MWCNT-PMMA composites effectiveness

Pande et al. (25) also reported significant improvements in the flexural properties of MWCNT-PMMA composites prepared by in-situ polymerization method. They observed a maximum reinforcing effect of CNTs at 3 wt% for a-MWCNT and at 1.8 wt% for f-MWCNT. The flexural strength for the two cases was about 90 MPa as compared to about 64 MPa from two step method... 

Mathur et al. (24) and Pande et al. (44) studied the effect of MWCNT content on the EMI shielding properties of MWCNT-PMMA composite films in the X-band (8.2-12.4 GHz). The MWCNT-PMMA nanocomposites with higher MWCNT content exhibit greater EMI shielding effectiveness (SE) (Figure 7.14). 

Figure 7.14. EMI shielding effectiveness of MWCNT-PMMA composites with different CNT loading. Reprinted with permission from John Wiley Sons, Inc (24).

Figure 7.15. Effect of MWCNT content on SERand SEA of MWCNT- PMMA composite film at 12 GHz. Reprinted with permission from Springer Science and Business Media (44).

Electromagnetic interference shielding effectiveness of about 18 dB was achieved with 10 vol% MWCNT-PMMA film which was found to be primarily an EMI absorbing composite material. Figure 7.15 shows the variation of EMI shielding effectiveness due to reflection... 

Yang et al. 2005 (59) MWCNT CVD Purified In situ polymerization CNT Loading levels 0.05 to 2.5wt% Block Specimens Microhardness increased, friction coefficient decreased and wear rate decreased with increasing CNT content SEM analyses of worn surfaces of PMMA showed the positive effect of CNTs on tribological behavior of composites ... 

FIGURE 1.14 Effects of MWCNT surface functionalization on the bubble density of PMMA CNT nanocomposite foams, (a) Surface functionalization scheme, in which oxidized CNTs (M20 and MlOO) were surface grafted with glycidyl phenyl ether (P20 and PlOO). 20, 100 in the notation refer to the CNT aspect ratio, (b) A comparison of the bubble nucleation density of MlOO, PlOO, M20, and P20 nanocomposites foamed, saturated at various pressures, and foamed at 65°C for 5 minutes. Error bars represent the standard deviations of bubble nucleation density data of four samples under each condition. (Reprinted with permission from Chen L. et al.. Composites Science and Technology 2012, 72, 190-196. Copyright 2012, Elsevier.)... 

A complex multicomponent system based on PMMA and PA6 was developed and processed as fibers by co-axial electrospinning [153]. The co-axial composite nanofibers with a core-shell stmcture embedded Ti02 nanoparticles, as well MWCNTs. When Ti02 nanoparticles were added to the shell, the fibers exhibited a remarkable ability to absorb UV radiation, but a lower transmittance in the visible light range. Using the Ti02 nanoparticles for the core, the effects were reversed. 

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