Phosphorus-Containing Dendrimers: Synthesis and Properties

Several series of phosphorus-containing dendrimers have been designed to study the variation of their properties, depending on the type, the location (surface, branches, core, and cavities), and the number of functions implied.     

Synthesis and Characterization of Novel Aromatic Polyethers from Tetraphenylated Five-Membered Heterocycle-Containing Diols and Activated Aromatic Dihalides

Abstract

New aromatic polyethers having inherent viscosities of 0.23-0.73 dL/g were synthesized from combinations of three tetraphenylated five-membered heterocycle-containing diols, 2,5-bis(4-hydroxyphenyl)-3,4-diphenyl-furan, -pyrrole, and -thiophene, and three activated aromatic dihalides, 4,4′-difluorobenzophenone, bis(4-hydroxy-phenyl) sulfone, and 2,6-difluorobenzonitrile, by aromatic nucleophilic substitution poly-condensation. These aromatic polyethers, which have an amorphous nature, were soluble in a wide range of organic solvents. They had glass transition temperatures in the 182 to 250°C range with no weight loss below 400°C in either air or nitrogen atmospheres.     

Synthesis and Inclusion Properties of Macrocyclic Polyethers Containing Phosphonic Groups

Abstract

Three novel polyether macrocycles II-IV bearing phosphonic groups have been synthesised in satisfactory yields. Macrocycle II was found to form a 1:1 inclusion compound with cyclohexane and thus was easily isolated from the reaction mixture as a clathrate. The crystal and molecular structure of the cyclohexane solvate has been determined by single crystal X-ray analyses and refined to an R of 0.028 for 3199 reflection. The compound is monoclinic, space group P2₁n with a = 15.886(6) Å, b = 11.657(5) Å, c = 18.621 (6) Å, β = 90.12(3)°, Z = 2. The whole molecule exhibits a great deal of disorder and the different conformations were modelled as consisting of two different primary conformers with population approximately 60:40.     

Synthesis of Arsamacrocyclic Polyethers

Thesynthesisofmacrocycliccompoundsandthestudyofguestc0mplexati0nbehavi0rofsuchhostshavebeenanactiveareaofresearchinrecentyears.Ourinteresthasbeenfocussedonheter0macrocyclicpolyetherswhichhaves0ftligatingsites,appropriatef0rcoordinationoftransitionmetals.lnpaFticuIar,heter0macrocycleswhichcontaintricoordinatedarsenicatomsassoftligatingsitesn0t0nlyp0ssessahighcomplex-formingcapacitybutcanalsostabilizetransitionmetalsintheirlowestvaIencestates.Aseriesofarsamacrocyclicpolyethershavebeensynthesize…     

含偶氮苯生色团的聚醚的合成与热致液晶性质

β－氯乙基缩水甘油醚（ＧＣＥ）和ＧＣＥ／羟丁基乙烯基醚（ＨＢＶＥ）分别通过阳离子聚合、光引发共聚合,获得两种聚醚,然后再分别与４－硝基－４’－羟基偶氦苯（ＮＨＡ）反应,制备了两种侧链含偶氦苯生色团的液晶聚合物（ＰＡＥＧ、ＰＡＶ）。用ＦＴＩＲ、＾１Ｈ－ＮＭＲ和ＥＡ对其化学结构及生色团含量进行了表征,以ＰＯＭ,ＤＳＣ、ＴＧＡ和ＷＡＸＤ对聚合物介晶相转变温度、织构、热稳定性及相行为进行了研究。结果表明,     

超支化聚醚的合成与应用

超支化聚醚以其独特的结构与性能而成为高分子研究的热点。本文对近年来HBPE的合成方法及应用研究进行了综述。目前超支化聚醚的制备方法主要包括在缩合反应、开环聚合反应、及质子转移等其它聚合反应。超支化聚醚的应用研究领域非常广阔,主要包括聚合物电解质、生物医药、无机物表面改性、荧光功能高分子材料、聚合物改性以及负载、液晶、水凝胶等其它功能材料方面显示出了巨大的应用潜力。本文还对超支化聚醚今后的应用前景进行了展望。     

Syntheses and Complexing Properties of Polyethers

Diaza-18-crown-6 with two 8-hydroxyquinolines as side arms show high selective complexing ability with metal ions^[1,2] and with two aminophenols exhibit strange property^[3]. 8 diaza-18-crown-6 ethers containing sidearms^[4] and 7 podands were synthesized. Their complexing ability with metal ions were studied, the results show that they present high complexing capability for metal ions. The polyethers containing 8-hydroquinoline fragment show high selectivities for Hg²⁺,Ni²⁺ and their complexes with Eu³⁺ and Tb³⁺ show strong luminescence.     

