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1.
《应用化工》2022,(4):1059-1062
以斯盘-80、OP-10为乳化剂,油酸乙酯为油相,通过表面活性剂复配方法制备了新型癸氧喹酯乳液制剂,对制剂稳定性、粒径进行了表征,并建立了新型癸氧喹酯乳液含量测定HPLC法。结果表明,制备的癸氧喹酯乳液制剂分散均匀,平均粒径0.548μm,粒径分布在0.105~1.997μm。采用高效液相反相色谱法,色谱柱为Sepax HP-C_(18)(4.6 mm×250 mm,5μm),流动相:以乙腈∶0.2%冰醋酸(85∶15)为流动相,流速0.8mL/min,检测波长265 nm,进样体积20μL;柱温为30℃,测得3批癸氧喹酯乳剂中癸氧喹酯的含量分别为标示量的100.07%,100.33%,98.59%,在2.48~496.00μg/mL范围内线性关系良好(R2=0.999 2),平均加样回收率分别为99.38%,100.22%,99.79%,RSD分别为1.08%,0.78%,1.04%。  相似文献   

2.
溶剂蒸发法制备磁性微胶囊及其相关性能   总被引:2,自引:0,他引:2  
陈红苗  罗艳 《精细化工》2012,29(9):844-849
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。  相似文献   

3.
超细BTF粒子的制备   总被引:3,自引:0,他引:3  
分别采用溶剂/非溶剂结晶法和机械研磨法探索了超细BTF粒子的制备,目前采用溶剂/非溶剂结晶法还难以使BTF粒子粒径细化至微米级,采用机械研磨法获得了平均粒径0.774μm,比表面积19.95m^2/g的亚微米级超细BTF粒子。  相似文献   

4.
研究以明胶和阿拉伯胶为壁材,采用复凝聚法研究了光甘草定微胶囊的制备工艺,探讨了芯壁质量比、增溶剂使用量、乳液均质时间和搅拌速度的影响,通过正交试验确定最佳工艺条件为芯壁比为2∶1,增溶剂为0.5%,均质时间为10 min,搅拌速度为750 r/min。通过本工艺制备得到的光甘草定微胶囊包裹率可达40%,粒径分布均匀(平均粒径3.91μm),将其喷雾干燥后得到光甘草定微胶囊粉末为淡黄色,无刺激气味,可溶于丙二醇等有机溶剂。包裹后的光甘草定微胶囊,减淡了原有的棕黑颜色和刺鼻气味,可很好地用作化妆品美白添加剂。  相似文献   

5.
采用顶空气相色谱法,建立了同时测定哌啶甲酸盐中四种残留溶剂的方法,并对方法进行了系统的方法学验证。方法采用6%氰丙基苯基-94%二甲基聚硅氧烷为固定液的毛细管柱为色谱柱进行分离、氢火焰离子化检测器检测、外标法定量的分析方案,实现了乙醇、丙酮、乙酸乙酯和1,4-二氧六环4种溶剂残留的同时分离与测定。4种溶剂在各自的线性范围内线性关系良好,线性相关系数(r)均大于0.998,定量限分别为乙醇0.409μg/m L、丙酮0.100μg/m L、乙酸乙酯0.100μg/m L和1,4-二氧六环0.039μg/m L。实际样品分析结果表明,本方法简单、快速、分离效果好,可用于哌啶甲酸盐中4种残留溶剂的检测。  相似文献   

6.
以乙基纤维素为壁材、二氯甲烷为溶剂,采用溶剂蒸发法制备了高效氯氟氰菊酯微胶囊。通过单因素实验考察了溶剂质量分数、壁材质量分数、乳化剂质量分数和剪切时间对微胶囊平均粒径的影响,通过以微胶囊平均粒径和未包封率作为评价指标的正交实验L9(34)优选了最佳工艺,并通过SEM、FTIR和HPLC对微胶囊的外观形貌、包覆效果和释放性能进行了表征。结果表明:随着溶剂质量分数增大,微胶囊平均粒径先减小后增大,w(溶剂)=25%时,平均粒径最小。随着壁材质量分数增大,微胶囊平均粒径增大。随着乳化剂质量分数增大,微胶囊平均粒径逐渐减小。固定剪切速率,微胶囊平均粒径随着剪切时间增加而减小。以w(二氯甲烷)=25%、w(乙基纤维素)=0.75%、w(乳化剂)[m(Tween80)∶m(Span20)=5∶1]=2%、剪切时间为8 min的工艺条件下得到的微胶囊外观光滑,形态规则,粒径较小(约19.2μm)且均匀,包封率高达82.8%,且具有较好的缓释性能。  相似文献   

