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以水热方法制备具有多级纳米结构的In2S3空心微球. 通过对不同反应时间产物的跟踪表征, 证明微球中空结构的形成归因于Ostwald ripening机理. 空心微球的壳层由In2S3的纳米粒子或纳米片组成, In2S3空心球的紫外可见光谱蓝移以及荧光光谱在约385 nm的强发射和364 nm的弱发射, 均显示了纳米尺度In2S3晶体的量子局限效应. 以不同的氨基酸作为晶体生长修饰剂, 可以选择性地制备不同表面形貌的In2S3空心微球, 显示了氨基酸的不同功能团在In2S3晶体生长过程中对表面形貌的控制作用. 相似文献
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《离子交换与吸附》2016,(5)
以壳聚糖(CS)和β-环糊精(β-CD)为原料,制备了壳聚糖接枝β-环糊精聚合物(CS-g-CD),然后以三聚磷酸钠(TPP)为交联剂,通过静电自组装的方法得到了聚合物空心微球,并以5-氟尿嘧啶(5-FU)为模型药物,研究了聚合物空心微球对药物的负载性能。利用红外光谱(FT-IR)、元素分析、X-射线衍射(XRD)表征了聚合物的结构和组成,激光粒度仪和透射电子显微镜(TEM)表征了聚合物微球的粒径及形貌。通过紫外可见分光光度计研究了微球对药物的载药量和包封率。结果表明,得到的微球呈现较为规则的空心结构,粒径在300~350nm左右,分散性较好,对药物载药量和包封率较高。 相似文献
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针对高效制备单分散聚合物纳米水凝胶微球手段欠缺问题,我们发展了一种新型的纳米水凝胶微球制备新技术——回流沉淀聚合技术,与以往的沉淀聚合及蒸馏沉淀聚合相比,该方法效率更高、普适性更强、操作更简单,适合高效制备单分散的纳米水凝胶微球及其复合微球.通过考察制备聚甲基丙烯酸微球过程中的反应时间、固含量、交联剂含量、混合溶剂比例等影响因素,成功制备了形态可控、尺寸均一、水中分散性良好的聚甲基丙烯酸纳米水凝胶微球,并给出了微球形态控制的基本规律.通过该技术制备的纳米水凝胶微球及其复合微球将被广泛用于生物医用材料中. 相似文献
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建立了采用异相成核和可控水解相结合的方法制备由纳米纤维构建的聚合物微球的新方法.根据多取代卞叉山梨醇(TM6)对聚己二酸丁二酯(PBA)的异相成核作用以及结晶形态的影响,采用两种乳液溶剂挥发法、并在聚合物溶液中加入成核剂TM6制备了PBA微球,研究了成核剂含量对PBA微球在酶促降解之后形态变化的影响.研究结果表明,二次乳液溶剂挥发法可以制备具有多孔结构的PBA微球,这种多孔结构有利于酶溶液进入到微球内部,促进PBA微球的均匀水解,最终获得由PBA纳米纤维构建的微球.当TM6的含量为3 wt%时,采用二次乳液溶剂挥发法制备的PBA微球,经过5 h酶促降解处理,可以得到表面和内部由PBA纳米纤维均匀组成的微球.进一步的细胞实验表明,微球的纳米纤维结构,有利于MG-63细胞在聚合物微球上的黏附、铺展和向内生长. 相似文献
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Hollow structure microspheres with composite polymeric-Laponite shells were prepared by electrostatic self-assembly of Laponite on the polymeric hollow microspheres in this work. The multilayer hydrophilic core/hydrophobic shell polymer latex particles containing carboxyl groups inside were first synthesized via seeded emulsion polymerization, followed by alkali treatment, generating polymeric hollow microspheres. Then, polyethyleneimine (PEI) and Laponite were alternately electrostatic adsorbed on the prepared polymeric hollow microspheres to form polymeric-Laponite composite hollow microspheres. It was indicated that the morphology of alkali-treated microspheres could be tuned through simply altering the dosage of alkali used in the post-treatment process. Along with the increasing of the coating layers, the zeta potential of microspheres absorbed PEI or Laponite approximately tended to be constant respectively, and the thickness of Laponite layer around the hollow microspheres increased clearly, getting more uniform and homogenous. Furthermore, the corresponding polymeric-Laponite hollow microspheres showed high pressure resistance ability compared to the polymeric hollow microspheres. 相似文献
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Synthesis and utilization of monodisperse hollow polymeric particles in photonic crystals 总被引:3,自引:0,他引:3
We developed a process to fabricate 150-700 nm monodisperse polymer particles with 100-500 nm hollow cores. These hollow particles were fabricated via dispersion polymerization to synthesize a polymer shell around monodisperse SiO(2) particles. The SiO(2) cores were then removed by HF etching to produce monodisperse hollow polymeric particle shells. The hollow core size and the polymer shell thickness, can be easily varied over significant size ranges. These hollow polymeric particles are sufficiently monodisperse that upon centrifugation from ethanol they form well-ordered close-packed colloidal crystals that diffract light. After the surfaces are functionalized with sulfonates, these particles self-assemble into crystalline colloidal arrays in deionized water. This synthetic method can also be used to create monodisperse particles with complex and unusual morphologies. For example, we synthesized hollow particles containing two concentric-independent, spherical polymer shells, and hollow silica particles which contain a central spherical silica core. In addition, these hollow spheres can be used as template microreactors. For example, we were able to fabricate monodisperse polymer spheres containing high concentrations of magnetic nanospheres formed by direct precipitation within the hollow cores. 相似文献
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Utilizing Reversible Interactions in Polymeric Nanoparticles To Generate Hollow Metal–Organic Nanoparticles 下载免费PDF全文
Longyu Li Dr. Conghui Yuan Dongming Zhou Dr. Alexander E. Ribbe Prof. Kevin R. Kittilstved Prof. S. Thayumanavan 《Angewandte Chemie (International ed. in English)》2015,54(44):12991-12995
