| 초록 |
In general, to enhance physical properties of PET-layered silicate nanocomposites (PetLSNs), it has been well known that the organic modifiers introduce into gallery regions. However, the organic modifiers in PetLSNs may result in thermal decomposition by melt method, and it necessarily lead to deteriorate various physical properties of final products. Therefore, in this study, PetLSNs excluding and including organic modifiers were prepared by solution method (S-PetLSNeom and S-PetLSNiom), and we focused on the effects of the organic modifiers in PetLSNs with exfoliation structure on the crystallization behaviors, the optical transparency, the thermal stability and the mechanical property. The absence and existence of organic modifiers in S-PetLSNeom and S-PetLSNiom were investigated by EA and TGA, and nano-structure of silicate layers in S-PetLSNs was evaluated by using WXRD, SAXS and TEM. S-PetLSNeom and S-PetLSNiom were mixed with neat PET as masterbatches by melt method (M-PetLSNeom and M-PetLSNiom), and also neat PET was mixed with organically modified layered silicates (OLS) by conventional direct melt method (D-PetLSN) at 270 oC. As results, it was found that M-PetLSNeom, M-PetLSNiom, and D-PetLSN exhibited faster crystallization kinetics, better thermal stability and mechanical property than those of neat PET due to the dispersed and delaminated silicate layers in PET matrix. Whereas, considering organic modifiers effect, M-PetLSNiom and D-PetLSN exhibited slower crystallization kinetics, poorer optical transparency, worse thermal stability and lower mechanical property, in comparison to M-PetLSNeom due to the thermal decomposition of organic modifier in PetLSNs during melt method. |
