Frontispiece: Controlled Self-assembly of Gold(I) Complexes by Multiple Kinetic Aggregation States with Nonlinear Optical and Waveguide Properties

Introduction of multiple kinetic aggregation states (Aggs) into the self-assembly pathway could bring complexity and flexibility to the self-assemblies, which is difficult to realize due to the delicate equilibria established among different Aggs bonded by weak noncovalent interactions. Here, we describe a series of chiral and achiral d¹⁰ Au^I bis(N-heterocyclic carbene, NHC) complexes, and the achiral complex could undergo self-assembly with multiple kinetic Aggs. Generation of multiple kinetic Aggs was realized by applying chiral or achiral seeds exhibiting large differences in elongation temperatures for their respective cooperative self-assembly processes. We further showed that the chiral Au^I self-assemblies having non-centrosymmetric packing forms exhibit nonlinear optical response of second harmonic generation (SHG), while the SHG signal is absent in the achiral analogue. The crystalline achiral Au^I self-assemblies could function as optical waveguides with strong emission polarization.     

交联聚合物合成,结构及性能的表征

结合具体实例论述了交联聚合物合成、结构及性能的仪器测试方法（如色谱、光谱、力学性质及热性能的测试）及其特点。     

Acid-Cleavable Aromatic Polymers for the Fabrication of Closed-Loop Recyclable Plastics with High Mechanical Strength and Excellent Chemical Resistance

Although closed-loop recycling of dynamic covalent bond-based plastics does not require catalysts, their mechanical strength and chemical stability remain a major concern. In this study, closed-loop recyclable poly(aryl imine) (PAI) plastics with high mechanical strength and excellent chemical resistance are fabricated by copolymerizing aromatic amines and aromatic aldehydes through dynamic imine bonds. The resulting PAI plastic with a tensile strength of 58.2 MPa exhibits excellent chemical resistance and mechanical stability in acidic and basic aqueous solutions and various organic solvents. The PAI plastics can be depolymerized in a mixed solvent of tetrahydrofuran (THF)/HCl aqueous solution through the dissociation of imine bonds, and the monomers can be facilely recovered with high purity and isolated yields due to the solubility difference between the aromatic amines and aromatic aldehydes in selective solvents. The efficient closed-loop recycling of the PAI plastic can also be realized through monomer conversion because the hydrolysis of the aromatic aldehydes generates aromatic amines. The recovered monomers can be used to re-fabricate original PAI plastics. This PAI plastic can be selectively recovered from complicated mixed polymer waste streams due to the mild depolymerization conditions of the PAI plastic and its high stability in most organic solvents.     

系列Co-aip聚物的合成、结构及表面光电性能

采用水热法合成了3种以5-氨基间苯二甲酸根为桥连配体的Co(Ⅱ)配聚物:[Co2(aip)2(bipy)]n·2nH2O(1),[Co(aip)(imH)]n(2)和[Co(aip)(phen)]n(3)(H2aip=5-氨基间苯二甲酸,bipy=2,2′-联吡啶,imH=咪唑,phen=1,10-邻菲啰啉).通过X射...     

三偏磷酸钠交联壳聚糖膜的制备及其性能研究

将充分溶胀的壳聚糖膜置于一定浓度的三偏磷酸钠溶液中进行交联反应制备出交联壳聚糖膜。用傅立叶变换红外光谱(FT-IR)、X-射线衍射(XRD)和扫描电镜(SEM)表征了其结构,并测试了其吸水率、力学性能和酶降解性能。研究结果表明,交联作用明显提高了膜的抗张强度和抗水性,并有效地降低了溶菌酶对其降解速率。该交联膜有望用作可控降解生物医用材料。     

试论高聚物结构与性能关系的三个层次

高分子物理的基本任务之一就是探求高聚物的结构与性能,揭示结构与性能之间的内在联系及其基本规律。高聚物结构与性能的关系应该包含3个层次:通过分子运动联系的"分子结构与材料性能"关系、通过产品设计联系的"凝聚态结构与制品性能"关系和通过凝聚态物理知识联系的"电子态结构与材料功能"关系。传统教材上仅讲授"结构与性能关系",有相当的局限性,需要在研究生阶段补充有关"凝聚态结构与制品性能"关系和"电子态结构与材料功能"关系的课程。     

