反应性梯形聚氢基倍半硅氧烷合成方法的改进

对反应性梯形聚氢基倍半硅氧烷 (H T)的合成方法进行了改进 .首先利用硅羟基与硅氯基之间的脱氯化氢缩聚来代替以前采用的硅羟基间脱水缩聚反应 ,进一步提高了作为梯撑的对苯二胺之间氢键在聚合反应中的模板作用 .另外利用三甲基氯硅烷与对苯二胺梯撑的聚硅氧烷中间体的末端硅羟基进行封端反应 ,从而保证在脱除对苯二胺梯撑模板分子过程中避免进一步的无规缩合导致支化或交联 ,得到的反应性梯形聚氢基倍半硅氧烷 (H T)的规整性有所改善 .热分析结果表明与单链聚二甲基硅氧烷的Tg(- 12 3℃ )相比 ,其Tg 高达 117 0℃ ,证明这种梯形高分子具有刚性链结构 .尤其是2 9Si NMR谱中代表梯形主链上硅原子 (SiO3 2 )峰的基线宽度Δ =5 ,而采用硅羟基间脱水缩合方法得到聚合物的Δ =8～ 10 .表明该反应性梯形聚氢基倍半硅氧烷H T的规整性得到了明显的提高 .而且 ,该聚合物又是第一个可溶性、反应性、纯梯形主链无机高分子 ,它可以进一步通过硅 氢侧基接枝反应制备不同类型的梯形无机主链功能高分子 .     

超分子构筑调控合成结构规整的梯形聚合物及其应用研究

综述了"超分子构筑调控的逐步偶联/聚合法",该方法将高分子化学与超分子化学相结合,利用多种类型的超分子弱键协同作用首先构筑预期的梯形超分子结构,再经聚合得到共价键梯形高分子.利用该方法合成了一系列结构规整的氧桥基和有机桥基梯形聚硅氧烷以及碳基梯形聚酯,并利用侧基间π-π叠加作用实现了对聚合物立体构型控制.扼要介绍了梯形聚合物在先进材料方面的应用,例如梯形聚硅氧烷液晶光致取向膜;由梯形聚硅氧烷合成的管状聚硅氧烷在高室温储存期微电子环氧塑封料方面的应用;以及基于梯形聚硅氧烷的拟筛板聚合物在二阶非线性光学材料方面的应用等.     

“逐步偶联聚合反应”在研制有序交联高分子及复合物中的应用

用“逐步偶联聚合反应”这一新的合成方法可制备不同等级的微观结构可控的有序交联网状高分子,包括可溶性的一维梯形或管状高分子、不溶性的二维或三维筛板状高分子,新型的反应性梯形聚硅氧烷包括氢梯、乙烯基或丙烯基梯、乙氧基梯及其共聚物是功能性梯形高分子的前体,由此衍生出“鱼骨形”和“划艇形”液晶和非线性高分子、盘状金属络合物液晶高分子以及管状聚硅氧烷。对功能化梯形降硅氧烷进行了有趣的应用探索,包括用于稳定液     

1-苯基-3-(4-硝基苯基)-5-(9-蒽基)-2-吡唑啉分子内高位共轭

通过对1 苯基 3 (4 硝基苯基) 5 (9 蒽基) 2 吡唑啉及其相关化合物的吸收光谱进行比较研究,发现该分子的吸收不同于分子内"Ar—N—N=C—Ar"发色团与蒽发色团的叠加.其中"Ar—N—N=C—Ar"发色团的吸收系数增强了12倍,存在极大的增色效应,蒽的精细吸收峰也均红移了20nm左右.说明两者存在基态下的相互作用.优势构象理论分析表明这是由于基态π电子轨道重叠的高位共轭效应引起的.该发现将有助于解释该类分子激发态下发色团间的非共轭电荷转移以及能量转移,并为寻找更大吸收系数的该类化合物提供了较好的方法.     

三维水网配合物[Ni(phen)_2(CO_3)]·7H_2O的水热合成、晶体结构及其电化学性质

用水热法合成了离子型配合物[Ni(phen)2(CO3)].7H2O(1,phen=1,10-邻菲啰啉),其结构经IR和元素分析表征。X-射线单晶衍射分析表明,1属单斜晶系,P21/c空间群,晶胞参数a=0.989 97(8)nm,b=2.637 60(2)nm,c=1.058 43(9)nm,β=105.917(2)°,V=2.657 8(4)nm3,Z=4,Dc=1.513 g.cm-3,F(000)=1 004,μ=0.795 mm-1,R1=0.050 1,wR2=0.110 4。相邻的1中结晶水和配位的碳酸根通过O-H┈O和C-O┈H构成三维超分子氢键网络。在水溶液中测试了1的电化学性质,循环伏安法表明1具有较好的电化学性质,存在一对氧化还原峰,其峰电位分别为0.31 V和-0.40 V。     

