New Poly(arylene ethynylene)s Consisting of Electron‐Deficient Aryleneimide Units

Summary: A new class of poly(arylene ethynylene)s (PAEs) containing an electron‐deficient N‐alkylphthalimide unit was prepared by means of a Sonogashira reaction. Complete solubility of the PAEs was observed by utilizing a 2,6‐diisopropylphenyl side chain. The chemical structure of the novel soluble polymer 3c was confirmed by NMR spectra, whereas the insoluble polymers were characterized by elemental analysis and IR spectra. Fluorescence measurements of 3c indicate a rigid structure and high symmetry in the excited state.

     

SBS-g-GMA对PPO/PBT合金性能影响的研究

采用熔融共混法制备了SBS—g-GMA/PPO/PBT、SBS/PPO/PBT的合金,通过HAAKE、MI、DSC、SEM等方法对合金进行了表征。研究了SBS—g—GMA对PPO/PBT合全相容性的影响,探讨了合全的流变性能、热性能、形态结构和力学性能。     

A NEW POLYMERIC FLAME RETARDANT ADDITIVE FOR NYLON

The present paper deals with the use of a new polymeric flame retardant material, polyphenylene sulphide (PPS) for plastics. Incorporation of 15—20% PPS into nylon-6 has provided UL V-0 rating for the system and there is enhancement in tensile and flexural properties. The results obtained on the thermal, crystallization and flow characteristics of the nylon-PPS system upto a loading of 40% PPS are also discussed.     

含三嗪或查尔酮结构聚对亚苯基亚乙炔基的合成及其荧光特性

聚对亚苯基亚乙炔基(polyphenyleneethynylene,PPE)是主链由苯环与乙炔基交替相联的线型聚合物,其共轭主链的电子流动性好,在溶液中有较高的荧光量子效率,具有独特的光电性能,已在分子导线、分子传感器、液晶显示、发光二极管和能量传输材料等领域得到应用[1~4].在聚对亚苯基亚     

Nanostructured Carbonaceous Materials from Molecular Precursors

Nanostructured carbonaceous materials, that is, carbon materials with a feature size on the nanometer scale and, in some cases, functionalized surfaces, already play an important role in a wide range of emerging fields, such as the search for novel energy sources, efficient energy storage, sustainable chemical technology, as well as organic electronic materials. Furthermore, such materials might offer solutions to the challenges associated with the on‐going depletion of nonrenewable energy resources or climate change, and they may promote further breakthroughs in the field of microelectronics. However, novel methods for their preparation will be required that afford functional carbon materials with controlled surface chemistry, mesoscopic morphology, and microstructure. A highly promising approach for the synthesis of such materials is based on the use of well‐defined molecular precursors.     

Syntheses,properties, and field‐effect transistors of small band gap quinoxaline‐ and thienopyrazine‐vinylene/ethynylene conjugated polymers

New conjugated copolymers of quinoxaline (AQ) and thienopyrazine (ATP) with vinylene (V) or ethynylene (E), poly[2,3‐bis(4‐(2‐ethylhexyloxy)phenyl)‐quinoxaline vinylene] (PAQV), poly[2,3‐bis(4‐(2‐ethylhexyloxy)phenyl)‐quinoxaline ethynylene)] (PAQE), poly[2,3‐bis(4‐(2‐ethylhexyloxy)phenyl)‐thieno[3,4‐b]pyrazine vinylene] (PATPV), and poly[2,3‐bis(4‐(2‐ethylhexyloxy)phenyl)‐thieno[3,4‐b]pyrazine ethynylene] (PATPE), were successfully synthesized by Stille coupling reaction. The optical band gaps of the PAQV, PAQE, PATPV, and PATPE were 1.86, 2.00, 0.88, and 0.90 eV, respectively, whereas the electrochemical band gaps were 1.99, 2.06, 1.00, and 1.06 eV, respectively. The reduced steric hindrance by the incorporation of the V or E linkage or the intramolecular charge transfer between the acceptor and the V or E linkage led to the small band gap. The AQ/ATP‐vinylene copolymers exhibited much higher vis/near infrared absorption intensity than the AQ/ATP‐ethynylene suggested the stronger π–π* transition intensity in the former and led to better charge‐transporting characteristics. The saturation field‐effect hole mobilities of the PATPV were 2.1 × 10^?3, 1.7 × 10^?2, and 1.1 × 10^?2 cm² V^?1 s^?1 on bare, octyltrichlorosilane (OTS)‐treated, and octadecyltrichlorosilane(ODTS)‐treated SiO₂, respectively, with on‐off current ratios of 35, 6.02 × 10², and 7.56 × 10². On the other hand, the estimated field‐effect transistor hole mobility of the PATPE was in the range of 1.7 × 10^?6–8.1 × 10^?4 cm² V^?1 s^?1, which was significantly smaller than those of the PATPV. The small band gaps and high charge carrier mobility of the prepared copolymers suggested their potential applications for near‐infrared electronic and optoelectronic devices. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 74–81, 2010     

