Designing Semipermeable Hydrogel Shells with Controlled Thickness through Internal Osmosis in Triple-Emulsion Droplets

Hydrogel shells that compartmentalize the water core from the aqueous surrounding provide molecular selectivity on size and charge in transmembrane transport. It is highly demanding to produce thin hydrogel shells to minimize diffusion length and maximize core volume. Here, internal osmosis in water-in-oil-in-water-in-oil (W/O/W/O) triple-emulsion droplets is used to produce thin hydrogel shells enclosing a large water core. The triple-emulsion droplets are prepared to have an ultrathin middle oil layer using a capillary microfluidic device. The innermost water droplet has a higher osmolarity than the outer water layer containing photopolymerizable hydrogel precursors, which pumps water from the outer layer to the core through the ultrathin oil layer by the osmosis. Therefore, the outer layer gets thinner and hydrogel precursors are enriched while the size of the triple-emulsion droplets remains unchanged. Through photopolymerization of precursors and phase transfer from oil to water, hydrogel shells enclosing water core are produced in the water environment; the oil layer is ruptured for molecular exchange through the shells. The thickness and composition of the hydrogel shells are precisely controllable by the osmotic conditions. The shells show a high permeation rate due to the thinness as well as controlled cut-off threshold of permeation for neutral and charged molecules.     

石墨烯负载纳米二硫化钴的制备及其在锂离子电池方面的应用研究

采用二次水热法将纳米二硫化钴负载于石墨烯上,并通过结构表征和电化学性能测试,探讨了纳米二硫化钴/石墨烯材料作为锂离子电池负极的性能。电容量测试结果表明：在电流密度为100 mA/g条件下,二硫化钴/石墨烯复合材料的首周充放电容量分别为1 610 mA·h/g和774 mA·h/g,测算出的库伦效率为48.1%;循环性能测试结果表明：经过50次循环测算后的复合材料的放电比容量为302 mA·h/g,容量保持率为33.4%;倍率性能测试结果表明：当电流密度回复到100 mA/g时,复合材料的比容量恢复至550 mA·h/g。实验制备的纳米二硫化钴/石墨烯复合材料在锂电池负极的应用上表现出了优异的循环性能和倍率性能。     

改性纳米碳酸钙用于硅酮胶挤出性研究

采用碳化法合成纳米碳酸钙,在反应过程中,调整反应起始温度合成不同晶型大小的纳米碳酸钙。通过透射电镜（TEM）、激光粒度仪对碳酸钙的物相、形貌、粒度进行分析,将改性纳米碳酸钙应用于硅酮胶基料制备及挤出性研究,分析改性纳米碳酸钙的颗粒大小、分散性、流变性能及表面改性剂对挤出性的影响。结果表明：粒径介于50~90 nm,屈服值介于66.4~148.9 Pa,黏度介于0.5~0.75 mPa·s,硬脂酸钠与LH-2、LH-3两种包覆剂进行复配改性的纳米碳酸钙用于硅酮胶基料具有较好的挤出性能。     

Microencapsulation of camellia oil to maintain thermal and oxidative stability with focus on protective mechanism

Camellia oil (CO) microcapsules were developed using chitosan–soybean protein isolate (CS-SPI) complexes as wall materials and transglutaminase (TGase) as the cross-linking agent. Results indicated that CO/SPI under the ratio of 1:2 exhibited the highest microencapsulation efficiency and yield, possessing the best encapsulation effect. Morphology observation showed that CO microcapsules were intact, compact and nearly spherical. The microencapsulated CO exhibited the improved thermal resistance and significantly lower peroxide values after 3 days storage, demonstrating that the produced microcapsule was a promising way to maintain the thermal and oxidative stability of camellia oil. It could be found evidence from FTIR, which indicated that covalent cross-linking and hydrogen bonding might be involved among wall materials, and physical interactions between the core and wall materials. Therefore, the produced CO microcapsules could be an effective way to protect camellia oil, which was helpful for improving the processing and storage qualities of camellia oil.     

彩色纳米碳酸钙的研制

以纳米碳酸钙中试装置为平台,通过控温碳化、加热湿法染色、加热湿法改性和分散处理,制得了具有良好一次粒子形态的彩色纳米碳酸钙产品。激光粒度仪测试表明,彩色纳米碳酸钙产品的D₅₀约为350 nm,具有粒度分布均匀、分布范围窄等特点。产品在空气中长期放置不氧化、不褪色,说明具有良好的化学稳定性。亲水性实验表明,彩色纳米碳酸钙产品在水中长时间放置、反复搅拌,仍然不沉降、不掉色,说明染色和活化都是牢固的。以酸性媒染蓝黑B染料和硬酯酸为例,分析了纳米碳酸钙的湿法染色和湿法活化机理,并且探讨了硬酯酸分子、染色剂分子和碳酸钙颗粒之间的化学交联作用。     

壳聚糖包裹广藿香精油微胶囊的制备及表征

采用复合凝聚法,以广藿香精油为芯材,壳聚糖（CTS）和阿拉伯胶（GA）为壁材,制备了广藿香精油微胶囊。采用扫描电子显微镜（SEM）、激光粒度仪、傅里叶红外光谱（FT-IR）等对微胶囊进行表征。结果表明,当乳化剂用量为质量分数1%,芯壁质量比为1∶2,乳化转速为2 500r/min,复凝pH为5,固化剂用量为1.5g时,微胶囊包封率和载药量最佳,微胶囊球形规则、分散性好,平均粒径为10.5μm。     

广藿香油微胶囊化学交联法对棉织物的功能整理

以2D树脂作交联剂,以广藿香油微胶囊对棉织物进行防皱抗菌功能整理。运用扫描电镜及红外光谱对织物进行表征,并对织物抑菌耐水洗性能、缓释性能、防皱性能及甲醛含量进行了测试。结果表明,微胶囊通过2D树脂的桥梁连接作用被固着在棉织物上,提高了微胶囊织物防皱抗菌耐洗涤效果。