°C to 25°C and in 1,2-propanediamine and 1,2-ethanediamine over the temperature ranges ?25°C to 11°C and 25°C to 34°C respectively. Measurements were made at total pressures up to 300 psig. The solubility data were correlated in terms of Henry's law and the solubilities are in the range 1 × 10^?5 to 3 × 10^?4 mole fraction at a hydrogen partial pressure of 1 atmosphere. The measured solubility data were used to extend a correlation proposed by Yen and McKetta. This revised correlation may be used to estimate the solubility of hydrogen in polar, associated amines.     

Fluorescence and IR characterization of epoxy cured with aliphatic amines

Cure reactions of the stoichiometric mixtures of diglycidyl ether of bisphenol A (DGEBA) and two very low molecular weight aliphatic polyether diamines (PED) were studied by using fluorescence and mid- and near-IR spectroscopic techniques. As the cure proceeded, the primary amine groups in PED are converted to the secondary and the tertiary amines. Near-IR spectral analysis was used to calculate the concentration of the three amine groups as a function of cure time. The decrease in the fluorescence intensity of DGEBA at about 307 nm was observed due to more effective quenching of the tertiary amine groups in PED, in comparison to the primary and the secondary amine groups. A large decrease in fluorescence intensity at 75 and 95 °C cure was observed. The amount of all the amine species was estimated from NIR spectra to shed light on the cure kinetics of PPO (polypropylene oxide) in comparison with PEO (polyethylene oxide) epoxy, as well as to explain their fluorescence behavior.The fluorescence intensity changes were correlated to the extent of epoxy reaction obtained by mid- and near-IR spectroscopy.     

Study of lactic acid extraction with higher molecular weight aliphatic amines

Lactic acid extraction was studied with two extractants, trioctyl amine (TOA) and Aliquat 336, in three diluents (methylisobutyl ketone (MIBK), octanol and paraffin liquid). The effects of organic phase extractant concentration and aqueous phase pH on the extraction process were examined. Among the extractants, TOA was found to be a better extractant than Aliquat 336 in all the diluents. In experiments with 50% (v/v) TOA in methylisobutyl ketone, 79% lactic acid could be extracted (initial lactic acid concentration 86·96 g dm⁻³). MIBK had a profound effect on the extraction behaviour of TOA in comparison with octanol and paraffin liquid while none of the diluents affected the extraction with Aliquat 336. The extraction of lactic acid was favoured at low pH. The toxicities of TOA and the diluents to Lactobacillus rhamnosus NRRL B445 were also studied. While TOA was found to be highly toxic at the molecular and the phase level, the paraffin liquid was totally non-toxic. The extraction of glucose and yeast extract by TOA and the diluents used was found to be low, which thus enables the selective extraction of lactic acid. © 1998 SCI     

On the modelling of multicomponent acid extraction with long-chain aliphatic amines

The solvent extraction of phosphoric, hydrochloric, sulphuric, hydrofluosilicic and hydrofluoric acids with long-chain aliphatic amins is modelled. Pure acid equilibria are based on existing isotherms or calculated extraction constants when only experimental data are available. For binary mixtures binary combinations of acid complexes are added. In the aqueous phase Bromley's model for electrolytes is used for calculation of ionic activity coefficients and the appropriate association/dissociation equilibria taken into account for calculation of ionic strength. For the organic phase an empirical model for the non-ideal behaviour of phosphoric acid is used. For multicomponent mixtures at low acid concentrations the model calculates the extraction of phosphoric, hydrochloric and sulphuric acid almost quantitatively. For hydrofluosilicic and hydrofluoric acid the calculations are less precise and further information is needed about the different fluoride exchange equilibria involved.     

Cation exchange resin catalyzed hydroamination of vinylpyridines with aliphatic/aromatic amines

A simple and efficient protocol has been developed for hydroamination of vinylpyridines catalyzed by cation exchange resins as a heterogeneous, recyclable and environmentally benign catalyst under milder reaction conditions. The catalytic activity of various macroreticular/gel type cation exchange resin was evaluated and Amberlyst-15/Nafion-NR50 were found to provide yields in the range of 90%. The protocol was successfully applied for pyridylethylation of wide variety of aryl/alkyl amines having different steric and electronic properties.     

