空心玻璃微球/聚酰亚胺复合薄膜的制备及性能表征

以功能性聚酰亚胺为基体,空心玻璃微球为填料,采用原位聚合法合成聚酰胺酸溶液,流延成膜,制备了不同含量的空心玻璃微球/聚酰亚胺复合薄膜,研究了不同空心玻璃微球含量对复合薄膜力学性能、介电性能和热稳定性能的影响。结果表明,空心玻璃微球的加入能够保持复合薄膜的热稳定性,其玻璃化转变温度在363℃左右;复合薄膜的弹性模量处于上升的趋势,当空心玻璃微球的质量分数为3%左右时拉伸强度达到最大;同时随着空心玻璃微球含量的增加,击穿强度依然保持在很高的数值;空心玻璃微球含量增加时,复合薄膜的介电常数出现降低的趋势,当含量达到9%时,薄膜的介电常数可以降低70%左右,同时介电损耗因数在0.05以下,表现为较为优异的低介电性能。     

聚酰亚胺微球掺杂纳米二氧化硅的制备及表征

以4,4’-二氨基二苯醚和均苯四甲酸二酐作为单体,采用非水乳液体系,加入纳米二氧化硅,制备聚酰亚胺微球.本文研究了纳米二氧化硅对聚酰亚胺热性能以及球形形貌、粒径大小的影响.通过红外分析(IR)、热重(TGA)、示差扫描(DSC)、电镜(SEM)、粒度等手段对其进行表征.表征结果显示当纳米SiO2的加入量为0.2g时,此时改性后的聚酰亚胺微球球形形貌良好,粒子表面光滑,呈单分散性,粒径为28.4μm,且失重率为5％时,其在氧气气氛下分解温度高达508℃,呈现高耐热性.     

复合无机填料耐温增效聚酰亚胺泡沫的制备和性能

针对市场不同行业领域特别是锂电池行业,对泡沫材料提出的更高的高温隔热性能,为了使得聚酰亚胺泡沫能够实现高温下的隔热性能,利用复合无机填料增效聚酰亚胺泡沫的耐温性能,研究了空心玻璃微球与可膨胀蛭石的不同比例、无机填料不同添加量以及不同密度聚酰亚胺泡沫对其高温隔热性能的影响,通过600℃的加热台测试泡沫背面的冷面温度,研究发现,聚酰亚胺泡沫的发泡倍率在5～10倍,添加的空心玻璃微球和可膨胀蛭石的质量是泡沫质量的50%,其中空心玻璃微球占无机物质量的20%,得到的聚酰亚胺泡沫在常温下具有较低的导热系数,并且在高温下的隔热性能优异。     

单分散聚酰亚胺微球的形貌分析和表征

研以均苯四甲酸二酐(PMDA)和4,4-二氨基二苯醚(ODA)为单体,采用反相非水乳液法制备聚酰亚胺(PI)微球.在两相比-定时,研究了复配乳化剂的浓度对PI徽球形貌及单体含量对微球粒径的影响.产物通过红外,热重(TG),扫描电镜(SEM),粒度分析手段进行表征.SEM表明:单体浓度20%,复配乳化剂含量7.88%时,...     

微囊化载药高分子微球制备方法研究进展

本文综述了各种微囊化制备微球的方法和原理，并对微囊化微球技术的研究最新进展及其在纳米微球，磁性高分子微球、智能微球制备上的应用作了介绍。     

纳米淀粉微球的制备及其在生物医药中的应用

综述了纳米淀粉微球的3种制备方法:物理法、化学法和反相微乳液法,介绍了反相微乳液法制备纳米淀粉微球的原理、制备步骤、淀粉微球性质及其在生物医药领域的应用。     

碳微球的研究进展

从碳微球的制备方法着手,综述了各方法的制备原理、原料、影响因素以及所得碳微球的结构性能和形貌特征,并归纳了各方法的优缺点,得出了溶剂热法、化学气相沉积法和模板法3种相对有效的制备方法,由于溶剂热法的突出优点,在碳微球的多种制备方法中优势凸显,将成为未来制备碳微球的主要方法。详细评述了不同结构和性能的碳微球在各个领域的应用,深入开发碳微球的性能和拓展其应用领域将会成为今后的研究重点;进一步讨论了碳微球的结构对其性质和应用的影响,通过设计碳微球的结构来改变其性质,是碳微球制备研究领域未来的发展方向。     

酚醛树脂基炭微球结构调控与功能化制备研究进展

炭微球具有化学稳定性好、电导率优良、比表面积大、孔结构丰富等优点,在吸附、催化等领域具有广阔的应用前景,引起了研究人员的广泛关注。酚醛基炭微球以酚醛树脂为前体,经高温炭化制备而成,这种制备方法工艺简单、对设备要求低、产率高,而且通过调整反应物和反应条件可实现对炭微球结构和功能性的精细调控,从而更好地满足实际应用的需求。概述了酚醛基炭微球的最新研究进展,分为小粒径炭微球制备、多孔炭微球制备和功能化炭微球制备三个方面,并介绍了酚醛基炭微球在储能、吸附和电催化领域的应用,最后对其未来发展方向进行了展望。     

