将定向冰晶模板致孔技术引入到冰冻聚合过程当中，制备出具有取向性孔结构的聚乙二醇(PEG)多孔凝胶。在凝胶内表面的孔壁上吸附沉积一层致密的碳纳米管(CNTs)，得到一种特殊的PEG/CNTs复合多孔凝胶。通过对PEG凝胶的共聚改性，可以使得吸附的CNTs层更加均匀、致密，沉积的CNTs 的含量达到1.0%(wt)，而未经改性的PEG凝胶只能吸附约0.08%(wt)的CNTs。该复合凝胶在干燥状态下的导电率为1.5×10-1 S⋅m-1，比相同CNTs含量下，用常规原位聚合方法制备的CNTs复合凝胶的导电率(2.7×10-4 S⋅m-1)高出3个数量级；比用相同聚合方法制备的未经过改性的复合凝胶(2.9×10-4 S.m-1)也要高出3个数量级。该复合凝胶在充分溶胀状态下的导电率为5.2×10-2 S⋅m-1，比相同CNTs含量下，用常规原位聚合方法制备的CNTs复合凝胶的导电率高出2个数量级。%A unidirectional freezing technique was combined with cryopolymerization to prepare poly (ethylene glycol) (PEG) hydrogels with aligned porous structure. Freeze-dried samples were immersed in aqueous carbon nanotube (CNTs) dispersions. CNTs diffused into the pores of the hydrogel, and deposited onto the inner walls of the pores. Introducing a cationic moiety, (3-Acrylamidopropyl)trimethylammonium Chloride (AAPTAC) into the hydrogel by copolymerizing with PEGDA can enhance the deposition of CNTs, as electrostatic force together with van der Waals force improves the interreaction between CNTs and PEG. Therefore, the porous PEG hydrogels prepared are coated with a dense and compact CNTs layer. The obtained composite hydrogels possess good electrical conductivity, which is up to 1.5×10-1 S⋅m-1 in dry state. While the conductivity of the samples prepared by in situ polymerization is 3 magnitudes lower (2.7×10-4 S⋅m-1). The conductivity of the sample prepared using the same surface-deposition method but without a cationic moiety is as low as 2.9×10-4 S⋅m-1 because of less absorption of CNTs.
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