New polymer syntheses: XV. Synthesis and characterization of new polyketoamine polymers containing ether or thioether linkages in the main chain

An interesting new class of linear polyketoamine polymers containing ether or thioether linkages in the main chain has been synthesized by solution polycondensation of 4,4′‐bis(chloroacetyl)diphenyl ether ( I ), 4,4′‐bis(chloroacetyl)diphenyl sulfide ( II ) and 4,4′‐bis(chloroacetyl)diphenyl sulfone ( III ) with various aliphatic and aromatic diamines. The model compounds IV, V and VI were synthesized from the monomers I, II and III with aniline in dry benzene and their structures were confirmed by elemental and spectral analyses. The resulting polymers were characterized by elemental and spectral analyses, as well as by solubility and viscometry measurements. The thermal properties were evaluated by TGA and DSC and correlated to their structural units. X‐ray analysis showed that the polymers had some degree of crystallinity in the region 2θ = 5° to 60°. The UV‐visible spectra of some selected polymers were measured in dimethylsulfoxide (DMSO) solution and showed absorption bands in the range 260–475 nm, due to n–π* and π–π* transition. In addition, the morphological properties of selected examples were tested by SEM, and the electrical properties of these polymers were measured. Copyright © 2005 Society of Chemical Industry     

Salts of Tetrazolone – Synthesis and Properties of Insensitive Energetic Materials

Tetrazolone (5‐oxotetrazole, 1 ) is formed by diazotization of 5‐aminotetrazole in the presence of CuSO₄. Nitrogen‐rich salts such as guanidinium ( 2 ), 1‐aminoguanidinium ( 3 ), 1,3‐diamino‐guanidinium ( 4 ), 1,3,5‐triamino‐guanidinium ( 5 ), ammonium ( 6 ), hydrazinium ( 7 ) and the hydroxylammonium ( 8 ) salts of tetrazolone were prepared by facile deprotonation or metathesis reactions. All compounds were characterized by single‐crystal X‐ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis and DSC measurements. The heats of formation of 2–8 were calculated using the atomization method based on CBS‐4M enthalpies. With these values and the experimental (X‐ray) densities several detonation parameters such as the detonation pressure, velocity, energy and temperature were computed using the EXPLO5 code (V.5.04). In addition, the sensitivities towards impact, friction and electrical discharge were tested using the BAM drop hammer and friction tester as well as a small scale electrical discharge device.     

Synergistic effect in gamma-irradiated poly(vinyl chloride) hard foils stabilized by plasticizer–stabilizer systems

Changes in transparency and color as well as G_HCl values of hard PVC foils exposed to gamma radiation were investigated while using different amounts of the stabilizers ethylene glycol bis-β-aminocrotonate (I), calcium/zinc laurate + epoxy compounds (II), and magnesium/zinc stearate + sorbitol + epoxy compounds (III), and plasticizers dioctyl phthalate (DOP) (IV), dioctyl sebacate (V), propylene glycol polyadipate + octyl alcohol composition (VI), and diisotridecyl phthalate (VII). A strong synergistic effect was observed in systems containing both plasticizer and stabilizer. Best results were obtained for the I + II + IV, I + II + V, and I + III + V systems.     

Studies on Energetic Salts Based on (2,4,6‐Trinitrophenyl)guanidine

(2,4,6‐Trinitrophenyl)guanidine was synthesized and its thermal and energetic properties were investigated. The reaction of (2,4,6‐trinitrophenyl)guanidine with different acids, such as nitric, picric, perchloric, and hydrochloric acid results in protonation of (2,4,6‐trinitrophenyl)guanidine and the formation of the corresponding salts (cation : anion ratio 1 : 1). The reactions are performed at ambient temperature in H₂O or EtOH and produce qualitatively pure products with energetic properties, which are typical of those of secondary explosives. The compounds were characterized using multinuclear NMR spectroscopy, IR and Raman spectroscopy, as well as mass spectrometry. Single crystal X‐ray diffraction studies were performed and the structures of the four different salts at low temperatures were determined. The thermal stabilities were measured using differential scanning calorimetry (DSC). The sensitivities were determined using the BAM drophammer and friction tests. The heats of formation were calculated by the atomization method based on CBS‐4M enthalpies. Using these values as well as the X‐ray or pycnometric densities, several detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code.     

