The effects of different synthetic conditions on the porous properties of carbon cryogel microspheres
The effects of different synthetic conditions on the porous properties of carbon cryogel microspheres
复制标题
DOI：
10.1016/j.carbon.2004.12.016
复制
发表时间：
2005-05
期刊：
影响因子：
10.9
通讯作者：
Takuji Yamamoto;A. Endo;T. Ohmori;M. Nakaiwa
中科院分区：
文献类型：
--
作者：
Takuji Yamamoto;A. Endo;T. Ohmori;M. Nakaiwa
以间苯二酚-甲醛（RF）水溶液为原料，以SPAN 80为乳化剂，通过反相乳液聚合法合成了碳晶凝胶微球（CC微球）。研究了反相乳液聚合的条件，特别是SPAN 80与环己烷的体积比、乳化温度、Tgel和乳化后的保持时间。结果表明，反相乳液聚合过程中，RF水溶液被含SPAN 80的环己烷脱水，脱水程度可通过改变Tgel而改变。在Tg低于313 K的情况下，这种脱水导致在CC微球上形成超微孔表面。相反，高于323 K的Tg导致脱水的抑制，这反过来又导致介孔CC微球。在Tgel= 333 K下合成的微球的介孔性可以通过改变RF水溶液制备中使用的碱性催化剂的量来改变。
Carbon cryogel microspheres (CC microspheres) are synthesized through the inverse emulsion polymerization of a resorcinol-formaldehyde (RF) aqueous solution in cyclohexane using SPAN80 as an emulsifier. The conditions of the inverse emulsion polymerization, specifically the volume ratio of SPAN80 to cyclohexane, the temperature of the emulsification, Tgel, and the holding time after the emulsification, are examined. It is revealed that the RF aqueous solution is dehydrated by cyclohexane containing SPAN80 during the inverse emulsion polymerization, and that the degree of dehydration can be changed by varying Tgel. In the case of a Tgellower than 313K, this dehydration leads to the formation of ultramicroporous surfaces on the CC microspheres. Conversely, a Tgelhigher than 323K results in the suppression of dehydration, which in turn leads to mesoporous CC microspheres. The mesoporosity of the microspheres synthesized at Tgel=333K can be changed by varying the amount of basic catalyst used in the preparation of the RF aqueous solution.