苯乙烯／马来酸酐共聚物的氢键诱导液晶化——单氢键方式的SLCP复？…

合成了侧链含苯甲酸的苯乙烯／马来酸单酯共聚物（ＭＥ－ＳＭＡ）和４－苯乙烯基吡啶（４ＳＺ）。以ＴＨＦ为溶剂，制备了以ＭＥ－ＳＭＡ为质子给体，４ＳＺ为质子受体的氢键复合物。用ＤＳＣ和偏光显微镜（ＰＯＭ）研究两者复合前后的液晶行为。结果表明形成的氢键复合物在２０３℃￣３３４℃呈现向列相液晶态，并用ＩＲ证实了分子间氢键的存在。     

N—异丙基丙烯酰胺／丙烯酸十八酯共聚物水溶液胶束及相分？…

合成了Ｎ－异丙基丙烯酰胺（ＮＩＰＡＭ）和丙烯酸十八酯（ＯＤＡ）的共聚物，利用荧光探针和滴重法研究了ＮＩＰＡＭ－烘聚物在水溶液中的胶束形成过程，同时还利用荧光探针法研究了共聚物水溶液在温度升高时出现的ＬＣＳＴ现象，表明该高分子在温度升高时存在着相分离现象，利用Ｌ－Ｂ技术测量共聚物不溶单分子膜的π－Ａ曲线，发现随着温度升高共聚物的单分子膜越来越凝聚的反常现象，这从另一个侧面证实了共聚物ＮＩＰＡＭＯＤＡ     

苯乙烯/马来酸酐共聚物的氢键诱导液晶化——单氢键方式的SLCP复合物的合成和表征

合成了侧链含苯甲酸的苯乙烯／马来酸单酯共聚物（ＭＥ－ＳＭＡ）和４－苯乙烯基吡啶（４ＳＺ）。以ＴＨＦ为溶剂，制备了以ＭＥ－ＳＭＡ为质子给体，４ＳＺ为质子受体的氢键复合物。用ＤＳＣ和偏光显微镜（ＰＯＭ）研究两者复合前后的液晶行为。结果表明形成的氢键复合物在２０３℃～３３４℃呈现向列相液晶态，并用ＩＲ证实了分子间氢键的存在。     

聚酰胺1010／聚乙烯－马来酸酐接枝共聚物共混物力学和热学性能研究

为了表明马来酸酐接枝聚烯烃后对聚酰胺的相容作用，本文研究了聚酰胺１０１０（ＰＡ１０１０）／聚乙烯－马来酸酐接枝共聚物（ＰＥ－ｇ－ＭＡＨ）共混物在不同ＭＡＨ接枝量下的结晶性与力学性能。研究表明，ＭＡＨ的存在导致ＰＥ－ｇ－ＭＡＨ－ｃｏ－ＰＡ１０１０共聚物的形成，而该共聚物在标题共混物中起着相容剂的作用。共混物的结晶性能变化显示了共混组分间存在一定程度的混溶性。在一定的ＭＡＨ含量内，标题共混物具有协同效应。     

聚丙烯酸酯无皂水溶胶阻尼涂料动态力学性能的研究

用分步溶液聚合法合成了两种丙烯酸酯共聚物的共混物［Ｐ（ＢＡ－ＨＥＭＡ－ＡＡ）／Ｐ（ＭＭＡ－ＨＥＭＡ－ＡＡ）Ａ］，制成无皂水溶胶，加入交联剂配成涂料。两种共聚物既可相互贯穿缠结，又可通过交联剂交联，使涂膜同时具有物理交联和化学交联。用动态力学分析法（ＤＭＡ）、扭辫分析法（ＴＢＡ）考察了涂膜的动态力学性能，表明涂膜具有ＩＰＮ结构，并有良好的阻尼性能。     

丙烯酰胺－丙烯酸甲酯－2－丙烯酰胺基－2－甲基丙磺酸共聚物的合成及表征

以丙烯酰胺（ＡＭ），丙烯酸甲酯（ＭＡ）和２－丙烯酰胺基－２－甲基丙磺酸（ＡＭＰＳ）为原料，通过水溶液共聚，合成了一种新的三元共聚物。研究了影响共聚反应的因素，并对其结构进行了表征。     

苯乙烯/马来酸酐共聚物氢键复合物的合成与表征

以４－苯乙烯基吡啶（４ＳＺ）为质子受体，准链链含苯甲酸的苯乙烯／马来酸单楷共聚物（ＭＥ－ＳＭＡ）为质子供体，四氢呋喃为溶剂，制备高分子氢链复合物。ＤＳＣ和ＰＯＭ的结果表明该氢链复合物在１４６￣２０４℃呈现向列相液晶态。ＩＲ结果证实了羧基和吡啶环的分子间氢键代替了羧基间的分子间氢链。     

