壳聚糖季铵盐/维生素E微胶囊的制备工艺研究

采用复凝聚法制备壳聚糖季铵盐/维生素E微胶囊。通过可拍摄数码生物显微镜观察整个微胶囊制备过程的形态,研究反应过程的工艺条件对微胶囊乳液的影响,得到工艺制备的最佳条件是:以吐温-80和司班-80(1:1)作为乳化剂,用量为0.6%,壁材浓度为1.1%,芯壁比为1:1.5,乳化搅拌速度为2000 r min-1;复凝聚反应pH为5.2～5.4,时间为30 min;交联固化pH为5.8～6.0,时间为150 min。得到的微胶囊粒径在5~10μm,产品的载药量23.4%,包封率为85.0%。     

单凝聚法制备酞菁铜颜料纳米微胶囊的研究

以聚乙烯吡咯烷酮(PVP)为壁材,通过单凝聚法制备酞菁酮颜料纳米微胶囊。结果表明,PVP质量、分离剂的加入方式以及搅拌速度等工艺条件对微胶囊粒径和分散性有影响,其中较佳的制备条件为:芯壁比为1.07,分离剂Na_2SO_4按10 m L/min的速度加入,搅拌速度为1 000 r/min。此时,可以制得粒径分布窄,平均粒径小于100 nm的酞菁酮微胶囊,分散体系稳定性良好。     

半胱氨酸盐酸盐-乙基纤维素微胶囊的制备研究

选用半胱氨酸盐酸盐作为芯材,乙基纤维素作为壁材,采用有机溶剂蒸发技术制备微胶囊。通过单因素实验和正交分析得到最佳实验条件:壁材浓度为1%,海藻酸钠保护液浓度为0.5%,乙酸乙酯做溶剂,油水相比为5∶1,搅拌速度为1000 r/min,时间为2 h时得到的微胶囊的包埋率最高,粒径最小,分布最均匀。     

复凝聚法制备明胶/阿拉伯胶含油微胶囊工艺过程的研究

研究了复凝聚法制备含油微胶囊的工艺过程。以大豆油为囊芯材料,阿拉伯胶与明胶为璧材,研究了溶液pH值,反应温度,反应时间,壁材浓度,搅拌条件等对微胶囊产品质量的影响。发现搅拌速度对微胶囊的粒径大小和分布影响很大。最佳工艺条件为:明胶与阿拉伯胶质量比为1,浓度都为2%,pH值为4.0~4.5,搅拌速度为1500 r/min,反应温度为55℃,凝聚时间为15~20min,固化温度为10℃,固化时间60 min。     

溶剂挥发法制备聚砜包覆桐油自修复微胶囊

以聚砜为壁材,桐油为芯材,采用溶剂挥发法制备了聚砜（PSF）包覆桐油自修复微胶囊。考查了不同种类的分散剂、搅拌速度、芯壁比（芯材与壁材的质量比）等工艺参数对微胶囊性能的影响,通过扫描电子显微镜、光学显微镜和热重分析仪等对微胶囊的表观形貌、粒径、壁厚、包覆率和热稳定性能等进行表征。采用所合成的微胶囊制备了环氧树脂基防腐蚀涂层,并对其防腐蚀性能进行了评价。结果表明,30 ℃时,以明胶/聚乙烯醇复配体系作为分散剂,芯材与壁材质量比为1.3:1,搅拌速度为700 r/min时制备出的微胶囊表面光滑致密,粒径在130 μm左右,热稳定温度为350 ℃;盐雾实验结果表明,所制备的微胶囊自修复涂层具有良好的防腐蚀性能。     

聚砜包覆双环戊二烯微胶囊的制备

采用简单易控的溶剂挥发法成功制备了聚砜包覆双环戊二烯微胶囊,讨论了反应温度、分散剂、芯壁比及搅拌速度对微胶囊性能的影响,并通过扫描电子显微镜、光学显微镜和热重分析仪对微胶囊的表面结构、形貌和热性能进行了研究。结果表明,选择明胶溶液作为分散剂,反应温度为30 ℃时,可制备出粒径和壁厚可控的具有规则球形的微胶囊;随着芯材比例的增大,微胶囊壁厚减小;粒径随着搅拌速度的加快而减小。     