Synthesis and Optical Properties on a Series of Polyethers Incorporating Terfluorene Segments and Methylene Spacers

A series of polyethers consisting of a modified terfluorenediol connected with a nonconjugated spacer were synthesized and characterized in respect to their thermal, electrochemical, optical and morphological properties. The polymers were further investigated as thin deposits with the use of the FT‐IR technique after thermal (200°C for 30 min) and photo‐oxidation treatment. After thermal treatment no generation of the carbonyl stretching mode of the fluorenone moiety is observed, while after photo‐oxidation in various times (between 5 to 30 min) the appearance of the fluorenone unit is well established. Furthermore, the length of the flexible spacer used influenced the optical properties of the polyethers after thermal treatment. In particular, odd ones showed more intensely the low energy emission band at 520 nm after the thermal treatment in contrast to even ones.     

Synthesis of Phosphorus-Containing Carboxylic Acid Derivatives

Abstract

Phosphorus-containing carboxylic acids are of great interest as potential antiviral substances (1). Thus, the search for the simple and technological methods of their synthesis draws much attention.     

含叔丁基可溶性芳香聚酰胺的制备及其性能研究

采用含叔丁基二胺的单体3,3′-二叔丁基-4,4′-二氨基二苯基-4″-叔丁基苯基甲烷(TADBP)分别与萘-1,4-二甲酸、间苯二甲酸和4,4-二苯醚二甲酸3种二酸单体通过Yamazaki膦酰化法缩聚制得一系列新型可溶性芳香聚酰胺(PA)。通过FT-IR、~1 H-NMR、TG、DSC等测试手段研究了含叔丁基芳香聚酰胺的结构与性能,以及聚合物结构对其溶解性能、热性能的影响。结果表明:PA具有优异的溶解性能,常温下不仅能溶于高沸点的N-甲基吡咯烷酮(NMP)、N,N-二甲基乙酰胺(DMAc)、N,N-二甲基甲酰胺(DMF)、二甲基亚砜(DMSO)等强极性溶剂中,加热条件下甚至能溶于四氢呋喃、氯仿、二氯甲烷等低沸点溶剂;同时,PA还具有良好的热性能,玻璃化转变温度(Tg)为188~193℃,氮气氛围下失重5%和10%时的热失重温度分别为391~416℃和404~437℃。     

Synthesis of Energetic Polyethers from Halogenated Precursors

In the solid rocket propellant formulations an important component is the polymeric binder. Actually, the most used binder is hydroxyl-terminated polybutadiene. However, the research is oriented toward the use of energetic polymers which, in addition to the binder function, should improve the propulsion capability of the propellant. In this respect, good candidates are oxetanic polyethers with azidic functionalities in their side chains. Considering the explosive character of such materials, their synthesis must be designed with attention to the safety of the process. In this note, the preparation of azidic copolymers is described and different synthetic strategies are discussed and compared.     

Synthesis and Properties of Novel Aromatic Copolyamides Containing Phthalazinone Moiety

A series of novel aromatic copolyamides were synthesized by the direct polycondensation of 2‐(4‐carboxyphenyl)‐4‐[4‐(4‐carboxyphenoxyl)phenyl]‐phthalazinone (1), terephthalic acid (TPA), and four commercial diamines. The inherent viscosities of the polyamides were between 0.79～1.56 dL/g. Introduction of the non‐coplanar phthalazinone segments into the main chains remarkably decreased the crystallinity and improved the solubility of the copolyamides. When the percentage of 1 in the diacid monomers was above 50%, the copolymers were soluble in aprotic polar solvents, such as N‐methyl‐pyrrolidinone and N,N‐dimethylacetamide. The copolyamides showed high thermal properties associated with the glass transition temperatures in the range of 276～337°C and 10% wt loss temperatures in nitrogen over 496°C. Some polymer films cast from NMP solution had tensile strengths up to 123.4 MPa, initial moduli up to 2.10 GPa, and elongation at break values up to 9.6%.     