基团转移嵌段共聚研究

本文采用双官能团引发剂和负离子型催化剂进行了甲基丙烯酸甲酯和甲基丙烯酸Ｃ７～９酯的基团转移嵌段共聚．讨论了温度、单体投料方式、引发剂－催化剂浓度比及单体浓度对聚合反应的影响，认为当两段反应温度分别为８５℃和２５℃时，引发剂浓度［Ｉ］＝１．３５×１０－２ｍｏｌ／Ｌ，催化剂引发剂浓度比［Ｃａｔ］／［Ｉ］＝０．１２６，以活性较低的Ｃ７～９ＭＡ为第一嵌段单体，有利于Ｃ７～９ＭＡ和ＭＭＡ的嵌段共聚．测定了嵌段共聚物的热形变温度；用ＧＰＣ对嵌段共聚物的相对分子质量及分布进行了表征，结合ＩＲ、１ＨＮＭＲ和热形变温度分析，证明所得到的为ＰＭＭＡ－ＰＣ７～９ＭＡ－ＰＭＭＡ均相三嵌段共聚物．     

PVC/PBD-b-PMMA共混体系相容性的研究

采用ＤＭＡ和ＴＥＭ系统研究了聚丁二烯－聚甲基丙烯酸甲酯的嵌段共聚物（ＰＢＤ－ｂ－ＰＭＭＡ）与聚氯乙烯（ＰＶＣ）共混体系的相容性问题。结果表明：ＰＶＣ／ＰＢＤ－ｂ－ＰＭＭＡ共混体系具有部分相溶性。相容的程度与共混体系的组成、组分聚合物的分子量以及共聚物中ＰＢＤ和ＰＭＭＡ嵌段的比例密切相关。     

含有机硅三元多嵌段共聚物的研究5.含有机硅三元多嵌段共聚物的形态结构

利用ＤＭＡ，ＴＥＭ和ＳＡＸＳ对ＰＳＦ－ＰＤＭＳ－ＰＨＳｎ，ＰＳＦ－ＰＤＭＳ－ＰＨＥｎ，ＰＰＯ－ＰＤＭＳ－ＰＨＳｎ和ＰＨＳ－ＰＤＭＳ－ＰＢＥｎ四种三元多嵌段共聚物的形态结构进行了研究，结果表明，不同三元多嵌段共聚物中三种链段的相互作用情况不同，其动态力学性能和形态结构有很大差异，并与嵌段共聚物微相分离的几种基本形态不同，特别是通过ＴＥＭ在ＰＳＦ－ＰＤＭＳ－ＰＨＳｎ和ＰＰＯ－ＰＤＭＳ－ＰＨＳｎ中观察到清晰的互容界面相。     

Morphology control of poly(3‐hexylthiophene)‐b‐poly(ethylene oxide) block copolymer by solvent blending

The use of mixed solvents provided an effective way to control the self‐assembly behavior and photophysical properties of a conjugated rod–coil block copolymer, poly(3‐hexylthiophene)‐b‐poly(ethylene oxide) (P3HT‐b‐PEO). It was shown that the balance between the π–π stacking of the P3HT and microphase separation of the copolymer could be dynamically controlled and shifted by solvent blending. Depending on the mixed solvent ratio (i.e., chloroform/methanol, anisole/chloroform, or anisole/methanol), the copolymer chains experienced different kinetic pathways, yielding a series of nanostructures such as disordered wormlike pattern, densely packed nanofibrils, and isolated nanofibrils. With the varying solvent selectivity, the P3HT‐b‐PEO chains displayed a hybrid photophysical property depending on the competition between intrachain and interchain excitonic coupling, resulting in the transformation between J‐ and H‐aggregation. Overall, this work offered an effective way to demonstrate the correlation and transformation between π–π stacking of P3HT and microphase separation, and how the conformation of P3HT chains influenced the photophysical properties of the copolymer during solvent blending. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 544–551     