Studies on cyanine dyes. IV. Synthesis of new styryl oxa-cyanine dyes

The condensation reaction of benzoxazole-2-carboxaldehyde (I) with quaternary salts of heterocyclic compounds, in the presence of piperidine as a catalyst, afforded styryl cyanines (II). Interaction of (I) with the non-quaternised heterocyclic compounds at a longer time gave the corresponding dimethine bases (III). On the other hand, benzoxazole-2-carboxaldehyde-3-ethiodide (IV) interacted with quaternised and non-quaternised heterocyclic compounds achieved styryl cyanines of the type (V) and (VI), respectively. Absorption spectra for these compounds in EtOH are discussed.     

Functionalization of Fluorinated Benzenesulfonamides and Their Inhibitory Properties toward Carbonic Anhydrases

Substituted tri‐ and tetrafluorobenzenesulfonamides were designed, synthesized, and evaluated as high‐affinity and isoform‐selective carbonic anhydrase (CA) inhibitors. Their binding affinities for recombinant human CA I, II, VA, VI, VII, XII, and XIII catalytic domains were determined by fluorescent thermal shift assay, isothermal titration calorimetry, and a stopped‐flow CO₂ hydration assay. Variation of the substituents at the 2‐, 3‐, and 4‐positions yielded compounds with a broad range of binding affinities and isoform selectivities. Several 2,4‐substituted‐3,5,6‐trifluorobenzenesulfonamides were effective CA XIII inhibitors with high selectivity over off‐target CA I and CA II. 3,4‐Disubstituted‐2,5,6‐trifluorobenzenesulfonamides bound CAs with higher affinity than 2,4‐disubstituted‐3,5,6‐trifluorobenzenesulfonamides. Many such fluorinated benzenesulfonamides were found to be nanomolar inhibitors of CA II, CA VII, tumor‐associated CA IX and CA XII, and CA XIII. X‐ray crystal structures of inhibitors bound in the active sites of several CA isoforms provide structure–activity relationship information for inhibitor binding affinities and selectivity.     

Thermodynamic stability of SFCA (silico‐ferrite of calcium and aluminum) and SFCA‐I phases

Silico‐ferrite of calcium and aluminum (SFCA) and SFCA‐I phases form in iron ore sintering operations. Their behavior in blast furnaces, with sinter being a significant component of blast furnace burden, is of critical importance to the ironmaking process. They have complex disordered crystal structures and form over a range of composition. In the present work, enthalpies of formation from oxides for five different SFCA compounds and one SFCA‐I phase were measured by oxide melt solution calorimetry in molten lead borate solvent at 800°C. The enthalpies of formation from binary oxides are zero within experimental error for SFCA phases and slightly endothermic for SFCA‐I, confirming that SFCA phases are stabilized, not by energetics, but by their configurational entropies resulting from atomic site disorder. In addition, enthalpies of drop solution into a molten slag at 1450°C were measured for SFCA phases and show good agreement with values predicted using the heats of formation and previously measured drop solution enthalpies for the binary oxides. This agreement confirms data consistency and shows that the presence of variable amounts of SFCA relative to binary oxides in a sinter will have negligible effect on the heat balance in the blast furnace.     