7.
以可生物降解的聚丁二酸丁二醇酯(PHs)为基材,用乳液蒸发法制备不同负载量的荧光颜料/PSB微胶囊。用粒度仪、扫描电镜、透射电镜等表征微胶囊的粒径和形貌,用测色计和荧光光谱仪测定微胶囊色度及荧光性能。结果表明,在颜料与PBS质量比例为1:1、2:1、3:1时,所得微胶囊M1、M2、M3平均粒径分别为12.3μm、10.5μm、12.5μm,颗粒外形规整,分散性较好。相比于纯颜料,颜料微胶囊M1、M2、M3在塑料中分散后,艳度(△C)均增加,荧光性能得到保持。  相似文献   

8.
为开发出辛酰溴苯腈新剂型,提高其防治效果,降低施用量,本研究以聚羟基丁酸酯(PHB)为壁材,辛酰溴苯腈为芯材,三氯甲烷为溶剂,聚乙烯醇(PVA)为乳化剂,采用溶剂蒸发法制备微胶囊,通过单因素及L9(34)正交设计试验确定其最佳制备工艺,测定其载药量、包封率、粒径及分布、缓释性能和除草活性。试验结果表明,辛酰溴苯腈微胶囊最佳制备工艺条件为芯壁材质量比为1∶5,油水体积比为1∶5,PVA质量分数为2%,剪切速率为12 000 r/min,其制备的微胶囊中位粒径D50值为24.82μm,分散均匀,载药量为18.38%,包封率达91.90%。该微胶囊释放性能良好,148 h累积释放率达83%;辛酰溴苯腈微胶囊有效成分360 g/hm2药后7 d对藜的株防效为95.83%,与商用乳油制剂有效成分450 g/hm2的株防效无显著差异。制备的辛酰溴苯腈微胶囊能有效减少辛酰溴苯腈使用量。  相似文献   

9.
低温可逆热敏示温微胶囊的粒径控制及结构   总被引:2,自引:0,他引:2  
采用界面聚合法制备了以CoCl2为芯材、聚乙烯醇为壁材的可逆热敏示温微胶囊,系统研究了乳化剂用量、内水相与油相用量比、搅拌速度、内乳液加入方式对微胶囊粒径的影响,并对微胶囊的结构和形貌进行了表征. 结果表明,当Span-80/Tween-80含量为5%(w)、水油体积比为0.2、转速为1200 r/min、内乳液采用逐步滴加方式加入外水相中时,制备的微胶囊粒径均一,平均粒径为12 mm,分散性好.  相似文献   

10.
[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。  相似文献   

11.
Methoxy poly(ethylene glycol)-b-poly(L-lactide) (MPEG-PLLA) diblock copolymer was synthesized via ring-opening polymerization, and MPEG-PLLA microparticles were then prepared using an aerosol solvent extraction system (ASES) technique with compressed carbon dioxide as antisolvent. The MPEG-PLLA microparticles were prepared at temperatures ranging from 25 °C to 55 °C and at pressures from 85 bar to 150 bar. The concentration of MPEG-PLLA copolymer, solution flow rate, and CO2 flow rate were adjusted to be 0.5–3.0% (w/v), 0.3–1.0 mL/min, and 19 g/min, respectively. Relatively small spherical microparticles were prepared in the subcritical region at 25 °C, while agglomerated particles were obtained at temperatures above the critical point. The mean particle sizes of the MPEGPLLA microparticles prepared by the ASES varied from 9.53 μm to 46.9 μm depending upon the operating conditions.  相似文献   

12.
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。  相似文献   

13.
Microencapsulation of pesticides is a promising technique for avoiding high initial doses and multiple applications of the chemicals to agricultural land which cause environmental pollution. It is because the formulation is possible to improve the stability of the chemicals against environmental degradation and control the release rate. In the present study, polymeric microcapsules prepared by the solvent evaporation method via water-in-oil-in-water (W/O/W) emulsion were used as immobilization supports of acetamiprid, a water-soluble pesticide. The pesticide was loaded in the microcapsules by impregnating the polymeric supports with acetamiprid dissolved in an organic solvent. Increased volume ratio (ϕ) of inner aqueous phase to oil phase in the emulsion system contributed to more pores in the microcapsules and increase in the content of acetamiprid in the polymeric supports. Release rate of acetamiprid from the microcapsules could be controlled by changing ϕ.  相似文献   