Glycerol-induced swollen lamellar phases with siloxane copolymers

Phase behavior is established for a block copolymer polyethyleneoxide-b-dimethylsiloxane-polyethylenoxide (EO)(15)-(PDMS)(15)-(EO)(15) (IM-22) a in glycerol/water mixed solvent. In water alone, the block copolymer forms biphasic micellar/lamellar (L(1)/L(alpha)) systems over the range 10-70 wt%, with single L(alpha)-phases between 70-90 wt%. Strong solvent effects on the phase behavior were noted. For example, using a mixed 60:40 vol% glycerol/water solvent, the single L(alpha)-phase region appears at much lower concentrations, only 20 wt% IM-22, as compared to the biphasic L(1)/L(alpha) system observed in water alone. This interesting observation of L(alpha)-phase swelling on addition of glycerol may be explained by a decrease in attraction between the bilayers, as it is also found that in this mixed glycerol/water solvent there is a close refractive index matching with IM-22. Rheological measurements show the L(alpha)-phases with added glycerol have low shear moduli. The influence of added ionic surfactant sodium dodecylsulfate (SDS) on these swollen IM-22 L(alpha)-phases was studied. Small-angle X-ray scattering (SAXS) indicated the interlamellar distance d remains essentially constant up to 3 mM SDS, and then decreases with increasing SDS content. This weak effect is consistent with the fact that the L(alpha)-phases are most swollen when the mixed solvent contains 60 vol% glycerol. The results suggest that glycerol/water solvent mixtures can be used to tune the refractive index of the background solvent, modifying DLVO-type interactions, and causing significant effects on the phase stability of simple block-copolymer systems.     

Influence of Mixed Common Solvent on the Co-assembled Morphology of PS-b-PEO and CdS Quantum Dots

The hybrid structures of polystyrene-b-poly(ethylene oxide)(PS-b-PEO) block copolymer and inorganic nanoparticles with good stability and biocompatibility have potential applications in drug delivery and bioimaging. Spherical co-assemblies of PS120-b-PEO318 and oleylamine-capped Cd S quantum dots(QDs) are produced successfully in this work by adding water to a mixed common solvent, such as N,N-dimethylmethanamide(DMF)/chloroform, DMF/tetrahydrofuran(THF), or DMF/toluene. The energy dispersive X-ray(EDX) spectrum indicates that QDs are located at the interface between the core and shell of the spherical co-assemblies. The co-assembly process during water addition is traced by transmission electron microscopy(TEM) and turbidity measurement. Spherical co-assemblies are formed through budding from bilayers of the block copolymer and QDs. The morphology of the co-assemblies is related to the miscibility of the QD-dispersing solvents with water and the morphology changes from a spherical to a vesicle-like structure with DMF/toluene. Increasing THF content in the mixed solvent causes morphological transitions from spherical co-assemblies to multi-branched cylinders and micelles where QDs are located in the central core. Increasing chloroform content yields vesicle-like structures with protruding rods on the surface. The mechanism of the morphological transitions is also discussed in detail.     

Quantitative SAXS analysis of the P123/water/ethanol ternary phase diagram

The ternary phase diagram of the amphiphilic triblock copolymer PEO-PPO-PEO ((EO)(20)(PO)(70)(EO)(20) commercialized under the generic name P123), water, and ethanol has been investigated at constant temperature (T = 23 degrees C) by small-angle X-ray scattering (SAXS). The microstructure resulting from the self-assembly of the PEO-PPO-PEO block copolymer varies from micelles in solution to various types of liquid crystalline phases such as cubic, 3D hexagonal close packed spheres (HCPS), 2D hexagonal, and lamellar when the concentration of the polymer is increased. In the isotropic liquid phase, the micellar structural parameters are obtained as a function of the water-ethanol ratio and block copolymer concentration by fitting the scattering data to a model involving core-shell form factor and a hard sphere structure factor of interaction. The micellar core, the aggregation number, and the hard sphere interaction radius decrease when increasing the ethanol/water ratio in the mixed solvent. We show that the fraction of ethanol present in the core is responsible for the swelling of the PPO blocks. In the different liquid crystalline phases, structural parameters such as lattice spacing, interfacial area of PEO block, and aggregation number are also evaluated. In addition to classical phases such as lamellar, 2D hexagonal, and liquid isotropic phases, we have observed a two-phase region in which cubic Fm3m and P6(3)mmc (hexagonally close packing of spheres (HCPS)) phases coexist. This appears at 30% (w/w) of P123 in pure water and with 5% (w/w) of ethanol. At 10% (w/w) ethanol, only the HCPS phase remains present.     

Effect of water content on the size and membrane thickness of polystyrene-block-poly(ethylene oxide) vesicles

The asymmetric amphiphilic block copolymer polystyrene962-block-poly(ethylene oxide)227(PS962-b-PEO227) canforms micelles with N, N-dimethylformamide(DMF) as co-solvent and water as selected solvent, and when the water content of the mixed solvent is higher than 4.5 wt%, the vesicle will be dominated. This work finds that once vesicles are formed in the DMF-water mixed solvent, the vesicle size and membrane thickness can be tuned by further increasing water content. As the water fraction elevated from 4.8 wt% to 13.0 wt%, the vesicle size dercreases from 246 nm to 150 nm, while the membrane thickness increases from 28 nm to 42 nm. In addition, the block copolymer packing and the free energy are analyzed as the vesicle size becomes small and the membrane becomes thick.     