光甘草定脂质体制备及其质量评价

以光甘草定为原料,采用复凝聚法制备光甘草定脂质体,以包封率和粒度为指标,采用正交试验设计优化光甘草定脂质体的制备工艺;并对光甘草定脂质体的粒径分布、体外释药特性和稳定性进行了研究。结果表明:光甘草定脂质体制备的最佳条件为卵磷脂与胆固醇质量比4:1、超声波乳化时间40 min、光甘草定-丙二醇液质量浓度8 g/L,此条件下制得的脂质体粒径分布均匀,粒径为0.1~1.2 μm的比例为84.67%,包封率和粒度综合评分可高达78以上。光甘草定脂质体前120 min的体外释药性优于光甘草定粉末,3个月时光甘草定质量分数仍达38.5%,保留率为96.25%。复凝聚法制备光甘草定脂质体工艺简单,产品稳定性好。     

聚砜包覆环氧树脂微胶囊的制备

采用溶剂蒸发法制备了聚砜包覆双酚A型环氧树脂微胶囊,通过光学显微镜、激光粒度分布仪和微机差热天平对微胶囊的形貌、粒径分布及热性能进行了表征,讨论了分散剂种类及用量、搅拌速度、反应温度以及壁材与芯材投料质量比对微胶囊制备的影响。结果表明,反应温度过高时不能形成微胶囊;选择1.0 %（质量分数,下同）的聚乙烯醇分散剂、搅拌速度为750 r/min、反应温度为30 ℃、壁材与芯材投料质量比为2∶1时制得的微胶囊呈规则球形,产率较高,微胶囊分散较好,平均粒径在100 μm之内。     

溶剂挥发法制备氟乐灵微胶囊工艺条件

为了提高氟乐灵的光稳定性和药效,以聚羟基烷酸酯为壁材,采用溶剂挥发法制备氟乐灵微胶囊,并讨论芯壁比、分散剂质量分数、剪切时间和速度、油水相体积比对氟乐灵微胶囊成囊的影响。结果表明:当芯壁比为1∶5,油水相比为20∶100~30∶90,聚乙烯醇(PVA-1788)的质量分数为1%,剪切时间为3 min,剪切速度为8000 r/min,所得氟乐灵微胶囊呈球形,平均粒径在6.23~7.57μm,包封率为83.36%,载药量为14.62%。     

月桂酸微胶囊自修复涂层的制备及其防腐性能研究

主要针对碳钢基体,采用微胶囊包覆缓蚀剂技术以实现涂层的自修复性能。以脲醛树脂为壁材,月桂酸为芯材,采用两步法合成自修复微胶囊,并研究不同温度、pH、搅拌速度等工艺条件对微胶囊合成及结构的影响,优化合成工艺。将所合成的微胶囊添加在环氧树脂中,在碳钢表面制备涂层。结果表明:在合成温度60℃左右,pH 3～4,搅拌速度200 r/min时可以得到表面致密,粒径均匀的微胶囊;环氧涂层中加入微胶囊后,涂层的防护性能得到提高,具有明显的自修复性能。     

应用于自愈合涂料中微胶囊制备工艺的研究

以聚三聚氰胺-甲醛树脂（PMF）为囊壁,自千型成膜物质为囊芯,成功制备出粒径较小具有自愈合功能的微胶囊。试验考察了乳化剂种类、乳化剂用量和搅拌速率等因素对微胶囊粒径及其外貌的影响。并采用傅里叶红外光谱仪和偏光显微镜对微胶囊的结构、粒径和形貌进行表征。结果表明：比较合适的乳化剂是苯乙烯马来酸酐聚合物（SMA）,搅拌速率和乳化剂的添加量对微胶囊粒径有明显影响,并且制备的微胶囊加入涂料中有一定的自愈合能力。     

Preparative Purification of the Major Flavonoid Glabridin from Licorice Roots by Solid Phase Extraction and Preparative High Performance Liquid Chromatography

This study investigated a novel, simple, and economical method for the preparation and purification of glabridin from licorice roots. Glabridin was initially obtained from ethyl acetate extraction of licorice, followed by using solid phase extraction (SPE) and preparative high performance liquid chromatography (HPLC). The content of glabridin increased from 0.23% to 35.2% after SPE, and then a 16 mg product at a high purity of over 95% was obtained from 10 g licorice roots after purification by preparative HPLC. The purity was assessed by analytical HPLC, and the purified compound was characterized by LC-MS/MS and ¹H NMR.     

