Design and synthesis of organosoluble and transparent polyimides containing bulky substituents and noncoplanar structures

A new diamine monomer, 3,3′‐diisopropyl‐4,4′‐diaminophenyl‐4″‐phenyltouene, was designed, synthesized, and then polymerized with five commercial dianhydrides to obtain a series of novel polyimides via a one‐step method. The obtained polymers showed excellent solubility in most common solvents, even in low‐boiling solvents, such as chloroform, dichloromethane, and tetrahydrofuran. They exhibited a high thermal stability with the glass‐transition temperature in the range 262–318°C and 10% weight loss temperatures in the range 464–488°C under a nitrogen atmospheres. Meanwhile, these polymer films also displayed a high optical transparency with a cutoff wavelength in the range 305–365 nm; prominent mechanical properties with a tensile strength of 65.6–94.9 MPa, a Young's modulus of 1.6–2.8 GPa, and an elongation at break of 9.3–13.7%; a low dielectric constant in the range of 2.91–3.18 at 1 MHz; and an outstanding hydrophobicity with a contact angle above 90.6°. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43266.     

Synthesis and characterization of poly(amide imide)s containing cyclohexylidene moieties with bulky substituents

Novel poly(amide imide)s (PAI) containing alkyl-substituted cyclohexylidene moieties were synthesized by conventional polycondensation of trimellitic anhydride chloride with novel aromatic diamines followed by chemical imidization using acetic anhydride and pyridine. The inherent viscosities of the resulting PAIs are relatively high and range from 71 to 112 mL g^–1. The prepared PAIs show excellent thermal stability and good solubility. The glass transition temperatures (T_g) measured by DSC are observed in the range of 312–342°C. Furthermore, all the polymers are readily soluble in less hygroscopic organic solvents like cyclohexanone, γ-butyrolactone as well as aprotic polar solvents.     

Gas permeability of polyacetylenes with bulky substituents

Polymer Bulletin - In search of new materials for oxygen-enrichment membranes, high polymers of acetylenes with bulky substituents [2-octyne...     

含大位阻基团苯氧亚胺锆络合物的合成及其催化乙烯聚合

以含大位阻基团取代苯酚和使用Fe-Al-MCM-41介孔分子筛或铝粉通过傅克烷基化反应引入大位阻基团的取代苯酚为原料,制备得到3种苯氧亚胺锆络合物e、j、n。以MAO为助催化剂,考察了聚合温度、铝/锆物质的量比、乙烯压力对络合物催化活性以及聚合物分子量的影响。结果表明,在70℃,n(Al)/n(Zr)=6 000,乙烯压力为0.8 MPa条件下,络合物j的催化活性最高,为220 kgPE/(mmol·Zr·h),聚乙烯的粘均分子量117×10~4g/mol。     

不同活化方式下PMS对污泥脱水性能的影响及机理分析

以单过硫酸盐(PMS)氧化处理城市污水厂剩余污泥,考察PMS投加量、活化温度、活化碱的种类、碱/PMS摩尔比以及热与碱联合活化下对污泥的含水率和SCOD的影响,并采用扫描电镜等对脱水性能进行表征。结果表明,热与碱联合活化PMS对污泥脱水效果大于单一活化方式下对污泥的脱水效果,达到最佳脱水效果时PMS和KOH的最佳投加量分别为0.6,0.3 mmol/g,温度为80℃。处理后,污泥絮体孔状结构丰富,相对分子量较大的污染物被分解,污泥结合水降低,自由水增加,更有利于后续干燥。     

Synthesis and characterization of half-sandwich Ir and Ru complexes containing Mnt ligand (Mnt = maleonitriledithiolate)

The reaction of [Cp¹IrCl₂]₂ and [(p-Cymene)RuCl₂]₂ with disodium maleonitriledithiolate (Na₂Mnt) yield the 16-electron complexes Cp¹Ir(Mnt) (1) and [(p-Cymene)Ru(Mnt)] (2). Complexes 1 and 2 can further react with PPh₃ to form the corresponding 18-electron complexes Cp¹Ir(Mnt)PPh₃ (3) and [(p-Cymene)Ru(Mnt)PPh₃] (4). All complexes have been fully characterized by IR and NMR spectroscopy, as well as elemental analysis. The molecular structures of 1 and 4 have been confirmed by X-ray crystallography.     