制备方法对氧化镁负载的钼钒磷酸铜催化剂结构和催化性能的影响

在乙醇溶液中采用不同的浸渍方法制备了氧化镁负载的钼钒磷酸铜催化剂，利用XRD、IR和BET比表面测定等测试手段对催化剂进行了表征．XRD和IR表征结果表明，负载的钼钒磷酸铜在载体表面均匀分散，而且能够保持Keggin型结构．XRD和BET比表面测定结果说明，经12h浸渍制备的催化剂（H4PMo11VO40-CuO／MgO12H）化学和结构性能发生变化；其它两种方法制备的催化剂（H4PMo11VO40-CuO／MgO和Cu2PMo11VO40／MgO）没有化学和结构性能的变化，而且这两种催化剂具有相近的表征结果，说明两种催化剂具有相似的结构特征，以正己醇氧化脱氢生成正己醛反应评价了催化剂的催化反应性能，结果表明，H4PMo11VO40-CuO／MgO和Cu2PMO11VO40／MgO催化剂显示出比H4PM011VO40-CuO／MgO12H更高的催化反应活性。     

自成核对等规聚丙烯结晶行为和性能的影响

结晶聚合物的结晶动力学影响其形态结构 ,而形态结构的变化对材料的性能有着重要的影响 [1] .成核剂能有效地降低聚合物的球晶尺寸 ,提高材料的性能 [2 ] ,因此被广泛地应用于工业生产中 .自成核 (self- seeding nucleation)是指聚合物自身的微小晶粒作为晶核而诱导结晶生长的一种成核方式 [3 ,4 ] ,它具有很高的成核效率 ,并能有效地降低球晶尺寸 .本文研究了等规聚丙烯的自成核过程、结晶行为、形态结构及其对材料性能的影响 .1　实验部分1 .1　样品的制备　等规聚丙烯 (i PP)为广东茂名石油化学工业公司产品 ,牌号为 T3 6 F.将 i PP粒…     

Investigation of the Structure and Properties of Crosslinked Polymers Based on Oligocarbonate Methacrylates in Film Formation

The effect of structure and flexibility of an oligomeric block of oligocarbonate methacrylates (OCM) as well as of various modifiers on the coating formation, the structure, and properties of crosslinked polymers formed under conditions of adhesive interaction has been studied. Reactivity and conversion of OCM during polymerization increase in coatings formed from oligomers with short and rigid blocks, capable of forming on the substrate a network from the ordered anisodiametric structural elements with high adhesive properties, as distinct from the globular structures appearing in the formation of the network from the oligomers with more flexible blocks. The tendencies observed have been explained with the aid of a mechanism of network formation relating the morphology of the resultant crosslinked polymers to the flexibility (conformation) of the chains of the branched polymer obtained in the initial stage of polymerization and representing a matrix of the corresponding crosslinked structures. The mode of action of modifiers is markedly dependent on the nature and flexibility of the oligomeric block.     

Entanglement of Thread Molecules and Its Influence on the Properties of Polymers

This article shows the extent to which the entanglement of threadlike molecules can influence many of the properties of deformable polymers and of solutions of macromolecular substances. Thus, the molecular concept of entanglement leads to quantitative predictions of the dependence of the entanglement number on the nature of the polymer, its concentration, and extension. Experimental values of the relaxation modulus confirm these predictions for melts and solutions. The influence of entanglemnt on relaxation and flow processes leads to very simple relationships for the magnitudes of the structural viscosity and the shear stress at which the structural viscosity starts to become measurable. Osmotic pressures, light scattering intensities, and diffusion coefficients of concentrated solutions can be derived quantitatively from the conformational constraints due to entanglement. Entanglement is effective above a concentration at which the three-dimensional coils fill the solution volume, and probably also at lower concentrations. At very high concentrations entangled structures may be formed which drastically reduce the number of possible conformations. The swelling and extension behavior of cross-linked deformable polymers can be understood only if entanglement is taken into account.     

Studies on the Structure, Properties of Ferroaluminophosphate Molecular Sieve (FAPO-5) and Chemical State of Iron in the FAPO-5 Molecular Sieve

The pure Ferroaluminophosphate molecular sieve(FAPO-5) was synthesized by hydrothermal crystallization. The crystal structure of FAPO-5 was studied via XRD, electron probe energy dispersion analysis, Mossbauer spectroscopy, EPR, XPS and IR, the parameters of unit cell and chemical composition of FAPO-5 were determined. The result has that the structure of FAPO-5 is AlPO -5 type and Fe2+ Fe3+ are incorporated into the framework of FAPO-5 molecular sieve. In addition, the chemical state of iron in FAPO-5 molecular sieve were studied and the adsorption properties, surface acidity and thermal stability were also investigated.     