N,N′-亚水杨基皮考林酰肼合铜的晶体结构及荧光性质

在DMF和CH3 OH中 ,以N ,N′ 亚水杨基皮考林酰肼 (简写为H2 sphz)和高氯酸铜合成了双核配合物[Cu2 (sphz) (DMF) 3 H2 O]·(ClO4) 2 。X射线衍射实验结果表明 ,标题配合物晶体属于单斜晶系 ,空间群为P2 1/c,分子式C2 2 H3 2 Cl2 Cu2 N6O14 ,晶体学参数a =1 0 81 2 0 ( 3 )nm ,b=2 .5 71 87( 7)nm ,c=1 1 777( 3 )nm ,β=1 0 4 1 472( 5 )°,V =3 1 75 7( 2 )nm3 ,Z =4,Dc=1 679Mg/m3 ,F( 0 0 0 ) =1 640 ,μ(MoKα) =1 5 82mm-1,R =0 0 3 5 8,Rw=0 1 0 0 7。2个铜 (Ⅱ )原子 ,一个呈畸变的NO3 平面体正方形配位构型 ,一个具有畸变的N2 O3 四角锥配位构型 ,晶体内每 2个分子通过分子间氢键作用形成缔合分子对。红外光谱表明 ,配体在形成配合物后 ,ν(CO)和ν(CN )红移。电子光谱表明 ,存在d d 和π π 跃迁。荧光光谱表明 ,配合物金属对配体n π 激发 ( 3 1 0nm)引起的发射峰有较大的影响。     

加雷沙星的吸附伏安法测定

在0.3mol·L-1KH2PO4-Na2HPO4(pH6.40)底液中,加雷沙星(Garenoxacin,简称GRX)在汞电极上有一线性扫描还原峰,峰电位EP=-1.12V(vsAg/AgCl),该峰具有明显的吸附性;吸附粒子为GRX中性分子,测得GRX在汞电极上的饱和吸附量Гs=3.92×10-11 mol·cm-2,每个GRX分子所占电极面积为1.94nm2,GRX在汞电极上的吸附符合Langmuir吸附等温式;测得吸附系数β=1.14×106,25℃时的吸附自由能ΔGθ=-29.62kJ·mol-1,电极反应电子数n=2,不可逆体系动力学参量αna=1.04,表面电极反应速率常量ks=0.25s-1;建立了吸附溶出伏安法测定GRX的最佳条件,方法的检出限为2.0×10-8 mol·L-1.     

含能配合物[Mn(DAT)6](ClO4)2的合成、晶体结构、热行为及感度性质

合成了新型含能配合物[Mn(DAT)6](ClO4)2(DAT=1,5-二氨基四唑), 用X射线单晶衍射法测定了其晶体结构. 该晶体属三方晶系, P3c1空间群, a=b=1.18435(17) nm, c=1.3081(3) nm, α=β=90°, γ=120°, V=1.5891(5) nm3, Z=2. 该配合物分子结构单元中有1个Mn2+离子、6个DAT分子和2个ClO4-离子. 由6个DAT分子中的6个N原子与中心Mn2+离子配位形成六配位、非中心对称的畸变八面体结构. 利用元素分析、差示扫描量热分析(DSC)、热重-微分热重分析(TG-DTG)等方法进行了表征, 研究了其感度性能. 研究结果表明, 该配合物对外界刺激具有很高的响应性和危险性.     

钒磷酸盐(NH3CH2CH2NH2)[VOPO4]的水热合成和结构表征

标题化合物是在反应物摩尔比为V2O5H3PO4H2NCH2CH2NH2H2O=0.5543.6265时,175℃水热反应5 d合成的.其结构特点是钒八面体[VO5N]共用角顶的氧形成"之"字型链,链间由[PO4]共角项连接成层;乙二胺分子的一个N直接与V配位,并伸向层间.相邻层间存在强氢键.晶体学数据单斜晶系,P21/c(No.14),a=0.92108(2)nm,b=0.72851(1)nm,c=0.98204(2)nm,β=101.269(7)°,V=0.6462(4)nm3,Z=4,Dc=2.303g·cm-3,R1=0.0417,wR2=0.0999.     

