Phosphonitrilic chloride. XXVI. Synthesis of cyclophosphazene polymer by polycondensation reaction of tetrachlorodiphenyl triphosphazene and aromatic diamine compounds

Tetrachlorodiphenyl cyclotriphosphazene N₃P₃Cl₄(C₆H₅)₂ (TPC) has been synthesized by Friedel-Crafts reaction. The polycondensation of TPC with aromatic diamine compounds has been carried out in pyridine. The products obtained from the reaction of TPC with aromatic diamine compounds were slightly soluble in polar organic solvents. The molecular weights measured by the method of end group analysis were about 2800 to 10800. The products were amorphous, brown, yellow or white coloured solids. The softening points of all polycondensation products were found to be in the region of 100°C to 120°C. The electrical conductivity of the products obtained from TPC with p-phenylenediamine and p,p′-diaminodiphenyl sulfone was determined to 5 × 10¹² (Ωcm)^?1 and 1 × 10¹⁵ (Ωcm)^?1, respectively.     

New aspects of the synthesis of polymercaptals

The proton-catalyzed polycondensation of aromatic aldehydes with aliphatic and aromatic α,ω-dithiols leads to polymercaptals. The reaction may be carried out in bulk or solution. The bulk polycondensation was catalyzed by hexafluorophosphorous acid (HPF₆), formed photochemically by irradiation of the samples containing diaryliodonium salt. The polymers were obtained in high yields but with low molecular weights of M_n 2300–5700 determined by vapour pressure osmometry (VPO). High-molecular-weight products of M_n 9100–24000 (VPO) were obtained by solution polycondensation in dichloromethane catalyzed by p-toluenesulfonic acid. The polymers have been characterized by NMR, VPO, GPC and TGA. Cyclic side products have been isolated and identified. Polyrotaxane structures were found under special conditions.     

Linear polysulfonates. I. Products of 4,4′-(1-cyclothexylidene) diphenol and 4,4′-(2-norbolidene) diphenol with some aromatic disulfonyl chlorides

Aromatic (poly)cycloaliphatic polysulfonates of high molecular weight can be easily obtained by interfacial polycondensation of aromatic (poly)cycloaliphatic diphenols with aromatic disulfonyl chlorides. The polysulfonates were found to have a low degree of crystallinity, softening ranges in the region 180–310°C and molecular weights in the region: M?_n 3190–4420, and M?_w 19900–83370, thermal stability to above 300°C, and reduced viscosities in the range 0.2–1.00 dL/g.     

Condensation products from imidobis(sulfuryl chloride)

A study of model compounds and polycondensation products derived from imidobis(sulfuryl chloride) (IBSC), HN(SO₂Cl)₂, has been carried out and their structures determined. The model compounds were reaction products of IBSC with aniline or ethyl alcohol. Polymeric products were obtained by polycondensations with (1) p-phenylenediamine and (2) 2,2-bis(4'-hydroxyphenyl)-propane. The products were characterized by elemental analysis, infrared, NMR, DSC, TGA, and viscometry data.     

Die reaktion von diandiglycidyläther mit aromatischen diaminen

m-Phenylendiamine, p,p'-diaminodiphenylmethane and p,p'-diaminodiphenylsulphone were evaluated as hardeners for low molecular weight epoxide resins, and basic physical constants characterizing the kinetics of the reaction of diglycidylether of diane with the above hardeners were determined. Using the relation between viscosity, average molecular weight, and degree of reaction it was possible to characterize the existence range of the so-called epoxide-pregels which are formed from mixtures of epoxide resins with aromatic amines at lower temperatures. The applicability of SMITHS equation related to the kinetics of reaction between epoxidic compounds and amines was verified. The kinetic of reaction indicates the existence of hydrogen bonds at the epoxide groups, it may be assumed, however, that the presence of these relatively strong intermolecular bonds affects even the rate of pregelation.     

Preparation,modification, and characterization of pitches from apricot stones

Apricot stones steam pyrolysis tar and mixtures with petroleum pitch were modified by sulfuric acid and heat treatment at various temperatures for the purpose of obtaining a raw material for the production of carbon-related materials. The products obtained were characterized by elemental analysis, total carbon contents, FTIR spectroscopic analysis, ¹H and ¹³C NMR spectroscopic analyses, softening point measurement, and oxygen functional group content. During the acid and heat treatment, the reactions of polycondensation and polymerization occur. The heat-treatment modification of the pitches decreases the oxygen-containing groups and sulfur content and increases the content of aromatic structures. Chemical transformations and the removal of light components increase the softening point of the pitches. The results show that apricot stones tar with some additional modifications can be used as a raw material for the production of advanced carbon materials.     

