光敏感遥爪聚合物C-PDMAEMA的合成及其性能研究

以香豆素二硫化物(C-S-S-C)/三丁基膦复合体系为链转移剂、甲基丙烯酸-N,N-二甲氨基乙酯(DMAEMA)为单体、偶氮二异丁腈(AIBN)为引发剂制备了末端为香豆素光响应基元的双亲性遥爪聚合物(C-PDMAEMA). 用FTIR, GPC, ¹H NMR等对该聚合物进行了结构表征. 研究表明该遥爪聚合物可直接在水中形成纳米聚集体|且其香豆素端基可在365 和254 nm交替光照下进行可逆光二聚反应. 同时纳米粒度跟踪(Malvern Zetasizer Nano-ZS)、透射电镜(TEM)跟踪结果表明, 随香豆素端基光二聚反应的进行, 聚合物纳米聚集体的粒径逐渐增大|反之, 随着光解二聚反应的进行, 该纳米聚集体的粒径逐渐减小.     

双亲性光敏感遥爪聚合物C-PNIPAAm的合成与性能

以7-羟基-4-甲基香豆素为原料,依次与环氧氯丙烷、二硫化钠反应得一含香豆素基元的二硫化物(C-S-S-C),并以其与三丁基膦复合体系为链转移剂,偶氮二异丁腈(AIBN)为引发剂,N-异丙基丙烯酰胺(NIPAAm)为单体制备了末端为香豆素光响应基元的双亲性遥爪聚合物(C-PNIPAAm).用傅里叶变换红外(FT-IR)光谱、凝胶渗透色谱(GPC)、氢核磁共振(1H-NMR)等对该聚合物进行了结构表征.研究显示该双亲性遥爪聚合物可在水中直接形成胶束,并以荧光素为疏水性客体考察了聚合物胶束的光控释放行为.在波长大于310 nm的紫外光照射下,聚合物链末端的香豆素单元可进行光二聚,胶束结构随之改变,因而所负载的荧光素可得到逐步有效释放.动态激光光散射(DLS)检测显示,光二聚反应使聚合物胶束平均粒径从56.6 nm增大至101.0 nm.     

NMP与ROP相结合制备PCL-b-PSt共聚物及其性能研究

以4-羟基-2,2,6,6-四甲基哌啶氮氧自由基（HTEMPO）为引发剂,通过ε-己内酯（ε-CL）的开环聚合,合成末端基为氮氧自由基的聚己内酯（PCL-T）。在其调控下,进行过氧化苯甲酰（BPO）引发苯乙烯（St）的自由基聚合,合成结构规整的聚己内酯-b-聚苯乙烯（PCL-b-PSt）共聚物。用氢核磁共振（1H-NM...     

新型O-取代苯磺酰羟胺化合物的合成及其热性能

以O-取代苯磺酰氯和乙酰羟肟酸乙酯为原料，经消除、水解反应合成了6个新型的O-取代苯磺酰羟胺化合物：O-2-硝基苯磺酰羟胺、O-3-硝基苯磺酰羟胺、O-2,4-二硝基苯磺酰羟胺、O-2,4-二甲基苯磺酰羟胺、O-2,4,6-三甲基苯磺酰羟胺和O-2,4,6-三异丙基苯磺酰羟胺，其结构经¹H NMR, ¹³C NMR, IR和元素分析表征。并初步探讨了可能的反应机理。利用差示扫描量热分析(DSC)研究了化合物的热性能。结果表明：苯环上取代基供电子能力越强，化合物的热稳定性越好。     

Synthesis and Thermal Properties of a Novel Nitrogen-containing Epoxy Resin

A new nitrogen-containing epoxy resin (XT resin) was synthesized from chain extension of xylenephenolformaldehYlde resin (XPF) and triglycidyl isocyanurate (TGIC) in the presence of base catalyst. FT-IR and H-NMR analysis confirmed the chemical structure of XT resin. It was cured with dicyandiamide (DICY) and diaminodiphenyl sulfone (DDS). Dynamic mechanical analysis (DMA) results showed that the introduction of triazine ring provides epoxy polymer with good thermal stability. Furthermore, high char yields at 800℃ in thermogravimetric (TGA)analysis indicated that XT resin had potential flame retardance.     