Ethynylene‐containing donor–acceptor alternating conjugated polymers: Synthesis and photovoltaic properties

Four ethynylene‐containing donor‐acceptor alternating conjugated polymers P1 – P4 with 2,5‐bis(dodecyloxy) substituted phenylene or carbazole as the donor unit and benzothiadiazole (BTZ) as the acceptor unit were synthesized and used as donor polymers in bulk heterojunction polymer solar cells. The optical, electrochemical, and photovoltaic properties of these four polymers with the ethylene unit located at different positions of the polymer chains were systematically investigated. Our results demonstrated that absorption spectra and the HOMO and LUMO energy levels of polymers could be tuned by varying the position of the ethynylene unit in the polymer chains. Photovoltaic devices based on polymer/PC₇₁BM blend films spin coated from chloroform and dichlorobenzene solutions were investigated. For all four polymers, open circuit voltages (V_oc) higher than 0.8 V were obtained. P4 , with ethynylene unit between BTZ and thiophene, shows the best performance among these four polymers, with a V_oc of 0.94 V, a J_sc of 4.2 mA/cm², an FF of 0.40, and a PCE of 1.6%. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Synthesis and characterization of X-shaped oligo(para-phenylene)derivatives functionalized with fluorene ethynylene

<正>A series of linear and X-shaped oligo(para-phenylene) derivatives functionalized with fluorene ethynylenes 1,3 and 4 were synthesized through sequent Sonogashira coupling and Suzuki-Miyaura reaction in high yield.The electron-donating group-OCH_3 and electron-withdrawing counterparts-CF_3 were introduced to tune the spectra properties of compounds 3 and 4.The detail investigation of their photophysical properties in solution and film indicated that the introduction of both -OCH_3 and -CF_3 makes maximum emission distinct red-shift in comparison with parent compound 1,but the latter more prominently.     

Metal Cluster Terminated “Molecular Wires”

The gold complexes Au(C≡CC₆H₄C≡CC₆H₄Me)(PPh₃) (3) and {Au(PPh₃)}₂(μ-C≡CC₆H₄C≡CC₆H₄C≡CC₆H₄C≡C) (6), prepared from the reaction of AuCl(PPh₃) with the corresponding terminal or trimethylsilyl protected alkynes, react readily with Ru₃(CO)₁₀(μ-dppm) to afford phenylene ethynylene derivatives featuring the Ru₃(μ-AuPPh₃)(μ-C₂R)(CO)₇ cluster “end-caps”. The hydrido cluster Ru₃(μ-H)(μ-C₂C₆H₄C≡CC₆H₄Me)(CO)₇ (4a) has also been obtained. There are significant differences in the absorption spectra of the organic precursors, the gold complexes and the clusters indicate a mixing of electronic states between the cluster and phenylene ethynylene moieties, while the presence of the Ru₃ and in particular Ru₃(μ-AuPPh₃) cluster end-caps leads to a quenching of the phenylene ethynylene centred emission. The crystallographically determined structures of 3, 4a and Ru₃(μ-AuPPh₃) (μ-C₂C₆H₄C≡CC₆H₄Me)(CO)₇ (4b) are reported.Dedicated to Professor B.F.G. Johnson, one of the pioneers of cluster chemistry, in recognition of his outstanding contributions to the field.     

聚苯硫醚/尼龙6共混物界面对结晶行为的影响

高分子作为材料时 ,其力学性能受其结晶形态的影响 ,而其结晶形态与其结晶行为有关 .结晶性聚合物共混物中结晶组分由于第二组分存在 ,改变了结晶组分在熔体时的化学与物理环境 .因此 ,其结晶组分的结晶行为不仅取决于两组分在熔体时的相容性 ,而且与第二组分是否起到异相晶核作用和 /或两组分间界面是否诱导成核作用有关 ,从而影响共混物中结晶组分的结晶行为 ,导致共混物力学性能的改变[1～ 4] .在ＰＰＳ/ＰＡ6共混物中 ,由于ＰＰＳ的熔点和熔体结晶温度都比ＰＡ6的高 ,共混物熔体降温结晶ＰＰＳ是在ＰＡ6熔体存在下发生结晶 ,而ＰＡ6是在…