Synthesis,thermal, and dynamic mechanical properties of 1,3‐bis(diphenylsilyl)‐2,2,4,4‐tetraphenylcyclodisilazane‐containing polydimethylsiloxanes

New and effective approaches to the synthesis of 1,3‐bis(diphenylsilyl)‐2,2,4,4‐tetraphenylcyclodisilazane‐containing polydimethylsiloxanes ( P1 and P2 ) were developed. P1 was obtained by polycondensation of cyclodisilazane lithium salt and chloroterminated polydimethylsiloxane. P2 was produced by hydrosilylation of vinyl‐terminated cyclodisilazane and hydrogen‐terminated polydimethylsiloxane. The polycondensation completed quickly at room temperature, while the hydrosilylation was facile and did not require cumbersome air‐sensitive operations. P1 and P2 were characterized by Fourier transform infrared, nuclear magnetic resonance, gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis (TGA), and isothermal gravimetric analysis (IGA). TGA revealed the outstanding thermal properties of P1 and P2 with 5% weight loss temperatures (T_d5) higher than 450°C. IGA proved their better thermal stability at 450°C for 800 min, compared to polydimethyldiphenylsiloxane. Dynamic mechanical analysis showed that silicone rubbers made from cyclodisilazane‐containing polydimethylsiloxanes could have a maximum tan δ value as high as 1.13 and had good prospects for damping material applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis,characterization, and thermal properties of alternate copolymers containing N,N′‐bis(diphenylsilyl)tetraphenylcyclodisilazane

Hexamethyldisilazane was used as the starting material to synthesize N,N′‐bis(hydroxydiphenylsilanyl)tetraphenylcyclodisilazane (BHPTPC). By condensation polymerization of BHPTPC with α,ω‐bis(dialkylamino)dimethylsiloxane, a series of alternate copolymers containing N,N′‐bis(diphenylsilyl)tetraphenylcyclodisilazane was synthesized. GPC studies show that the highest molecular weight was obtained at a ratio of 1.005 : 1 (BHPTPC: α,ω‐bis(dimethyl amino)dimethylsiloxane). Data of DSC indicate that the temperature of glass transition (T_g) and temperature of melting point (T_m) decreased with the increasing of dimethylsiloxane segments units. Three stages of degradation were found in the thermogravimetric analysis curves. The activation energy of the copolymer (with m = 2, 3, and 7) was calculated by using Flynn–Wall–Ozawa method. The activation energy of the copolymer with m = 2, 3, and 7 at second stage is 214, 211, and 184 kJ/mol, respectively. Isothermal gravimetric analysis shows that for the same temperature and the same time, the weight loss of the alternate copolymer was greatly less than that of common polydimethylsiloxane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 611–617, 2007     

Synthesis and characterization of polyamideimide‐branched siloxane and its gas‐separation

Polyamideimide‐branched siloxanes (PAIBrSs) were synthesized from 4, 4′‐(hexafluoroisopropyllidene)diphthalic anhydride (6FDA), p,p′‐oxydianiline (ODA), and aminopropyl‐terminated oligomeric dimethylsiloxane (ODMS). In this investigation, a mixture of N‐methylpyrrolidinone (NMP) and tetrahydrofuran (THF) was used as a cosolvent for the homogeneous mixing of poly(amic acid) (PA) and the ODMS solution. Thionyl chloride (SOCl₂) was used for the acylation of PA to activate the reaction between PA and ODMS. FTIR spectra showed an increase in the intensity of characteristic absorption peaks of dimethylsiloxane units with the amount of ODMS reacted. From thermogravimetric analysis (TGA), PAIBrSs showed good thermal stability, but relatively low thermal stability when compared with that of block poly(imide siloxane) (PIBlS) or poly(amideimide siloxane) (PAIBlS). A solubility test showed that dipolar aprotic solvents were relatively good solvents for the polymer. Gas separation was performed by single gas‐permeation equipment. The permeabilities of PAIBrS membranes are higher than those of PIBlS membranes and the selectivities of PAIBrS membranes are lower than those of PIBlS membranes. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 965–973, 1999     

