带端烯基偶氮苯液晶化合物的合成和表征

合成了一种新的带端烯基偶氮苯类液晶化合物（ＡｚｏＣ５Ｃ６），用元素分析、紫外光谱、红外光谱和核磁共振光谱等进行了表征。     

含偶氮苯结构树枝状化合物的合成与表征

以间二苯甲酸为原料,经多步反应合成5-[4-（羟乙氧基苯基）偶氮]-1,3-苯二甲酸;进一步与均苯三甲酰氯反应得到新型含偶氮苯结构树枝状化合物,通过FT—IR、UV—vis和。HNMR对中间体及树枝状产物进行了结构表征。TGA分析显示,5％失重温度为225℃,DSC测得树枝状化合物的玻璃化转变温度（嗜）为95．7℃。     

新型苯酯苯类液晶化合物的合成与表征

以酒石酸为中心合成一种苯酯苯类高分子液晶化合物,2,3-二烯丙氧基苯甲酰氧基丁二酸对乙氧基苯甲酸对苯二酚酯(M1)。采用红外光谱仪(FT-IR)、差示扫描量热仪(DSC)、及偏光显微镜(POM)等技术进行了结构表征。实验结果表明,单体M1为热致互变向列液晶,升温过程和降温过程中均呈现纹影织构,相转变是可逆的。     

过渡金属偶氮化合物的合成与表征

合成和研究了两种新型的过渡金属偶氮化合物，利用红外光谱和紫外光谱对它们进行了初步的结构表征，结果表明金属离子已成功地连接在偶氮分子上。     

一种末端双炔类偶氮苯化合物的合成与表征

采用偶氮偶联、金属钯催化偶联法和Williamson醚合成法,合成了一种末端双炔类偶氮化合物,其结构经IR、1H NMR、DSC分析表征.     

含偶氮苯(喹啉)结构化合物的合成、表征及发光性能

以间苯二甲酸为原料,合成了新型偶氮苯-喹啉化合物—5-(8-羟基喹啉-5-偶氮)-1,3-苯二甲酸二乙酯,通过IR、UV-vis、1H NMR对其结构和性能进行了表征,利用荧光发射光谱研究了目标化合物的发光性能。结果表明,目标化合物(2.0×10-5 mol/L的THF溶液)以311 nm光激发,在450 nm处发射蓝紫色荧光。     

末端叠氮基偶氮苯化合物的制备及液晶性质表征

通过对偶氮苯原料化合物的修饰最终制备得到末端带叠氮基偶氮苯化合物,所得目标产物经1HNMR、13CNMR、FT-IR和元素分析确证化学结构。利用示差扫描量热法(DSC)及偏光显微镜(POM)研究其相转变行为,结果表明,目标产物在升温39.2～69.7℃以及降温65.7～14.3℃范围内具有液晶性质,而4,4’-二(6-叠氮己氧酰基)偶氮苯无液晶性质。     

一种新的双液晶基元化合物的合成与表征

合成了一种新的胆固醇酯基双液晶基元化合物,另一端液晶基元为4-苯甲酸(4′-甲氧基苯基)酯基,2个液晶基元通过丁二酸酯键相连。该双液晶基元化合物在加热和冷却过程中都在较宽的温度范围内出现胆甾相液晶,并随着温度的变化呈现鲜艳的颜色变化(170~227℃或222~87℃)。这种液晶化合物可能在液晶显示、铁电性或反铁电性液晶器件上有一定的应用前景。     

烷氧基偶氮萘化合物的合成表征及光响应性能

以间苯二甲酸为原料,经多步反应合成了一种新型烷氧基偶氮萘化合物5-[4-（十六烷氧基）-1-萘基偶氮]-1,3-苯二甲酸二乙酯。用FT-IR、1H NMR对其结构进行了表征。该化合物（3.24×10-5 mol/L四氢呋喃溶液）紫外光谱K带的最大吸收波长为406 nm,摩尔吸光系数ε为18 437 L/（mol﹒cm）。在365 nm紫外光照射下,该化合物发生反-顺异构化,光照6 min后达到光稳态,K带最大吸收波长蓝移至403 nm,将其置于暗室中,48 h后恢复到光照前状态。光稳态时偶氮发色团反-顺异构化转化效率R为42.4%,顺式异构体的比例Y为44.5%。     