4-乙烯基吡啶与丙烯酰胺共聚合的研究

以过硫酸钾为引发剂 ,采用溶液自由基共聚合方法 ,实现了丙烯酰胺 (AM)与 4 乙烯基吡啶 (4 VP)的共聚合 .通过详细研究共溶剂体系、单体总浓度、反应温度、反应时间及引发剂量对共聚合过程中转化率和分子量的影响 ,从而确定了适宜的共溶剂体系和最佳的工艺条件 .用紫外分光光度法测得了共聚物的组成 .用Kelen Tudos方法 ,求得 4 乙烯基吡啶 (4 VP)和丙烯酰胺 (AM)单体的竞聚率 ,r4 VP =0 6 4 4 ,rAM =0 371.最后通过FTIR和1 3C NMR表征共聚物的结构并验证了共聚物的组成 .     

Study of molecular motion of block copolymers in solution by high-resolution proton magnetic resonance

Molecular motions of hydrophobic–hydrophilic water-soluble block copolymers in solution were investigated by high-resolution proton magnetic resonance (NMR). Samples studied include block copolymers of polystyrene–poly(ethylene oxide), polybutadiene–poly(ethylene oxide), and poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide). NMR measurements were carried out varying molecular weight, temperature, and solvent composition. For AB copolymers of polystyrene and poly(ethylene oxide), two peaks caused by the phenyl protons of low-molecular-weight (M?_n = 3,300) copolymer were clearly resolved in D₂O at 100°C, but the phenyl proton peaks of high-molecular-weight (M?_n = 13,500 and 36,000) copolymers were too broad to observe in the same solvent, even at 100°C. It is concluded that polystyrene blocks are more mobile in low-molecular-weight copolymer in water than in high-molecular-weight copolymer in the same solvent because the molecular weight of the polystyrene block of the low-molecular-weight copolymer is itself small. In the mixed solvent D₂O and deuterated tetrahydrofuran (THF-d₈), two peaks caused by the phenyl protons of the high-molecular-weight (M?_n = 36,000) copolymer were clearly resolved at 67°C. It is thought that the molecular motions of the polystyrene blocks are activated by the interaction between these blocks and THF in the mixed solvent.     

Particulation of hyperbranched aromatic biopolyesters self-organized by solvent transformation in ionic liquids

Hyperbranched copolymers were prepared by the heat transesterification of 4-hydroxycinnamic acid (4HCA) and 3,4-dihydroxycinnamic acid (DHCA) with a high 4HCA composition dissolved in trifluoroacetic acid (TFA). The nanoparticles were formed after two homogeneous copolymer solutions were mixed in DMF and TFA, which are both good solvents for the copolymer P(4HCA-co-DHCA). We confirmed that the driving force for particulation was solvent interactions that produce ion pairs, which elevate the polarity of the solvent too much to solubilize the copolymers.     

Effect of binary block‐selective solvents on self‐assembly of ABA triblock copolymer in dilute solution

We have studied the self‐assembly of the ABA triblock copolymer (P4VP‐b‐PS‐b‐P4VP) in dilute solution by using binary block‐selective solvents, that is, water and methanol. The triblock copolymer was first dissolved in dioxane to form a homogeneous solution. Subsequently, a given volume of selective solvent was added slowly to the solution to induce self‐assembly of the copolymer. It was found that the copolymer (P4VP₄₃‐b‐PS₃₆₆‐b‐P4VP₄₃) tended to form spherical aggregate or bilayer structure when we used methanol or water as the single selective solvent, respectively. However, the aggregates with various nanostructures were obtained by using mixtures of water and methanol as the block‐selective solvents. The aggregate structure changed from sphere to rod, vesicle, and then to bilayer by changing water content in the block‐selective solvent from 0 to 100%. Moreover, it was found that the vesicle size could be well controlled by changing the copolymer content in the solution. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1536–1545, 2008     

Synthesis,surface accumulation,and micellar properties of amphiphilic block copolymers

Amphiphilic block copolymers, i.e., poly(methyl methacrylate)-b-poly(2-dimethylethylammoniumethyl methacrylate), were synthesized by the reaction between two prepolymers. Carboxyl-terminated poly(methyl methacrylate) and hydroxyl-terminated poly(2-dimethylaminoethyl methacrylate) were prepared by radical polymerization of the corresponding monomers in the presence of thioglycolic acid and 2-mercaptoethanol as a chain transfer agent, respectively. Two condensation methods, i.e., DCC and the acid chloride method, were used for the reactions of these prepolymers. The subsequent quarternization produced the amphiphilic block copolymers. Surface property of poly(methyl methacrylate) films containing this amphiphilic block copolymer was examined by measuring contact angles for water. The addition of only 0.5 wt% of the block copolymer was sufficient to make poly(methyl methacrylate) surfaces hydrophilic. The block copolymer formed a polymeric micelle in acetone–water mixed solvent.