微胶囊红磷阻燃剂制备研究进展

微胶囊红磷的制备方法有界面聚合法、原位聚合法、溶胶-凝胶法、溶剂蒸发法、超临界法等。介绍了红磷的物化性质及毒性,叙述了红磷阻燃剂的缺陷、微胶囊红磷的特性和阻燃应用。综述了微胶囊红磷近十年来的制备研究进展情况。     

胺菊酯微胶囊的制备及性能表征

[目的]针对胺菊酯使用中存在的问题,制备性能优异的微胶囊。[方法]采用溶剂蒸发法,以乙基纤维素为壁材,二氯甲烷为溶剂,通过优化工艺参数制备胺菊酯微胶囊,并对微胶囊性能进行表征。[结果]以1.2%乙基纤维素,35%二氯甲烷,4%乳化剂R成功制备了大小均匀,形状规则,结构完整的胺菊酯微胶囊,平均粒径为56.8μm,包封率为50.7%,该微胶囊在乙腈水溶液中的释放机制为Non-Fickian扩散,与原药相比,微胶囊具有显著的缓释性能。[结论]溶剂蒸发法具有工艺简单、制备周期短、溶剂可回收、微胶囊外形好、缓释效果突出等特点,有利于胺菊酯的安全、有效使用。     

溶剂蒸发法制备高效氯氟氰菊酯微胶囊及其性能表征

针对高效氯氟氰菊酯使用过程中对人体皮肤的刺激性以及对水生生物的高毒性,以乙基纤维素为壁材,二氯甲烷为溶剂,通过设计L9（34）正交试验,采用溶剂蒸发法制备高效氯氟氰菊酯微胶囊,同时对微胶囊的理化性质和缓释特性进行表征。根据微胶囊平均粒径和未包封率的综合评分确定最佳制备工艺为：25%二氯甲烷,0.75%乙基纤维素,2%乳化剂,剪切8 min。扫描电子显微镜观察发现,所制微胶囊具有粒径大小均匀,表面光滑等特性;红外光谱图表明,高效氯氟氰菊酯被乙基纤维素包埋;释放特性曲线也表明微胶囊具有较好的缓释性能。该工艺操作简单,制备周期短,成囊性好,可为农药微胶囊的制备提供有效途径。     

微胶囊阻燃剂的研究进展

综述了微胶囊技术的发展史,概述了微胶囊阻燃剂相对于传统阻燃剂的优点,并介绍了微胶囊阻燃剂的5种制备方法:界面聚合法、原位聚合法、相分离法、乳液-溶剂蒸发法、物理机械法以及微胶囊的囊壁材料、囊芯材料的研究进展和微胶囊阻燃剂的应用概况。     

阻燃剂微胶囊化的研究进展

综述了微胶囊阻燃剂的发展和其相对于传统阻燃剂的优点及微胶囊阻燃剂囊壳材料的新进展,并对各种阻燃剂的微胶囊化及其最新应用进行了阐述。介绍了界面聚合法和原位聚合法的新工艺,并介绍了溶胶-凝胶、溶剂蒸发、超临界等3种新的微胶囊阻燃剂制备方法。     

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。     

W／O／W复乳溶剂蒸发法制备微胶囊的影响因素及研究新进展

重点综述了W/O/W复乳溶剂蒸发法制备微胶囊的过程及影响因素,并结合SPG膜乳化法阐述了其最新研究进展.     

溶剂蒸发法制备甲维盐微胶囊及其性能表征

[目的]针对甲维盐传统加工剂型在实际应用过程中易光解、持效期短等缺点,采用溶剂蒸发法制备了甲维盐微胶囊。[方法]通过单因素和正交试验L9(34)优选了工艺参数,并对微胶囊理化特性及释放性能进行表征。[结果]溶剂用量、壁材用量和剪切速率显著影响微胶囊的平均粒径;壁材用量和乳化剂用量显著影响微胶囊的包封率。正交试验获得的优化配方为1%甲维盐,30%二氯甲烷,0.8%乙基纤维素,4%吐温-20,剪切速率22 000 r/min。所获得的甲维盐微胶囊粒径适中(16.83μm),包封率为47.69%,具有良好的缓释性能。[结论]该研究获得了性能较好的甲维盐微胶囊产品,对使用溶剂蒸发法制备其他农药微胶囊也有一定的借鉴作用。     

