Acta Phys. -Chim. Sin. ›› 2007, Vol. 23 ›› Issue (10): 1572-1576.doi: 10.3866/PKU.WHXB20071015

• ARTICLE • Previous Articles     Next Articles

Effect of Hydrophobic Modification on Sustained-Release Properties of Alachlor/MCM-41

PENG Lin; YU Ning-Ya; TANG Qun-Li; QIU Hua-Yu; YIN Du-Lin; YIN Dong-Hong   

  1. Institute of Fine Catalysis and Synthesis, Hunan Normal University, Changsha 410081, P. R. China; College of Materials Science and Engineering, Hunan University, Changsha 410082, P. R. China; Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Teachers College, Hangzhou 310012, P. R. China
  • Received:2007-04-23 Revised:2007-06-14 Published:2007-10-01
  • Contact: YU Ning-Ya;YIN Dong-Hong (D.Yin); (N.Yu)

Abstract: The herbicide of alachlor was incorporated into the channels of MCM-41-type mesoporous silica (M41) by using an impregnation method. Surface hydrophobic modification of the assembly of alachlor-MCM-41 (Ach/M41), via a gas-solid reaction with 1,1,1,3,3,3-hexamethyldisilazane (HMDS), gave rise to an efficient sustained-release system (Ach/TMS-M41). The resulting Ach/TMS-M41 not only retained high alachlor loading capacity but also possessed prolonged alachlor release time. The characterization results of XRD, nitrogen adsorption/desorption, FT-IR, and TG analysis showed that the M41 retained its structural integrity during the alachlor-loading process and alachlor was dispersed completely in the channels of MCM-41 with a mass ratio of alachlor [m (alachlor)/m(alachlor-MCM-41)] as high as 0.381 g·g-1 (mass fraction 27.6%). The release properties of Ach/M41 and Ach/TMS-M41 in water were investigated. 62% and 38.1% of alachlor were released from Ach/M41 and Ach/TMS-M41 ofter 6 days, respectively, which indicated that hydrophobic modification of MCM-41 was conducive to sustained-release of alachlor. Furthermore, the framework of the mesoporous silica protected the encapsulated alachlor against ultraviolet light irradiation.

Key words: MCM-41, Hydrophobic modification, Alachlor, Herbicide, Sustained release