Synthesis and antibacterial activity of some new diarylsulphides and diarylsulphones containing azetidin-2-one and/or diazetidin-2-onyl moities

Cyclonucleophilic addition of N-phthaloylaminoacid chlorides (II on 4-(N-ary-lideneamino)-4′-nitrodiphenyl sulphides (I) in dioxane and triethylamine afforded 4-(4″-aryl-3″-phthalylamino-2″-oxo-azetidin-1″-yl)-4′-nitro-diphenyl sulphides (III). Hydrazinolysis of III yielded 4-(4″-aryl-3″-amino-2″-oxo-azetidin-1″-yl)-4′-nitro-diphenyl sulphide hydrochlorides (IV). Condensation of IV with anisaldehyde using ethanol and piperidine as a basic catalyst gave 4-(4″-aryl-3″-anisylidine amino-2″-oxoazetidin-1″-yl)-4′-nitrodiphenylsulphides (V) in good yields. Interaction of V with chloroacetyl chloride in dioxane and triethylamine produced 4-(4″-aryl-3″-substituted β-lactamyl-2″-oxo-azetidin-1″-yi)-4′-nitrodiphenyl sulphides VI. Oxidation of IV, V and VI using hydrogen peroxide/glacial acetic acid mixtures gave the corresponding sulphones (VII), (VIII) and (IX). Sulphones of the type IX were obtained by unequivocal synthesis through interaction of sulphone-anils VIII with chloroacetyl chloride. The antibacterial activities of some of these compounds were determined.     

Anti-adhesive effects of Budesonide combined with spraygel in a cecal abrasion model: an experimental study

Many methods have been described for preventing or reducing postoperative adhesions. In this work, we evaluated the effectiveness of Budesonide in combination with SprayGel in a reducing postoperative adhesion in rats as the model. Cecal abrasion was achieved in 60 male Sprague-Dawley rats, by brushing and by applying 70% alcohol. The rats were separated into six groups and treated with six solutions (Group I – saline; II – Budesonide 50?μg; III – Budesonide 250?μg; IV – SprayGel; V and VI – SprayGel?+?Budesonide 50 and 250?μg). Serum Budesonide, glucose, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and blood urea nitrogen levels were measured at postoperative day (POD) 2 and 14. The rats were killed on POD 14, and intra-abdominal adhesion formation was scored. Histopathological samples were obtained from the cecum and terminal ileum to evaluate microscopic adhesion formation. Our results showed that Group VI had both the minimum macroscopic adhesion score and the minimum microscopic score. All other groups had significantly lower microscopic adhesion scores than Group I. However, there was no statistical significance among any other groups. Serum AST levels of Group III were significantly higher than in Groups I, II, IV, and V (p?<?0.046). Serum AST levels of Group III on POD 14 were also significantly higher than that of all other groups (p?<?0.02). On POD 14, there was no Budesonide in the sera of Groups II and V. However, Groups III and VI had trace amounts of Budesonide (0.009 and 0.007?μg, respectively). In conclusion, we have showed that the effect of Budesonide is dosedependent. Both anti-adhesive and hepatotoxic side effects of Budesonide increased as the dose increased. Combining Budesonide with SprayGel synergistically increased the anti-adhesive benefits and prevented hepatotoxicity from the slower release of Budesonide.     

Addition of phthalimidonitrene to acetylenic fatty acid esters: Synthesis of long-chain 2-phthalimido-2H-azirines

Lead tetraacetate (LTA) oxidations of N-aminophthalimide in the presence of acetylenic fatty acid esters have resulted in the formation of corresponding 1H-azirines that spontaneously rearranged to give 2H-azirines in moderate yields. 2H-Azirine derivatives (IV, V and VI) of acetylenic fatty acid esters, methyl 10-undecynoate (I), methyl 9-undecynoate (II) and methyl 9-octadecynoate (III), respectively, have been prepared and characterized with the help of spectral and micro analyses.     

Crystal Structure and Improved Synthesis of 1‐(2H‐Tetrazol‐5‐yl)guanidium Nitrate