一种水溶性囊芯微胶囊的制备方法

以水为囊芯,以聚对苯二甲酸二乙酯（PET）为囊壁,采用乳液-溶剂蒸发法合成一种水溶性囊芯的微胶囊,微胶囊表面光滑,粒径分布窄,平均粒径约100μm。采用扫描电子显微镜（SEM）和光学显微镜（OM）表征微胶囊的表面形貌特征,粒径及其分布。实验结果表明,乳化剂浓度和芯／壁比例等对PET微胶囊大小和粒径分布有较大影响。     

CS／PLLA／TPP纳米微胶囊的制备及体外释放

主要考察负载雷帕霉素（Rapaymcin,RAPA）的壳聚糖（Chitosan,CS）微球在加入左旋聚乳酸（L—polylactic acid,PLLA）时的载药量,包封率及在不同溶剂中的缓释性能。采用三聚磷酸钠（Sodium tripolyphosphate,TPP）作为离子交联剂,应用离子凝聚法制备CS／PLLA／TPP纳米微胶囊,用透射电镜和粒径分析仪进行了表征。结果表明：离子凝胶法可以得到粒径约300—400nm均匀分散的壳聚糖纳米微胶囊;微胶囊包封率可达84．25％,微胶囊载药量可达30．22％,雷帕霉素在不同溶剂中的缓释性能有很大不同。     

Preparation of ethyl cellulose microcapsules containing perphenazine and polymeric perphenazine based on acryloyl chloride for physical and chemical studies of drug release control

The preparation of microcapsules containing perphenazine by solvent evaporation using ethyl cellulose is described. The microparticles are formed after solvent evaporation and polymer precipitation. The drug was dissolved in a polymer solution and emulsified into an aqueous phase to form microcapsules. To study the effects on particle size, encapsulation efficiency and morphology, three different molecular weights of ethyl cellulose (M_w=47000, 71000 and 99000) were used. Covalent bonding of drugs to polymers via hydrolytically or enzymatically cleavable covalent bond was achieved for sustained drug delivery. The release rate of perphenazine from these systems was investigated. © 1998 Society of Chemical Industry     

超临界乳液萃取法制备载槲皮素微胶囊

采用超临界乳液萃取法(SFEE)制得载槲皮素微胶囊,系统考察了制备过程中萃取温度、压力、CO2流速、配制乳液参数对溶剂残留与微胶囊粒径的影响。采用顶空气相色谱法、场发射扫描电镜、Zeta电位、FTIR对溶剂残留与微胶囊进行表征。结果表明:在313 K、9 MPa、CO2流速为0.4 L/min的条件下,处理40 min,溶剂残留可低至59 mg/L。壁材质量浓度从10 g/L增加至100 g/L时,微胶囊粒径由0.9μm升至3.7μm。与溶剂蒸发法相比,SFEE法可在短时间内有效去除有机溶剂,所制备的微胶囊球形度高,界面清晰,在水中稳定性好。     

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。     

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。     

溶剂蒸发法制备磁性微胶囊及其相关性能

将共沉淀法所得纳米OA-Fe3O4(油酸改性Fe3O4)分散于不同介质中形成磁流体作为芯材,以PMMA(聚甲基丙烯酸甲酯)作为壁材,采用溶剂蒸发法制备磁性微胶囊。对不同芯材及乳化剂进行筛选;考察乳化剂用量、m(芯材)∶m(壁材)及乳化转速对微胶囊制备的影响。通过XRD、FTIR、TEM、SEM、光学显微镜、VSM(振动样品磁强计)对纳米OA-Fe3O4和磁性微胶囊的有效成分、形貌、热性能、磁性能进行分析表征。结果表明,共沉淀法制备的纳米颗粒有效成分为Fe3O4,且可形成稳定磁流体。OA-Fe3O4粒径在3～15 nm,比饱和磁化强度为43.3 emu/g,具有顺磁性。以分散在n-C16H34的OA-Fe3O4磁流体为芯材,w〔SDS(十二烷基硫酸钠)〕=2%的水溶液为乳化剂,m(芯材)∶m(壁材)=5∶1,乳化转速800 r/min条件下可制得外形规整,壁厚1～2μm,且粒径集中于(10±2)μm的磁性微胶囊。该胶囊比饱和磁化强度为36.9 emu/g,具有良好的磁响应性。     