酚醛树脂基炭微球结构调控与功能化制备研究进展

炭微球具有化学稳定性好、电导率优良、比表面积大、孔结构丰富等优点,在吸附、催化等领域具有广阔的应用前景,引起了研究人员的广泛关注。酚醛基炭微球以酚醛树脂为前体,经高温炭化制备而成,这种制备方法工艺简单、对设备要求低、产率高,而且通过调整反应物和反应条件可实现对炭微球结构和功能性的精细调控,从而更好地满足实际应用的需求。概述了酚醛基炭微球的最新研究进展,分为小粒径炭微球制备、多孔炭微球制备和功能化炭微球制备三个方面,并介绍了酚醛基炭微球在储能、吸附和电催化领域的应用,最后对其未来发展方向进行了展望。     

单分散聚合物微球的制备及功能化研究进展

综述了单分散聚合物微球常用的制备方法(乳液聚合法、种子聚合法、分散聚合法、沉淀聚合法、悬浮聚合法和膜乳化法等),介绍了单分散聚合物微球的功能化研究进展,包括磁性微球、多孔微球、温度/pH响应微球、阳离子微球以及微球官能团化等等。最后提出了多种聚合方法的相互结合是制备功能性单分散聚合物微球的一大趋势,开发多功能的单分散聚合物微球、实现批量生产是其近期的重点研究方向。     

聚吡咯/海藻酸钙导电微球的制备与表征

用乳液法成功制备出形貌规则的海藻酸钙微球,以该微球为"模板",合成出电导率为3.82S/cm的聚吡咯/海藻酸钙微球,探讨了其形成机理。用扫描电镜(SEM)对海藻酸钙微球及聚吡咯/海藻酸钙微球形貌进行了表征,发现搅拌速度为2200r/min时,海藻酸钙微球形貌最好,直径约为7μm,聚吡咯/海藻酸钙微球直径约为10μm。用傅立叶变换红外光谱(FTIR)和X射线衍射光谱(XRD)对产物的结构进行了表征,结果表明,海藻酸钙微球已经成功掺杂到聚吡咯中;聚吡咯/海藻酸钙微球的XRD衍射峰强度明显高于纯聚吡咯的衍射峰强度。     

壳聚糖固化单宁微球的制备及其吸附性能

5 g单宁酸与10 g壳聚糖微球在100 mL pH=7的溶液中反应6 h,再用0.06 mol/L环氧氯丙烷在pH=10,50℃反应4 h制得壳聚糖固化单宁微球,每克壳聚糖微球固载单宁量为0.27 g。采用扫描电镜和红外光谱对微球进行了表征,考察了微球的溶胀性能及对金属离子的吸附性能。研究表明,通过此法制得的壳聚糖固化单宁微球具有表面粗糙,内部疏松多孔的结构。与壳聚糖微球相比,壳聚糖固化单宁微球在溶液中的溶胀性减小,在pH=5及9时,分别减小了63%和50%。对金属离子的吸附容量增大,对Cd2+的吸附容量从0.6 mmol/g提高到2.2 mmol/g,提高了2.66倍。     

Preparation and evaluation of poly(3‐hydroxybutyrate) microspheres containing bovine serum albumin for controlled release

The utility of the Poly(3‐hydroxybutyrate) (PHB) to encapsulate and control the release of bovine serum albumin (BSA), via microspheres, was investigated. Various preparing parameters, including polymer concentration in oil phase, emulsification concentration in external water phase, volume ratio of inner water phase to oil phase, and volume ratio of primary emulsion to external water phase were altered during the microspheres production. The effects of these changes on the morphological characteristics of the microspheres, size of the microspheres, drug loading, encapsulation efficiency, and drug release rates were examined. The diameter of the microspheres ranged from 6.9 to 20.3 μm and showed different degrees of porous structure depending on the different preparation parameters. The maximum and minimum BSA encapsulation efficiency within the polymeric microspheres were 69.8 and 7.5%, respectively, varying with preparation conditions. The controlled release characteristics of the microspheres for BSA were investigated in pH 7.4 media. The initial BSA burst release from 8.9 to 63.1% followed by constant slow release for 28 days was observed for BSA from BSA‐loaded microspheres and followed the Higuchi matrix model. So, the release behavior of microspheres showed the feasibility of BSA‐loaded microspheres as controlled release devices. Pristine BSA, pristine PHB microspheres, and BSA‐loaded microspheres were analyzed by Fourier transform infrared spectrophotometer, which indicated no interaction between BSA and PHB. Differential scanning calorimetry on BSA‐loaded microspheres indicated a molecular level dispersion of BSA in the microspheres. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

