Oil-Based and Bio-Derived Thermoplastic Polymer Blends and Composites 241
plasticizers, blending with other polymers (developed in the paragraph thermoplastic
blends) and recent study also proposed the use of ionic liquids.
Baiardoet al. [3] analysed the influence of two different plasticizers, in different
percentages: acetyl tri-n-butyl citrate (ATBC) and PEGs with different molecular
weights. Both acted as plasticizers, significantly increasing the elongation at break of
PLA. As reported in the literature, the main problem of plasticizers is the decrease of
tensile strength and tensile modulus; this problem was confirmed by this study and
Table 8.2 displays these results.
Martin and Avérous [4] analysed the effect of different plasticizers such as glycerol,
PEG and oligomeric lactic acid (OLA). Glycerol was the less effective plasticizer, while
Table 8.2Tensile test results of pure PLA and
PLA modified with polyethylene glycol (PEG)
and acetyl tri-n-butyl citrate (ATBC) in different
percentages.
Material 흈b(MPa) E(GPa) 휺b(%)
Pure PLA 66 3.3 1.8
PEG 400 (wt%)
5 41.6 2.5 1.6
10 32.5 1.2 140
12.5 18.7 0.5 115
15 19.1 0.6 88
20 15.6 0.5 71
PEG 1.5 K (wt%)
5 52.3 2.9 3.5
10 46.6 2.8 5
12.5 18.5 0.7 194
15 23.6 0.8 216
20 21.8 0.6 235
PEG 10 K (wt%)
5 53.9 2.8 2.4
10 48.5 2.8 2.8
15 42.3 2.5 3.5
20 22.1 0.7 130
ATBC (wt%)
5 53.4 3.2 5.1
10 50.1 2.9 7
12.5 17.7 0.1 218
15 21.3 0.1 299
20 23.1 0.1 298
Baiardoet al. 2003 [3]. Reproduced with
permission of John Wiley and Sons.