The Effect of Branching Structure on the Properties of Entangled or Non-covalently Crosslinked Polyisoprene

The branching structures in natural rubber(NR) were believed to be critical for its superior mechanical properties. However, it is challenging to unravel the branching structure-function relationship of NR due to the complexity of the system. Herein, polyisoprene-(polyisoprene-g-polylactide)(PI-PLA) as model compound containing branching structure was designed and synthesized, which can improve the modulus, strength and viscoelasticity activation energy compared to those of the pristine polyisoprene(PI). The reason is that the branching structure contributes to the entanglement between polyisoprene chains. In order to probe the effect of branching structure on noncovalently crosslinked system, the polyisoprene block of PI-PLA was epoxidized and mixed with Fe~(3+) ions to introduce coordination bonds. Compared with the linear counterpart, the branching structure obviously enhanced activation energy of coordinated polyisoprenes, remarkably improving the mechanical properies of elastomer.     

Synthesis,Crystal Structure and Nonlinear Optical Properties of a new cluster compound: MoS4Cu3(PyPPh2)3Cl

Reaction of [NH₄]₂[MoS₄], CuCl and PyPPh₂ in the solid state produces a cube-like cluster. The cluster crystallizes in the orthorhombic space group P2₁2₁2₁ with four formula units in a cell of dimensions a = 12.8980(10) , b = 17.6820(10), c = 22.665(2) Å. Anisotropic refinement for all nonhydrogen atoms yielded the values R = 0.0397 and R _w = 0.1185 for 8803 observed reflections. The structure is built up from three [Cu(Ph₂PPy)]⁺ units bridged by MoS^2? ₄ to form a tetranuclear symmetrical cube-like molecule. Investigation of the third-order optical nonlinear value showed that it exhibits a considerable nonlinear absorptive and self-defocusing effect with α₂ = 1.3 × 10^?11 m w^?1 and n ₂ = ? 3.2 × 10^?18 m² w^?1 in a 1.5 × 10^?4 M DMF solution.     

偶氮复合发泡剂对交联聚氯乙烯泡沫结构和性能的影响

采用异氰酸酯和环氧树脂作为交联剂,偶氮二异丁腈（AIBN）和偶氮二甲酰胺（AC）作为发泡剂制备了交联聚氯乙烯泡沫材料。 通过扫描电子显微镜分析了两种发泡剂的粒径、比例以及用量对泡孔结构的影响。 结果表明,AIBN的粒径对泡沫的泡孔结构影响不大,但其用量增加导致泡沫密度减小;AC的粒径对泡孔结构产生一定的影响,最优的粒径范围为8～20 μm,并且随着用量增加,泡孔尺寸变小,但对密度影响不大。 采用DSC研究了AIBN和AC在预混料中的分解情况,提出了两种发泡剂影响泡沫的泡孔结构的机理。 对泡沫材料力学性能的分析表明,泡沫的强度随密度的增加而增加,剪切变形则在60～80 kg/m3密度范围内出现最大值。     

Molecular Structure and Magnetic Properties of the Binuclear Phthalato-Bridged Species Bis[(N-(2-(Diethylamino)Ethyl)Salicylidenaminato)-Copper(II)] Trihydrate

The crystal structure of ( w -phthalato)bis[(N-(2-(diethylamino)ethyl)-salicylidenaminato)copper(II)-trihydrate,[Cu₂(salNet₂)₂(w m phthal)] · 3H₂O, where salNet₂= N-(2-(diethylamino)ethyl)salicylidenaminate, has been determined by single-crystal X-ray analysis. It crystallizes in the monoclinic system, space group P2₁/c, with a = 19.9109(9), b = 10.0465(4), c = 18.5837(8)Å, and g = 100.625(1)°. In the molecular structure the two copper(II) ions are bridged by the phthalato ligand coordinated in an amphimonodentate mode and the local geometry around both copper(II) ions is square planar. Magnetic susceptibility data for the complex as a function of temperature show weak exchange interactions. The fitting of these data to the HDVV (? = -2J ? ₁ ?₂), S₁ = S₂ = 1/2 spin exchange model, yields a 2J value of -0.34 cm^-1. An orbital interpretation of the observed weak antiferromagnetic interactions is presented based on the results of extended Hückel calculations on a model molecule.     

