Journal of the Korean Industrial and Engineering Chemistry, Vol.14, No.4, 440-444, June, 2003
PCL/MMT 나노복합재료의 제조와 특성에 관한 연구
Synthesis and Characterization of PCL/MMT Nanocomposites
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초록
본 연구에서는 나노복합재료의 열안정성과 기계적 계면 물성을 향상시키기 위해 몬모릴로나이트 (montmorillonite, MK)를 각각 cetyltrimethylammonium chloride (CTMA-MK)와 dodecylammonium chloride (DA-MK)를 이용하여 유기적으로 개질하였다. MMT의 표면 구조적 특성은 XRD, FT-IR, 그리고 접촉각 측정을 통해 알아보았고, 나노복합재료의 열안정성과 기계적 계면 특성은 TGA와 Gmc를 통해 조사하였다. 실험결과, XRD로부터 유기적으로 개질된 MMT (CTMA-MK와 DA-MK)의 실리케이트 층간이 약 3.9 Å과 7.3 Å의 증가를 보였고, 또한 FT-IR 결과로부터 MK를 제외한 유기적으로 개질된 MMT는 2800 ~ 2900 cm-1에서 CH2의 새로운 피크를 확인할 수 있었다. 유기적으로 개질한 CTMA-MK와 DA-MK의 비극성요소의 감소는 실리케이트 층간의 van der Waals 힘의 감소로 인한 것으로 사료된다. 또한, PCL/CTMA-MK (or DA-MK) 나노복합재료는 PCL/MK에 비해 열분해 초기온도 (IDT), 열분해 활성화 에너지 (Et), 그리고 인열에너지 (Gmc)값이 더 높은 값을 가짐을 알 수 있었다. 이러한 결과는 층간이 증가된 실리케이트에 PCL이 쉽게 삽입되기 때문으로 사료된다.
In this work, montmorillonite (MK) was organically modified with cetyltrimethylammonium chloride (CTMA-MK) and dodecylammonium chloride (DA-MK) to improve thermal stability and mechanical interfacial property of the nanocomposites, respectively. The surface and structure properties of MMT were determined by X-ray diffraction (XRD), FT-IR, and contact angle measurement. Also, thermal stability and mechanical interfacial property of the nanocomposites were investigated by thermogravimetric analysis (TGA) and tearing energy (Gmc). XRD results showed that the silicate interlayers of the organically modified CTMA-MK and DA-MK were, respectively, increased by about 3.9 Å and 7.3 Å, as compared to the as-received MK. Also, FT-IR data showed a new peak appeared at 2800 ~ 2900 cm-1 due to the CH2 mode in the organoclay rather than that of MK. London dispersion force (γL) of organically modified MMT was decreased, resulting in a decrease in van der Waals force between silicate interlayers. It was found that the PCL/organically modified MMT (DA-MK and CTMA-MK) nanocomposites had higher initial decomposition temperature (IDT), decomposition activation energy (Et), and tearing energy (Gmc) values than those of PCL/MK. These results explained why the PCL was inserted easily in the increased spacing of the silicate interlayers.
Keywords:montmorillonite;poly(ε-caprolactone);surface free energy;thermal stability;mechanical interfacial property
- Theng EKG, Formation and Properties of Clay-polymer Composites, Elsevier, New York (1979)
- Diez-Gutierrez S, Rodriguez-Perez MA, De Saja JA, Velasco JI, Polymer, 40(19), 5345 (1999)
- Park SJ, Jin JS, J. Appl. Polym. Sci., 82(3), 775 (2001)
- Larena A, Villar MA, Opt. Mater., 17, 437 (2001)
- Kornmann X, Lindberg H, Berglund LA, Polymer, 42(4), 1303 (2001)
- Park SJ, Kim MH, J. Mater. Sci., 35(8), 1901 (2000)
- Bujdak J, Hackett E, Giannelis EP, Chem. Mater., 12, 2168 (2000)
- Park SJ, Seo DI, Nah C, J. Colloid Interface Sci., 251(1), 225 (2002)
- Langer R, Science, 249, 1527 (1990)
- Park SJ, Seo DI, Lee JR, J. Colloid Interface Sci., 251(1), 160 (2002)
- Tseng CR, Wu JY, Lee HY, Chang FC, Polymer, 42(25), 10063 (2001)
- Jimenez G, Ogata N, Kawai H, Ogihara T, J. Appl. Polym. Sci., 64(11), 2211 (1997)
- Ogata N, Kawakage S, Ogihara T, Polymer, 38(20), 5115 (1997)
- Park SJ, Kim JS, J. Colloid Interface Sci., 232(2), 311 (2000)
- Pinnavaia TJ, Science, 220, 365 (1983)
- Whitesides GM, Mathias TP, Seto CT, Science, 254, 1312 (1991)
- Vaia RA, Teukosky RK, Giannelis EP, Chem. Mater., 6, 1017 (1994)
- Fowkes FM, J. Phys. Chem., 66, 385 (1962)
- VanOss CJ, Ju L, Chaudhury MK, Good RJ, J. Colloid Interface Sci., 128, 315 (1989)
- Horowitz HH, Metzger G, Anal. Chem., 35, 1464 (1963)
- Greensmith HW, J. Appl. Polym. Sci., 3, 183 (1960)
- Park SJ, Kim JS, Carbon, 39, 2011 (2001)