Hydrophobicity functional group stepwise

Increasing Hydrophobicity by Stepwise Replacement of the Functional Group with a More Hydrophobic Residue... 

In addition to simplicity of the proposed one-step procedure, it allows for synthesis of ordered mesoporous materials of higher hydrophobic properties than parent materials. In fact, a high coverage of the grafted alkylsilyl groups stabilizes MCM-41 with respect to various environmental factors, as it was mentioned elsewhere [4]. Also, this study shows that the proposed previously procedure for stepwise modification of uncalcined MCM-41 samples [16] requires further studies in order to carry out a selective functionalization of the external surface and mesopore walls of these materials... 

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