Energetic derivatives of tetrazoles are one of the key areas of research focus in pursuit of novel high energy materials, useful as propellants and explosives. Herein, the crystal structure and an improved synthetic procedure of 1‐(2H‐tetrazol‐5‐yl)guanidine ( 1 ) and its nitrate salt ( 2 ) are reported. The compounds were structurally characterized by spectroscopic (FT‐IR, ¹H NMR, ¹³C NMR) and elemental analysis. The molecular structure of tetrazolyl guanidium nitrate ( 2 ) was solved using low temperature single‐crystal X‐ray diffraction. 2 crystallized as its hemihydrate in the orthorhombic space group Fdd2, with a crystal density of 1.69 g cm⁻³. Thermal behavior and decomposition of the molecules were studied with differential scanning calorimetry (DSC). Molar enthalpy of formation (Δ_fH^m) of compound 2 was back calculated from heat of combustion (Δ_cH⁰) value obtained experimentally using bomb calorimetric measurements. Lattice enthalpy of 1‐(2H‐tetrazol‐5‐yl)guanidium nitrate was directly calculated from measured crystal density using Jenkins equation. Preliminary ballistic parameters of the compound were predicted and compared with reported high nitrogen tetrazole derivatives.     

Structure and processability of iodinated poly(vinyl alcohol) (III)‐structure of films iodinated in solution before casting

Films iodinated at solution before casting (IBC films) were prepared by casting aqueous solutions of 10 wt % poly(vinyl alcohol) (PVA) containing selected quantities of I₂/KI. The quantity of I₂/KI was controlled to obtain 15.2, 39.8, 83.2, 117.0, and 140.1%. The Thermogravimetry (TG) curves of the IBC film exhibited three distinct zones corresponding to the evaporation of H₂O and I₂ molecules (zone I), evaporation of I₂ and partial decomposition of side groups (? OH) (zone II), degradation of the remaining side groups and partial degradation of the main chain (zone III‐1), and degradation of the remaining main chain and the char zone corresponding to KI. The crystalline structure of the film with a weight gain of 15.2% was almost the same as that of the pure PVA, and the film with the weight gain of 140% was almost amorphous. The differential scanning calorimetry (DSC) thermograms of the IBC films with a weight gain of 15.2% and 39.8% indicated endothermic single or double peaks at around 180°C, corresponding to the crystal melting and degradation of side groups; those with weight gains of 83.2% and above indicated exothermic peaks at around 170°C, corresponding to crystallization, and broad endothermic peak at around 180–200°C, corresponding to the crystal melting and degradation of side groups. The dynamic mechanical α_a transition of the IBC film with the weight gain of 140.1% appeared at around 20°C. X‐ray diffraction and DSC analysis of deiodinated films show that the crystal structure, on deiodination of all the IBC films, regardless of crystallinity, returned to that of the pure PVA. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3497–3502, 2006     

Antioxidants and stabilizers. XXXV. On the character of discolouring compounds formed from 2,2′-methylene-bis-(4-methyl-6-tert.-butylphenol) during oxidative degradation of polymers

A model reaction of 2,2′-methylene-bis-(4-methyl-6-tert.-butylphenol) (I) with tert.-butylhydroperoxide in the presence of cobalt-II-acetylacetonate yielded coloured products which cause the discolouration of substrates stabilized with antioxidant I. Dimer V, trimer VI and tetramer VIII were identified, and their relation to the colourless oligomeric products II and III was proved. The structure of dimer V was confirmed by an independent synthesis. The formation of analogous compounds was proved by an investigation of the oxidation of tetralin; it is discussed in connection with the oxidation of isotactic polypropylene. Both materials were stabilized with antioxidant I.     

Synthesis and characterization of new water‐soluble metal–polymer complex and its application for arsenite retention

New water‐soluble metal–polymers of poly(acrylic acid)s (AA) with different amounts of tin (3, 5, 10, and 20 wt %) were synthesized and characterized. The materials were characterized by ¹H NMR and FTIR spectroscopy, X‐ray diffraction (XRD), specific area by isotherm of CO₂, and thermogravimetry‐differential scanning calorimetry (TG‐DSC). The synthesized material is crystalline and shows an average crystal size 90–130 nm and has a high thermal stability (>200°C). Texturally, they are complexes of small specific area, which decreases when the crystal size increases with the tin content. Presumably, the Sn(II) ions coordinate through 2‐4 carboxylate groups by a conventionally bidentate structure; however, they are not symmetric. Studies have been dedicated to support of tin in polymers to increase its efficiency in eliminating pollutants. The tin‐metal salt is added to the poly(AA) matrix to increase its ability to remove As(III) from an aqueous solution. The liquid‐phase polymer‐based retention technique is applied to retain and separate contaminants from water. The analysis of As(III) and As(V) species was made by combining liquid high‐resolution chromatographic coupled to hydride generation absorption atomic spectrophotometer (HPLC‐HG‐AAS). All indicated that As(III) was the predominant species bound to the polymer complex for the pH range 4–8. The polymers containing 10 and 20 wt % Sn presented the highest retention of 70 and 90% As(III), respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Deduction of a facile method to construct Antheraea mylitta silk fibroin/gelatin blend films for prospective biomedical applications