离子液晶中间体4,4′-二羟基偶氮苯的合成及表征

以对氨基苯酚与盐酸反应合成氯化重氮盐,再将氯化重氮盐滴入苯酚水溶液中,通过偶合反应合成4,4′-二羟基偶氮苯,并通过重结晶和柱层析等手段对化合物进行纯化和结构表征,并摸索合成的最佳实验条件,提高产率,该物质是合成偶氮型离子液晶化合物的重要中间体。     

双氰乙基偶氮化合物的合成及表征

用无水AlCl3催化问甲苯胺与丙烯腈的加成反应,合成了偶合组分N,N-二氰乙基间甲苯胺,并分别与重氮组分对硝基苯胺、对硝基邻氯苯胺、2,4-二硝基-6-氯苯胺和2,4-二硝基-6-溴苯胺进行偶合反应,合成了4种双氰乙基偶氮化合物.结果表明,生成的偶氮化合物产率分别为72%、78%、91%和81%,含量均超过96%;而且...     

新型硅碳烷液晶树状物的合成与表征--端基含12个己氧基偶氮苯介晶基元

以基于季戊四醇-四烯丙基醚的硅氢化产物PCSi-1G-C1为脚手架、4-己氧基-4′-羟己氧基偶氮苯(M-C6)为介晶基元,合成了季戊四醇为核、端基含12个己氧基偶氮苯的新型硅碳烷液晶树状物PCSi-1G-C6.利用元素分析、傅立叶变换红外光谱(FT-IR)、核磁共振(NMR)、偏光显微镜(POM)和差示扫描量热(DSC)进行了表征.PCSi-1G-C6与M-C6同为相列相,树状物相态由介晶基元相态决定.PCSi-1G-C6的熔点比M-C6低50℃,清亮点比M-C6低16℃,液晶态温区比M-C6宽34℃.     

含有偶氮-亚胺基与胆固醇基双液晶基元化合物的合成与表征

合成了一种新型双液晶基元化合物,其含有胆固醇脂液晶基元和偶氮-亚胺连接的三苯环液晶基团,两个液晶基元通过丁二酸脂键相连.对产物的液晶性能进行了表征.该液晶化合物在加热过程(152～305℃)中很宽的温度范围内呈现典型的胆甾相液晶油丝织构,可能被用于信息存储、光转换开关以及非线性光学等领域.     

Synthesis and characterization of high molecular weight side chain liquid crystalline/photoactive polymers

Various liquid crystalline and photoactive azobenzene monomers were synthesized and attached to copoly(methyl methacrylate‐glycidyl methacrylate) [copoly (MMA‐GMA)] to get high molecular weight side chain liquid crystalline (LC)/photoactive copolymers. Further, spacers are generated in situ and reactive groups are obtained after the modification. All monomers and polymers were thoroughly characterized by FTIR, ¹H and ¹³C NMR, UV‐VIS spectrophotometry, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, and polarized optical microscopy. All side chain LC polymers showed higher thermal stability than that of copoly(MMA‐GMA). Three LC and one azo monomer exhibited characteristic nematic mesophase where as one LC monomer has shown nematic and sanded smectic‐A texture. The rate of trans‐cis isomerization of polymer was lower than that of the monomer and both monomers and polymers showed slow back isomerization. Present approach offers convenient way to synthesize high/desired molecular weight photoactive LC polymers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and characterization of side‐chain liquid‐crystalline polyacrylates containing azobenzene moieties

Syntheses of novel liquid‐crystalline polymers containing azobenzene moieties were performed by a convenient route with an acrylate backbone. The azobenzenes were key intermediates of the monomers, and side‐chain liquid‐crystalline polymers were prepared, that is, poly[α‐{4‐[(4‐acetylphenyl)azo]phenoxy}alkyloxy]acrylates, for which the spacer length was 3 or 11 methylene units. In addition, poly[3‐{4‐[(3,5‐dimethylphenyl)azo]phenoxy}propyloxy]acrylate was prepared with a spacer length of 3 methylene units. The structures of the precursors, monomers, and polymers were characterized with Fourier transform infrared, ¹H‐NMR, and ¹³C‐NMR techniques. The polymers were obtained by conventional free‐radical polymerization with 2,2′‐azobisisobutyronitrile as an initiator. The phase‐transition temperatures of the polymers were studied with differential scanning calorimetry, and the phase structures were evaluated with a polarizing optical microscopy technique. The results showed that two of the monomers and their corresponding polymers exhibited nematic liquid‐crystalline behavior, and one of the monomers and its corresponding polymer showed smectic liquid‐crystalline behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2653–2661, 2002     

