Theoretical Investigation on the Luminescent Properties of Polyfluorene and Poly（fluorene-co-thiophene）

The density functional theory was employed to study the structures, ionization potentials(IPs), electron affinities(EAs), and HOMO-LUMO gaps(ΔH-L) of the oligomers. The time-dependent density functional theory(TD-DFT) and ZINDO were employed to study the lowest excitation energies(Egs) and the absorption and emission spectra of the oligomers of polyfluorene(PF) and poly(fluorene-co-thiophene)(PFT). By extrapolating ΔH-L and Egs to those of infinite chain length, band gaps and effective conjugation lengths o...     

Synthesis and Properties of Novel Poly（amine ether）s

Using aromatic bis（4-bromophenyl） ether and various aromatic diamines as the monomers, a series of novel poly（amine ether）s （PAEs） have been synthesized via palladium-catalyzed aryl amination, which is the Hartwig-Buchwald polycondensation reaction. Their structures were characterized by means of elemental analysis, FT-IR, 1^H NMR and UV-Vis spectroscopy. The results show a good agreement with the proposed structures. Their general properties were studied by DSC and TG and it＇s obvious that they show high glass transition temperatures （Tg〉200 ℃）, good thermal stability with high decomposition temperatures （TD〉500℃） and excellent solubility. The mechanical behavior of these polymers suggested that they could be considered a new class of high-performance polymers.     

Synthesis and Thermal Crosslinking Behavior of Poly（aryl ether ketone）s Containing 1,4-Naphthalene Moieties

A new monomer, 1,4-bis(4-fluorobenzoyl) naphthalene (compound 2) was synthesized via a two-step reaction. 1,4-Naphthalenedicarboxylic acid chloride (compound 1) was prepared by using the acyl chlorization reaction of 1,4-naphthalenedicarboxylic acid with thionyl chloride. The Friedel-Crafts acylation of compound 1 with fluorobenzene afforded compound 2 in a 80% yield. The polycondensation of compound 2 with various bisphenols in tetramethylene sulfone(TMS) in the presence of excess potassium carbonate as a condensation reagent was carried out at 210℃ to quantitatively afford the corresponding poly(aryl ether ketone)s (compounds 3-8) containing 1,4-naphthalene moieties. Thermal analyses showed that the polymers have Tg values ranging from 496 to 500 K and are thermally stable in air with initial mass loss above 500℃. These novel polymers exhibited an excellent solubility in organic solvents including NMP, DMAc, and chloroform, etc. In addition, the glass transition temperatures of these polymers increased and the polymers became insoluble in chloroform after treated at 260℃, indicating the occurrence of a thermal crosslinking reaction.     

Synthesis,Crystal Structure and Nonlinear Optical Properties of Nickel（Ⅱ） Complex with Schiff—base Ligand

1 INTRODUCTION Recently, the transition metal complexes and inorganic clusters have also been investigated as promising nonlinear optical materials[1～3]. In our past work, much more efforts have been made to find potential nonlinear optical derived from thiosemicarbazone and dithio-carbazates[4]. As a continuous study on new nonlinear optical materials among the -electron delocalized systems con- taining mixed sulfur and nitrogen donors[5, 6], we report herein the crystal structure and…     

Blends of Poly（lactic acid） with Thermoplastic Acetylated Starch

Blends of poly(lactic acid)(PLA) and thermoplastic acetylated starch(ATPS) were prepared by means of the melt mixing method. The results show that PLA and ATPS were partially miscible, which was confirmed with the measurement of Tg by dynamic mechanical analysis(DMA) and differrential scanning calorimetry(DSC). The mechanical and thermal properties of the blends were improved. With increasing the ATPS content, the elongation at break and impact strength were increased. The elongation at break increased from...     

