Preparation of PLA-CNT Nanocomposites

Among the applications discussed in this chapter, the most prominent in recent years is CNT-reinforced polymer nanocomposites. The use of CNTs in polymers can provide superior mechanical properties (60). For instance, the addition of 1% CNTs might increase the stiffness of polymers by 10% and increase their resistance to fracture however, improvements in the properties of CNT-reinforced polymers largely depend on the dispersion of CNTs within the polymer matrix and the polymer-CNT interfacial properties. The following section highlights several studies regarding the processing of PLA-CNT nanocomposites. 

Chen et al. used a grafting to technique to synthesize PLLA-MWCNT nanocomposites (64). In this study, MWCNTs were first treated with acid to yield the carboxylic-acid-functionalized MWCNTs (MWCNT-COOH), which subsequently reacted with 

A uniform dispersion with good absorption of PLLA on the surface of MWCNT was observed. 

MWCNT pure MWCNTs. Wu et al. (74) have molded PCL/ PLA-MWCNT ternary composites using melt-compounding and injection-moldingwith both carboxylic-acid-functionalized and non-function-alized MWCNTs. Although no discussion was presented related to dispersion of MWCNTs, it was observed that the carboxylic-acid-functionalized MWCNTs-filled nanocomposites showed better properties compared with non-functionalized ones. 

Wu and Liao (75) also used melt-compounding to process PLA-MWCNT nanocomposites similar to other studies listed above  

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