潜伏性2MMZ-PS微胶囊固化剂的制备与表征

以2-甲基咪唑(2MMZ)为芯材,聚苯乙烯(PS)为壁材,采用溶剂挥发技术,制备了一种新型潜伏性2MMZ-PS微胶囊固化剂。通过红外光谱仪(FT-IR)、热重分析仪(TGA)、扫描电子显微镜(SEM)、粒度分析仪和差热扫描量热仪(DSC)对微胶囊固化剂的化学结构、芯材含量、表面形貌、粒径分布及固化性能等进行了表征。所制备的微胶囊固化剂表面光滑,粒径分布较窄,平均粒径约为10.18 μm,芯材2MMZ含量为40.36%。由微胶囊固化剂与环氧树脂E-51制备的单组分胶黏剂,具有优良的固化特性和潜伏性能,可在相似文献   

Latent curing agent DDM-PMMA microcapsule for epoxy resin

A microcapsule-type latent curing agent is prepared by solvent evaporation method with diaminodiphenylmethane (DDM) as the core material and PMMA as the wall material. The chemical structure, surface morphology, core content, and curing characteristics of as-prepared microcapsule-type curing agent are characterized by FTIR, SEM, TGA, and DSC. The results show that the obtained microcapsules have smooth surface and the core content is about 20 wt %. The one-component adhesive consisting of DDM-PMMA microcapsule and epoxy resin can be cured within 30 min at 130 °C, and the room temperature latent period is more than 30 days. In addition, the internal reasons influencing the core content of microcapsules are analyzed by comparing and analyzing the structural compatibility of three kinds of wall material PMMA, PS, and polyetherimide with DDM. The results show that the core content is affected by the compatibility of wall material and core material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47757.     

Microencapsulation of imidazole curing agent by solvent evaporation method using W/O/W emulsion

The epoxy–imidazole resin system is used to form the anisotropic conducting film. The latent character of the system is very significant. In this study, imidazole (Im) or 2‐methylimidazole (2MI) was encapsulated for the latent curing system to use in the reaction of epoxy resin. Polycaprolactone was used as a wall material, and the solvent evaporation method was used to form the microcapsule using W/O/W emulsion. The shelf life of the microcapsules was studied for the epoxy resin, and the curing behavior of the microcapsules for epoxy resin was examined using a differential scanning calorimeter. The curing times at 150 and 180°C were estimated using an indentation method. The microcapsules of Im or 2MI exhibited a long shelf life for epoxy resin. When comparing the results of the previous methods with the results of this study using the W/O/W emulsion, finer microcapsules were formed and the microcapsule has longer shelf life. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Structural control of core/shell polystyrene microcapsule‐immobilized microbial cells and their application to polymeric microbioreactors

Polystyrene microcapsules possessing a large single core and highly microporous wall were prepared as immobilization supports for microbial cells by a new method based on phase separation of polystyrene within a mixed organic solvent system in an oil‐in‐water (o/w) emulsion. The structures of core and micropore were controlled by changing the concentration of isooctane in the organic phase and the temperature of solvent evaporation. The immobilization of baker's yeast into the polystyrene microcapsules was carried out by entrapping the yeast into calcium alginate beads before encapsulating in the microcapsules and followed by removing the beads with HCl solution. The morphology of the microcapsules was observed by means of SEM, and the activity of the immobilized yeast was evaluated by using the microcapsules in ethanol fermentation. It was found that the formation of the core and wall pore was remarkably influenced by the isooctane concentration, and the diameter of the core was affected by the temperature of solvent evaporation. The yeast was successfully immobilized into the polystyrene microcapsules at a high density and a high catalyst activity by the proposed immobilization method. Furthermore, the polystyrene microcapsules exhibited a high operational stability in the repeated batchwise fermentation test. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1966–1975, 2003