巯基取代的脂肪族醛的高效合成

以溴代丁酸乙酯为原料,经过苯硫酚发生亲核取代,氢化铝锂还原,PCC氧化,以总收率87%获得最终产物,其结构经过1H NMR和MS表征。     

Polymeric amines by chemical modifications of alternating aliphatic polyketones

Alternating, aliphatic polyketones were chemically modified by using di‐amines to obtain polymeric products having pendant amino groups. The used reaction, Paal‐Knorr, involves the formation of pyrrole rings along the polyketone backbone. The corresponding kinetics and final conversions are clearly dependent, among others, on statistical factors (two adjacent carbonyls must react in order to obtain ring formation) as well as on the steric hindrance (sterically hindered amino groups react very slow). The corresponding reaction products (polymeric amines) display very interesting physical properties in aqueous solution. These have been characterized by using dynamic light scattering, Cryo‐electron microscopy, fluorescence techniques, etc. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

由烯烃直接胺化合成脂肪胺的研究进展

烯烃与氨或胺直接胺化合成脂肪胺的反应在热力学上是有利的,但在动力学上需要适宜的催化剂进行活化。多种均相催化剂和多相催化剂已被尝试用于此反应,其中酸性沸石催化剂在催化氨与小分子烯烃(主要是乙烯和异丁烯)的反应中表现出了较好的活性和很高的选择性,且清洁无污染。提出应通过对此反应机理的深入研究以筛选出新的、高选择性的沸石催化剂以提高反应的转化率。     

Interaction of cetyltrimethylammonium bromide with drug in aqueous/ electrolyte solution: A combined conductometric and molecular dynamics method study

Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of different salts(NaCl,KCl as well as NH_4Cl)over the temperature range of 298.15–323.15 K at the regular interval of 5 K.CFH drug has been suggested for the treatment of bacterial infections such as urinary tract infections and acute sinusitis.A clear critical micelle concentration(CMC)was obtained for pure CTAB as well as(CFH+CTAB)mixed systems.The decrease in CMC values of CTAB caused by the addition of CFH reveals the existence of the interaction between the components and therefore it is the indication of micelle formation at lower concentration of CTAB and their CMC values further decrease in attendance of salts.A nonlinear behavior in the CMC versus T plot was observed in all the cases.The ΔG_m~0 values are found to be negative in present study systems demonstrated the stability of the solution.The values of ΔH_m~0 and ΔS_m~0 reveal the existence of hydrophobic and electrostatic interactions between CFH and CTAB.The thermodynamic properties of transfer for the micellization were also evaluated and discussed in detail.Molecular dynamic simulation disclosed that environment of water and salts have impact on the hydrophobic interaction between CFH and CTAB.In water and salts,CTAB adopts spherical micelle in which charged hydrophilic groups are interacted with waters whereas hydrophobic tails form the core of the micelle.This hydrophobic core region is highly conserved and protected.In addition,micelle formation is more favorable in aqueous Na Cl solution than other solutions.     

Spacer-chromoionophores — polymethine dye substituted aza-crown ethers with increased complexation ability

Aromatic aldehyde derivatives of N-phenyl-aza-15-crown-5 ( 2 ), N-phenyl-aza-18-crown-6 ( 8 ), and benzo-15-crown-5 ( 10 ) are condensed with malononitrile and 2-amino-1,1,3-tricyano-1-propene to give light yellow to orange colored crown ether derivatives 4 , 5a , 9a , 11 , and 12 . 5a and 9a were acylated with ethyl chloroformate to give the magenta colored dyes 5b and 9b , respectively. By condensation of N-(4-nitrosophenyl)-aza-15-crown-5 3 with 2-amino-1,1,3-tricyano-1-propene the magenta dye 6a is obtained. Acylation of 6a with ethyl chloroformate leads to the deep blue colored dye 6b . In these derivatives the nitrogen or oxygen atoms of the crown ethers are part of the chromophoric system, and binding properties are affected. Further chromophoric derivatives of aza-crown ethers are studied in which these are separated from the chromophoric moiety by a spacer. N-(ω-chloroalkyl)-N-alkylanilines 14a-c were attached to aza-15-crown-5 13a-c and aza-18-crown-6 13b-c to yield the spacer crown ether derivatives 15a-c and 16a-c , respectively. The formylated spacer crown ether derivatives 17a-c and 18b were condensed with 2-amino-1,1,3-tricyano-1-propene to give the orange spacer-chromoionophores 19a-c and 20 . In these crown ether derivatives the extended conjugation is interrupted by the spacer, and good binding properties are obtained. The complex formation constants of the crown ether derivatives with Na⁺ and K⁺ are determined using ¹H NMR spectroscopy.     