The characterization of asphaltenes and preasphaltenes obtained under various coal liquefaction conditions

A CP-MAS ¹³C NMR study of asphaltenes and preasphaltenes obtained under various coal liquefaction conditions is reported. The carbon aromaticity, f_a, of the solid extracts from the reaction products has a close relation with the reaction conditions. By plotting f_a against the atomatic $\text{H}\text{C}$ ratio for these solid products on the characterization chart for model polycyclic aromatic compounds, the molecular structures with relation to the liquefaction pathway from coal to oil can be proposed.     

Hydrogenation of liddell vitrinite: Effects of metal halide catalysts in the temperature range 200–480°C

A vitrinite concentrate prepared from the Liddell Seam (high volatile bituminous coal, NSW, Australia) has been hydrogenated in an unstirred 50 cm³, batch autoclave at reaction temperatures between 200 and 480°C in the presence of metal halides (SnCl₁ or ZnCl₁) and/or alumina (α-Al₁O₃). A vehicle was not used. The influence of reaction temperature, metal halide and alumina on the composition of the products was studied by gas chromatography (GC), gel permeation chromatography (gpc), ¹H solution and ¹³C solid-state cross polarization (CP) nuclear magnetic resonance (nmr) spectroscopy and optical microscopy.The metal halides lower the temperature at which softening and agglomeration of vitrinite takes place. The resultant plastic isotropic material forms mesophase at temperatures above 400°C unless an inert diluent, i.e. alumina, is added. The alumina inhibits reactions involved in the formation of mesophase which would otherwise compete with hydrogenation reactions that yield hexane soluble material (oil).Above 400°C carbon monoxide, carbon dioxide and C₁-C₅ alkanes are the principal gaseous products. At lower temperatures, in the presence of alumina, ethylene is formed in the catalysed experiments; the ethylene is converted to ethane at higher temperatures. The structure of the hexane soluble products derived from vitrinite is also temperature dependent. Above 420°C much of the aliphatic component decomposes to yield further quantities of hydrocarbon gases. Tin(II) chloride and zinc chloride produce hexane soluble products of similar molecular composition, which suggests that they operate through a similar mechanism.The addition of alumina to the reaction mixture results in a more aromatic liquid product with shorter aliphatic carbon chains. Whether or not alumina is present, the aromaticity of the solid residues increases with increase in hydrogenation temperature. Thus the increased aromaticity of the liquid products is not caused by the extraction of a greater proportion of aromatic material from the coal with increase in the hydrogenation temperature. It follows that with increase in hydrogenation temperature an increasing proportion of the aliphatic material becomes transformed into aromatic compounds and/or gas.In summary, the results show that over a wide range of temperatures (200–480°C) the structure of the hexane soluble product depends on the thermal stability of the products and the degree of competition from reactions leading to mesophase formation, and not on the nature of the halide catalyst.     

Water soluble trehalose-derived oligoamides

A new family of oligotrehaluronamides was synthesized through the polycondensation of α,α-trehaluronic acid dimethyl ester and different diamines or polyamines. In particular, diamines with different molecular structure (1,n-alkylene diamines, aromatic diamine, and alkyleneoxydiamine) were used in order to modulate the molecular weights and the physical characteristics of the products, such as T_g, hydrophilic or hydrophobic properties, and solubility. α,α-Trehaluronic acid was obtained from a renewable source as α,α-trehalose. The syntheses of oligotrehaluronamides were carried out in different solvents such as ethanol, methanol, THF and DMSO, using triethylamine as catalyst. All the compounds obtained in this study were characterized through FT-IR and NMR spectroscopy. The molecular weights were evaluated by ¹H-NMR and in some cases compared with those obtained from ESI-MS spectrometry. Glass transition temperatures and melting points were detected by differential scanning calorimetry. Low molecular weight oligoamides, containing several hydroxyl groups, are water-soluble and could be used in water-based formulations.     

