基于氨基偶氮苯的光和pH响应聚[（三甲基丙烯酸乙酯胺）8-（4-氨基-4’-甲基丙烯酰胺基偶氮苯）1]（T8A1）的合成与表征

以对硝基苯胺为原料,经过偶联、还原和酰化反应,合成了4-氨基-4’-甲基丙烯酰胺基偶氮苯(AMAB);将三乙醇胺和甲基丙烯酰氯反应制得水溶性的十字交联剂三甲基丙烯酸乙酯胺(TMAEA);将AMAB和TMAEA进行自由基沉淀聚合反应,制得基于氨基偶氮苯的新型纳米级聚合物——聚[(三甲基丙烯酸乙酯胺)8-(4-氨基-4’-甲基丙烯酰胺基偶氮苯)1](T8A1),并用紫外-可见光谱(UV-Vis)、红外光谱(IR)、热失重(TG)和扫描电子显微镜(SEM)对T8A1进行了表征.结果表明,T8A1在水中具有光和pH双重响应性能,弥补了传统的偶氮苯类材料仅能在有机溶剂中具有响应的缺陷,具有广阔的仿生应用前景.     

含偶氮苯基元联酰胺衍生物的有机凝胶和光响应性质

设计合成了具有不同末端烷基链长度的偶氮苯类联酰胺衍生物N-(3,4-n-氧基苯基)-N'-4-(偶氮苯基)苯甲酰肼(Dn,n=7,8,10).Dn可以形成稳定的有机凝胶,末端烷基链增加有利于提高凝胶能力和热力学稳定性.凝胶形成的驱动力主要为联酰胺基团间的分子间氢键以及偶氮苯基团间的π-π相互作用和烷基链间的范德华力.在紫外光照射下,Dn中的反式偶氮苯向顺式转化,并且在溶液中的光响应性非常显著,但凝胶态下偶氮苯的光致顺反异构不能诱导凝胶-溶胶的转变.     

偶氮苯侧链共聚硅氧烷的合成及液晶行为的研究

以苯酚、十一烯酸、正溴己烷、对硝基苯酚和二氯亚砜为主要原料 ,通过取代、还原、重氮化和偶合等反应 ,合成了一种新的液晶单体 4 己氧基 4′ 十一烯 [1 0 ] 酰氧基偶氮苯 ,并与聚 (甲基氢硅氧烷 )通过硅氢加成生成一种新的高分子液晶 .通过1 H NMR和IR对单体和聚合物的结构进行了表征 ,并证实了聚合物的硅氢化程度近于完全 .通过DSC和热台偏光显微镜 (POM)对单体和聚合物的液晶行为进行了研究 ,证明了都具有液晶性     

基于原子转移自由基聚合技术的偶氮苯星形液晶聚合物的合成与表征

利用原子转移自由基聚合(ATRP)技术合成了含不同端基取代基的偶氮苯三臂星形侧链液晶聚合物. 均苯三酚与2-溴异丁酰溴通过酯化反应制备三官能团引发剂, 引发偶氮苯单体6-[4-(4-甲氧基苯基偶氮)酚氧基]己基甲基丙烯酸酯(MMAzo)或6-[4-(4-乙氧基苯基偶氮)酚氧基]己基甲基丙烯酸酯(EMAzo)的ATRP反应. 利用核磁共振氢谱(¹H NMR)、凝胶色谱(GPC)、差示扫描量热法(DSC)和偏光显微镜(POM)等手段对星形聚合物进行表征. 星形聚合物的液晶性与相应均聚物相似, 但偶氮苯端基取代基的不同导致星形聚合物的液晶性差别显著. 在紫外/可见光照射下星形聚合物呈现明显的异构化转变.     

