Abstract
Lignin-based polycaprolactone (LigPCL) copolymer was synthesized by both the ring opening reaction of ϵ-caprolactone with the hydroxyl groups in the lignin and the concomitant polymerization of ϵ-caprolactone. FTIR spectra showed C=O (1755 cm-1) and C-O (1202 cm-1) peaks confirming that the esterification reaction took place successfully between lignin and ϵ:-caprolactone. T2, at which the weight loss of 2% occurs, of pristine lignin and LigPCL were measured as 63 and 211 °C, respectively, and so the synthesized LigPCL had superior thermal stability to the lignin. PP/Lig-PCL blends were prepared at various contents of LigPCL up to 30 wt% by a melt extrusion process. In proportion to the content of the LigPCL, tensile strengths, flexural strengths, and tensile modulus of PP/LigPCL blends greatly decreased, but elongations at break of those greatly increased. To improve the compatibility between PP and LigPCL, maleic anhydride-grafted polypropylene (PP-g-MA) was added. SEM images for the fracture surfaces of the blends showed that the PP-g-MA was effective in reducing the domain size of dispersed phase. Thus, T2, tensile strength, tensile modulus, and elongation at break of a 70/30 blend of PP/LigPCL were enhanced by 6 °C, 17%, 31%, and 79%, respectively, by the addition of PP-g-MA. This work clearly demonstrates that thermoplastic LigPCL could be desirably synthesized and applied for value added and eco-friendly products through common melt processes used for polymer blend or composites manufacturing.
Original language | English |
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Pages (from-to) | 313-320 |
Number of pages | 8 |
Journal | Polymer (Korea) |
Volume | 40 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2016 Mar |
Keywords
- Bioplastics
- Compatiblizer
- Lignin polymer
- Mechanical properties
- Thermal stability
ASJC Scopus subject areas
- Chemical Engineering(all)
- Polymers and Plastics
- Materials Chemistry