N,N′-亚水杨基皮考林酰肼合铁(Ⅱ)的晶体结构和荧光性质

合成了N,N′-亚水杨基皮考林酰肼(HL)及其铁配合物[FeL2](C26H20FeN6O4,Mr=536 33).X射线衍射实验结果表明,标题配合物晶体属于正交晶系,空间群为Pbcn,晶体学参数:a=1 4970(1)nm,b=1 51556(9)nm,c=2.0920(2)nm,V=4 7462(6)nm3,Z=8,Dc=1 501Mg·m-3,F(000)=2208,μ(MoKα)=0 682mm-1,R=0 0695,Rw=0 1502.在配合物[FeL2]中,铁(Ⅱ)原子具有扭曲的八面体配位构型,晶体通过分子间氢键作用形成缔合分子对.红外光谱表明,配体在形成配合物后,ν(CO)和ν(CN)红移.电子光谱表明存在π-π 和d-π 的跃迁;荧光光谱表明,配合物金属对配体n-π 激发引起的荧光发射峰有较大的影响.     

Three-Strand Conducting Ladder Polymers: Two-Step Electropolymerization of Metallorotaxanes

Sequential polymerization of supramolecular metallorotaxane complexes results in three-stranded conducting ladder polymers. The internal polymer is "sandwiched" between the other two polymers to give molecular wires that are effectively insulated when the outer polymers are in their nonconducting state (shown schematically). The intermolecular conductivity can be mediated by the Cu(1+)/Cu(2+) redox couple.     

Supramolecular template‐directed synthesis of stable and high‐efficiency photoluminescence 9,10‐diphenylanthryl‐bridged ladder polysiloxane

A soluble well‐defined 9,10‐diphenylanthryl‐bridged ladder polysiloxane ( DPAnLP ) was prepared via supramolecular assembly‐directed condensation polymerization of silanols. The ladder superstructure ( LS ) was obtained via a synergistic interaction of H‐bonding and π–π stacking between polymerizable precursor 2‐tert‐butyl‐9,10‐bis(methyldihydroxylsilyl)anthracene in organic solvent. The resultant LS was then used as template to direct the condensation of silanol groups to obtain DPAnLP with high regularity. It was found that DPAnLP can emit blue light (430 nm) with great stability and high efficiency in both solution and solid film, which indicated a well organizing of fluorophore within confined environment (ladder structure). TGA and DSC measurements showed that DPAnLP had good thermal stability, and cyclic voltammetry detection gave a low‐lying highest occupied molecular orbital level. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2491–2497, 2010     

Supramolecular Polymerization from Controllable Fabrication to Living Polymerization

Supramolecular polymers have attracted plenty of interest in the scientific community; however, developing controllable methods of supramolecular polymerization remains a serious challenge. This article reviews some recent developments of methods for supramolecular polymerization from controllable fabrication to living polymerization. Three facile methods with general applicability for controllable fabrication of supramolecular polymers have been established recently: the first method is a self‐sorting approach by manipulating ring–chain equilibrium based on noncovalent control over rigidity of monomers; the second is covalent polymerization from supramonomers formed by noncovalent interactions; and the third is supramolecular interfacial polymerization. More excitingly, living supramolecular polymerization has been achieved by two elegant strategies, including seeded supramolecular polymerization under pathway complexity control and chain‐growth supramolecular polymerization by metastable monomers. It is anticipated that this review may provide some guidance for precise fabrication of supramolecular polymers, leading to the construction of supramolecular polymeric materials with controllable architectures and functions.     

Synthesis of ladder‐like polynorbornenes with n‐type perylenendiimide derivatives as bridges

Polymerizable tetrachloro‐perylenediimdes containing endo/exo‐norbornene groups on both imide sides were designed and synthesized. Endo/Exo‐type soluble ladder‐like polynorbornenes with perylenediimide (PDI) as bridges were prepared by ring‐opening metathesis polymerization (ROMP). XRD characterizations showed that the ladder‐like polynorbornenes had ordered structures similar to the supramolecular precursors assembled from the corresponding monomers. TGA measurements demonstrated great thermal stabilities for the both target P1‐Endo and P2‐Exo with T_d of about 320 °C at 5 wt % loss, respectively, which is important for further application in devices. Both polymers have good solubility in common organic solvents and easy to form thin films. Photophysical studies and cyclic voltammetry investigations reveal that polynorbornene films have wide‐range absorption from 400 nm to 600 nm and the HOMO/LUMO energy levels could be matched well with the donor‐PCzTh‐TVDCN. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Finely Controlled Circularly Polarized Luminescence of a Mechano‐Responsive Supramolecular Polymer

Finely controlled circularly polarized luminescence (CPL) supramolecular polymerization based on a tetraphenylethene core with four l ‐ or d ‐alanine branch side chains (l ‐ 1 and d ‐ 1 ) in the solution state is presented, resulting from the tuning of mechanical stimulus. Weak, green emissions of l ‐ 1 and d ‐ 1 in tetrahydrofuran (THF) were converted into strong blue emissions by tuning the mechanical stimulus. The strong blue emissions were caused by an aggregation‐induced emission (AIE) effect during the formation of a supramolecular polymer. Lag time in the supramolecular polymerization was drastically reduced by the mechanical stimulus, which was indicative of the acceleration of the supramolecular polymerization. A significant enhancement of circular dichroism (CD) and CPL signals of l ‐ 1 and d ‐ 1 was observed by tuning the rotational speed of the mechanical stimulus, implying that the chiral supramolecular polymerization was accelerated by the mechanical stimulus.     

