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다공성 SiO2-B2O3 막을 졸겔법에 의해서 Si(OC2H5)4-(CH3O)3B-H2O-C2H5OH 계로부터 제조하고 막의 특성을 XRD, IR, BET, TG-DTA, SEM, TEM을 사용하여 조사하였다. 괴상의 다공성 SiO2-B2O3 막 제조를 위한 Si(OC2H5)4 : (CH3O)3B : H2O : C2H5OH의 최적 몰비는 1 : 0.11 : 5.385 : 5.385 이었다. Si(OH4)와 B(OH)3는 400 ℃ 이하에서 생성되고 SiO2-B2O3는 500 ℃ 이상에서 생성되었다. 25 ℃∼800 ℃ 온도범위에서 얻어진 건조 겔체는 평균 기공직경이 0.0034 μm∼0.0052 μm이고 표면적은 244.478 m2/g∼648.138 m2/g이었으며, 입자의 크기는 7 nm∼35 nm인 무정형의 다공체이었다.


A porous borosilicate membrane was prepared from Si(OC2H5)4- (CH3O)3B-H2O-C2H5OH system by sol-gel method. In order to investigate the characteristics of this membrane, the analytical methods such as X-ray diffractometer, IR spectrophotometer, BET, TG-DTA, SEM and TEM have been utilized. For porous borosilicate membrane, the optimum mole ratio of Si(OC2H5)4 : (CH3O)3B : H2O : C2H5OH was 1 : 0.11 : 5.385 : 5.385. Most of borons in the gels dried at room temperature were considered to be of boric acid forms, since they were hydrogen bonded to the silica network. In the 100 ℃∼500 ℃ range, however, some of the boric acids were condensed with the silica frame work to form terminal =B-O-Si≡. Above 500 ℃, the condensation proceeded further and boron was fully incorporated into the frame work of =B-O-Si≡. Therefore, the porous borosilicate membrane was obtained by the heat treatment of the gel above 500 ℃. In the 25 ℃∼800 ℃ range, the surface area of sintered gel was between 244.478 m2/g∼648.138 m2/g; the median pore diameter was between 0.0034 μm ∼ 0.0052 μm; and the particle size of sintered gel was between 7 nm∼35 nm.