Synthesis,characterization, and applications of novel additives of polysiloxane containing N,N′‐bis(diphenylsilyl)tetraphenylcyclodisilazane

Three N,N′‐bis(diphenylsilyl)tetraphenylcyclodisilazane‐based derivatives, N,N′‐bis(3,3,3‐trimethyl‐1,1‐diphenyl‐disiloxanyl)tetraphenylcyclodisilazane, N‐(3,3‐dimethyl‐1,1‐diphenyl‐3‐vinyl‐disiloxanyl)‐N′‐(3,3,3‐trimethyl‐1,1‐diphenyl‐disiloxanyl)‐tetraphenylcyclodisilazane, and N,N′‐bis‐(3,3‐dimethyl‐1,1‐diphenyl‐3‐vinyl‐disiloxanyl) tetraphenylcyclodisilazane, were synthesized. These compounds were synthesized in an easy and effective route. X‐ray single‐crystal diffraction analyses showed that the four‐member rings were planar rings, and the structures are different with the different substitution. The compound N,N′‐bis‐(3,3‐dimethyl‐1,1‐diphenyl‐3‐vinyl‐disiloxanyl) tetraphenylcyclodisilazane was added to the silicone rubber as additive to enhance the thermal stability greatly increased the thermal stability of the silicone rubber, without altering the glass transition temperature. The weight loss at 350°C in nitrogen atmosphere for 24 h reduced from 55.8% for 0 wt % to 9.8% for 10 wt % addition N,N′‐Bis‐(3,3‐dimethyl‐1,1‐diphenyl‐3‐vinyl‐disiloxanyl)tetraphenylcyclodisilazane. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Synthesis and properties of polysiloxane containing N,N′-bis(diphenylsilyl)tetraphenylcyclodisilazane

A new kind of polysiloxane containing N,N′-bis(diphenylsilyl)tetraphenylcyclodisilazane was prepared by the anionic polymerization with a “seed solution” as initiator. The synthesis of monomers N,N′-bis(hydroxydiphenylsilyl)tetraphenylcyclodisilazane (BHPTPC), N,N′-bis(chlorodiphenylsilyl)tetraphenylcyclodisilazane (BCPTPC), and 1,3-dichloro-1,1,3,3-tetraphenyldisilazane (DCTPS) are all reported in this study. The synthesized polysiloxane containing N,N′-bis(diphenylsilyl)tetraphenylcyclodisilazane was characterized by ¹H–NMR, ²⁹Si–NMR, gel permeation chromatography (GPC), and intrinsic viscosity. The thermal stability of the polysiloxane was studied by isothermal gravimetric analysis (IGA). The results demonstrated that the synthesized polysiloxane containing N,N′-bis(diphenylsilyl)tetraphenylcyclodisilazane had excellent thermal stability. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 929–933, 2001     

Viscosity/molecular‐weight relationship for γ‐(2,3‐dihydroxypropoxy)propyl‐terminated poly(dimethylsiloxane)s

A series of γ‐(2,3‐dihydroxypropoxy)propyl‐terminated poly(dimethylsiloxane) (DHT‐PDMS) samples with different molecular weights were prepared through the acid‐catalyzed equilibrium copolymerization of octamethylcyclotetrasiloxane and 1,3‐bis[γ‐(2,3‐dihydroxypropoxy)propyl]tetramethyldisiloxane. The intrinsic viscosity in toluene ([η]_toluene) and the number‐average molecular weight (M_n) were determined with an Ubbelohde viscometer and ¹H‐NMR spectra, respectively. In this way, the relationship between [η]_toluene and M_n was established. For 2.0 × 10⁴ < M_n < 4.0 × 10⁴, [η]_{toluene,25°C} was 1.874M_n ^0.323. The solution behavior of DHT‐PDMS was also investigated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1759–1762, 2004     