Novel Silsesquioxane-Derived Boronate Esters—Synthesis and Thermal Properties

The functionalization of mono- and octahydrospherosilicate with vinylboranes and allylboranes via hydrosilylation reaction in the presence of a Karstedt’s platinum (0) catalyst is presented. This is the catalytic route to obtain a new class of silsesquioxanes containing boron atoms in their structure in high yields (>90%) and with satisfactory selectivity. The obtained compounds were fully characterized by spectroscopic (¹H, ¹³C, ²⁹Si NMR) and spectrometric methods (MALDI-TOF-MS), as well as thermal analysis (TGA). The obtained compounds were subjected to thermal tests, characterizing the processes of melting, thermal evaporation, sublimation and thermal decomposition.     

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.     

甲醇热还原法制备高分散Cu2O微米立方体及其光催化性能

通过简单的甲醇热还原法制备高分散Cu2O微米立方体,制备过程中无需添加表面活性剂。利用X射线衍射(XRD)、场发射扫描电镜(FESEM)、高分辨透射电镜(HRTEM)、X射线光电子能谱(XPS)等分析测试手段对样品的物相及形貌进行表征;通过紫外可见漫反射(UV-Vis)及光致发光光谱(PL)对样品的光化学性能进行表征;样品的光催化性能通过可见光(λ>400 nm)催化降解罗丹明B染料(RhB)脱色活性进行测试表征。同时,对样品光催化性能与物理化学性能之间的内在联系进行了研究。结果表明:制备温度对样品的形态及光催化性能有着重要影响,当制备温度为140℃时,可制备得到高分散Cu2O微立方体并且其显示出最优的光催化活性;当制备温度进一步提高时,得到的样品为超细铜粉,样品的光催化性能迅速降低。     

Thermal Properties and Morphology of Poly(Ester-Urethanes) Prepared from Polycaprolactone-Diol

The soft segment crystallinity and morphology of poly(ester-urethanes) (PEUs) based on poly(ε-caprolactone) (PCL) as a soft segment and an aliphatic diisocyanate in the hard segment were studied. It was found that the restriction of the crystallization of the PCL soft segment depends on the hard segment concentration, the length of the soft segment, and the total molecular mass of the PEUs. The PEU based on a low molecular mass PCL (M=2000) is an amorphous elastic material during a long time after casting from solution or after melt crystallization. A soft-hard segment endothermal mixing transition (T_mix) of about 70-80°C is observed in the DSC curves of this PEU sample. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis and Electroconductive Properties of Radical Salts Derived from Tetrathiafulvalene Dimers

Palladium(II)- or copper(II)-catalyzed homo-coupling reaction of either trimethylstannyltetrathiafulvalene or tetrathiafulvalenylzinc chloride produces symmetrical bitetrathiafulvalenes (bi-TTFs) in good yields, whereas palladium(0)-catalyzed cross-coupling reaction of tetrathiafulvalenylzinc chloride with 4-iodotetrathiafulvalenes leads to the corresponding unsymmetrically substituted bi-TTFs in moderate-to-high yields. The X-ray analysis of bi-TTF derivatives showed planar structures, and the cyclic voltammetry suggested that bi-TTFs have good donor ability comparable to that of BEDT-TTF. The symmetrical bi-TTFs formed the corresponding CT-complexes and cation radical salts. These CT-complexes and radical salts were found to be metallic or semiconducting, reflecting the effect of stoichiometry control in the dimeric TTF system. The X-ray structures of two cation radical salts revealed a unique stacking, and the precise conducting path in BEDO-bi-TTF·ClO₄ was discussed on the basis of MO calculations.     

Synthesis,Structure and Magnetic Properties of a Novel Nickel(II) Radical Heterospin Complex with Salicylaldoxime

A novel heterospin complex containing both Ni^II and nitroxide radical ligands: [Ni(salox)₂(NIT4Py)₂] ( 1 ) (salox = salicylaldoxime, NIT4Py = 2‐(4′‐pyridyl)‐4,4,5,5‐ tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide) has been synthesized and structurally characterized. The structure consists of neutral Ni(salox)₂(NIT4Py)₂ moieties bridged by intermolecular hydrogen bonds, forming a one‐dimensional chain structure. Magnetic measurements show intramolecular antiferromagnetic interactions between NIT4Py and Ni²⁺ ion.     