14.
纪红兵  方岩雄 《精细化工》2012,29(7):678-682
采用单因素实验对喷雾干燥法制备β-环糊精/香兰素微胶囊进行研究,以微胶囊的包埋率和装载量为指标优选出最佳的工艺条件为:ρ(β-环糊精)=79.5 g/L,n(香兰素)∶n(β-环糊精)=0.8∶1.0,V(无水乙醇)∶V(水)=1∶10,进风温度130℃,进风速度3.9 m/s,物料流量15 mL/min,得到产品包埋率和装载量分别是69.1%和10.6%。红外光谱结果表明,香兰素与β-环糊精存在分子间相互作用。热重-差热分析结果表明,微胶囊的形成提高了香兰素的热稳定性。粒度分析显示,在50 d存放期间,β-环糊精的平均粒径变化值为0.14~1.2μm,而产品的平均粒径变化值为0.011~0.22μm,后者比前者小,进一步印证了香兰素与β-环糊精形成了超分子微胶囊。  相似文献   

15.
Supercritical fluid extraction is a viable alternative process for extracting oil from olive husk, a residue obtained in the olive oil production. We analyzed the effects of pressure (P) (100–300 bar), temperature (T) (40–60°C), solvent flow (1–1.5 L/min), and particle size (D) (0.30–0.55 mm) on extraction yield, and three oil-quality parameters: acidity (OA), PV, and phosphorus content (PC). A response surface methodology based on the statistical analysis of the experimental data permitted us to obtain mathematical expressions relating the operational variables and parameters studied. At the best extraction condition of the experimental range analyzed (P=300 bar, T=60°C, D=0.30 mm, and solvent flow=1.25 L/min at standard conditions), the oil yield was 80% (w/w) with respect to hexane extraction, whereas the quality parameters OA, PV, and PC were 14% (w/w), 8 meq/kg, and 2.3·10−3% (w/w), respectively. These results were compared to those obtained by hexane Soxhlet extraction. The quality of the supercritical extract was superior, requiring only simple refining. This advantage may result in improved economics of the supercritical process in relation to the conventional extraction with hexane.  相似文献   

16.
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。  相似文献   

17.
The gas anti-solvent (GAS) process was employed to extract andrographolide, which is the active ingredient found in Andrographis Paniculatanees, using carbon dioxide as an anti-solvent. The effects of temperature, flow rate and solvent type on the extraction recovery, particle size and morphology were investigated in this study. The experiments were conducted at the temperature ranging from 25–45 °C, carbon dioxide flow rate of 1–15 mL/min, and various types of organic solvents (methanol, ethanol, acetone and N,N-dimethylformamide). The extracted product was analyzed using high performance liquid chromatography (HPLC). The highest extraction yield was found to be 1.24 g andrographolide per 100 g of A. paniculata when using acetone as a solvent, carbon dioxide flow rate of 5 mL/min and the temperature of 35 °C. It was also found that no significant change in size or morphology of the precipitates was observed when changing temperature, carbon dioxide flow rate and solvents.  相似文献   

18.
Cu-Zn based catalysts for the direct synthesis of dimethyl ether were prepared by the co-precipitation method, and the feeding rate of ammonium carbonate used as the precipitant was controlled in order to change the particle size of the active materials. SEM and XRD confirmed that the catalyst particles that were prepared have a small size when the precipitant is rapidly fed into the precursor solution. The crystal growth of the Cu-Zn based catalyst could be controlled by changing the feeding rate of the precipitant in the precipitation method, and the physical properties of the Cu-Zn based catalyst were improved by controlling the crystal growth rate in order to enhance the catalytic activity. The feeding rate of the precipitant solution was controlled in range of 1.5–10.0 ml/min in this study. When the feeding rate of precipitant was adjusted from 1.5 ml/min to 10.0 ml/min, the particle size of Cu-Zn catalysts decreased from 28 nm to 10 nm with increasing feeding rates of precipitant solution and their surface area increased from 28 m2/g to 80 m2/g. The conversion of CO obtained in the catalytic activity tests also increased from 13% to 60%. A high conversion of CO was obtained over the Cu-Zn based catalysts prepared by changing the feeding rate of the precipitate.  相似文献   

19.
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...  相似文献   

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