Thermal decomposition studies of Schiff‐base‐substitute polyphenol–metal complexes

The thermal behaviors of 2,3‐bis[(2‐hydroxyphenyl)methylene] diaminopyridine, oligo‐2,3‐bis[(2‐hydroxyphenyl)methylene] diaminopyridine, and some oligo‐2,3‐bis[(2‐hydroxyphenyl) methylene] diaminopyridine–metal complexes were studied in a nitrogen atmosphere with thermogravimetric analysis, derivative thermogravimetric analysis, and differential thermal analysis techniques. The decompositions of oligo‐2,3‐bis[(2‐hydroxyphenyl) methylene] diamino pyridine–metal complexes occurred in multiple steps. The values of the activation energy (E) and reaction order of the thermal decomposition were calculated by means of several methods, including Coats–Redfern, Horowitz–Metzger, Madhusudanan–Krishnan–Ninan, van Krevelen, Wanjun–Yuwen–Hen–Cunxin, and MacCallum–Tanner on the basis of a single heating rate. The most appropriate method was determined for each decomposition step according to a least‐squares linear regression. The E values obtained by each method were in good agreement with each other. It was found that the E values of the complexes for the first decomposition stage followed the order E_OHPMDAP–Ni > E_OHPMDAP–Cd > E_OHPMDAP–Cu > E_OHPMDAP–Fe > E_OHPMDAP–Zn > E_OHPMDAP–Co > E_OHPMDAP–Cr > E_HPMDAP > E_OHPMDAP. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis and physical properties of poly(l‐lactic acid)‐poly(dimethyl siloxane) multiblock copolymers prepared by direct polycondensation

Multiblock copolymers consisting of poly(l ‐lactic acid) and poly(dimethyl siloxane) were prepared by the polycondensation of oligo(l ‐lactic acid) (OLLA) with dihydroxyl‐terminated oligo(dimethyl siloxane) and dicarboxyl‐terminated oligo(dimethyl siloxane). Copolymers with number‐average molecular weights of 18,000?33,000 Da and various content ratios of oligo(dimethyl siloxane) (ODMS) unit were obtained by changing the feed ratio of these oligomers. A film prepared from the copolymer with an ODMS content ratio of 0.37 exhibited two independent peaks at ?107°C and 37°C in the mechanical loss tangent for temperature dependence, suggesting the formation of microphase separation between the OLLA and ODMS segments. The film had a tensile strength of 3.2 MPa and a high elongation of 132%. The film also exhibited a high strain recovery even after repeated straining. The incorporation of dimethyl siloxane units as multiblock segments was confirmed to improve the flexibility of poly(l ‐lactic acid). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40211.     

Gold(I)‐Catalyzed Tandem Alkoxylation/Lactonization of γ‐Hydroxy‐α,β‐Acetylenic Esters

The formation of 4‐alkoxy‐2(5H)‐furanones was achieved via tandem alkoxylation/lactonization of γ‐hydroxy‐α,β‐acetylenic esters catalyzed by 2 mol% of [2,6‐bis(diisopropylphenyl)imidazol‐2‐ylidine]gold bis(trifluoromethanesulfonyl)imidate [Au(IPr)(NTf₂)]. The economic and simple procedure was applied to a series of various secondary propargylic alcohols allowing for yields of desired product of up to 95%. In addition, tertiary propargylic alcohols bearing mostly cyclic substituents were converted into the corresponding spiro derivatives. Both primary and secondary alcohols reacted with propargylic alcohols at moderate temperatures (65–80 °C) in either neat reactions or using 1,2‐dichloroethane as a reaction medium allowing for yields of 23–95%. In contrast to [Au(IPr)(NTf₂)], reactions with cationic complexes such as [2,6‐bis(diisopropylphenyl)imidazol‐2‐ylidine](acetonitrile)gold tetrafluoroborate [Au(IPr)(CH₃CN)][BF₄] or (μ‐hydroxy)bis{[2,6‐bis(diisopropylphenyl)imidazol‐2‐ylidine]gold} tetrafluoroborate or bis(trifluoromethanesulfonyl)imidate – [{Au(IPr)}₂(μ‐OH)][X] (X=BF₄, NTf₂) – mostly stop after the alkoxylation. Analysis of the intermediate proved the exclusive formation of the E‐isomer which allows for the subsequent lactonization.     