Synthesis, Structure and Luminescent Properties of a New Terbium（Ⅲ） Complex with 5-Bromoisophthalic Acid

The self-assembly of 5-bromoisophthalic acid (H2BIPA) with Tb(NO3)3·6H2O under hydrothermal conditions gives rise to a 3D coordination polymer, [Tb2(BIPA)3(CH3CH2OH)]n (1), which was characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21/c with a = 19.2591(17), b = 8.2537(7), c = 18.5663(17), β = 104.4720(10)°, V = 2857.6(4)3, C26H15Br3O13Tb2, Mr = 1092.95, Dc = 2.540 g/cm3, F(000) = 2040, μ = 9.173 mm-1 and Z = 4. The final R = 0.0324 and wR = 0.0767 for 5299 observed reflections (I > 2σ(I)). Complex 1 displays an unusual three-dimensional (4,6)-connected network with (48.66.8)2(44.62)2(42.84) topology, which is different from [Tb(HBDC)(BDC)(H2O)4]·3.3H2O (BDC = isophthalate) because the -Br substituent of isophthalate results in different electronic effect and steric hindrance to change the coordination modes of carboxylate groups in the assembly process. Moreover, luminescent properties of 1 have also been investigated in the solid state.     

Synthesis of Poly[（3-octanoylpyrrole-2,5-diyl）-p-nitrobenzylidene] and Its Third-order Nonlinear Optical Property

Introduction Nonlinearoptical(NLO)organicpolymers havereceivedincreasingattentionbecauseoftheir excellentbehaviorandgoodprospectsforapplica- tiontohightechnologiessuchasopticalcommuni- cation,highdensityopticalstorageandall-optical informationprocess[1_4].Thepoly[heteroarylene- methines]andtheirderivativesareregardedaspo- tentiallyapplicativeNLOmaterials[5_8],buttheir solubilityandfilm-formingperformancearenot goodwhichisabottleneckproblemfortheapplica- tionofthesepolymers.Inthisstudy,anovel…     

Design and Synthesis of Transparent Poly （acrylonitrile-butadiene-styrene） and Relationship Between Its Phase Construction and Transparency

IntroductionABS resins have been widely applied to the field ofengineering materials because of their excellent me-chanical,electrical,physical,and chemical proper-ties.Typically,ABS resins comprise a rigid copolymermatrix-phase dispersed in a graft copol…     

Synthesis and Crystal Structure of Zn（Ⅱ） Complex with 2-Aminopyridine and Acetylacetone

1 INTRODUCTION As one kind of compound with extensive phy- siological and pharmacology activities[1], 2-amino- pyridine is easy to form complexes, and some of which may catalyse hydrolysis of ester[2]. Acetyl- acetone is an useful intermediate in the synthesis of sulfanilamide, additive and catalyst[3]. Complexes containing acetylacetone take on excellent lumines- cent properties[4]. To be an active center of some sig- nificant enzymes[5, 6], zinc takes the form of its su- pramolecular co…     

Allyl-containing Poly(aryl ether sulfone): Synthesis and Crosslinking

A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was prepared by a demethylation reaction of a methoxyphenylated PAES(PES-OCH3) in the presence of pyridine/hydrochlo- ride. The PES-OCH3 was synthesized by an aromatic nucleophilic substitution of bis(4-chlorophenyl)sulfone and (p-methoxy)phenylhydroquinone. Both DSC and solubility investigation were used to ...     

可生物降解聚酯的合成和交联产物性质研究(英)

由丙三醇、丙交酯和反丁烯二酸制得一含碳碳双健的低分子量聚酯。该聚酯由于存在不饱和键,可热引发或引发剂引发交联,可望成为环境友好材料或生物降解复合材料领域的一个有用的热固性树脂。     

单分散PPE齐聚物的合成及其荧光性质

合成了PPE的齐聚物{1,4-二[3,5-二（3-甲基-3-羟基-1-丁炔基）苯炔基]苯）（4）,通过^1H—NMR对其结构进行表征,并对其荧光性质做了研究。研究结果表明引入四个2-甲基-2-羟基-丁炔基作为取代基团后,溶解性提高。取代基的引入导致齐聚物4旋转阻力增大,溶液荧光有明显的精细结构。而4具有较好的荧光单色性,因而是一种潜在的新型荧光发射材料。     

新型含硅聚芳醚酮的合成与表征

聚醚醚酮（PEEK）因其具有优异的机械性能、耐热性和耐化学腐蚀性等而被广泛应用于航空航天、电子器件和机械仪表等领域，由于聚醚醚酮的结构特点决定其具有极好的耐溶剂性，只在浓硫酸等极少数溶剂中可以溶解，但随着应用目的和应用环境的不同，需要有可以溶解在一定溶剂中的聚醚醚酮材料。     

Synthesis and characterization of new aromatic poly(ether imide)s and their gas transport properties

