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21.
Fei Li Jianzhong Yang Yang Qin 《Journal of polymer science. Part A, Polymer chemistry》2013,51(16):3339-3350
We report the synthesis and characterization of a polythiophene block copolymer (P4) selectively functionalized with diaminopyrimidine moieties and a thymine tethered fullerene derivative (F1). Self‐assembly between P4 and F1 through “three‐point” complementary hydrogen bonding is studied by 1H NMR spectroscopy and differential scanning calorimetry. A large Stern‐Volmer constant (KSV) of 1.2 × 105 M?1 is observed from fluorescence quenching experiments, revealing strong complexation between these two components. Solar cells employing P4 and F1 at different weight ratios as active layers are fabricated and tested; corresponding thin film morphologies are studied in detail by optical imaging and atomic force microscopy. Correlations between polymer complex structures, film morphologies, and device performance are discussed. Thermal stability of benchmark poly(3‐hexylthiophene) bulk heterojunction solar cells is found to be improved by the addition of a few weight percent of P4/F1 complexes as compatibilizers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3339–3350 相似文献
22.
应用小角X射线散射技术(SAXS)对两亲嵌段共聚物聚苯乙烯聚丙烯酸(PS-b-PAA)胶束形貌的温度影响进行了原位表征.SAXS结果表明:随着水含量的增加,粒子尺寸相应增加;对于水含量10%的PS_(3000)-b-PAA_(5000)胶束溶液,发现了明显的SAXS双峰现象;双峰的位置不随着温度的变化而改变,但是peak 1和peak 2的相对强度随着温度发生了减弱和增强的交错变化;相邻的SAXS双峰说明在PS_(3000)-b-PAA_(5000)胶束溶液中最初形成的粒子尺寸并不是均匀的,主要分为尺寸极其相近的两种球形粒子;随着温度的升高,粒径大小不同的两种粒子存在着一种消融和生长的过程,并且保持着一个相同的归一化动态平衡速率. 相似文献
23.
Jooung-Hyun Jo Hyun-Cheol Ko Byeong-Woo Kim Hyun Park In-won Lee Ho-Hwan Chun 《Composite Interfaces》2016,23(8):797-805
AbstractMarine fouling can be a serious problem in the shipping industry, since it increases the surface roughness of the hull and hence its frictional resistance to its movement through water. Antifouling paint can be defined as preventing the attachment of marine organisms onto surfaces. However, the most commonly used antifouling coating which is the tributyltin-based self-polishing copolymer causes the severe pollution of marine environment. Ammonium salt-based paints include tertiary amines as biocides which have effective biocidal and biodegradable properties without accumulation in the sea environment. However, ammonium salt-based coatings were too sensitive to seawater and became swollen. In this study, polyurethane-acrylic copolymers were synthesized by radical polymerization. These hybrid materials were found to form core–shell structures in aqueous media. Synthesis and properties of copolymers were investigated by Fourier transform-infrared spectrometer, proton-nuclear magnetic resonance, transmission electron microscopy, and dynamic light scattering. The polishing rate of self-polishing copolymer was determined from the reduction in dry film thickness after artificial seawater immersion under a dynamic condition. 相似文献
24.
25.
嵌段共聚物溶致液晶相中水的2H-NMR动力学分析 总被引:2,自引:1,他引:2
采用D2O 的2H-NMR线型和弛豫分析了PEO-PPO-PEO/D2O/对二甲苯体系的层状和六角液晶相的动力学行为. 通过实验测得了两个不同体系的自旋 晶格弛豫时间T1、自旋-自旋弛豫时间T2和2H-NMR 谱. 2H-NMR 谱均为具有四极劈裂的粉末谱线型,且在谱图的中心,βLD=54.7°时存在一个倒峰. 倒峰的出现直接表明引起体系中弛豫的主要动力学过程处于极窄化区域. 采用NMR弛豫模型,通过调节动力学参数,使理论模拟的2H-NMR谱、弛豫时间、倒峰的大小与实验的对应量相吻合,求得了体系的动力学参数. 相似文献
26.