Synthesis,Structure and Properties of a Zinc(II) Complex with the Lapacholate Anion and Ethanol as Ligands

The reaction of lapachol, 2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphtoquinone, C₁₅H₁₄O₃, with zinc acetate, in ethanol, produces a chelate formula Zn(C₁₅H₁₃O₃)₂(C₂H₆O)₂, whose structure has been determined by single crystal X-ray diffraction. It pertains to the triclinic system, space group P I (No. 2), a = 8.2380(3) Å, b = 9.4900(2) Å, c = 11.0110(4) Å, α = 112.536(2)°, β = 91.204(2)°, γ = 92.664(2)°, Z = 1. Some spectroscopic and chemical properties of the complex are also reported.     

Transition Metal Halide Salts of 2-Amino-5-Substituted-Pyridines: Synthesis,Crystal Structure and Magnetic Properties of Two Polymorphs of (5-IAP)2CuCl4[5-IAP = 2-Amino-5-Iodopyridinium]

The reaction of anhydrous CuCl₂ with HCl and 2-amino-5-iodopyridine in 1-propanol resulted in two polymorphs of (5-IAP)₂[CuCl₄] [5-IAP = 2-amino-5-iodopyridinium], one as red rods (1) and one as orange prisms (2). The two polymorphs have been characterized by single crystal x-ray diffraction and variable temperature magnetic susceptibility. Crystal data: triclinic, P-1, F(000) = 606, MoK _α (λ = 0.71073 Å): for (1): a = 9.248(6), b = 10.202(7), c = 10.368(7) Å, α = 102.451(9), β = 96.662(8), γ = 96.725(8)°, V = 938.4(11) &Aringsup3;, Z = 2, D_calc = 2.291 Mg/m³, μ = 5.020 mm^?1, R = 0.0392 for [|I|≥2σ(I)]. For (2): a = 8.966(2), b = 10.755(2), c = 11.359(2) Å, α = 89.63(3), β = 68.04(3), γ = 69.07(3)°, V = 938.6(3) &Aringsup3;, Z = 2, D _calc = 2.291 Mg/m³ , μ = 5.019 mm^?1 , R = 0.0217 for [|I|≥2σ(I)]. The crystal packing for both polymorphs suggests that their magnetic behavior should be that of weakly interacting alternating linear chains. Temperature dependent susceptibility measurements yield: for 1 , C = 0.43, g = 2.14, θ = m 1.98; for 2, C = 0.45, g = 2.19, θ = ?4.15.     

天然胶乳中蛋白质和磷脂对橡胶分子结构的影响

采用碱性蛋白酶和磷脂酶处理天然胶乳,制备脱蛋白胶乳和脱脂胶乳,结合原子吸收光谱仪、核磁共振交联密度仪、凝胶色谱(GPC)等仪器对处理前后的天然胶乳进行了分析。通过对比分析,发现酶处理后胶乳分子量降低,分子量分布变宽,金属离子浓度、凝胶含量和交联密度均降低。结果表明,金属离子与天然橡胶中的蛋白质、磷脂间存在着物理的或化学的作用力;蛋白质、磷脂在天然橡胶中起到节点的作用,有利于形成分子间交联,增大天然橡胶分子量,形成分子间网络结构。     

Crystal Structure and Magnetic Properties of a Vanadium (IV) Pyrophosphate: Rb2V3P4O17

The crystal structure of Rb₂V₃P₄O₁₇ has been determined from single-crystal X-ray diffraction data. Rb₂V₃P₄O₁₇ crystallizes in the orthorhombic space group Pnma (No. 62) with a = 17.502(7), b = 7.292(2), c = 11.399(6) ų, V = 1455(1) ų, Z=4, R=0.0295, R_W = 0.0320 for 1129 unique reflections with I > 2.5 σ(I). The structure contains intersecting tunnels where the Rb⁺ cations are located. The framework can be described as consisting of V²O₁₀ units formed from one VO₅ square pyramid and one VO₆ octahedron sharing a corner, and infinite chains of corner-shared VO₆ octahedra, which are linked in three dimensions by pyrophosphate groups. The structural formula is Rb₂(VO)₃(P₂O₇)₂. A single-phase product can be obtained by heating appropriate amounts of Rb₄V₂O₇, VO₂, V, and P₂O₅ in an evacuated fused silica tube at 950°C. Powder magnetic susceptibility data confirm the presence of V⁴⁺ (d¹) ions without magnetic ordering down to 3 K.