From Polymeric Nanoparticles to Dye-containing Photonic Crystals:Synthesis,Self-assembling,Optical Features, Possible Applications

1 Results Self-assembling of monodisperse polymeric nanoparticles is a perspective method of obtaining photonic crystalline materials for optoelectronics,telecommunication industry and optosensorics.For tuning optical characteristics of photonic crystals it is advisable to functionalize nanoparticles by dyes absorbing or emitting light in the vicinity of the photonic band gap,which position depends on the nanoparticle diameter.To prepare monodisperse nanoparticles with the dye-functionalyzed surface emu...     

聚氨酯/ACR复合材料的制备及表征

以表面功能化的聚丙烯酸酯类复合微球(ACR)、聚己二酸乙二醇酯(PEA)、甲苯二异氰酸酯(TDI-100)、扩链剂(MOCA)为原料,采用预聚法制备出聚氨酯/核壳高分子微球(PU/ACR)新型复合材料。结果表明,当复合微球的添加量(质量分数)为2%~4%时,PU/ACR复合材料的综合力学性能最好;DSC分析表明,该复合微球的加入影响了聚氨酯的微相分离。     

石蜡聚苯乙烯微球的制备

用悬浮聚合法制备石蜡聚苯乙烯微球．研究了合成过程中搅拌器的位置、搅拌速度、升温速度和反应时间等对微球粒径分布及其产率的影响．结果表明：搅拌器桨叶上平面与液面相平时有利于合成粒径小、分布均匀的石蜡聚苯乙烯微球；搅拌器最佳搅拌速度为275～330rpm；缓慢升温更有利于合成粒径小、分布均匀的石蜡聚苯乙烯微球；最佳反应时间为4．0～4．5h．     

微米级单分散苯乙烯-甲基丙烯酸共聚物微球的制备

以聚乙烯吡咯烷酮为分散稳定剂、偶氮二异丁腈为引发剂、醇或醇/水混合物为分散介质，用分散共聚合方法制备了微米级苯乙烯-甲基丙烯酸共聚物微球。研究了功能单体用量、介质的溶解度参数、分散剂用量及温度对共聚反应速率、转化率、共聚物微球的粒径和粒径分布的影响。结果表明，功能单体用量增加，聚合速率变慢，粒径增大；介质的溶解度参数增大，聚合速率增大，转化率提高，粒径减小；分散剂用量增大，聚合速率及转化率的变化不大，粒径减小；反应温度升高，聚合速率和转化率提高，粒径增大，粒径分布变宽。     

铝酸酯在粉煤灰微珠表面上偶联机理的研究

提出了铝酸酯偶联剂在粉煤灰微珠表面的单分子层模型，并用红外光谱、扫描电子显微镜等分析，证实了铝酸酯与粉煤灰微珠是通过化学键实现界面偶联的。     

MMA-EDMA聚合物微球型和包覆硅胶型填料的制备与色谱性能

以Methyl methacrylate(MMA)和Ethylene dimethacrylate(EDMA)作为单体制备了多孔聚合物微球型(PG)和硅胶基质聚合物包覆型填料(PCSG).经电子显微镜、元素分析、尺寸排阻色谱和反相液相色谱对多孔聚合物微球粒径、硅胶基质聚合物包覆程度、交联剂添加对填料微孔构造的影响、非极性和极性化合物的色谱保留行为进行了评价和讨论.结果显示:PG和PCSG填料制备过程中形成了与C18填料不同的微孔结构;PG填料的大微孔体积Vb最大,PCSG填料小微孔体积Va最大.PG和PCSG填料的小微孔体积Va的不同导致填料表面具有相同的MMA高分子链却表现出不同的疏水性能;大微孔体积Vb的存在使填料对大体积芳香族化合物分离表现出了与C18填料不同的立体选择性.PG和PCSG填料因其表面残留有相同的MMA高分子链,使其对极性芳香族化合物表现出了相似的色谱保留行为.PCSG填料的柱效能介于C18和PG填料之间.     