Ceramics of good thermal strength from fused powders of yttrium and scandium oxides

Conclusions An investigation was carried out of the conditions for producing refractories from electrofused Y₂O₃ by casting. Components of intricate shape were produced at a firing shrinkage of about 6%.The conditions were refined for producing refractories with good thermal strength from fused powders of Y₂O₃ and Sc₂O₃ by semidry molding.Translated from Ogneupory, No. 5, pp. 57–59, May, 1976.     

钪配合物催化丙烯与月桂烯的共聚合

研究了两种钪配合物(C5Me4SiMe3)Sc(CH2C6H4NMe2-o)2(记作钪配合物1,Me为甲基)和(C5Me4SiMe3)Sc(CH2SiMe3)2(THF)(记作钪配合物2,THF为四氢呋喃)催化丙烯与月桂烯共聚合的性能.结果表明:在室温及丙烯压力为0.6?MPa时,通过调控月桂烯的用量,采用钪配合物1和...     

New lipophilic cyclo- and poly-phosphazenes containing surfactant substituents

The reaction of the sodium salt of the commercially available surfactant Igepal CA 210^™ with hexachlorocyclotriphosphazene, N₃P₃Cl₆ (1) and poly(dichlorophosphazene), [—P(Cl₂)=N—]_n (Publisher's note: for graphical representation please see printed journal or the Acrobat PDF version on this website.) affords lipophilic cyclo- and poly-phosphazenes SSCP (2) and SSPP (4), respectively. These materials, containing a short chain oligo etheroxy side group while being completely insoluble in water, are soluble in a wide range of solvents ranging from hexane to chloroform. The polymer, SSPP (4) forms polymer–metal salt complexes with lithium salts. DC conductivity measurements by a complex impedance method have been carried out. The maximum conductivity observed for SSPP–LiClO₄ (O: Li ratio, 6:1) is 1·0×10^-6Scm^-1 at 348K. © 1998 SCI.     

Ring opening reactions of glycidyl methacrylate copolymers to introduce bulky organosilicon side chain substituents

Summary Glycidyl methacrylate (GMA) random copolymers with methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate (BA), methyl methacrylate (MMA), ethyl methacrylate (EMA) and n-butyl methacrylate (BMA) were synthesized by solution free radical polymerizations, at 70±1 °C using α,α’-azobis(isobutyronitrile) as an initiator to give the copolymers I – VI in good yields. The copolymer compositions were obtained using related ¹H NMR spectra and the polydispersity indices of the copolymers determined using gel permeation chromatography (GPC). Tris(trimethylsilyl)methyl (Tsi=trisyl) groups were then covalently attached to the obtained copolymers as side chains by ring opening reaction between excess of TsiLi and expoxide groups of GMA units to give the copolymers I_Tsi – VI_Tsi in good yields. In the coupling reaction, the TsiLi reacted selectively with the epoxy groups of the backbone polymer rather than with the carbonyl groups of the backbone. This method of preparing functionalized silanes is limited by the readiness with which TsiLi abstracts a proton, if one is available, rather than attacks at carbon. In addition in the reaction with epoxides, the product alkoxide can transfer a silyl group from carbon to oxygen or ring opening polymerization. However these were shown not to occur at the conditions of interest here. The epoxy group possesses a higher reactivity for the TsiLi than the ester and chloromethyl groups. The ring opening reaction between the epoxy group and the TsiLi is simple and fast. All the resulted polymers were characterized by FT-IR and ¹H NMR spectroscopic techniques. The glass transition temperature (Tg) of all copolymers was determined by differential scanning calorimetry (DSC) apparatus. All the polymers containing trisyl groups showed a high glass transition temperature in comparison with unmodified copolymers (I – VI). Attaching the tris(trimethylsilyl)methyl group to macromolecular chain should lead to important modifications of polymer properties such as gas permeability and perm selectivity parameters.     