Blend films of two types (I and II) were prepared by mixing Antheraea mylitta silk fibroin (AMF) and gelatin solution in various blend ratios via the solution casting method. Two different crosslinkers, namely glutaraldehyde and genipin, were used during blend preparation. The structural characteristics and thermal properties of the blend films were examined by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), Thermogravimetric analysis (TGA) and Diffrential scanning calorimetery (DSC). The FTIR spectra showed conformational alterations in type I blend films while type II films attained high β‐sheet crystallinity. The XRD diffractograms presented a high degree of crystallinity in type II blend films compared to type I, which showed an almost amorphous structure. Further, thermal and biological studies were conducted on type II films. According to the TGA thermograms, the degradation temperature of the crosslinked blend films shifted compared to pure gelatin and pure AMF films. Partial miscibility of the two components was indicated by DSC thermograms of the blends. The high water uptake capacity of type II blend films was found to imitate hydrogel behaviour. The blend films did not show any toxicity in 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide (MTT) assay and supported L929 fibroblast cell spreading and proliferation. The biodegradation of the blend films was significantly faster than the pure silk film. © 2020 Society of Industrial Chemistry     

Chemistry of Uranium in Glass-Forming Melts: Redox Interactions of Uranium with Chromium and Iron in Aluminosilicates

The mutual interactions by internal redox reactions of uranium and chromium and uranium and iron in two aluminosilicate glass-forming melts were studied by optical spectrophotometry. Cr(VI) was found to oxidize completely all available U(V) and U(IV) to U(VI), whereas Fe(III) was not a strong enough oxidizing agent to affect the uranium redox states. Cr(II) totally reduced all the U(V) and U(VI) in the system to U(IV); Fe(II) did not reduce any of the uranium redox species. Cr(III) coexisted with U(VI), U(V), and U(IV) in the melts. The degree of mutual interaction was governed not only by the difference in redox potentials between the respective redox couples, but also by the stability of molecular associations between the redox ions within the melt microstructure.     

Preparation and characterization of derivatives of isoricinoleic acid and their antimicrobial activity

Methylisoricinoleate (methyl-9-hydroxy-cis-12-octadecenoate) (I) has been derivatized to yield new fatty acid derivatives analogous to those obtained from the ricinoleic acid of castor oil. These derivatives include 1,9-dihydroxy-12-octadecene (II); 1,9-diacetoxy-12-octadecene (III); 12,13-epoxy-1,9-diacetoxyoctadecane (IV); 9-cyanoethoxy-1-hydroxy-12-octadecene (V); 1-morpholine-9-hydroxy-12-octadecene (VI), and 1-morpholine-9-cyanoethoxy-12-octadecene (VII). Structures of these compounds were established by chemical and spectral data. The compounds V, VI and VII showed antifungal activity againstAlternaria sp.,Helminthosporium sp.,Penicillium citrinum, Fusarium oxysporum, Aspergillus ochraceous, A. flavus, A. niger, Actinomyces sp. andCladosporium harbarum.     