结肠定位给药系统载体偶氮聚合物合成-对甲基丙烯酰胺偶氮苯的合成与表征

为了设计与合成新的结肠靶向给药系统载体-三元偶氮共聚物，提出合成一种新的偶氮功能单体—对甲基丙烯酰胺偶氮苯[Bis(methacryloylamino)-azobengene，BMAAB]作为偶氮聚合物交联剂。BMAAB合成方法：先将对硝基苯胺氧化偶联，再还原成对胺基偶氮苯(DAXB)，最后再与甲基丙烯酰氯反应。用紫外、红外、核磁共振与差热分析对产物进行了表征。     

偶氮苯功能化两亲性共聚物的合成与其纳米聚集体光响应行为的研究

以4,4'-二羟乙氧基偶氮苯(BHEAZO)为引发剂引发对二氧环己酮(PDO)开环聚合,与羧基化的单羟甲基聚乙二醇(mPEG)偶联,制备了具有光响应性的两亲性三嵌段共聚物mPEG-BHEAZO-PPDO-mPEG,并对其纳米聚集体的光响应行为进行了研究.采用紫外可见光谱(UV-Vis Spectroscopy)研究了纳米聚集体水溶液的吸光度随着光照时间的变化;用动态光散射(DLS)研究了辐射波长对纳米聚集体的粒径及粒径分布的影响;结合透射电子显微镜(TEM)的研究结果,提出了对纳米聚集体在不同波长光照下聚集行为改变的机理,即反式结构共平面的共轭体系更易形成稳定的低能级电子离域状态,从而使得纳米聚集体之间通过π-π堆积作用形成微聚集现象.     

侧基含羟基的主链偶氮苯液晶共聚酯的合成及其光响应行为

以4,4’-双(6-羟基己氧基)联苯(BHHBP)、4,4’-双(6-羟基己氧基)偶氮苯(BHHAB)为液晶基元,利用苹果酸二乙酯(DM)和苯基丁二酸(PSA)采用无规共聚,合成了侧基含羟基的偶氮苯液晶共聚酯(Az-LCP).先在液晶态下拉伸取向,然后用六亚甲基二异氰酸酯(HDI)交联制备单畴取向偶氮苯液晶交联网络.通过核磁共振氢谱(1H-NMR)、凝胶渗透色谱(GPC)测试,对合成的Az-LCP进行结构表征,通过示差扫描量热分析(DSC)、X射线衍射(XRD)、偏光光学显微镜(POM)等对其液晶相变行为进行表征,研究了偶氮苯含量、交联密度、薄膜厚度对其光致弯曲行为的影响.结果表明,偶氮苯含量10%,交联12 h的Az-LCP1具有最佳的光致弯曲回复行为.     

新型弯曲形双偶氮苯类液晶合成及光致异构性能研究

弯曲形偶氮苯液晶由于其偶氮键独特的光致可逆异构化性能,已成为光电子信息材料研究的热门课题,但光响应速度慢已成为制约其发展的关键因素.目前报道的弯曲型偶氮类液晶化合物的偶氮键都距离中心核较远的位置,光致异构的响应时间较长,大都在分钟以上,不利于光敏器件应用研究.本工作试图以2-甲基-1,3-间苯二胺为中心核,将偶氮键紧挨中心核两边,末端为直链烷基,设计合成了一系列新型弯曲形双偶氮苯类液晶化合物,以期缩短光响应时间.通过IR, 1H NMR, 13C NMR和ICP-MS光谱鉴定这些化合物的分子结构,经差示扫描量热仪(DSC)和偏光显微镜(POM)测定其液晶相变温度和相态织构;并通过测定2-甲基-1,3-双(4-((4-庚基苯基)酯基)-1-(E)-偶氮苯基)苯(2c)的紫外-可见光的吸收光谱研究其光致异构化性能,通过UV-Vis光谱仪和偏光显微镜(POM)测定其液晶化合物以及掺杂向列相液晶材料的光致异构现象和响应时间.实验结果表明,所有设计合成的弯曲形双偶氮苯类液晶化合物均具有近晶相相态,且相态温度范围较宽,当近晶相态化合物2c掺杂到向列相混合液晶中时,其光致异构响应时间为2~3 s,在日光下液晶态恢复时间为3~4s,在乙酸乙酯稀溶液中时10s可达到光稳态.说明这类弯曲形双偶氮液晶化合物具有较快的光致异构响应速度.     