Thiol‐Michael coupling and ring‐opening metathesis polymerization: facile access to functional exo‐7‐oxanorbornene dendron macromonomers

This paper describes the synthesis of the 2‐ and 4‐functional acrylic exo‐7‐oxanorbornene species 2‐((2‐((3aR,7aS)‐1,3‐dioxo‐1,3,3a,4,7,7a‐hexahydro‐2H‐4,7‐epoxyisoindol‐2‐yl)ethoxy) carbonyl)‐2‐methylpropane‐1,3‐diyl diacrylate and (((2‐((2‐((3aR,7aS)‐1,3‐dioxo‐1,3,3a,4,7,7a‐hexahydro‐2H‐4,7‐epoxyisoindol‐2‐yl)ethoxy) carbonyl)‐2‐methylpropane‐1,3‐diyl)bis(oxy))bis(carbonyl))bis(2‐methylpropane‐2,1,3‐triyl) tetraacrylate, and their use as common precursors for the preparation of a small library of dendronized thioether adducts via nucleophile‐mediated thiol‐Michael coupling chemistry. We subsequently demonstrate that the dendronized monomers can be (co)polymerized via ring‐opening metathesis polymerization employing Grubbs'‐type Ru‐based initiators to give novel functional dendronized (co)polymers of predictable molecular weights and acceptable dispersities (?_M = _w/ _n). © 2013 Society of Chemical Industry     

Synthesis,characterization, and antimicrobial properties of oligo‐4‐[(pyridine‐3‐yl‐methylene) amino] phenol

The oxidative polycondensation reaction conditions of 4‐[(pyridine‐3‐yl‐methylene) amino]phenol (4‐PMAP) were studied using H₂O₂, atmospheric O₂, and NaOCl oxidants in an aqueous alkaline medium between 30°C and 90°C. Synthesized oligo‐4‐[(pyridine‐3‐yl‐methylene) amino] phenol (O‐4‐PMAP) was characterized by ¹H‐, ¹³C NMR, FTIR, UV–vis, size exclusion chromatography (SEC), and elemental analysis techniques. The yield of O‐4‐PMAP was found to be 32% (for H₂O₂ oxidant), 68% (for atmospheric O₂ oxidant), and 82% (for NaOCl oxidant). According to the SEC analysis, the number–average molecular weight, weight–average molecular weight, and polydispersity index values of O‐4‐PMAP was found to be 5767, 6646 g mol^?1, and 1.152, respectively, using H₂O₂, and 4540, 5139 g mol^?1, and 1.132, respectively, using atmospheric O₂, and 9037, 9235 g mol^?1, and 1.022, using NaOCl, respectively. According to TG and DSC analyses, O‐4‐PMAP was more stable than 4‐PMAP against thermal decomposition. The weight loss of O‐4‐PMAP was found to be 94.80% at 1000°C. Also, antimicrobial activities of the oligomer were tested against B. cereus, L. monocytogenes, B. megaterium, B. subtilis, E. coli, Str. thermophilus, M. smegmatis, B. brevis, E. aeroginesa, P. vulgaris, M. luteus, S. aureus, and B. jeoreseens. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3327–3333, 2006     

Poly(styrene–divinyl benzene)‐immobilized Fe(III) complex of 1,3‐bis(benzimidazolyl)benzene: Efficient catalyst for the photocatalytic degradation of xylenol orange