Synthesis and characterization of sulfonated liquid crystalline polyesters

Liquid crystalline polyesters based on hexanediol, dimethyl 4,4′‐biphenyldicarboxylate, and various levels of dimethyl 5‐sodiosulfoisophthalate (0–20 mol%) were prepared using a conventional melt polymerization process. The presence and quantification of the ionic functionality was surveyed using ¹H NMR spectroscopy. Solution viscosities and corresponding molecular weights decreased when the ionic monomer concentration exceeded a critical value (higher than 3 mol%). Differential scanning calorimetry indicated a maximum in the isotropic transition temperature versus ionic modification at approximately 10 mol%. Dynamic mechanical analysis indicated that the glass transition temperature was suppressed due to ionic association at high concentrations (greater than 3 mol%) of ionic functionality. Polarized light microscopy and wide‐angle X‐ray diffraction were used to identify the smectic liquid crystalline and crystalline phases. © 2002 Society of Chemical Industry     

新型树枝状硅碳烷液晶大分子的合成与表征

以肌醇为核心 ,经烯丙基醚化、多步硅氢化加成反应和Grignard反应合成了树枝状大分子 3G -Cl,然后和偶氮苯介晶基元反应制备了新型树枝状硅碳烷液晶 ,用元素分析、核磁共振谱、激光飞行质谱对其进行了结构表征 ,偏光显微照片和差示扫描量热表明 ,其液晶相为向列型N相     

Synthesis and chiroptical properties of liquid crystalline copolymers containing azobenzene chromophores

A series of new liquid crystalline copolymers, poly[((S)‐2‐methyl‐1‐butyl methacrylate)‐co‐(6‐(4‐(4‐cyanophenylazo)phenoxy)hexyl methacrylate)], with different contents of chiral units of 17, 36, 54 and 78 mol% were synthesized. The structures and properties of the copolymers were characterized and evaluated using infrared, ¹H NMR and UV spectroscopy, differential scanning calorimetry, gel permeation chromatography and circular dichroism (CD). The CD results suggested that absorptions of azobenzene chromophores were observed in films of copolymer containing 17, 36 or 54 mol% chiral units, but not in the film of copolymer containing 78 mol% chiral units. Also, CD values of the copolymeric films decreased with increasing chiral content. After irradiation with linear polarized light at 442 nm, CD values were changed in all the copolymeric films, and the CD values increased with decreasing chiral content in a nonlinear way, while the photoinduced change of chirality of the copolymers increased in a linear way with decreasing chiral content. The results are discussed in terms of interactions between structures and chiroptical properties. Copyright © 2007 Society of Chemical Industry     

Synthesis and characterization of a new discotic columnar side-chain liquid crystalline polymer deuterated for NMR analysis

As part of our attempt to prepare molecular spinning machine, we synthesized a new discotic liquid crystalline polymethacrylate based on the taper-shaped monoester of triethylene glycol with 3,4,5-tris(p-dodecyloxylbenzyloxy-m-methoxybenzyloxy)benzoic acid. The polymethacrylate was deuterated in the benzoic ring for subsequent solid-echo ²H NMR spectroscopy. The m-methoxy group was proposed to prevent the rotation of the benzene ring, thereby inducing the cooperative rotational motion of the polymer.     

Synthesis and properties of lyotropic liquid crystalline copolyamides containing phthalazinone moiety and ether linkages

A series of aromatic copolyamides containing phthalazinone moiety and ether linkages were prepared from 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-(aminophenoxyl)phenyl)](2H)phthalazin-1-one (DHPZ-DA), p-phenylenediamine (PPD), 4,4′-diaminodiphenylether (DAPE) and terephthaloyl dichloride (TPC) by low temperature solution polycondensation. The copolyamides had relatively high inherent viscosities, ranging from 1.86 to 5.30 dl/g. The copolyamides showed T_g values between 297 and 351 °C. Solubility of these copolyamides was improved in NMP, DMAc, NMP (1 wt% LiCl) and DMAc (1 wt% LiCl) by introducing phthalazinone moiety and ether linkages into the main chain. And they had good thermal stability, associated with 5 and 10% weight loss temperatures in the range of 480-516 and 501-532 °C in nitrogen, respectively. WAXD measures indicated these copolyamides were semicrystalline in nature. Some of these copolyamides exhibited lyotropic liquid crystalline behavior in concentrated H₂SO₄, NMP (1 wt% LiCl), and even in NMP solutions, as evidenced by polarizing light microscopy.