The use of reversible linkers in polymers has been of interest mainly for biomedical applications. Herein, we present a novel strategy to utilize reversible interactions in polymeric nanoparticles to generate hollow metal–organic nanoparticles (MOPs). These hollow MOPs are synthesized from self‐assembled polymeric nanoparticles using a simple metal–comonomer exchange process in a single step. The control over the size of the polymer precursor particles translates into a straightforward opportunity for controlling MOP sizes. The shell thickness of the MOPs could be easily tuned by the concentration of metal ions in solution. The underlying mechanism for the formation of these hollow MOPs has been proposed. Evidence for the generality of the method is provided by its application to a variety of metal ions with different coordination geometries. 相似文献
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模板法制备复合中空微球 总被引:3,自引:1,他引:2
本文报道以一种商品化的聚苯乙烯中空球为模板, 采用溶胀聚合技术合成了具有IPN(Inter-Penetrating Network)结构的复合中空球; 对其中的一种高分子网络进行化学改性引入所需官能团, 制得带有羧基的聚合物凝胶中空球; 利用凝胶诱导生长特性, 成功制得聚合物复合中空球. 此方法无需去除模板就可批量制备各种复合功能中空球. 相似文献
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Susanne Blomberg Sofia Ostberg Eva Harth Anton W. Bosman Brooke Van Horn Craig J. Hawker 《Journal of polymer science. Part A, Polymer chemistry》2002,40(9):1309-1320
Surface‐initiated living free‐radical polymerization is employed in a multistep procedure to prepare hollow polymeric nanocapsules. Initially, trichlorosilyl‐substituted alkoxyamine initiating groups are attached to the surface silanol groups of silica nanoparticles. This surface layer of initiating groups is then used to grow functionalized linear chains leading to a core–shell morphology. The choice of functional groups is governed by their ability to undergo facile crosslinking reactions, with both active ester and benzocyclobutene groups being examined. Under either chemical or thermal conditions, the reaction of these functionalities gives a crosslinked polymeric shell that is covalently attached to, and surrounds, the central silica core. Removal of the silica core with HF then gives the hollow polymeric nanocapsules, which are stable under solvent dissolution and thermal treatment because of their crosslinked structure. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1309–1320, 2002 相似文献
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Preparation of monodisperse thermo-sensitive poly(N-isopropylacrylamide) hollow microcapsules 总被引:1,自引:0,他引:1
We successfully developed a novel and simple method for preparation of monodisperse thermo-sensitive poly(N-isopropylacrylamide) (PNIPAM) hollow microcapsules at the interface of water-in-oil (W/O) single emulsions at a temperature below the lower critical solution temperature (LCST) of PNIPAM. The prepared PNIPAM microcapsules are featured with hollow structures and thin membranes, high monodispersity, excellent reversible thermo-sensitivity and fast response to environmental temperature. This approach exhibits great interests in preparing monodisperse thermo-sensitive microcapsules for encapsulating bioactive materials or drugs requiring mild encapsulation conditions, because of the flexibility in choosing substances being dissolved in the aqueous phase. The preparation methodology demonstrated in this study provides a unique approach for preparing monodisperse hollow polymeric microcapsules with W/O single emulsions. 相似文献
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Sasidharan M Gunawardhana N Inoue M Yusa S Yoshio M Nakashima K 《Chemical communications (Cambridge, England)》2012,48(26):3200-3202
An efficient and simple protocol for synthesis of novel La(2)O(3) hollow nanospheres of size about 30 ± 2 nm using polymeric micelles is reported. The La(2)O(3) hollow nanospheres exhibit high charge capacity and cycling performance in lithium-ion rechargeable batteries (LIBs), which was scrutinized for the first time among the rare-earth oxides. 相似文献
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静电纺丝是一种制备纳米尺度连续长丝的技术,采用静电纺丝技术高效可控地构筑微纳米中空结构材料备受关注.本文综述了通过静电纺丝技术制备聚合物中空纤维和中空微球的研究进展,展望了其在不同功能材料领域的发展前景. 相似文献
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V. N. Pavlyuchenko O. V. Sorochinskaya O. N. Primachenko N. A. Byrdina S. S. Ivanchev M. Skrifvars 《Journal of polymer science. Part A, Polymer chemistry》2004,42(9):2225-2234
A method is described for the preparation of cationic latices comprising submicron hollow particles for a possible application as a thermally stable polymeric pigment in coatings or pigmented compositions on the basis of thermosetting polymers cured at temperatures up to 170–190 °C. The method is based on the deposition of melamine–formaldehyde resin in the form of cationic colloid onto anionic hollow particles resulting in the recharging of anionic hollow particles and the formation of an outer melamine shell, which provides thermal stability of the hollow particles at curing and application of pigmented coatings and compositions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2225–2234, 2004 相似文献