双酚A型环氧树脂多孔微球

双酚Ａ型环氧树脂多孔微球杨振忠许元泽俞浩赵得禄（中国科学院化学研究所高分子物理开放实验室北京１０００８０）关键词多孔微球，双酚Ａ环氧树脂，相反转技术微米级高分子多孔微球在生物医学、电子、印刷、信息业等方面具有重要作用．然而，通常的乳液聚合，悬浮聚合...     

空心微球气体总量抽样测量误差分析

 间接驱动内爆靶丸由外层CH涂层，内层玻璃球壳和内部充入的气体组成。当玻璃球外涂CH后，球内的气体只能抽检而没有无损测量方法。在大量实验和数据基础上，研究了液滴法制备空心玻璃微球气体渗透系数的差异和分布，利用数理统计方法对实验数据进行了分析和处理，计算了空心玻璃微球对氘气渗透系数的误差，微球预充气挑选方案产生的误差及分布。最后根据现在的抽样测量方案计算了误判的概率。     

分散聚合法制备单分散聚苯乙烯微球

以苯乙烯为单体,偶氮二异丁腈为引发剂,聚乙烯吡咯烷酮为分散稳定剂,在乙醇/水的极性反应体系中,使用分散聚合法制备了聚苯乙烯(PS)微球。研究了制备工艺对微球分子量等远程结构参数的影响。研究结果表明:在适合微球形成的单体用量、引发剂和分散稳定剂的浓度、反应温度、时间和乙醇/水的比例等参数下,克服了以往存在的粒径不均匀、分子量较低、微球表面圆整光洁度较低和产率偏低等主要问题,制备了粒径在1.5~3μm之间、粒径分布1.05~1.08、分子量80×104左右、最高得率达97%、球体表面光洁、球形对称均匀且相互不粘连的单分散PS微球。     

Approaches to Improve Therapeutic Efficacy of Biodegradable PLA/PLGA Microspheres: A Review

This review aims to provide a comprehensive overview about various innovative strategies that have been employed by recent researchers to overcome with the shortcomings associated with traditional microspheres. Essentially, optimization strategies from structural aspects have been widely investigated to improve the properties (e.g., enhanced hydrophilicity, reduced initial burst release, etc.) of the pristine microspheres. These include bulk alteration, surface modification as well as the formation of sophisticated microsphere design such as core-shell structures. Other than that, various microencapsulation techniques and novel technologies such as spray drying, supercritical fluid technique, membrane, and microfluidics emulsification also have been explored in this review. Additionally, the impact of formulation-related aspects on the drug encapsulation efficiency, particles size and particles size distribution during double emulsification method will also be discussed and reviewed extensively based on the recent literatures reported.     

介孔空心球状WC微球结构与晶相形成机理

采用喷雾干燥微球化处理-气固反应法制备了介孔空心球状WC微球，应用扫描电子显微镜(SEM)对微球的形貌变化进行了表征。结果表明，介孔空心球状结构是逐步形成的。其中，空心球状结构形成于前驱体微球化处理过程中，介孔结构形成于空心微球还原碳化过程中。在与样品制备工艺条件相同的情况下，采用原位X射线衍射技术(in situ XRD)对样品的晶相演变规律进行了监测。结果表明，样品在CO/CO₂气氛中进行还原碳化时，当温度缓慢而连续上升到750 ℃时，其晶相变化遵循AMT → WO₃ → WO₂ → W₂C → WC规律;当采用“阶跃式”升温，即温度缓慢而连续上升到400 ℃，然后再快速上升到750 ℃，并在750 ℃下进行还原碳化时，其晶相变化规律为AMT → WO₃ → WO₂ → WC。这说明，样品的晶相演变不仅与还原碳化温度和时间有关，而且与升温方式和升温速率有关。     

Hollow Cancrinite Zeolite Spheres in situ Transformed from Fly Ash Cenosphere

A novel hollow microsphere structure with cancrinite zeolite grown from the shell of fly ash cenosphere has been successfully prepared through in situ transformation in vapor phase; the orientation and morphology of cancrinite can be greatly improved by adding tetrapropylammonium hydrate into the synthetic system.     

Morphological investigations of crosslinked polystyrene microspheres by seeded polymerization

 Crosslinked polystyrene microspheres with novel surface and inner morphologies were synthesized by seeded polymerization following a seed-swelling method, using uncrosslinked polystyrene microspheres as seeds and a mixture of toluene, styrene (St), and divinylbenzene (DVB) as the swelling agent. With the increasing toluene/ (St+DVB) ratio, the crosslinked particles changed from smooth-surfaced spheres to deformed spheres with dimples or heavy dents at the surface. A single hole inside the spherical particles was produced at low St/DVB ratio, while higher St/DVB ratios gave irregular dented or dimpled particles. Ultrathin cross-section observation by TEM revealed a non-uniformly crosslinked inner structure. Received: 20 January 1998 Accepted: 14 April 1998     

溶剂热微乳法合成CdS微米球

CdS microspheres were prepared by a hydrothermal microemulsion method in cyclohexane/Triton X-100/pentanol/water at 180℃. The as-prepared samples were characterized by X-ray diffraction analysis, transmission electron microscopy, electron diffraction, energy diffraction X-ray analysis and photoluminescence spectra. It was found that CdS microspheres with diameter of 1.5-2.5μm were aggregated by nanocrystals. The formation mechanism was proposed.     

Adsorption of trypsin onto styrene-2-hydroxyethyl methacrylate copolymer microspheres and its enzymatic activity

Effects of the surface hydrophilicity of styrene-2-hydroxyethyl methacrylate (S-HEMA) copolymer microspheres on the adsorption immobilization of trypsin and on its enzymatic activity were discussed. In the case of a polystyrene (PS) microsphere, the amount of adsorption was large, whereas the enzymatic activity of the adsorbed trypsin was low. On the other hand, in the case of an S-HEMA copolymer microsphere whose HEMA content was 10 mole %, the maximum specific activity of trypsin adsorbed was nearly equal to that of free trypsin, although the amount of adsorption decreased to about 65 % of that in PS. Accordingly, total activity, which is the product of the amount of adsorption and the specific activity, could be enhanced by controlling the surface hydrophilicity of the microsphere.Part LXXXVII of the series Studies on Suspension and Emulsion.     

单分散亚微米级磁性微球的合成

以磁性氧化铁胶体粒子为种子粒子，采用吸附－溶胀法，进行苯乙烯－丙烯酸－二乙烯基苯的乳液聚合，制备亚微米级磁性高分了微球。研究了分散介质、丙烯酸、种子粒子、苯乙烯和ＰＨ调节剂等因素对聚合行为和磁性微球的影响，成功地合成了平均粒径为０．１３和０．２７μｍ、单分散性很好的磁性微球。