Preparation of glycerol dimethacrylate-based polymer monolith with unusual porous properties achieved via viscoelastic phase separation induced by monodisperse ultra high molecular weight poly(styrene) as a porogen
Preparation of glycerol dimethacrylate-based polymer monolith with unusual porous properties achieved via viscoelastic phase separation induced by monodisperse ultra high molecular weight poly(styrene) as a porogen
复制标题
DOI：
10.1016/j.chroma.2006.01.133
复制
发表时间：
2006-06-30
影响因子：
4.1
通讯作者：
Ishizuka, Norio
中科院分区：
文献类型：
--
作者：
Aoki, Hiroshi;Kubo, Takuya;Ishizuka, Norio
采用二甲基丙烯酸甘油酯（GDMA）作为单体，单分散标准聚苯乙烯（PS）氯苯溶液作为致孔剂，对聚合物基整体式毛细管的制备进行了研究。使用分子量（以下定义为 Mw）从 50,000 到 3,840,000 的标准 PS 在试管中原位制备聚 GDMA 整体材料，并将其形态与用 GDMA 不良致孔溶剂原位制备的聚 GDMA 整体材料的形态进行比较。根据扫描电子显微照片（SEM）观察，以甲苯为不良致孔溶剂原位制备的聚GDMA整体结构呈现出典型的团聚球状结构，而用聚合物（PS）致孔溶液原位制备的聚GDMA整体结构随着所用标准PS分子量的增加从团聚球状形态转变为三维（313）连续骨架结构。随着这种形态转变或变化，在用超高Mw标准PS致孔溶液原位制备的聚GDMA整体材料的情况下，孔径分布呈现出尖锐的双峰分布，一个峰分别位于中孔范围（2-50 nm）中4 nm左右，另一个峰分别位于大孔范围（> 50 nm）中1-2 μ m左右。分别用甲苯、低分子量（50,000、600,000）PS氯苯溶液和上述超高分子量PS氯苯溶液作为致孔剂原位制备聚GDMA毛细管，并通过R-HPLC以苯和正烷基苯基酮作为溶质在甲醇水溶液（MeOH/H2O = 50/50-80/20， v/v）。采用超高Mw标准PS聚合物致孔溶液原位制备的毛细管的渗透性比采用低Mw标准PS聚合物致孔溶液或以甲苯作为致孔剂原位制备的毛细管的渗透性大得多。另一方面，用超高分子量 PS 溶液原位制备的毛细管的柱效优于后者的毛细管。这些观察结果表明，超高分子量标准 PS 聚合物致孔溶液由于其粘弹性，应动态延迟聚合混合物的相分离，并应有助于更好地创建三维连续骨架整体结构，以提供高分离效率。 (c) 2006 Elsevier B.V. 保留所有权利。
The preparation of polymer-based monolith capillary was examined by the use of glycerol dimethacrylate (GDMA) as monomer and monodisperse standard polystyrene (PS) solution in chlorobenzene as porogen. Poly-GDMA monoliths were prepared in situ in test tubes with standard PS having the variety of molecular weight (defined as Mw hereafter) from 50,000 to 3,840,000, and their morphology was compared to that of poly-GDMA monolith prepared in situ with a poor porogenic solvent of GDMA. According to scanning electron micrograph (SEM) observation, the structure of poly-GDMA monolith prepared in situ with toluene as a poor porogenic solvent showed a typical agglomerated globular structure, whereas the morphology of poly-GDMA monolith prepared in situ with the polymer (PS) porogenic solution was transformed from the aggregated globule form to three dimensionally (313) continuous skeletal structure with the increase of Mw of standard PS utilized. Along with this morphological transformation or change, in the case of poly-GDMA monolith prepared in situ with ultra high Mw standard PS porogenic solution, the pore size distribution showed a sharp bimodal distribution, with one peak being located around 4 nm in the mesopore range (2-50 nm) and the other peak located around 1-2 mu m in the macropore range (> 50 nm), respectively. The poly-GDMA capillaries were prepared in situ with toluene, low Mw (50,000, 600,000) PS solution in chlorobenzene and the above mentioned ultra high Mw PS solution in chlorobenzene as a porogen, respectively, and measured by R-HPLC with benzene and n-alkyl phenyl ketone as solutes for the evaluation in aqueous methanol (MeOH/H2O = 50/50-80/20, v/v). The permeability of capillaries prepared in situ with ultra high Mw standard PS polymer porogenic solution was much larger, compared to those of the capillaries prepared in situ with low Mw standard PS polymer porogenic solution or with toluene as porogen. On the other hand, the column efficiency was better in the case of the capillary prepared in situ with the ultra high Mw PS solution than in the latter capillaries. Those observations indicated that the ultra high Mw standard PS polymer porogenic solution should delay dynamically the phase separation of polymerizing mixture because of its visco-elasticity and should contribute to the creation of three dimensionally continuous skeletal monolith structure better to afford high separation efficiency. (c) 2006 Elsevier B.V. All rights reserved.