Supramolecular Polymerization Controlled through Kinetic Trapping

A method of controllable supramolecular polymerization through kinetic trapping is developed. To this end, two bifunctional monomers with cucurbit[7]uril (CB[7]) and adamantane end groups were synthesized. The CB[7]‐containing monomer was presaturated with a pH‐responsive competitive guest for kinetic control. Then, the kinetics of supramolecular polymerization of the two monomers was easily controlled through the modulation of pH. As a result, supramolecular polymerization was kinetically trapped at certain stages, and supramolecular polymers with different molecular weights were obtained. It is anticipated that this research will enrich the methods of controllable supramolecular polymerization.     

Stereoselective Seed-Induced Living Supramolecular Polymerization

Stereoselective and temporally controlled supramolecular polymerizations are ubiquitous in nature and are desirable attributes for the design of chiral, well-defined functional materials. Kinetically controlled, living supramolecular polymerization (LSP) has emerged recently for the synthesis of supramolecular polymers with controlled length and narrow dispersity. On the other hand, stringent design requirements for chiral-discriminating monomers precludes the stereoselective control of the supramolecular polymer structure. Herein, a synergetic stereo- and structural control of supramolecular polymerization by the realization of an unprecedented stereoselective seed-induced LSP is reported. Homochiral and seeded growth is demonstrated with bischromophoric naphthalene diimide (NDI) enantiomers with a chiral binaphthyl amine core, exhibiting strong self-recognition abilities and pathway complexity.     

Supramolecular Polymerization of C3‐Symmetric Organogelators: Cooperativity,Solvent, and Gelation Relationship

A systematic study of the influence of solvent and the size of C₃‐symmetric discotics on their supramolecular polymerization mechanism is presented. The cooperativity of the self‐assembly of the reported compounds is directly related to their gelation ability. The two series of C₃‐symmetric discotics investigated herein are based on benzene‐1,3,5‐tricarboxamides (BTAs) and oligo(phenylene ethynylene)‐based tricarboxamides (OPE? TAs) that are peripherally decorated with achiral ( 1 a and 2 a ) or chiral N‐(2‐aminoethyl)‐3,4,5‐trialkoxybenzamide units ( 1 b and 2 b ). The supramolecular polymerization of compounds 1 a , b and 2 a , b has been exhaustively investigated in a number of solvents and by using various techniques: variable‐temperature circular dichroism (VT‐CD) spectroscopy, concentration‐dependent ¹H NMR spectroscopy, and isothermal titration calorimetry (ITC). The supramolecular polymerization mechanism of compounds 2 is highly cooperative in solvents such as methylcyclohexane and toluene and is isodesmic in CHCl₃. Unexpectedly, chiral compound 1 b is practically CD‐silent, in contrast with previously reported BTAs. ITC measurements in CHCl₃ demonstrated that the supramolecular polymerization of BTA 1 a is isodesmic. These results confirm the strong influence of the π‐surface of the central aromatic core of the studied discotic and the branched nature of the peripheral side chains on the supramolecular polymerization. The gelation ability of these organogelators is negated in CHCl₃, in which the supramolecular polymerization mechanism is isodesmic.     

界面超分子聚合

超分子聚合物诞生于高分子化学与超分子化学的交叉融合,一般是指单体间通过非共价键作用连接形成的聚合物,并在溶液或体相中表现出类似聚合物的性质。目前超分子聚合物一般通过均相溶液聚合制备得到,但溶液中的超分子聚合是一个自发的组装过程,具有浓度依赖性,组装过程不易可控。为解决此问题,研究人员可以将超分子聚合从均相溶液转移到界面,在界面上可控地制备超分子聚合物。通过界面聚合制备超分子聚合物具有一些独特的优势,如可以制备得到分子量更高的超分子聚合物,易于制备一些缺陷少、面积大、有序的二维超分子聚合物等。本文基于在液-液、气-液和固-液三种界面上制备超分子聚合物的一些代表性工作,介绍了界面超分子聚合方法和应用,并展望其未来发展。