Table 9.
Results summary and explanation.
| Blend system | Compatibilizer (PLLA-b-PE) | Impact strength (J/m) | Explanation |
|---|---|---|---|
| a-PLA | – | 12 | |
| a-PLA/LLDPE (80wt%/20wt%) | – | 34 | |
| a-PLA/LLDPE (80wt%/20wt%) | 5 wt%a | 36 | The difference is attributed to superior ability of the PLLA-b-PE from the longer PLLA block to suppress the coalescence of the dispersed phase |
| a-PLA/LLDPE (80wt%/20wt%) | 5 wt%b | 460 | |
| PLLA | – | 20 | |
| PLLA/LLDPE (80wt%/20wt%) | – | 350 | Adhesion test showed a superior interfacial adhesion when used semicrystalline PLLA instead of amorphous a-PLA |
| PLLA/LLDPE (80wt%/20wt%) | 5 wt%a | 510 | The tacticity effects on either the Mc of PLA or the miscibility degree of PLA matrix with LLDPE phase accounted for the difference between the two binary blends |
| PLLA/LLDPE (80wt%/20wt%) | 5 wt%b | 660 |
a-PLA, amorphous PLA; PLLA, semicrystalline PLA; LLDPE, linear low density polyethylene.
a
The molecular weight of PLLA block in PLLA-b-PE is 5 kg/mol < Mc = 9 kg/mol.
b
The molecular weight of PLLA block in PLLA-b-PE is 30 kg/mol > Mc = 9 kg/mol.
Mc = 9 kg/mol is the critical entanglement molecular weight of PLLA block in PLLA-b-PE.