POLY(ALKYLCYANOACRYLATE) NANOCAPSULES - PHYSICOCHEMICAL CHARACTERIZATION AND MECHANISM OF FORMATION
POLY(ALKYLCYANOACRYLATE) NANOCAPSULES - PHYSICOCHEMICAL CHARACTERIZATION AND MECHANISM OF FORMATION
复制标题
DOI：
10.1023/a:1018938026615
复制
发表时间：
1994-06-01
影响因子：
3.7
通讯作者：
LENAERTS, V
中科院分区：
文献类型：
--
作者：
CHOUINARD, F;BUCZKOWSKI, S;LENAERTS, V
聚（氰基丙烯酸异丁酯）和聚（氰基丙烯酸异己酯）的纳米胶囊通过将单体加入有机相中，随后将有机相与含有泊洛沙姆188、238或407的水相混合来制备。凝胶渗透色谱表明，在文献报道相反，聚合反应发生在有机相和纳米胶囊得到的聚合物的界面沉淀没有任何显着的分子量的变化。在引入单体之前向有机相中添加SO2允许制备具有较低分子量的纳米胶囊。以类似的方式制备纳米球，尽管使用在水相中完全混溶的有机相，使得获得固体球。密度梯度离心表明，纳米胶囊具有纳米球和以相同方式制备的乳液之间的密度中间体，而不添加单体的有机相。此外，用于制备纳米胶囊的方法具有高产率，因为通过该方法没有获得油滴或纳米球。发现纳米胶囊和球的Zeta电位与聚合物的分子量相关：对于低分子量纳米胶囊（MW约为1000）获得高达约-42 mV的值，而对于乳液和高分子量纳米胶囊（MW约为100 000）获得约-10 mV的值。纳米胶囊的表面电荷和聚合物壁的分子量决定了泊洛沙姆的吸附能力。此外，用最疏水的泊洛沙姆测量最高的吸附。这些意见同意与以前的工作进行疏水表面。
Nanocapsules of poly(isobutylcyanoacrylate) and poly(isohexylcyanoacrylate) were prepared by addition of the monomer to an organic phase and subsequent mixing of the organic phase to an aqueous phase containing poloxamer 188, 238 or 407. Gel permeation chromatography indicated that in contrast to literature reports, polymerization occurred in the organic phase and nanocapsules were obtained by interfacial precipitation of the polymer without any significant change of the molecular weight. Addition of SO, to the organic phase before the introduction of the monomer allowed preparation of nanocapsules with a lower molecular weight. Nanospheres were prepared in a similar way albeit using an organic phase that was completely miscible within the aqueous phase so that solid spheres were obtained. Density gradient centrifugation revealed that nanocapsules had a density intermediate between nanospheres and an emulsion prepared in the same way without addition of monomer to the organic phase. Further, the process used to prepare nanocapsules had a high yield since no oil droplets or nanospheres were obtained by this process. Zeta potential of the nanocapsules and spheres was found to be related to the molecular weight of the polymer: values as high as approximate to -42 mV were obtained for low molecular weight nanocapsules (MW approximate to 1000) compared to approximate to - 10mV for the emulsion and the high molecular weight nanocapsules (MW approximate to 100 000). Surface charge of the nanocapsules and molecular weight of their polymeric wall conditioned the adsorption capacity of poloxamers. Moreover, the highest adsorption was measured with the most hydrophobic poloxamer. These observations agree with previous work conducted on hydrophobic surfaces.