农药2,4-D微胶囊悬浮剂的研制

以脲醛树脂为壁材,采用原位聚合法制备2,4-D微胶囊悬浮剂。在固定合成脲醛树脂反应条件的基础上,通过改变成囊过程中囊心与囊壁比、固化剂种类及用量、搅拌速度、固化时间、固化温度、加酸时间、终点pH等的不同,进一步研究上述不同条件对微胶囊粒径大小、粒径分布范围、微胶囊包囊率的影响,从而筛选最优的成囊反应条件。实验结果显示该微胶囊能够满足实际需要。     

2％阿维菌素微胶囊水悬浮剂的制备

以甲苯二异氰酸酯和水溶性成膜单体乙二胺为壁材,采用界面聚合法制备阿维菌素微胶囊水悬浮剂.研究了分散剂、溶剂、芯壁比、乳化搅拌速度、聚合反应时间对微胶囊包囊率和包囊形态的影响.结果表明:该法芯材比可达到6-7.5,体系浓度可达到10％,而且制得微胶囊阿维菌素包囊率＞90％,粒径≤10μm,粒径分布均匀,贮存稳定性合格,可...     

薄荷油微胶囊的制备及其共混熔融纺丝

以密胺树脂为壁材、薄荷油为芯材制备薄荷油微胶囊并与聚丙烯(PP)进行熔融共混纺丝得到了芳香纤维。通过设计正交试验,获得微胶囊的最佳制备工艺条件为:芯壁质量比2∶3、壁材质量分数8%、乳化剂质量分数0.8%、缩聚时间2 h;所得的微胶囊平均粒径小(4.568μm)、热稳定性好、形貌规整且产率高(63.17%)。以PP为基体制备微胶囊质量分数20%的母粒,再与PP进行共混熔融纺丝,结果表明:当共混物中微胶囊的实际添加质量分数为2.5%时,共混物可纺性好,纤维的强度可达3.4 c N/dtex。在纺丝前后微胶囊的含油率变化不大,纤维中的含油量为14.05 mg/g。     

The electric response behavior and microencapsulation of the pigment phthalocyanine green G using interfacial polymerization

The polyamide microcapsules for the electrophoretic display have been prepared via interfacial polymerization. The core material of the microcapsules is electrophoretic fluid consisted of pigment phthalocyanine green G (CAS No. 1328-53-6) modified with octadecylamine, tetrachloroethylene, and polyoxyethylene octylphenol ether (OP-10). The wall of the polyamide is synthesized from paraphthaloyl chloride and diethylenetriamine. FT-IR indicated that octadecylamine was bonded to pigment phthalocyanine green G with the hydrogen bond. The effect of the amount of octadecylamine on the dispersibility of the pigment suspended in tetrachloroethylene was investigated. Compared to the unmodified pigment, the dispersibility of the modified pigment was improved by 66.7%. The modified pigment migrated to the positive electrode under the direct voltage and the electric response time was about 85 s in 20 V/mm. The average particle size of microcapsules decreased from 834.5 to 258.2 nm as the dosage of OP-10 increased, and the microcapsule yield reached maximum of 83.5% at the OP-10 concentration of 1.5 wt%. With the reduction of the core/wall weight ratio in the range from 1:6 to 1:14, the average particle size improved from 267.4 to 554.4 nm. However, the maximum of the microcapsule yield was 87.6% at the core/wall weight ratio of 1:10. The microcapsule yield reached a peak of 87.6% as the pH value was 12. The average particle size of the microcapsules that obtained at 25 °C was 327.4 nm, which was smaller than those prepared in other temperatures. The formed polyamide microcapsules had a regular spherical shape.     