基于氮氧自由基的新型稀土配合物的合成、结构及光谱性质

合成了一种新型的氮氧自由基-稀土配合物[Dy（hfac）3（H2O）2]·（NITMePy）(1, CCDC:846691, hfac=六氟乙酰丙酮,NITMePy=2-（2-吡啶基-3-甲基）-4,4,5,5-四甲基氧化咪唑啉-3氧化-1-氧基自由基),其结构和光谱性质经元素分析、红外光谱和紫外光谱表征。结果表明：配...     

Living Carbocationic Polymerization. LIX. The Synthesis of Novel Asymmetric Telechelic Polyisobutylenes

Abstract

The synthesis of novel asymmetric telechelic polyisobutylenes (PIB) carrying a CH₃OCO— headgroup and a —CH₂C(CH₃)₂C1 tailgroup by the use of novel initiators mediating the living carbocationic polymerization (LC⁺Pzn) of isobutylene (IB) is described. Subsequently, the parent headgroup has been quantitatively converted into a HOCO— group, and the parent tailgroup into a —pC₆H₄OH group. Scheme 1 summarizes the synthesis routes to the initiators, as well as the polymerizations and functionalizations leading to various asymmetric telechelic PIBs. The CH₃OCO— headgroup of the initiator most likely functions as an internal electron donor during the LC⁺Pzn of IB.     

Synthesis of Diester Disulfimides from Saccharinmonocarboxylic Acids and Aromatic Diols

The reactions of saccharinmonocarboxylic acids with bisphenol acetates and of saccharinmono-carboxylic acid chlorides with bisphenols yielded the corresponding diester disulfimides.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 444–446.Original Russian Text Copyright © 2005 by Aslanov, Mamedli, Guliev.     

Synthesis and Properties of Novel Hydrogels from Cross-linked Starch Phosphates

Summary: Starch based stable hydrogels providing high swelling and water storing capacity are not only of certain interest for the cosmetics and hygiene industry but also have the potential to become an effective tool in combating desertification and supporting cultivation in many regions of the world. It has been found that strong water adsorbing covalent networks with free swelling capacity (FSC) of up to 190 g water/g hydrogel can be obtained by cross-linking low-substituted mono-starch phosphates (MSP) in a semi-dry process with di- and tricarboxylic acids such as succinic acid (SA), adipic acid (AA) or citric acid (CA). The linear behaviour over a wide frequency range of the rheological parameters G′ and G″ which were determined by using a shearing disc viscosimeter clearly reveal that the cross-linked starch phosphates are stable hydrogels having stronger elastic than viscous properties.     

新型蒽类聚方酸菁的合成及其性能

以蒽为起始原料,经溴代反应和Witting-Horner反应制得单体9,10-双[2-(1-辛基-1H-吡咯-2-基)乙烯基]蒽(3);3与芳酸缩聚合成了一个新型的蒽类聚方酸菁(4),其结构和性能经UV-Vis,1HNMR,13CNMR,IR,XRD,SEM和TG表征。4在氯仿中的λmax位于700nm;4为非晶态结构;4的初始分解温度为297.1℃。     

Evaluation of Thermal Properties of Composites Prepared from Pistachio Shell Particles Treated Chemically and Polypropylene

The purpose of the present work was to prepare polypropylene (PP) matrix composited filled with chemically treated pistachio shell particles (PTx), and evaluate their effect on the composites’ thermal properties. PP-PTx composites were formulated in different PTx content (from 2 to 10 phr) in a mixing chamber, using the melt-mixing process. The PTx were chemically treated using a NaOH solution and infrared spectroscopy (FTIR). According to thermogravimetric analysis (TGA), the treatment of pistachio shell particles resulted in the remotion of lignin and hemicellulose. The thermal stability was evaluated by means of TGA, where the presence of PTx in composites showed a positive effect compared with PP pristine. Thermal properties such as crystallization temperature (Tc), crystallization enthalpy (∆Hc), melting temperature (Tm) and crystallinity were determinate by means differential scanning calorimetry (DSC); these results suggest that the PTx had a nucleation effect on the PP matrix, increasing their crystallinity. Dynamic mechanical analysis (DMA) showed that stiffness of the composites increase compared with that PP pristine, as well as the storage modulus, and the best results were found at a PTx concentration of 4 phr. At higher concentrations, the positive effect decreased; however, they were better than the reference PP.