A polymer‐supported Fe(III) complex of 1,3‐bis(benzimidazolyl)benzene [PS–Fe(III)BBZNH] was used in the photodegradation of xylenol orange (XO) dye with H₂O₂ under UV irradiation. The catalyst was synthesized and characterized by elemental analysis, and Fourier transform infrared, far‐infrared, and UV–visible–diffuse reflectance spectroscopy, Scanning electron microscopy, Brunauer–Emmett–Teller surface area measurements, thermogravimetric analysis, and magnetic measurements. An octahedral coordination around Fe(III) was confirmed by electronic spectral data, and a decrease in the intensity of the ν_CH2Cl peak in PS–Fe(III)BBZNH was observed compared to the polymer support; this indicated the binding of the ligand to the support. An array of experiments were carried out to assess the influence of various reaction parameters on its photocatalytic performance to ensure maximum dye degradation. The maximum photocatalytic activity was observed at pH 8 with 125 mg of catalyst, 300 ppm of XO, and 200 ppm of H₂O₂ with complete mineralization after 90 min, as confirmed by chemical oxygen demand measurements. Furthermore, the reactions were repeated under sunlight and under dark conditions to check the photocatalytic efficiency of PS–Fe(III)BBZNH. It displayed better catalytic performance compared than the unsupported complex, PS–Cu(II)BBZNH [Cu(II) complex of 1,3‐bis(benzimidazolyl)benzene], and PS–VO(IV)BBZNH [VO(IV) complex of 1,3‐bis(benzimidazolyl)benzene]. PS–Fe(III)BBZNH could be recycled for up to seven runs. A tentative mechanism involving ·OH radical was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46480.     

Synthesis and characterization of light‐absorbing cyclopentadithiophene‐based donor–acceptor copolymers

Cyclopentadithiophene and benzothiadiazole based donor–acceptor polymers are fast emerging as the most promising class of materials for organic solar cells. Here we report on a series of Cyclopentadithiophene and benzothiadiazole based conjugated polymers, namely poly[4,7‐bis(4,4‐dioctyl‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene‐2‐yl)benzo[1,2,5]thiadiazole] (P1), poly[4,7‐bis(4,4‐dioctyl‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene‐2‐yl)benzo[1,2,5]thiadiazole‐alt‐9‐(heptadecan‐9‐yl)‐2,7‐bis(4,4,5,5‐tetramethyl)‐1,3,2‐dioxaborolan‐2‐yl)‐9H‐carbazole] (P2) and poly[4,7‐bis(4,4‐dioctyl‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene‐2‐yl)benzo[1,2,5]thiadiazole‐alt‐5,11‐bis(2‐hexyldecyl)‐3,9‐bis(4,4,5,5‐tetramethyl)‐1,3,2‐dioxaborolan‐2‐yl)‐5,11‐dihydroindolo[3,2‐b]carbazole] (P3), with alternating donor and acceptor units and discuss their photophysical and electrochemical properties. Stille coupling of 2‐tributylstannyl‐4,4‐dioctylcyclopenta[2,1‐b:3,4‐b′]dithiophene with 4,7‐dibromobenzo[1,2,5]thiadiazole generated the alternating donor–acceptor monomer 4,7‐bis(4,4‐dioctyl‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene‐2‐yl)benzo[1,2,5]thiadiazole (CPDT‐BT‐CPDT). Homopolymer P1 of CPDT‐BT‐CPDT was synthesized by oxidative polymerization using FeCl₃. Copolymers P2 and P3 were synthesized by palladium‐catalysed Suzuki polycondensation. The synthesized polymers showed good solubility in common organic solvents, and UV‐visible measurements showed that the absorption maxima of the polymers lie in the range 624 to 670 nm. The energy gaps of these polymers were found to lie in the range 1.29 to 1.50 eV. Gel permeation chromatography measurements against polystyrene standards showed the number‐average molecular weight to be in the range (2.2–6.0) × 10⁴ g mol^?1. Thermogravimetric analysis showed the polymers to possess high thermal stability. A preliminary study of photodiode devices prepared using polymers P1, P2 and P3 when blended with the PC₇₁BM electron acceptor found that P2 is the optimum chemical structure for pursuing further device optimization.© 2015 Society of Chemical Industry     