Preparation and properties of aromatic polyamide homologs containing chlorine substituents

In order to study systematically the effect of halogen substituents on both the solubility and the thermal stability of aromatic polyamides, new diamine monomers have been synthesized by introducing chlorine groups onto various positions of 4,4′‐diaminobenzanilide for the preparation of chlorinated aromatic polyamides. The monochlorinated aromatic polyamides, i.e., P‐LCl and P‐RCl, exhibited liquid crystalline property in 100% sulfuric acid solution in the temperature range from 40 and 60°C. However, the dichlorinated sample, i.e. P‐LRCl, did not exhibit the liquid crystalline property due to the bulkiness of two chlorine groups. Both P‐LCl and P‐RCl exhibited unimodal decomposition behavior in contrast to the chlorinated poly(p‐phenylene terephthalamide) (PPTA) that has been known to show bimodal decomposition behavior. The decomposition onset temperature of both P‐LCl and P‐RCl was 567°C, which was higher than 549°C of unchlorinated polyamide, P‐NCl, but the same as that of PPTA. The char yield was about 50% for both P‐LCl and P‐RCl and higher than 40% of both PPTA and P‐NCl. In the case of P‐LRCl, the decomposition onset temperature was 480°C, but the highest char yield of 60% was obtained. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1387–1392, 2000     

钇三元配合物的合成、表征及其抗菌活性研究

以YCl3.6H2O、2,6-吡啶二羧酸(PDA)和噻吩甲酰三氟丙酮(TTA)为原料,制备了钇的三元配合物,用元素分析、红外光谱、X射线光电子能谱对配合物进行了表征,确定了配合物的化学组成为:Na[Y(TTA)2(PDA)].3H2O(反应时间为1 h)和Na2[Y(TTA)3(PDA)].3H2O(反应时间为0.5 h)。抗菌实验表明,Na[Y(TTA)2(PDA)].3H2O对大肠杆菌和金黄色葡萄球菌的抑菌圈直径分别约为14,12 mm,Na2[Y(TTA)3(PDA)].3H2O分别约为16,14 mm,说明配合物对大肠杆菌、金黄色葡萄球菌具有一定的抑制作用,且对大肠杆菌的抑制效果较好。     

Synthesis and properties of new aromatic copolyesters containing phosphorous cyclic bulky groups

A series of phosphorus‐containing copolyesters was prepared by polycondensation of 2‐(6‐oxido‐6H‐dibenz<c,e><1,2>oxaphosphorin‐6‐yl)‐1,4‐naphthalene diol, 1 , or of an equimolecular amount of 1 and different bisphenols 2 , such as 4,4′‐isopropylidenediphenol, 4,4′‐(hexafluoroisopropylidene)diphenol and 2,7‐dihydroxynaphthalene, with an aromatic diacid chloride containing two preformed ester groups 3 , namely, terephthaloyl‐bis‐(4‐oxybenzoyl‐chloride). The copolyesters exhibited good thermal stability having the temperature of 5% weight loss above 380°C and char yield at 700°C in the range of 20–31.2%. The glass transition temperature was in the range of 136–147°C. The polymers exhibited thermotropic liquid crystalline behavior, as was observed with polarized optical microscopy, differential scanning calorimetry, and X‐ray experiments. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers     

Synthesis,structures and catalytic activities of half-sandwich ruthenium complexes based on Schiff Base ligands

A series of half-sandwich ruthenium(II) complexes containing Schiff-base ligands [Ru(p-cymene)LCl] [HL = (E)-4-X-2-((phenylimino)methyl)phenol, X = H (2a); X = CH₃ (2b); X = Cl (2c) and X = Br (2d)] have been synthesized and fully characterized by ¹H and ¹³C NMR spectra, elemental analyses and infrared spectrometry. Moreover, the molecular structures of ruthenium complexes 2b and 2c were confirmed by single-crystal X-ray diffraction methods. These half-sandwich ruthenium complexes are highly catalyzed hydrogenation of nitroarenes to aromatic anilines to proceed in the presence of sodium borohydride reducing agent in ethanol solvent. Notably, complex 2c was found to be a very efficient catalyst toward reduction of nitroarene compounds with wide functional group compatibility and substrate scope.     

