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1.
接枝共聚物聚苯乙烯-g-聚氧乙烯的微相分离形态研究   总被引:2,自引:0,他引:2  
本文利用透射电子显微镜技术,以两性接校共聚物聚苯乙烯-g-聚氧乙烯为研究对象,研究了接枝共聚物的微相分离形态结构,发现聚苯乙烯-g-聚氧乙烯能形成微相分离结构,微区的形状和尺寸与共聚物的组成和侧链长度有关.文中还讨论了嵌段共聚物和接枝共聚物在形成微相分离结构时的共性和个性.  相似文献   

2.
在三异丁基铝催化下DL-丙交酯与2-氢-2-氧-1,3,2-二氧磷杂环己烷开环共聚,制备了一类新型水溶性共聚物P(LA-co-TMP)。用1HNMR、IR谱对其结构进行了表征,并研究了催化剂用量及不同单体配比对总转化率、共聚物组成及特性粘度的影响。  相似文献   

3.
接枝共聚物聚苯乙烯-g-聚氧乙烯的微相分离形态研究   总被引:3,自引:0,他引:3  
 本文利用透射电子显微镜技术,以两性接校共聚物聚苯乙烯-g-聚氧乙烯为研究对象,研究了接枝共聚物的微相分离形态结构,发现聚苯乙烯-g-聚氧乙烯能形成微相分离结构,微区的形状和尺寸与共聚物的组成和侧链长度有关.文中还讨论了嵌段共聚物和接枝共聚物在形成微相分离结构时的共性和个性.  相似文献   

4.
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。  相似文献   

5.
丙烯酸丁酯-苯乙烯-丙烯腈共聚物的结构与力学性能张会轩,韩业,张会良,冯之榴(吉林工学院化工系长春130012)(中国科学院长春应用化学研究所长春)关键词ASA,乳液聚合,粒子,力学性能丙烯酸丁酯-苯乙烯-丙烯腈共聚物(ASA)是两相结构,聚丙烯酸丁...  相似文献   

6.
采用热分析方法并配合红外光谱法,研究了四氟乙烯与六氟丙烯共聚物(FEP)的分子链结构和聚集态结构。发现FEP共聚物分子链结构是由共聚链段和均聚链段组成的。提出了共聚物的聚集态模型和热裂解、热氧化裂解机制,成功地解释了FEP共聚物的热行为、热稳定性和热氧化过程。  相似文献   

7.
张宏放  那辉 《应用化学》1996,13(1):58-61
应用一维电子密度相关函数方法,对含不同联苯结构的PEEKK-PEBEKK共聚物样品小角X射线散射(SAXS)去模糊强度分析计算表明:PEEKK-PEBEKK共聚物的聚集态结构明显地依赖于共聚物中联苯含量。当联苯含量nb=0.35时,积分不变量Q,长周期L,平均结晶片层厚d,电子密度差η_c-η_a和结晶度W_(c,x)值为最小,比表面积O_s为最大。  相似文献   

8.
尼龙-1010的聚集态结构   总被引:1,自引:0,他引:1  
用WAXD、DSC、方差-范围函数.密度测量等方法,研究了经不同热处理的尼龙-1010的聚集态结构.发现退火处理更有利于尼龙-1010结晶的生成和稳定,且尼龙-1010的结晶,有一个最佳的热处理温度.在该温度附近,尼龙-1010的结晶度和微晶尺寸里最大值.  相似文献   

9.
聚甲基丙烯酸甲酯接枝聚氧乙烯在甲苯中的聚集态结构   总被引:1,自引:0,他引:1  
两亲接枝共聚物;胶束;聚甲基丙烯酸甲酯接枝聚氧乙烯在甲苯中的聚集态结构  相似文献   

10.
苯乙烯-丁二烯-苯乙烯工嵌段共聚物/聚(苯乙烯-甲基丙烯酸盐)热塑性IPN中离子聚集结构的研究韦雨春,袁惠根,潘祖仁(浙江大学化工系杭州310027)关键词互穿聚合物网络,离子聚集,远红外光谱,X-光散射以苯乙烯-丁二烯-苯乙烯三嵌段共聚物(SBS)...  相似文献   

11.
We present a one-pot synthesis for well-defined nanostructured polymeric microparticles formed from block copolymers that could easily be adapted to commercial scale. We have utilized reversible addition-fragmentation chain transfer (RAFT) polymerization to prepare block copolymers in a dispersion polymerization in supercritical carbon dioxide, an efficient process which uses no additional solvents and hence is environmentally acceptable. We demonstrate that a wide range of monomer types, including methacrylates, acrylamides, and styrenics, can be utilized leading to block copolymer materials that are amphiphilic (e.g., poly(methyl methacrylate)-b-poly(N,N-dimethylacrylamide)) and/or mechanically diverse (e.g., poly(methyl methacrylate)-b-poly(N,N-dimethylaminoethylmethacrylate)). Interrogation of the internal structure of the microparticles reveals an array of nanoscale morphologies, including multilayered, curved cylindrical, and spherical domains. Surprisingly, control can also be exerted by changing the chemical nature of the constituent blocks and it is clear that selective CO(2) sorption must strongly influence the block copolymer phase behavior, resulting in kinetically trapped morphologies that are different from those conventionally observed for block copolymer thin films formed in absence of CO(2).  相似文献   