Retracted: Palladium‐Catalyzed Decarboxylative Selective Acylation of 4H‐Benzo[d][1,3]oxazin‐4‐one Derivatives with α‐Oxo Carboxylic acids via Preferential Cyclic Imine‐N‐Directed Aryl C−H Activation

The benzoxazine scaffolds are of much interest as they are found in a large array of natural products and pharmaceutical drugs with diverse activities. We have developed a palladium‐catalyzed decarboxylative selective mono‐ and bis‐acylation of 4H‐benzo[d][1,3]oxazin‐4‐one derivatives with α‐oxo carboxylic acids via preferential cyclic imine‐N‐directed C−H activation. 2‐Aryl‐4H‐benzo[d][1,3]oxazin‐4‐one was acylated with a variety of substituted phenylglyoxylic acids to produce the corresponding products. It was observed that electron‐donating groups (CH₃, OCH₃) at any position of the aromatic ring of phenylglyoxylic acid provided good to excellent yields, whereas phenylglyoxylic acids containing electron‐withdrawing groups (COCH₃, CN, NO₂) gave the products in moderate yields. Interestingly when the reaction was performed with silver triflate (AgOTf) in place of silver nitrate (AgNO₃) in the presence of 4 equivalents of glyoxylic acid, the bis‐acylated product was obtained together with a small amount of mono‐acylated product. This is the first report of acylation of 2‐aryl‐4H‐benzo[d][1,3]oxazin‐4‐ones via C−H activation. The notable features of this reaction are acylation with more challenging heteroarene‐oxo carboxylic acids and alkyl oxo carboxylic acids. This new protocol provides an easy and efficient access to a variety of o‐acyl‐4H‐benzo[d][1,3]oxazin‐4‐one derivatives which are of pharmaceutical importance.

     

Synthesis and spectroelectrochemistry of dithieno(3,2‐b:2′,3′‐d)pyrrole derivatives

New π‐conjugated polymers containing dithieno(3,2‐b:2′,3′‐d)pyrrole (DTP) were successfully synthesized via electropolymerization. The effect of structural differences on the electrochemical and optoelectronic properties of the 4‐[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl]aniline (DTP–aryl–NH₂), 10‐[4H‐dithiyeno(3,2‐b:2′,3′‐d)pirol‐4‐il]dekan‐1‐amine (DTP–alkyl–NH₂), and 1,10‐bis[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl] decane (DTP–alkyl–DTP) were investigated. The corresponding polymers were characterized by cyclic voltammetry, NMR (¹H‐NMR and ¹³C‐NMR), and ultraviolet–visible spectroscopy. Changes in the electronic nature of the functional groups led to variations in the electrochemical properties of the π‐conjugated systems. The electroactive polymer films revealed redox couples and exhibited electrochromic behavior. The replacement of the DTP–alkyl–DTP unit with DTP–aryl–NH₂ and DTP–alkyl–NH₂ resulted in a lower oxidation potential. Both the poly(10‐(4H‐Dithiyeno[3,2‐b:2′,3′‐d]pirol‐4‐il)dekan‐1‐amin) (poly(DTP–alkyl–NH₂)) and poly(1,10‐bis(4H‐dithieno[3,2‐b:2′,3′‐d]pyrrol‐4‐yl) decane) (poly(DTP–alkyl–DTP)) films showed multicolor electrochromism and also fast switching times (<1 s) in the visible and near infrared regions. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40701.     