钇/羟基磷灰石的制备及对含磷废水的净化

以氢氧化钙和磷酸二氢钠为原料制备羟基磷灰石,通过化学沉淀法制备钇/羟基磷灰石复合材料,利用SEM-EDS（扫描电子显微镜）、XRD（X射线衍射）、FTIR（傅里叶变换红外光谱）等表征其晶体结构与形貌,并采用静态吸附实验考察吸附剂的负载比例、pH、吸附时间和初始浓度对磷酸盐的吸附性能的影响。结果显示：羟基磷灰石为分散均匀的稻米状颗粒,XRD图谱显示为典型的羟基磷灰石,钇/羟基磷灰石颗粒发生团聚且粒径变大,特征峰峰强减弱,但未出现新的强特征峰。吸附研究表明：钙与钇的摩尔比为2∶1时吸附效率最高,复合材料的吸附容量随初始浓度的增加而增大,最大吸附量为116.38mg/g,吸附过程符合准二级动力学模型、双室一级动力学模型和Freundlich等温吸附模型,吸附过程由化学吸附主导,随pH在3~9的范围增加,复合材料的吸附效率先增后减,在pH为5~6时达到最大值。     

Living radical polymerization of styrene mediated by a piperidinyl-N-oxyl radical having very bulky substituents

A new cyclic nitroxide 1 and the corresponding alkoxyamines 9 and 10 were synthesized and the polymerization of styrene (St) initiated with 10 was investigated. The NO-C bond of 9 is very weak, cleaving at room temperature. On the other hand, alkoxyamine 10 is stable at room temperature and the A_act and E_act for the NO-C bond homolysis were determined to be 1.4 × 10¹⁵ s⁻¹ and 124.5 kJ mol⁻¹, respectively. When the polymerization of St was carried out at 70 °C, the resultant poly(St) showed narrow polydispersities below 1.25. In the polymerization at 90 °C, the resulting poly(St) showed narrow polydispersity until 60% conversion, but M_w/M_n was rapidly increased above 60% conversion. On the other hand, the polymerization at 120 °C gave poly(St) with broad polydispersities. The unusual polymerization behavior was discussed on the basis of the SEC and ESR results.     

Synthesis, electrochemical and spectroelectrochemical characterization of novel soluble phthalocyanines bearing chloro and quaternizable bulky substituents on peripheral positions

A new phthalonitrile derivative (2), bearing diethylaminophenoxy - and chloro-substituents at peripheral positions was synthesized in this work. Cyclotetramerization of (2) in hexanol gave the desired metal-free (4) and metallophthalocyanines (5-8). These new phthalocyanines (4-8) were converted into water-soluble quaternized products by the reaction with methyl iodide (9-11). The novel compounds have been characterized by using elemental analysis, UV-Vis, FT-IR, ¹H NMR and MS spectroscopic data. The aggregation behaviors of the phthalocyanine complexes were studied in different solvents and concentrations. Electrochemical and spectroelectrochemical characterization of the complexes were also performed in solution. Cobalt phthalocyanine gives both metal-based and ring-based reduction processes in comparison to the complexes having 2H⁺, Zn²⁺, Ni²⁺ and Cu²⁺ metal center which give only ring-based reduction processes. Electrochemical and spectroelectrochemical measurements exhibit that all complexes oxidatively electro-polymerize on the Pt working electrode during repetitive cyclic voltammetry measurements. An in-situ electrocolorimetric method was applied to investigate the color of the electrogenerated anionic and cationic forms of the complexes for possible electrochromatic applications.