Maleic Anhydride -g-Polypropylene와 Diamine으로 개질된 Clay를 이용한 Nanocomposites의 합성과 특성결정

초록

Polypropylene/montmorillonite (PP/MMT) nanocomposites were prepared by compounding PP -g-maleic anhydride(MAPP) with MMT modified with α,ω-diaminododecane. The structural characterization confirmed formation of characteristic amide linkage and intercalation of MAPP between the silicate layers. In particular, XRD patterns of the modified clay and MAPP/MMT composites showed 001 basal spacing enlargement as much as 1.49 nm. Thermogravimetric analysis revealed that thermal decomposition of the composite took place at slightly higher temperature than that of MAPP. Melting peak temperature stayed constant and heat of fusion decreased indicating that the crystallization MAPP was suppressed as a results of the compounding. PP/MAPP/MMT composites showed 20-35% higher tensile modulus and tensile strength compared to PP/MAPP blend. However elongation at break decreased drastically even when the content of MMT was as low as 1.25 ~ 5 wt%. The relatively short chain length and loop structure of MAPP bound to the clay layers make penetration of MAPP moecules into PP homopolymer phase implausible, and is though to be responsible for the decreased elongation at break.