초록 |
Multiwalled carbon nanotubes (MWCNT) were functionalized with poly(L-lactic acid) (PLLA) with different molecular weights using the “grafting to” technique. The oxidized MWCNT were converted to the acyl-chloride-functionalized MWCNT by treating them with thionyl chloride and reacting them with PLLA to prepare the MWCNT-g-PLLA. FTIR and Raman spectroscopy revealed that the PLLA was covalently attached to the MWCNT, and the weight gain due to the functionalization was determined by thermogravimetric analyses. The amount of grafted PLLA depended on the molecular weight of the PLLA. The PLLA coated on the MWCNT became thicker and more uniform with increasing PLLA molecular weight from 1000 to 3000. However, the amount of grafted PLLA became lower when the molecular weight of PLLA was further increased to 11 000 and 15 000, and the PLLA attached to the MWCNT showed a squid leg-like morphology forming blobs and leaving much of the MWCNT surface bare. |