Synthesis of amines from higher aliphatic esters,ammonia and hydrogen

• 1.1. A study was made of the effect of operational parameters on amination of esters on a fused iron catalyst. Conditions were found to obtain aliphatic amines with a yield of up to 85–86%.
• 2.2. During amination of aliphatic esters both the acid and the alcoholic group of the initial ester take part in the formation of amines.

     

Mechanical properties of epoxy networks based on DGEBA and aliphatic amines

The mechanical properties of epoxy networks based on diglycidyl ether of bisphenol A epoxy resin cured with various linear aliphatic amines, such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and cyclic amines such as 1‐(2‐aminoethyl)piperazine and isophorone diamine, were studied. General characteristics such as T_g, density, and packing density, were determined and related to the structure and funcionality of the curing agent. Dynamic mechanical spectra were used to study both the α and β relaxations. Tensile and the flexural tests were used to determine the Young's and flexural modulus, and fracture strength all in the glassy state. Furthermore, linear elastic fracture mechanics was used to determine K_IC. As a rule, isophorone diamine network presented the higher tensile and flexure modulus while 1‐(2‐aminoethyl)piperazine gave the highest toughness properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Isocyanates,aminoisocyanates and amines from fires—a screening of common materials found in buildings

Isocyanates, aminoisocyanates and amines were quantified from the combustion of 24 different materials or products typically found in buildings. Small‐scale combustion experiments were conducted in the cone calorimeter, where generally well‐ventilated combustion conditions are attained. Measurements were further made in two different full‐scale experiments. Isocyanates and amino‐compounds were sampled using an impinger‐filter sampling system with a reagent solution of di‐n‐butylamine in toluene. Filter and impinger solution were analysed separately using LC‐MS technique. Further the particulate distribution in the smoke gases was determined by impactor technique, and selected gaseous compounds quantified by FTIR. It was found in the small‐scale that isocyanates were produced from the majority of the materials tested. The highest concentration was found for glass wool insulation, and further high concentrations were found for PUR products, particleboard, nitrile rubber and melamine. Lower concentrations were found for wood and cable‐products. Amino‐isocyanates and amines were generally found from PUR products only. The distribution of isocyanates between the particulate‐ and fluid phases varied for the different materials and a tendency to enrichment of particles was seen for some of the materials. Further, when comparing the potential health hazard between isocyanates and other major fire gases (based on NIOSH IDLH‐values) it was found that isocyanates in several cases represented the greatest hazard. Copyright © 2003 John Wiley & Sons, Ltd.     

Interaction of a phosphorus‐based FR,a nanoclay and PA6—Part 1: Interaction of FR and nanoclay

The thermal decomposition of organophosphorus fire‐retardant (OP1311) and/ or organonanoclay (Cloisite 30B) is hereby investigated employing thermogravimetric analysis (TGA), to give an insight into their intrinsic behaviour and interaction in polymer nanocomposites for fire safety applications, because the addition of OP1311 and Cloisite 30B in Polyamide 6 (PA6) seems to have a synergistic effect on the thermal decomposition of PA6 (part 2 of the paper). An important objective of this research was to determine to what extent phosphorus components escape in the gaseous phase, which will affect the heat of combustion of the fire‐retarded polymer. The decomposition products arising from pyrolysis and combustion are investigated by means of Fourier transform infrared spectroscopy. Under pyrolytic conditions, the inclusion of Cloisite 30B into OP1311 (FR) shows a synergistic effect on the initial mass loss at low temperature of ～280–420°C and leads to the acceleration of the thermal degradation process. While the DTG curve of Cloisite 30B shows two distinct degradation peaks (steps) that of OP1311 and OP1311 plus Cloisite 30B show four degradation steps. TGA measurements of OP1311 in nitrogen show more mass loss than in air, whereas Cloisite 30B gives similar amounts of mass loss in air and nitrogen. In nitrogen, the major evolved gaseous species from Cloisite 30B alone are hydrocarbons, 2‐(diethylamino)ethanol and water, whereas the evolved gases from that of OP1311 at ～320°C are mainly water, at ～420°C, carbon dioxide, water and ammonia and at 480–570°C diethylphosphinic acid. Under thermo‐oxidative conditions, the gases evolved are mainly carbon dioxide and water from both Cloisite 30B and OP1311. Copyright © 2009 John Wiley & Sons, Ltd.