Polymerization of 4‐(4′‐N‐1,8‐naphthalimidophenyl)‐1,2,4‐triazolidine‐3,5‐dione with diisocyanates

4‐(4′‐Aminophenyl)‐1,2,4‐triazolidine‐3,5‐dione ( 1 ) was reacted with 1,8‐naphthalic anhydride ( 2 ) in a mixture of acetic acid and pyridine (3 : 2) under refluxing temperature and gave 4‐(4′‐N‐1,8‐naphthalimidophenyl)‐1,2,4‐triazolidine‐3,5‐dione ( NIPTD ) ( 3 ) in high yield and purity. The compound NIPTD was reacted with excess n‐propylisocyanate in N,N‐dimethylacetamide solution and gave 1‐(n‐propylamidocarbonyl)‐4‐[4′‐(1,8‐naphthalimidophenyl)]‐1,2,4‐triazolidine‐3,5‐dione ( 4 ) and 1,2‐bis(n‐propylamidocarbonyl)‐4‐[4′‐(1,8‐naphthalimidophenyl)]‐1,2,4‐ triazolidine‐3,5‐dione ( 5 ) as model compounds. Solution polycondensation reactions of monomer 3 with hexamethylene diisocyanate ( HMDI ), isophorone diisocyanate ( IPDI ), and tolylene‐2,4‐diisocyanate ( TDI ) were performed under microwave irradiation and conventional solution polymerization techniques in different solvents and in the presence of different catalysts, which led to the formation of novel aliphatic‐aromatic polyureas. The polycondensation proceeded rapidly, compared with conventional solution polycondensation, and was almost completed within 8 min. These novel polyureas have inherent viscosities in a range of 0.06–0.20 dL g^?1 in conc. H₂SO₄ or DMF at 25°C. Some structural characterization and physical properties of these novel polymers are reported. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2861–2869, 2003     

Synthesis,characterization, and thermal degradation of oligo‐2‐(morpholinoiminomethyl)phenol and its Pb(II) complex compound

The oxidative polycondensation reaction conditions of 2‐(morpholinoiminomethyl)phenol were studied with H₂O₂, air O₂, and sodium hypochloride (NaOCl) oxidants in an aqueous alkaline medium between 40 and 90°C. The structure of oligo‐2‐(morpholinoiminomethyl)phenol was characterized with ¹H‐ and ¹³C‐NMR, Fourier transform infrared, ultraviolet–visible, size exclusion chromatography, and elemental analysis techniques. Under the optimum reaction conditions, the yield of oligo‐2‐(morpholinoiminomethyl)phenol was 28% for the H₂O₂ oxidant, 12% for the air O₂ oxidant, and 58% for the NaOCl oxidant. According to the size exclusion chromatography analysis, the number‐average molecular weight, weight‐average molecular weight, and polydispersity index of oligo‐2‐(morpholinoiminomethyl)phenol were 2420 g/mol, 2740 g/mol, and 1.187 with H₂O₂, 1425 g/mol, 2060 g/mol, and 1.446 with air O₂, and 1309 g/mol, 1401 g/mol, and 1.070 with NaOCl, respectively. Thermogravimetry/dynamic thermal analysis showed that the oligo‐2‐(morpholinoiminomethyl)phenol–lead complex compound was more stable than 2‐(morpholinoiminomethyl)phenol and oligo‐2‐(morpholinoiminomethyl)phenol against thermal degradation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:3795–3804, 2006     

Preparation and photocurrent generation of an electrostatically self‐assembled film of hemicyanine and poly(4‐styrenesulfonic acid‐co‐maleic acid)

In this article, we report on electrostatically self‐assembled thin films prepared by the alternative immersion of quartz‐coated and indium tin oxide coated glass substrates in aqueous solutions of a copolymer of poly(4‐styrenesulfonic acid‐co‐maleic acid) (PSSMA) and a hemicyanine of (E)?1,1′‐(propane‐1,3‐diyl)bis{4‐[4‐(dimethylamino)styryl]pyridinium} bromide (H³Br₂). The films were studied by means of ultraviolet–visible absorption and X‐ray photoelectron spectroscopies, scanning electron microscopy, and photoelectrochemical measurements. When irradiated with white light, the PSSMA/H³ monolayer film gave a stable cathodic photocurrent. The effects of the applied bias voltages, layer numbers of the (PSSMA/H³)_n films (where n stands for the number of bilayer films on both sides of the substrates), light intensities, pH value, and electron acceptor on the photocurrent generation of the (PSSMA/H³)_n film were examined. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39871.     