以马来酸酐和丙烯酰胺为功能单体,N,N-亚甲基双丙烯酰胺为交联剂,过硫酸铵为引发剂合成了马来酸酐、丙烯酰胺共聚物吸附剂P(MA-AM)。用傅里叶变换红外光谱(FTIR)和热重分析对共聚物进行了表征,并采用电感耦合等离子体原子发射光谱(ICP-AES)法研究了共聚物的吸附性能和选择性;结果表明,在pH 3.5时,P(MA-AM)对Fe3+具有很高的选择性,1 h达吸附平衡,其饱和吸附量为78.81 mg·g-1;Fe3+的吸附过程符合准二级反应动力学模型,吸附模型可以用Freundlich等温吸附来描述,该吸附为吸热过程。 相似文献
27.
K. Ogura T. Hattori M. Hirata M. Asano M. Yoshida M. Tamada H. Omichi N. Nagaoka H. Kubota R. Katakai 《Radiation measurements》1995,25(1-4):159-162
Several types of copolymers of CR-39 were prepared to find its usefulness as a nuclear track detector of high sensitivity. Track responses of these copolymers were investigated by irradiating energetic ions from proton through Ar. The copolymer of CR-39 monomer with N-isopropylacrylamide (NIPAAm) shows higher sensitivity than that of pure CR-39 for low LET particles such as protons. Preliminary results are reported for the track responses of copolymers (CR-39/NIPAAm) with various contents of NIPAAm as well as the etching properties. 相似文献
28.
The mechanical and damping properties of blends of ethylene-vinyl acetate rubber (VA content >40% wt) (EVM)/ethylene-propylene-diene copolymer (EPDM) and EVM/nitrile butadiene rubber (NBR), both with 1.4 phr BIPB (bis (tert-butyl peroxy isopropyl) benzene) as curing agent, were investigated by dynamic mechanical analysis (DMA). The effect of added polyvinyl chloride (PVC), amido donor N-cyclohexyl-2-benzothiazole sulfonamide (CZ), and dicumyl peroxide (DCP) as a substitute curing agent, on the damping and mechanical properties of both rubber blends were studied. The results showed that in EVM/EPDM/PVC blends, EPDM was immiscible with EVM and could not expand the damping range of EVM at low temperature. PVC was miscible with EVM and dramatically improved the damping property of EVM at high temperature while keeping good mechanical performance. In EVM/NBR/PVC blends, PVC was partially miscible with EVM/NBR blends and remarkably widened the effective damping temperature range (EDTR) from 41.1°C for EVM/NBR to 62.4°C. Curing agents BIPB and DCP had a similar influence on EVM/EPDM blends. DCP, however, dramatically raised the height of tan δ peak of EVM/NBR = 80/20 and expanded its EDTR to 64.9°C. CZ had no obvious influence on the EVM/EPDM blends cured with BIPB. However, a small content of CZ enlarged the tan δ peak of EVM/NBR = 80/20 in both height and width, but at the cost of a deterioration of mechanical performance. 相似文献
29.
The self-assembly of diblock copolymers confined around one square-shaped particle is studied systematically within two-dimensional self-consistent field theory(SCFT).In this model,we assume that the thin block copolymer film is confined in the vicinity of a square-shaped particle by a homopolymer melt,which is equivalent to the poor solvents.Multiple sequences of square-shaped particle-induced copolymer aggregates with different shapes and self-assembled internal morphologies are predicted as functions of the particle size,the structural portion of the copolymer,and the volume fraction of the copolymer.A rich variety of aggregates are found with complex internal self-assembled morphologies including complex structures of the vesicle,with one or several inverted micelle surrounded by the outer monolayer with the particle confined in the core.These results demonstrate that the assemblies of diblock copolymers formed around the square-shaped particle in poor solvents are of immediate interest to the assembly of copolymer and the morphology of biomembrane in the confined environment,as well as to the transitions of vesicles to micelles. 相似文献
30.
本文分别用JEOL FX-90Q和Bruker AM-300波谱仪测定了氢化聚丁二烯和氢化丁苯共聚物的1H,13C-NMR谱,得到了分辨率较高的谱图和新的结构信息。借助DEPT技术确定了各谱带的CH或CH2类型。利用Grant-Paul和Lindeman-Adams介绍的化学位移经验计算公式,考虑苯基对α、β和γ碳原子的影响,计算了各种三单元序列中有关碳原子的化学位移。对脂肪碳部分的28组谱带重新进行了归属。化学位移计算值与实测值基本相符,并得到了不同组成的模型聚合物13C-NMR谱的各谱带强度变化规律的验证。 相似文献