含偶氮苯侧链分子刷聚合物的合成及其光响应自组装

分子刷聚合物伸展的高分子主链、高密度的侧链和较低的侧链空间缠结,使其展现出独特的流变学、力学性能和特殊的分子聚集状态,在纳米技术、表面科学等领域有着广泛的应用前景.基于同时含有2-羰基溴与炔基基团的大分子试剂聚2-((2-溴代丙酰氧基)甲基)丙烯酸丙炔酯,引发偶氮苯丙烯酸酯单体的原子转移自由基聚合(ATRP)与叠氮功能化的巴比妥酸衍生物的点击反应,合成了新型含偶氮苯侧链的分子刷聚合物聚丙烯酸酯-g-聚(6-(4-丁基-4′-氧偶氮苯)正己基丙烯酸酯)/巴比妥酸(PA-g-PAzo/Bar),研究了其在溶液中的自组装和光响应性行为.随着分子刷聚合物浓度的增加,聚集体由柱状胶束向复合胶束转变.由于光响应性偶氮苯侧链的存在,在紫外光的照射下偶氮苯生色团发生trans-cis异构化转变,促使柱状胶束融合形成多孔网状聚集体,同时球形复合胶束融合形成珍珠项链状聚集体.     

含X-型二维液晶基元和顺式-4,4′-双(4-羟基苯基偶氮)二苯并-18-冠-6冠醚环液晶共聚酯的合成与表征

以4,4'-(α,ω-辛二酰氧)二苯甲酰氯(M1)、2,5-双[4-'(对癸氧基苯基)苯甲酰氧基]对苯二酚(M2)和顺式-4,4'-双(4-羟基苯基偶氮)二苯并-18-冠-6(M3)为单体,通过溶液共缩聚反应,合成了一系列新的含X-型二维液晶基元和顺式-4,4'-双(4-羟基苯基偶氮)二苯并-18-冠-6冠醚环的主链犁液晶共聚酯.单体1(M1)由对羟基苯甲酸和辛二酰氯,通过酯化和取代反应制备,单体2(M2)由2,5-二羟基苯醌和对癸氧基苯基苯甲酰氯通过酯化和还原反应制备,单体3(M3)由顺式-二氨基二苯并-18-冠-6和苯酚通过重氮化和偶联反应制备.共聚酯的分子量小高,[η]在0.30～0.39之间.单体的化学结构通过 IR、UV、1H-NMR、MS 和元素分析等方法确证.共聚酯的外观为黄色粉状固体,除共聚酯 CP9 外,室温下不溶于 CHCl3 和 THF 溶剂.共聚酯的性质采用 GPC、[η]、DSC、TG、WAXD 和 POM 等方法进行了研究.发现所有的共聚酯加热到各自的熔融温度以上都能形成液晶态,在液晶态可以观察到近晶相和向列相的典型织构.共聚酯的熔融温度(Tm)和各向同性温度(T1)随共聚酯分子中顺式-4,4'-双(4-羟基苯基偶氮)二苯并-18-冠-6用量的改变呈规律性变化.WAXD 研究进一步证实了共聚酯的液晶性.     

Synthesis and binding site characteristics of 2,4,6-trichlorophenol-imprinted polymers

2,4,6-Trichlorophenol (2,4,6-TCP)-imprinted micro- and submicrospheres prepared by precipitation polymerization were compared with templated materials obtained by conventional bulk polymerization. The influence of the type and amount of functional monomer, the type and amount of cross-linker, polymerization temperature, porogen, and the ratio of template molecule and functional monomer to cross-linker on the size of the obtained particles were investigated. UV-Vis spectrophotometer experiments revealed that the microsphere polymers provided higher affinity to the template in contrast to imprinted polymers prepared by bulk polymerization. The binding properties of the microspheres, including binding isotherms and affinity distribution, were studied via Freundlich isotherm affinity distribution (FIAD) analysis. The obtained results indicated that microspheres prepared by precipitation polymerization provided superior rebinding properties during equilibrium binding in contrast to bulk polymers and submicrosphere polymers. Moreover, release experiments showed that 80% of rebound 2,4,6-TCP was released from the imprinted microspheres within the first 2 h, while more intimately bound 2,4,6-TCP molecules were released in the following 40 h. The morphologies and porosities of the resulting imprinted materials were characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, respectively. The microsphere polymers exhibited a regular spherical shape with a high degree of monodispersity to the corresponding bulk polymers. Furthermore, the micro- and submicrospheres were characterized by narrow distribution of pores in contrast to a heterogeneity index of m = 0.6647 for the microsphere imprinted polymer.     