Metallkomplexe mit biologisch wichtigen Liganden. CXXIII. Darstellung von Isophthaloyl‐ und Terephthaloyl‐di‐[(β,γ,δ)‐amino‐α‐aminocarboxylat]‐verbrückten zweikernigen Ruthenium‐, Rhodium‐ und Iridium‐Halbsandwich‐Komplexen

The reaction of the Cu(II) bis N,O‐chelate‐complexes of L‐2,4‐diaminobutyric acid, L‐ornithine and L‐lysine {Cu[H₂N–CH(COO)(CH₂)_nNH₃]₂}²⁺(Cl^–)₂ (n = 2–4) with terephthaloyl dichloride or isophthaloyl dichloride gives the polymeric complexes {‐OC–C₆H₄–CO–NH–(CH₂)_n–CH(nh₂)(COO)Cu(OOC)(NH₂)CH–CH₂)_n–NH‐}_x 1 – 5 . From these the metal can be removed by precipitation of Cu(II) with H₂S. The liberated ω,ω′‐N,N′‐diterephthaloyl (or iso‐phthaloyl)‐diaminoacids 6 – 10 react with [Ru(cymene)Cl₂]₂, [Ru(C₆Me₆)Cl₂]₂, [Cp*RhCl₂]₂ or [Cp*IrCl₂]₂ to the ligand bridged bis‐amino acidate complexes [L_n(Cl)M–(OOC)(NH₂)CH–(CH₂)_nNH–CO]₂–C₆H₄ 11 – 14 .     

Synthesis of poly(methylphenylsiloxane) rich in syndiotacticity by Rh‐catalysed stereoselective cross‐dehydrocoupling polymerization of optically active 1,3‐dimethyl‐1,3‐diphenyldisiloxane derivatives

Cross‐dehydrocoupling reactions of (R)‐methyl(1‐naphthyl)phenylsilane (>99%ee) with (S)‐methyl(1‐naphthyl)phenylsilanol (>99% ee) proceeded with 82–99% retention of configuration of chiral silicon centres in the presence of various Rh‐catalysts. Cross‐dehydrocoupling polymerization of 1,3‐dimethyl‐1,3‐diphenyl‐1,3‐disiloxanediol with 1,3‐dihydro‐1,3‐dimethyl‐1,3‐diphenyl‐1,3‐disiloxane gave poly(methylphenylsiloxane) of moderate molecular weight in toluene at 60 °C in the presence of [RhCl(cod)]₂ (5.0 mol%) and triethylamine (1.0 equivalent). Assignment of the triad signals of the resulting polymer was made by ¹H NMR spectroscopy of the methyl proton (I = 0.04, H = 0.09 and S = 0.14 ppm) and ¹³C NMR spectroscopy of the ipso carbon of the phenyl group (S = 136.7, H = 136.9, and I = 137.1 ppm). Although the reaction of optically pure (S,S)‐1,3‐dimethyl‐1,3‐diphenyl‐1,3‐disiloxanediol with 1,3‐dihydro‐1,3‐dimethyl‐1,3‐diphenyl‐1,3‐disiloxane [(S,S):(S,R):(R,R)] = 84:16:0] gave a poly(methylphenylsiloxane) of rather low molecular weight, its triad tacticity was found to be rich in syndiotacticity (S:H:I = 60:32:8) by ¹³C NMR spectroscopy. © 2001 Society of Chemical Industry