Synthesis and investigation of the properties of poly(phenyl‐α‐naphthylsilylene)–dimethylsilylene copolymers

A Wurtz‐type reductive coupling reaction of dichlorophenyl‐α‐naphthylsilane was carried out in a mixture of toluene and o‐xylene in the presence of sodium and a catalytic amount of mercury; α,ω‐dichlorophenyl‐α‐naphthylsilylenes of various degrees of polymerization were obtained. Through the hydrolysis of α,ω‐dichlorophenyl‐α‐naphthylsilylenes, corresponding dihydroxy compounds were obtained. The heterofunctional polycondensation of α,ω‐dihydroxyphenyl‐α‐naphthylsilylenes with α,ω‐dichlorodimethylsilylenes was performed both without amines and in the presence of amines. Heterofunctional polycondensation without amines did not proceed with the formation of high molecular weight compounds because the cleavage of both ? Si? Si? and ?Si? O? Si? bonds took place during condensation. In the presence of amines, polysilylene–silylene copolymers were obtained. The synthesized copolymers were investigated with gel permeation chromatography, differential scanning calorimetry, roentgenography, and thermogravimetry. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1047–1056, 2002     

IR Spectroscopy in the Solution of Many Problems in Continuous Synthesis of Poly-(p-Phenylenebenzobisthiazole)

The initial products for continuous polycondensation in fabrication of PPBT were investigated: polyphosphoric acid (PPA), P₂O₅, and 2,5-diamino-1,4-dimercaptobenzene diphosphate (DADMB). Criteria were found for assessing their properties that satisfy the requirements of synthesis. The spectral criteria of formation of the product of addition of PPA to DADMB in the initial stages of polycondensation were established and suggested a strong reaction between the components (on the level of a chemical reaction); the kinetics of the initial stages of synthesis of PPBT at different temperatures was investigated. The very pronounced extremal character of the kinetic curves describing the initial and subsequent stage of synthesis in spectral parameters suggests the formation of a product of addition at the extremal point and the appearance of several extrema on the kinetic curves indicates the discrete character of the addition process. The results of the kinetic studies of the initial stages of the polycondensation can be used in selecting the optimum temperature-time regime of conducting them.     

Studies on the formation of poly(ethylene terephthalate): 6. Catalytic activity of metal compounds in polycondensation of bis(2-hydroxyethyl) terephthalate

The rate parameters (p and d values) associated with the rate constants of propagation and thermal degradation reactions in the polycondensation process of bis(2-hydroxyethyl) terephthalate (BHET) in the presence of various metal compounds as catalysts at 283°C, calculated from the time dependence of the molecular weight of the formed polymer, were used to evaluate each metal compound in its catalytic activity. These logarithms of the p and d values were correlated by linear relationships (mountain-shaped) with the stability constants (log β₁) of dibenzoyl methane (DBM) complexes of the corresponding metal species. Consequently, the stability constant of DBM complex of each metal species was found to be very useful in forecasting the catalytic activity of the metal compound. The compound of metal species with values of log β₁ about 12 was most active as the catalyst on the propagation reaction and that of values about 11 was most active on the thermal degradation reaction.     

废PET改性二聚酸型PA及其应用

利用废弃对苯二甲酸乙二醇酯（PET）对国产二聚酸型聚酰胺（PA）进行改性,合成了满足热缩材料、电视机和汽车等领域使用要求的聚酰胺热熔胶。采用GPC、DSC、SEM等测试手段对产品进行表征,分析了合成过程,考察了影响产品性能的主要因素,并将所得产品与改性前PA及进口同类产品性能进行比较。结果表明：该反应主要由酯-酰胺交换、醇解和缩聚三步构成;共混时间延长,温度升高,酯-酰胺交换程度加深,产品软化点升高;PET加量增加,产品软化点提高,超过20%时,体系相容性变差,产品呈脆性;缩聚时间越长,产品黏度越大,软化点越高。     

Polyestereamide 6NT6: polycondensation kinetics,d.s.c. and n.m.r. studies of thermally treated samples

Samples of alternated polyestereamide (PEA) obtained after prolonged polycondensation were examined viscometrically and by differential scanning calorimetry. The intrinsic viscosities at different polycondensation times for various process parameters were determined. A phenomenological equation is proposed and used to determine the polycondensation and degradation kinetic parameters. D.s.c. of samples at different polycondensation times suggests that an extensive rearrangement of the alternated polymer takes place, leading to the formation of products having higher and lower melting points. Evidence and quantitative evaluation of these phenomena were obtained by means of ¹H and ¹³C n.m.r. studies on samples purposely treated above their melting point. An interpretation based on an interchange reaction between ester and amide linkages is given.     