制备条件对P(NIPAM-co-St)微球粒径的影响

以N-异丙基丙烯酰胺(NIPAM)、苯乙烯(St)为单体采用无皂乳液聚合法制备P(NIPAM-co-St)微球。在制备过程中,综合考察了反应时间、引发剂用量、相比、搅拌速度4个因素对P(NIPAM-co-St)微球的粒径的影响。实验结果表明,增加引发剂量、延长反应时间对减小微球粒径的影响最大,而增加相比则起着相反的作用;当搅拌速度在600 r/min,引发剂量为4%,相比为2.5%,反应时间为12 h的单分散性都比较好。     

Facile and environment friendly synthesis of hierarchical BiOCl flowery microspheres with remarkable photocatalytic properties

A facile and environment friendly approach to synthesis of unique hierarchical BiOC1 flowery micro- spheres （FMs） using a biodegradable surfactant polyvinyl alcohol （PVA） was reported herein for the first time. Com- pared to the BiOC1 nanosheets synthesized in the absence of PVA, hierarchical BLOC1 FMs consist of large amounts of interwoven polycrystalline nanosheets that assemble into a porous flowery structure. The formation mechanism of the hierarchical BiOC1 FMs was also proposed, whereby PVA was believed to play a key role in the crystal growth and the formation of the final microstructures. Compared with TiO2- P25 and BiOC1 nanosheets, hierarchical BiOC1 FMs dis- played remarkably enhanced photocatalytic activity, and 20 mg of BiOC1 FMs could completely degrade 50 mL of methyl orange solution （20 rag/L） within 30 min under UV- light irradiation. According to the comprehensive analysis, it can be concluded that the larger specific surface area, porosity, suitable band gap, and the enhanced light absorp- tion capacity may contribute to the remarkably enhanced photocatalytic activity. This facile and green approach to fabricating hierarchical BiOC1 FMs would give vital clues to develop new route for synthesizing other hierarchical structured materials.     

A novel injectable fibroblasts-porous PDLLA microspheres/collagen gel composite for soft-tissue augmentation

This study designed a novel porous PDLLA microspheres/collagen gel composite combined with fibroblasts as the injectable dermal filler for soft-tissue augmentation. The low degradation rate of porous PDLLA microspheres and seed cells were introduced in the system to achieve the filling volume stability and stronger regeneration activity. Biodegradable PDLLA porous microspheres were prepared by an improved water-in-oil-in-water double emulsion solvent evaporation method. The combine of fibroblasts with porous microspheres was observed through co-culture of cells with microspheres, SEM (scanning electron microscope) and fluorescent staining technology. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, the hemolysis test and histocompatibility experiment indicated that the composite had satisfactory biocompatibility in vitro and in vivo. In the animal studies, the composite was implanted into the subcutaneous part of the rats’ back through sterile needles. The collagen was metabolized within 30 days, meanwhile, fibroblasts-porous PDLLA microspheres served as scaffold structure and seed cells which promote new connective tissue formation. The histopathological studies demonstrate that the fibroblasts-porous PDLLA microspheres/collagen gel composite group could create larger amount of supportive structure than PDLLA porous microspheres/collagen gel composite group. All the results indicate that fibroblasts-porous PDLLA microspheres/collagen gel composite may have great clinical application in soft-tissue augmentation with its excellent biocompatibility, regeneration activity and stable long-term filling ability.     

硬炭微球的制备及其储锂性能研究

以二乙烯基苯(DVB)为交联剂、偶氮二异丁腈(AIBN)为引发剂、聚乙烯吡咯烷酮(PVP)为模版剂,通过自组装,制备聚苯乙烯微球。经过氧化和高温炭化转换成硬炭微球。考察了硬炭微球作为锂离子负极材料的电化学性能。结果表明硬炭微球的首次放电比容量为505 mA·h/g,40次循环后保持在304 mA·h/g。