手性烯唑醇为活性组分的杀菌聚合物的合成

以杀菌剂烯唑醇（Ⅰ）为底物,（-）-孟氧基乙酸为拆分试剂进行手性拆分,得到具有高杀菌活性的（R）-（E）-1-（2,4-二氯苯基）-2-（1,2,4-三唑-1-基）-4,4-二甲基-1-戊烯-3-醇（Ⅱ）。Ⅱ与丙烯酰氯反应生成了具有生物活性的可聚合单体（R）-（E）-1-（2,4-二氯苯基）-2-（1,2,4-三唑-1-基）-4,4-二甲基-1-戊烯-3-醇丙烯酸酯（Ⅲ）,Ⅲ经自聚或与丙烯酸或甲基丙烯酸甲酯共聚制得了杀菌聚合物（Ⅳ,Ⅴ,Ⅵ）,并进行聚合物活性组分的水解释放实验。总体上,在碱性介质中聚合物的活性组分水解释放速率大于在中性或弱酸性介质中的。Ⅳ和Ⅵ活性组分水解释放速率很低,而聚合物Ⅴ,随时间的延长,有大量的活性组分释出,初始释出质量浓度也较高,符合农用杀菌剂的速效性和持效性的要求,有实用意义。     

The conformational changes,crystal structure and melting behavior of poly(ethylene/ trimethylene terephthalate) copolyesters

The conformational changes, crystal structure and melting behavior of poly(ethylene/trimethylene terephthalate) (ET) copolyesters were investigated using in situ Fourier transform infrared (FTIR) spectroscopy, wide‐angle X‐ray diffraction (WAXD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) under isothermal crystallization conditions. The results show that the minimum melting temperature was observed in ET53, in which the relative amount of ethylene glycol (EG) to 1,3‐propanediol (PDO) was 52.68/47.32 and the PDO‐dimethyl terephthalate (DMT)‐PDO segments in the molecular chain dominated the crystal formation. The minimum crystallinity of ET copolyesters was found in ET66, in which the relative amount of EG/PDO was 65.91/34.09 and the EG‐DMT‐EG segments in the molecular chain dominated the crystal formation. A rapid and continuous conformational transition in ET copolyesters was observed using in situ FTIR in the first 10 min under isothermal crystallization conditions. The continuously adjusting conformation in the molecules reflects the crystallization of ET copolyesters. Based on the DSC and the X‐ray analyses of the crystallization behavior in the ET copolyesters, crystalline conformation transitions of molecules in ET copolyesters take place rapidly and early. Copyright © 2012 Society of Chemical Industry     

Copolyester of trimellitic acid,glycerol, and poly(ethylene glycol): Synthesis and characterization

A series of copolyesters having a broad range of biodegradable crosslinks were synthesised by FeCl₃‐catalyzed polyesterification of trimellitic acid and glycerol containing a small mol percent of poly(ethylene glycol) (PEG) of varied molecular weights. The polymer samples designated as I (1.5% PEG 2000), II (4.5% PEG 2000), III (7.5% PEG 2000), IV (1.5% PEG 4000), V (4.5% PEG 4000), VI (7.5% PEG 4000), VII (1.5% PEG 6000), VIII (4.5% PEG 6000), and IX (without PEG) are insoluble and moderately tough‐to‐elastic solids and were characterized by their swelling values in ethanol, glass transition temperatures (T_g), IR spectra, and X‐ray diffractograms. Sample IX (0% PEG) has the lowest equilibrium swelling (12% at 25°C) and the highest T_g (155°C) and, therefore, the highest crosslink density. The swelling increases and the T_g decreases as the PEG content or PEG molecular weight in a glycerol–PEG combination increases, indicating a corresponding decrease in the crosslink density of the polymers. Further, the equilibrium swelling value increases with increasing temperature. The IR spectra of the polymers indicate the formation of ester bonds at the expense of COOH and OH groups. The X‐ray diffractograms show their semicrystalline nature. The percent crystallinity values of 53, 52, 49, and 46 for II, III, V, and VII, respectively, and 54 for IX showed that the percent crystallinity decreases with an increasing PEG content and molecular weight in the same way as do the T_g values. Thus, higher T_g values are associated with a higher percent crystallinity, that is, with structures of higher order. The synthesized polymer samples with varied crosslink (biodegradable) densities are expected to be very suitable as matrices for controlled drug delivery over a varied period of time. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 343–346, 2004