Novel poly(azomethine-urethane)s and their polyphenol derivatives derived from aliphatic diisocyanate compound: Synthesis and thermal characterization

Until now, only a few kinds of poly(azomethine-urethane)s (PAMUs) including aromatic hydroxy benzaldehyde and aminophenol compounds were obtained and studied with thermal degradation steps. However, oligo/polyphenol-based PAMUs have not been synthesized yet. In this study, some kinds of this class of PAMUs were synthesized in three steps. At the first step polyurethane (PU) was synthesized by the copolymerization reaction of 2,4-dihydroxybenzaldehyde with hexamethylene diisocyanate (HDI) under argon atmosphere. At the second step, the poly(azomethine-urethane)s (PAMUs) were obtained by graft copolymerization of the preformed PU with aminophenols (2-aminophenol, 3-aminophenol, and 4-aminophenol). At the last step the obtained PAMUs were converted to the polyphenol derivatives via oxidative polycondensation reaction (OP). The structures of the obtained compounds were confirmed by FTIR, UV-vis, ¹H-NMR, and ¹³C-NMR techniques. The number-average molecular weight (M_n), weight average molecular weight (M_w) and polydispersity index (PDI) values of the synthesized compounds were determined by the size exclusion chromatography (SEC). The synthesized compounds were also characterized by solubility tests, TG-DTA, and DSC. Fluorescence measurements were carried out in various concentrated DMF solutions to determine the optimum concentrations to obtain the maximal PL intensities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

High-resolution mass spectrometric investigation of heteroatom species in coal-carbonization products

High-resolution mass spectrometry is being used to determine the organic species present in coal-carbonization products, airborne particulates, and municipal effluents. Qualitative analysis of an 80–85 °C softening point pitch yielded molecular formulae for 239 compounds which correspond to a minimum of 108 structural types and their alkyl derivatives. Of these, 76 structural types are composed of 8 different combinations of elements; structures containing CH, CHO, and CHN are most numerous while species containing S, N₂, ON, O₂, and O₂N₂ are also present.     

废弃PET聚酯/二聚酸聚酰胺共聚物的合成及过程分析

以010树脂、废弃PET聚酯和二元醇为主要原料,合成了满足国家通信行业标准要求的电缆热缩套管用聚酰胺热熔胶。采用FTIR、DSC、SEM等测试手段跟踪反应过程,对产物进行表征,推测了反应机理,研究了产品主要性能的影响因素。结果表明:主要反应为酯-酰胺交换、醇解和缩聚反应;共混时间越长,酯-酰胺交换程度越深,产品的软化点越高;醇的加量越多或缩聚时间越长,产品的黏度越大。     

Microwave-assisted polymerization process: A way to design new, high molecular weight poly(arylimidazole)s

In this paper, the microwave-assisted synthesis of high molecular weight poly(arylimidazole)s is described. These polymers were obtained by a one-pot polycondensation reaction involving a bis(α-diketone), an aromatic dialdehyde and ammonium acetate. Depending on the dialdehyde monomer, different poly(arylimidazole)s structures were synthesized. Structural characterization (¹H and ¹³C NMR), thermal properties (T_g, thermal stability) as well as a molecular weight determination of the polymers are reported.     

Polyesters containing sulfur. I. Products of melt polycondensation of diphenylmethane-4,4′-di(methylthioacetic acid) with some diols

Several new polyesters containing sulfur in the main chain were obtained by melt polycondensation of diphenylmethane-4,4′-di(methylthioacetic acid) with ethanediol, 1,3-propane diol, 1,4-butanediol, 1,5-pentenediol, 1,6-hexanediol, 1,2-propanediol, and 2,2′-oxydiethanol. The structure of all polyesters was determined from elemental analysis and infrared (IR) spectra. Yield, reduced viscosity, molecular weight, and softening temperature for reaction products have been found. Initial decomposition and initial intensive decomposition temperature were defined from the curves of thermogravimetric analysis.     

Synthesis and thermal,optical and morphological characterization of oligomeric polyamides based on thiophene and alkyl/phenyl‐silane moieties. Study of the electrospun deposition process

Polyamides were synthesized from a thiophene‐containing diamine by direct polycondensation with organosilane acyl dichlorides. The obtained polymers had good solubility in common organic solvents and THF, with TDT_10% values upper than 400 °C and T_g between 150 and 180 °C. Combination of these properties reveals that the processability of the polymers was increased with respect to traditional aromatic polyamides. Inherent viscosity values and SEC analysis indicated low molecular weight species. Samples showed high visible transparency and bandgap values associated to insulating materials. Polymer solutions were deposited using electrospun technique and their surface properties were studied by SEM. Spheres were created according to electric field applied during deposition process. Low molecular weight and conductivity prevent charge accumulation in the surface hindering fibers generation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43702.