STUDY ON PHOTODYNAMIC AND PHOTORESPONSIVE AZO POLYELECTROLYTES*

Several kinds of novel azobenzene-containing polyelectrolytes with special molecular design have been developedfrom acryloyl chloride or epoxy based precursor polymers. The acryloyl chloride based precursor polymer, poly(acryloylchloride), was prepared by free radical polymerization of acryloyl chloride. The azo polyelectrolytes were prepared by anesterification reaction between the precursor polymer and corresponding azo chromophores containing a reactive hydroxylgroup, followed by hydrolysis of the unreacted acyl chloride groups. The epoxy based precursor polymer was prepared by thereaction between 1,4-cyclohexanedimethanol diglycidyl ether and aniline, and postfunctionalized by azo coupling reaction toform azo polymers containing chromophores with ionizable groups. The polyelectrolytes were characterized by elementalanalysis, ~1H-NMR, IR and UV-Vis spectroscopy. The photodynamic and photoresponsive properties, as well as self-assemblyof these azo polyelectrolytes are reported in this paperp.     

Preparation of a pH-sensitive pantoprazole-imprinted polymer and evaluation of its drug-binding and -releasing properties

The aim of this work was to synthesize a pantoprazole-imprinted polymer(MIPs)and study its binding and release properties in an aqueous media.Methacrylic acid(MAA),methacrylamide(MAAM),hydroxyethyl methacrylate(HEMA),and 4-vinyl pyridine(4VP)were tested as functional monomers.Different solvents were also applied as polymerization media under heat or UV radiation.The optimized MIP was prepared in chloroform as a solvent,4-vinyl pyridine as a functional monomer,and ethylene glycole dimethacrylate(EGDMA)as a crosslinker monomer under UV irradiation.Binding and release properties of MIP were studied in comparison with a non-imprinted polymer(NIP)in aqueous media,at different pH values.The protective effect of polymer for drugs against acidic conditions was evaluated at pH 2.Results indicated that the MIP had superior binding properties compared to NIP for pantoprazole.The percentage of drug released from MIP was significantly less than from NIP at all pH values,which was attributed to the presence of imprinted cavities in the MIP matrix.MIP also had a stronger protective effect for pantoprazole in acidic media,in comparison with NIP.     

光响应性有机-无机杂化分子印迹聚合物的制备及表征

以4-硝基苯酚、 2,4-二氯苯氧乙酸和3-氯丙基三乙氧基硅烷为原料, 经氧化偶合、 酰化、 酯化反应合成了共价结合模板分子2,4-二氯苯氧乙酸(2,4-D)的光响应性含有机硅的偶氮苯功能单体, 通过溶胶-凝胶法制备了光响应性的有机-无机杂化分子印迹聚合物(OIHMIP). 研究了该分子印迹聚合物光响应性能、 对2,4-D的吸附性能和选择识别及光控释放与吸收能力, 用原子力显微镜对其形貌进行了表征. 结果表明, 制得的OIHMIP具有规则的球形, 粒径介于150～200 nm之间. OIHMIP对2,4-D具有良好的吸附和选择识别能力, 在365和440 nm的紫外-可见光交替照射下, 可控制2,4-D的释放与吸收.     

Synthesis of a dipyrromethane functionalized monomer and optoelectrochromic properties of its polymer

A dipyrromethane functionalized monomer; 5-(4-tert-butylphenyl)dipyrromethane (BPDP) was synthesized. The structure of the monomer was characterized by nuclear magnetic resonance (¹H NMR and ¹³C NMR) and Fourier transform infrared (FTIR) spectroscopies. Electrochemical polymerization of BPDP was performed in acetonitrile (AN)/LiClO₄. The resulting conducting polymer was characterized by FTIR spectroscopy and electrical conductivity measurements. Spectroelectrochemical behavior and switching ability of P(BPDP) film were investigated by UV-Vis spectroscopy. P(BPDP) revealed color changes between yellow and blue in the reduced and oxidized states, respectively. In order to investigate electrochromic properties and stability of the P(BPDP) in electrochromic device (ECDs) application, dual type polymer ECD based on P(BPDP) and poly(ethylene dioxythiophene) (PEDOT) were constructed. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-Vis spectroscopy and cyclic voltammetry.     