Effect of drying method and wall material composition on the characteristics of camellia seed oil microcapsule powder

Camellia seed oil (CSO) is one of the richest sources of oleic acid (75–80%) and it is considered to provide beneficial health effects to humans. However, its susceptibility to oxidative degradation prevents its widespread use in the food industry. This study was aimed to improve the stability of camellia seed oil by microencapsulation. CSO was microencapsulated using whey protein concentrate (WPC) and maltodextrin (MD) or starch sodium octenylsuccinate (SSOS) as wall materials. The produced oil-in-water emulsion was subsequently dehydrated to produce microcapsule powder using spray and freeze drying techniques, respectively. Various characteristics of oil-in-water emulsion and final microcapsule powder including particle size distribution, encapsulation efficiency, morphology, rheological properties of reconstituted emulsions, in vitro digestion behavior and oxidative stability were determined to investigate the effect of wall material composition and drying method on these microcapsule powder characteristics. The spray-dried powder had significantly higher bulk density and smoother surface compared to freeze-dried powder while the freeze-dried CSO microcapsule powder with WPC/SSOS as wall material had the highest encapsulation efficiency and the lowest surface oil. The subsequent in vitro digestion test suggested the microencapsulated CSO could be successfully controlled-released in the simulated gastric (10.28–13.03%) and the subsequent intestinal fluid (72.89–89.61%). Oxidative stability of camellia seed oil was significantly improved by microencapsulation. The freeze dried CSO microcapsule powder in WPC/SSOS wall material exhibited highest encapsulation efficiency (95.17%) and best oxidative stability (peroxide value and p-anisidine values of 3.57 meq/kg oil and 3.01, respectively, during the 45 days storage at 25°C.     

Preparation and characterization of controlled-release microencapsulated acids for deep acidizing of carbonate reservoirs

Based on the deficiency of traditional acidification or acid pressure technology in the development of carbonate oil and gas resources, a microcapsule which wraps hydrochloric acid and can be released through temperature control was prepared by using microcapsule technology. The microcapsules were prepared with polyurethane prepolymer (PUA) and 1,6-hexadiol diacrylate (HDDA) polymer as wall material and hydrochloric acid as core material by two emulsification and photocatalysis methods. Its parcel rate is 61.9%. Fourier transform infrared spectroscopy characterization confirmed the successful photopolymerization of PUA prepolymer and HDDA in a strong acid environment. The microscopic morphology analysis of electron microscope showed that the microcapsule was regular and uniform spherical with smooth and dense surface. The particle size analysis showed that the microcapsules were mainly distributed between 40 and 300 μm, and the average particle size was 114.02 μm.The glass temperature of microcapsule wall material was 97°C by DSC method. The release rate of microcapsules was accelerated with the increase of release temperature. The cumulative release rate of acid solution of microcapsules for 3 h reached 28.4%, and the final release rate of microcapsules for 12 h reached 90.7% under 100°C. In addition, the release of microcapsules is less affected by the formation salinity. At 90°C, the maximum release rate of 7.5 g/L CaCL₂ was 49.1%, lower than that of 59.4% in pure water, showing the good salt resistance of the wall materials of microcapsules.     

成囊工艺对环氧树脂微胶囊形成状态影响

研究了分散、乳化条件及成囊工艺对以苯乙烯为壁材,采用原位聚合法制备苯乙烯微胶囊状态的影响。讨论了不同乳化剂及其配比,不同乳化分散时间、搅拌速度和固化温度对微胶囊的包覆率、粒径的大小及分布情况的影响,最终确定以阿拉伯树胶和DBS按1∶3的比例混合作为乳化剂,1500 r/min搅拌,分散乳化60 min,85℃固化3 h作为制备环氧树脂微胶囊的优化工艺条件。在此条件下得到平均粒径为15μm左右,粒度分布均匀的球形微胶囊,包覆率在80%以上。