聚合物/SiO2核壳结构单分散微球的制备

聚合物/SiO2核壳结构单分散微球比聚合物微球具有更好的稳定性,有望在较高的温度和有机溶剂中得到使用.为了制备出这种微球,作为模板的聚合物微球首先进行表面胺化处理,然后正硅酸乙酯被诱导在其表层水解缩合从而形成SiO2壳层;采用扫描电子显微镜(SEM)、傅里叶红外光谱仪(FTIR)、激光粒度仪,烧蚀质量损失等手段分析表征...     

Preparation and thermal decomposition of PS/AG microspheres

PS/Ag microspheres were prepared by electroless silver plating on PS microspheres. SEM, EDS, and XRD approved the successful formation of silver coatings on PS microspheres. The thermogravimetric analysis was studied using a TGA system. The Ozawa and Coats-Redfern methods were exploited to calculate activation energy and determine thermal decomposition mechanism. The thermal decomposition mechanism of pure PS microspheres was also investigated to draw comparisons with the mechanism of PS/Ag microspheres. It has been found that the thermal decomposition mechanism of PS/Ag microspheres and PS microspheres were both A₂ model. The activation energy of PS microspheres and PS/Ag microspheres is 76.76 kJ/mol and 78.61 kJ/mol, respectively. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

松香基氨基化聚合物微球的制备及吸附性能

利用氨基硅烷偶联剂（KH-792）对松香基羟基化聚合物微球进行接枝改性,研究了反应温度、反应时间和KH-792用量对聚合物微球性能的影响。利用红外光谱（FTIR）、热重分析（TGA）、扫描电镜（SEM）和X-射线光电子能谱（XPS）对聚合物微球进行测试表征,利用电导滴定法测定了聚合物微球的氨基含量。探讨了不同氨基含量的聚合物微球对乙基紫的吸附作用。结果表明：成功制备了松香基氨基化聚合物微球,改性前后聚合物微球形态均无明显变化且球形及单分散性好,热稳定性高于松香基羟基化聚合物微球。较优制备条件为：KH-792用量为松香基羟基化聚合物微球质量的70%,在90℃下反应10h,聚合物微球氨基含量达到181μmol/g。当固液比为1 g/L,pH=9.5,在328 K下吸附5min时,微球对乙基紫的吸附量为57.02 mg/g。     

The preparation and forming mechanism of the red blood cell‐shaped microspheres via electrospraying

This article successfully prepared the red blood cell‐shaped microspheres via electrospraying. The polymer solution was comprised of polyether sulfone (PES) and dimethyl sulfoxide (DMSO), and the hydrophilic polyethylene glycol (PEG) was added to regulate and control the structure of the microspheres. When the solution concentration was 7.6 wt % and PES/PEG proportion was 10 : 5 while preparing microspheres, the shape and diameter of the microspheres was the most similar to that of erythrocyte. The results suggested that the forming mechanism of the red blood cell‐shaped microspheres be related to two aspects. One is that the microspheres had relatively weak mechanical strength because of the sponge pores internal nanostructure. The other is that the existence of residual solvents and water within the microspheres would dissolve the gel phase PES and then further weaken mechanical strength of the outer layer of the microspheres, which caused the structural changes on the top layer of the spheres, that is, the top layer collapsed, and the microspheres finally turned into the red blood cell‐shaped microspheres. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.     

Preparation of Chitosan and Water-Soluble Chitosan Microspheres via Spray-Drying Method to Lower Blood Lipids in Rats Fed with High-Fat Diets

This experiment aimed to investigate the effects of the chitosan (CTS) and water-soluble chitosan (WSC) microspheres on plasma lipids in male Sprague-Dawley rats fed with high-fat diets. CTS microspheres and WSC microspheres were prepared by the spray-drying technique. Scanning electron microscopy (SEM) micrographs showed that the microspheres were nearly spherical in shape. The mean size of CTS microspheres was 4.07 μm (varying from 1.50 to 7.21 μm) and of WSC microspheres was 2.00 μm (varying from 0.85 to 3.58 μm). The rats were classified into eight groups (n = 8) and were fed with high-fat diets for two weeks to establish the hyperlipidemic condition and were then treated with CTS microspheres and WSC microspheres, CTS and WSC for four weeks. The results showed that CTS and WSC microspheres reduced blood lipids and plasma viscosity and increased the serum superoxide dismutase (SOD) levels significantly. This study is the first report of the lipid-lowering effects of CTS and WSC microspheres. CTS and WSC microspheres were found to be more effective in improving hyperlipidemia in rats than common CTS and WSC.