链延长型芳杂环双马来酰亚胺树脂的合成及性能

从分子结构出发,设计合成了含酞/芴Cardo环结构、1,3,4-噁二唑不对称结构共计3类10种新型链延长型双马来酰亚胺(BMI),采用核磁共振(NMR)、红外光谱(IR)、示差扫描量热仪(DSC)、热失重分析仪(TGA)、动态力学分析仪(DMA)等技术表征了BMI树脂的化学结构、固化行为以及固化物的热稳定性和动态力学性能,探讨了分子结构与性能关系.研究结果表明含酞(芴)Cardo结构BMI在普通低沸点有机溶剂中具有良好的溶解性能;含1,3,4-噁二唑结构BMI由于具有不对称分子结构导致两端官能团反应活性存在明显差异;3类BMI的固化物均具有优异耐热性和热稳定性.     

Thermal Behavior and Primary Degradation Mechanism of Some Aromatic Polyethers with Semi-flexible Chain

The present paper describes a thermogravimetric study combined with mass spectrometry of some aromatic polyethers and copolyethers in order to obtain information on the degradation mechanism. The investigated polymers were synthesized starting from 3,3-bis(chloromethyl) oxetane and various bisphenols: 4,4'-dihydroxyazobenzene, 4,4'-dihydroxydiphenyl, bisphenol A and 4,4'-dihydroxydiphenylether. The presence of an oxetanic spacer in the structure, permitting the opening of the cycle, induces more complications in the characterization procedure. But, due to the possibilities relative to the modification of polymers or cross-linking reactions, the presence of the oxetanic moiety may offer some advantages. Out of all the investigated polymers, those containing azobenzenic moieties have the lower thermostability. If the chain flexibility is augmented, the degradation mechanism is based on chain transfer reactions. All polymers present higher thermostability in an argon atmosphere. Based on mass spectra, a degradation mechanism sustained with the assumption that the oxetanic unit is the most labile was proposed. The opening of the oxetanic cycle begins with the most tensioned bond (-C-CH₂-) and generates across-linking process, which is more evident if the polymer melts below 200°C. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis of Phosphorus-Containing Acetamidines Bearing Pharmacophoric Fragments

Russian Journal of General Chemistry - The reactions of N-adamant-1-ylketeniminophosphonates with heterocyclic amines (pyrrolidine, morpholine, 2,6-dimethylpiperidine, 4-ethylpiperazine,...     

Fulvalene-Based Polycyclic Aromatic Hydrocarbon Ladder-Type Structures: Synthesis and Properties

Polycyclic aromatic hydrocarbons (PAHs) have found strong interest for their electronic properties and as model systems for graphene. While PAHs have been studied intensively as single units, here PAHs were constructed in ladder-type arrangements using cross-conjugated fulvalene and dithiafulvalene motifs as connecting units and moving forward a convenient synthetic approach for dimerizing (thio)ketones into olefins by the action of Lawesson's reagent. Some of the PAHs can also be regarded as “super-extended” tetrathiafulvalenes (TTFs) with some of the largest cores ever explored, being multi-redox systems that exhibit both reversible oxidations and reductions. Concomitant absorption redshifts were observed when expanding the ladder-type structures from one to two to three indenofluorene units, and optical and electrochemical HOMO-LUMO gaps were found to correlate linearly. Various conformations (and solid-state packing arrangements) were studied by X-ray crystallography and computations.     

有机磷类阻燃剂的合成及应用进展

由于有机磷阻燃剂具有高效、低毒、无污染及无烟等特点,该领域的研究在国内外得到极大的关注,已经在合成和应用等方面取得了显著成就。 本文对磷系阻燃剂的阻燃机理及近年来磷系阻燃剂的应用进展作了简要综述。 分别综述了各类有机含磷阻燃剂的研究进展,并提出了有机磷阻燃剂今后的发展方向。