12.
Poly(isoprene-block-methyl methacrylate) (PI-b-PMMA) block copolymers with different block ratios have been used to generate nanostructures both in thin films and by nanostructuring a thermosetting epoxy system. Obtained morphologies have been analyzed in terms of atomic force microscopy. The nanostructuring of thin films was carried out by thermal and solvent vapor annealing, in which the copolymer films were exposed to acetone vapors, selective solvent for methyl methacrylate (PMMA) block. By solvent vapor annealing thin films of both copolymers self-assembled into a hexagonally packed cylindrical morphology. Thermal annealing was carried out above the glass transition temperature of both blocks, obtaining worm-like and lamellar morphologies, depending on the block ratio. One of the copolymers has also been used for nanostructuring an epoxy thermosetting system. Morphologies consisting of spherical-shaped PI domains dispersed in a continuous epoxy matrix in which PMMA remained miscible were obtained, independently of the copolymer amount.  相似文献   

13.
含氟丙烯酸酯共聚物制备超疏水表面及其形成机理的研究   总被引:7,自引:0,他引:7  
魏海洋  李欣欣  王康  贺文潇  韩哲文 《化学学报》2008,66(12):1470-1476
以丙烯酸全氟烷基乙基酯和甲基丙烯酸甲酯为共聚单体, 分别以用微乳液聚合法和溶液聚合法制备的无规共聚物和用可逆加成-断裂链转移制备的嵌段共聚物作为成膜共聚物, 并以1,1,2-三氟三氯乙烷作为溶剂, 采用溶剂挥发成膜法可以直接制备出超疏水膜, 聚合物膜对水的接触角可达160°. 改变聚合物结构和成膜条件, 探讨了该类超疏水膜的形成机理和影响因素. 发现膜的表面形貌和疏水性与共聚物的组成、结构、分子量以及成膜条件密切相关, 随着共聚物中氟含量的增大, 膜的表面形貌都趋于平滑; 而且, 无规共聚物比嵌段共聚物更易形成粗糙度好的膜; 同时, 较大的聚合物分子量和适宜的高的成膜温度都对形成粗糙结构有利.  相似文献   

14.
两亲性嵌段共聚物PS-b-PMAA的合成与胶束化行为研究   总被引:7,自引:2,他引:5  
华慢  杨伟  薛乔  陈明清  刘晓亚  杨成 《化学学报》2005,63(7):631-636
利用原子转移自由基聚合法(ATRP)得到了分子量可控、分子量分布接近1.1的聚苯乙烯-b-聚甲基丙烯酸叔丁酯(PS-b-PtBMA)嵌段共聚物, 进而在酸性条件下由水解反应得到了两亲性的聚苯乙烯-b-聚甲基丙烯酸 (PS-b-PMAA)嵌段共聚物.用GPC, FTIR和1H-NMR等对产物的分子量和组成进行了表征.使PS-b-PMAA在选择性溶剂中进行自组装, 通过激光光散射和透射电子显微镜研究了影响其胶束化行为的因素与胶束形态, 并初步探讨了胶束形成的机理, 发现通过控制嵌段共聚物的链段长度之比可得到空心球形的高分子胶束.  相似文献   

15.
The thermosensitive block copolymer poly(2-cinnamoylethyl methacrylate)-block-poly(N-isopropylacrylamide) (PCEMA-b-PNIPAAm) can form crew-cut aggregates with multiple morphologies under various micellization conditions. Spherical, rod-like, vesicular, lamellar aggregates, and large compound micelles were obtained from the block copolymers. The effects of different conditions, such as the copolymer composition, the nature of the common solvent, the initial copolymer concentrations, and the water content on the morphologies of the aggregates were studied in detail. The thermosensitive property of the aggregates was investigated through measuring the change of the dimension of the aggregates with changing the external temperature.  相似文献   