A series of processable fluorinated poly(ether imide)s (PIs) were synthesized by reacting a diamine monomer, 1,4-bis-[{2′-trifluromethyl 4′-(4″-aminophenyl)phenoxy}] benzene (HQA) with six different aromatic dianhydrides e.g., BPADA, 6FDA, ODPA, BPDA, BTDA and PMDA. The polyimides showed reasonably high glass-transition temperature (T_g up to 280 °C) and high thermal stability (T_d,10 up to 558 °C). The membranes of these polymers showed tensile strength up to 107 MPa with elongation at break up to 15%, low water absorption (0.61–1.29%), low dielectric constant (2.10–3.13 at 1 MHz) and high optical transparency (λ_cut-off up to 466 nm). The PI membrane prepared from 6FDA exhibited high permeability and permselectivity for O₂/N₂ (P_O2 = 11.8 and P_O2/P_N2 = 9.44) gas pair which eventually surpassed the present upper boundary limit drawn by L.M. Robeson.     

液晶高分子聚苯撑苯并二噁唑的合成、结构与性能

本文以间苯二酚为原料,合成了缩聚单体4,6-二胺基1,3-间苯二酚盐酸盐。在多聚磷酸介质中与对苯二甲酸经分段升温缩聚得聚苯撑苯并二噁唑(PBZO).用元素分析法,X-光衍射法、X-光平板照相、FTIR和C~(13)-NMR研究了PBZO的结构.测定了PBZO/MSA体系的特性粘数。测定了PBZO的力学性能和热稳定性。结果表明PBZO是继PBZT后又一种新型的高性能液晶高分子材料。     

Synthesis and Characterization of Organosoluble Poly(imide-ether)s with Bulky 2,3-Diaryl Imidazole Moiety: Study Physical,Thermal and Optical Properties

Two new symmetrical diamines were designed and synthesized having different functional groups such as a pair of phenyl ether linkages, 2,3-diaryl substituted imidazole rings and CF₃ groups as pendant, and characterized by FT-IR, ¹H and ¹³C-NMR spectroscopy and elemental analysis. A series of new fluorescent poly(imide-ether)s (PIEs) was prepared by polymerization of the diamines with commercial tetracarboxylic dianhydrides such as pyromellitic dianhydride and 3,3′,4,4′-benzophenone tetracarboxylic dianhydride. The resulting PIEs were amorphous and had intrinsic viscosity [η] in the range of 0.42–0.51 dL/g. The weight average molecular weights (Mw) of these polymers were measured by GPC and were in the range of 28658–35595 g/mol with molecular weight distribution (MWD) of 2.12–2.27. These polymers were readily soluble in a variety of organic solvents and formed low-colored and flexible thin films with cut-off wavelength (λ₀) in the range of 385–420 nm, and all PIEs films exhibited high optical transparency. They also possessed good thermal stability with 10% weight loss temperatures (T_10%) in the range 486–537°C in N₂. The glass transition temperatures (T_g) of PIEs are in the range 251–324°C. These polymers showed fluorescence emission in film and in solution at 459–476 nm with the quantum yields in the range 4–12%.     

可控交联聚醚醚酮的合成与热性能研究

聚醚醚酮因其优异的综合性能 (耐热性、耐水解、耐辐射等 )在许多领域得到应用 [1～ 4 ] .但聚醚醚酮的玻璃化转变温度 ( Tg)较低 ( 4 2 6K) ,导致其使用温度较低 (在 5 1 3K以下 ) .为进一步提高聚芳醚酮类材料的使用温度 ,人们在聚醚醚酮主链中引入刚性结构 ,通过提高聚芳醚酮的刚性度来提高聚芳醚酮的熔点 ( Tm)及 Tg,从而提高材料的使用温度 [5,6 ] .文献 [7]中聚芳醚酮的 Tm 已经高达 741 K,但此材料很难加工成型 .通常热塑性材料具有优异的加工性能 ,但使用温度较低 .热固性材料的使用温度较高 ,但在加工固定尺寸形状铸件时存在困…     

侧链对聚对苯撑乙炔溶解性和光谱性能的影响

利用钯催化反应合成了一类侧链含不同烷氧取代基(甲氧基，辛烷氧基，十二烷氧基)的聚时苯撑乙炔，讨论了侧链烷氧取代基对聚对苯撑乙炔的分子量和溶解性的影响，比较了聚合物的紫外吸收光谱和荧光光谱特征。