Synthesis and characterization of photo‐responsive magnetic molecularly imprinted microspheres for the detection of sulfonamides in aqueous solution

A dual responsive molecularly imprinted polymer sensitive to both photonic and magnetic stimuli was successfully prepared for the detection of four sulfonamides in aqueous media. The photoresponsive magnetic molecularly imprinted polymer was prepared by surface imprinting polymerization using superparamagnetic Fe₃O₄ nanoparticles functionalized with a silica layer as a support, water‐soluble 4‐[(4‐methacryloyloxy)phenylazo]benzenesulfonic acid as the functional monomer, and sulfadiazine as the template. The magnetic molecularly imprinted polymers showed specific affinity to sulfadiazine and its structural analogs in aqueous media. Upon alternate irradiation at 365 and 440 nm, the quantitative bind and release of the four sulfonamides by magnetic molecularly imprinted polymers occurred. Furthermore, the prepared magnetic molecularly imprinted polymers were used as solid‐phase extraction material selectively extracted the four sulfonamides from water samples with good recoveries. Thus, a simple, convenient, and reliable detection method for sulfonamides in the environment based on responsive magnetic molecularly imprinted polymers was successfully established.     

沉淀聚合制备诺氟沙星-Zn2+分子印迹聚合物及其印迹方式的研究

采用沉淀聚合的方式以诺氟沙星(NFA)-Zn2+为模板分子,乙二醇二甲基丙烯酸酯为交联剂,分别选取酸性功能单体甲基丙烯酸与碱性功能单体4-乙烯基吡啶制备了诺氟沙星-Zn2+的分子印迹聚合物.通过紫外光谱研究发现诺氟沙星与Zn2+及两种功能单体均发生了金属配位印迹作用且形成了比例不同的印迹复合物.红外光谱的功能基团的表征结果显示,甲基丙烯酸与诺氟沙星-Zn2+形成了以诱导作用占优的三元配合物,而4-乙烯基吡啶则与诺氟沙星-Zn2+形成了共轭作用占优的三元配合物.扫描电镜及粒径分布实验表征了聚合物的物理特性,结果显示印迹聚合物的表面存在孔及孔道结构而非印迹聚合物的表面较致密不存在孔且制备的印迹聚合物的粒径均在100μm以下,其平均粒径为39μm.等温结合及选择性实验的结果表明4-乙烯基吡啶为功能单体制备的印迹聚合物的选择性识别性能优于甲基丙烯酸为功能单体制备的印迹聚合物,其特异性吸附容量和印迹指数分别为66.84μmol/g和4.207.同时在混合溶液的选择性实验中以4-乙烯基吡啶(4-VP)为功能单体制备的印迹聚合物的选择识别诺氟沙星的能力优于以甲基丙烯酸为功能单体的聚合物,其识别因子分别为3.408和2.909,而非印迹聚合物对底物的吸附量较小且识别因子均接近于1,说明非印迹聚合物对底物的识别为非选择性的.     

1-氨基乙内酰脲分子印迹聚合物的制备和吸附性能研究

以1-氨基乙内酰脲(AHD)为模板分子,α-甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,采用本体聚合方法合成了分子印迹聚合物(M IP),考察了模板分子与功能单体不同比例下制备的M IP对模板分子的吸附性能。通过Scatchard分析,表明该印迹聚合物上存在一类等价的吸附位点,其结合位点的离解常数KD=4.33mmol/L。     

二茂钛/锡/环氧化合物引发苯乙烯活性自由基聚合的研究

采用单茂钛CpTiCl3和二茂钛金属化合物(n-BuCp)2TiCl2,引发剂4-甲氧苯基缩水甘油基醚(I1),1,4-丁二醇二缩水甘油基醚(I2),4,4′-亚甲基二(N,N-二缩水甘油基苯胺)(I4)和苯基缩水甘油基醚甲醛共聚物(I5)及还原剂Sn组成引发体系,引发苯乙烯活性自由基聚合,合成线型和多臂聚合物.探讨了不同茂钛金属化合物、引发剂和还原剂对苯乙烯聚合的影响;并采用13C-NMR和GPC对聚苯乙烯的结构和性能进行了表征.结果表明所得聚合物是无规聚苯乙烯,聚合物分子量高,分子量分布窄.聚合行为属于活性自由基聚合.