16.
The self-assembly induced by the photocontrolled/living radical polymerization mediated by 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl was performed for amphiphilic poly(methacrylic acid)-block-poly(alkyl methacrylate-random-methacrylic acid) containing ethyl, n-propyl, and n-butyl methacrylates in order to control the morphology based on the hydrophobic-hydrophilic balance. The morphology transformation from films to spherical vesicles via the transition was well-controlled by adjusting the ratio of the alkyl methacrylate unit to the methacrylic acid in the hydrophobic random copolymer block. The copolymers formed the respective morphologies at different ratios dependent on the alkyl chain length of the methacrylates; the ratio for the formation of the respective morphologies decreased as the alkyl chain length increased. The hydrophobic energy estimation of these copolymers demonstrated that the respective morphologies had definite hydrophobic energies independent of the alkyl chain length, indicating that the morphologies were determined only by the hydrophobic magnitude of the random copolymer block.  相似文献   

17.
We investigated the morphological transitions induced by alkyne/azide Huisgen 1,3‐dipolar cycloaddition reaction in a series of poly(ethylene oxide)‐block‐poly(n‐butyl methacrylate‐random‐propargyl methacrylate) (PEO‐b‐P(nBMA‐r‐PgMA)) diblock copolymers. Studies on the phase behavior of neat diblock copolymers revealed that the interactions between the PEO block and the terminal alkyne groups in the P(nBMA‐r‐PgMA) block significantly affected the miscibility between the two blocks and the crystallization of the PEO block. Phase‐mixed diblock copolymers underwent disorder‐to‐order transitions by blending with Rhodamine B azide and annealing at elevated temperatures. Different morphologies were achieved, not only by controlling the composition of the block copolymer but also by blending the diblock copolymer with different amount of azides. Microphase separated PEO‐b‐P(nBMA‐r‐PgMA) diblock copolymer also exhibited reactivity toward azides, and order‐to‐order transitions were observed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011  相似文献   

18.
Ye X  Yu X  Shi T  Sun Z  An L  Tong Z 《The journal of physical chemistry. B》2006,110(46):23578-23582
By using a combinatorial screening method based on the self-consistent field theory, we investigate the equilibrium morphologies of linear ABCBA and H-shaped (AB)(2)C(BA)(2) block copolymers in two dimensions. The triangle phase diagrams of both block copolymers are constructed by systematically varying the volume fractions of blocks A, B, and C. In this study, the interaction energies between species A, B, and C are set to be equal. Four different equilibrium morphologies are identified, i.e., the lamellar phase (LAM), the hexagonal lattice phase (HEX), the core-shell hexagonal lattice phase (CSH), and the two interpenetrating tetragonal lattice phase (TET2). For the linear ABCBA block copolymer, the reflection symmetry is observed in the phase diagram except for some special grid points, and most of grid points are occupied by LAM morphology. However, for the H-shaped (AB)(2)C(BA)(2) block copolymer, most of the grid points in the triangle phase diagram are occupied by CSH morphology, which is ascribed to the different chain architectures of the two block copolymers. These results may help in the design of block copolymers with different microstructures.  相似文献   

19.
By using a combinatorial screening method based on the self-consistent field theory (SCFT) for polymers, we have investigated the morphology of H-shaped ABC block copolymers (A2BC2) and compared them with those of the linear ABC block copolymers. By changing the ratios of the volume fractions of two A arms and two C arms, one can obtain block copolymers with different architectures ranging from linear block copolymer to H-shaped block copolymer. By systematically varying the volume fractions of block A, B, and C, the triangle phase diagrams of the H-shaped ABC block copolymer with equal interactions among the three species are constructed. In this study, we find four different morphologies (lamellar phase (LAM), hexagonal lattice phase (HEX), core-shell hexagonal lattice phase (CSH), and two interpenetrating tetragonal lattice (TET2)). Furthermore, the order-order transitions driven by architectural change are discussed.  相似文献   

20.
倪沛红 《高分子科学》2013,31(2):218-231
 Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-(N,N-dimethylamino)ethyl methacrylate] (PIB-b-PDMAEMA) and polyisobutylene-block-poly(metharylic acid) (PIB-b-PMAA), were synthesized via oxyanion-initiated polymerization, and their multiple self-assembly behaviors have been studied. An exo-olefin-terminated highly reactive polyisobutylene (HRPIB) was first changed to hydroxyl-terminated PIB (PIB-OH) via hydroboration-oxidation of C=C double bond in the chain end, and then reacted with KH to yield a potassium alcoholate of PIB (PIB-O-K+). PIB-O-K+ was immediately used as a macroinitiator to polymerize DMAEMA monomer, resulting in a cationic diblock copolymer PIB-b-PDMAEMA. With the similar synthesis procedure, the anionic diblock copolymer PIB-b-PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate (tBMA) and subsequent hydrolysis of tert-butyl ester groups in PtBMA block. The functional PIB and block copolymers have been fully characterized by 1H-NMR, FT-IR spectroscopy, and gel permeation chromatography (GPC). These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent. Transmission electron microscopy (TEM) images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles, vesicles with different particle sizes and cylindrical aggregates, depending on various factors including block copolymer composition, solvent polarity and pH value.  相似文献   

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