TY - JOUR
T1 - Poly(lactic acid)/pulp fiber composites
T2 - The effect of fiber surface modification and hydrothermal aging on viscoelastic and strength properties
AU - Paunonen, Sara
AU - Berthold, Fredrik
AU - Immonen, Kirsi
N1 - Funding Information:
The authors gratefully acknowledge the funding from VTT and RISE.
PY - 2020/11/10
Y1 - 2020/11/10
N2 - Poly(lactic acid) (PLA)/kraft pulp fiber (30 wt%) composites were prepared with and without a coupling agent (epoxidized linseed oil, ELO, 1.5 wt%) by injection molding. The non‐annealed composite samples, along with lean PLA, were exposed to two hydro‐thermal conditions: cyclic 50% RH/90% RH at 23 and 50°C, both up to 42 days. The aging effects were observed by size exclusion chromatography, differential scanning calorimetry, dynamic and tensile mechanical analysis, and fracture surface imaging. ELO temporarily accelerated the material's internal transition from viscous to an increasingly elastic response during the aging at 50°C. ELO also slowed down the tensile strength reduction of the composites at 50°C. These observations were explained with the hydrophobic ELO molecules' coupling and plasticizing effects at fiber/matrix interfaces. No effects were observed at 23°C.
AB - Poly(lactic acid) (PLA)/kraft pulp fiber (30 wt%) composites were prepared with and without a coupling agent (epoxidized linseed oil, ELO, 1.5 wt%) by injection molding. The non‐annealed composite samples, along with lean PLA, were exposed to two hydro‐thermal conditions: cyclic 50% RH/90% RH at 23 and 50°C, both up to 42 days. The aging effects were observed by size exclusion chromatography, differential scanning calorimetry, dynamic and tensile mechanical analysis, and fracture surface imaging. ELO temporarily accelerated the material's internal transition from viscous to an increasingly elastic response during the aging at 50°C. ELO also slowed down the tensile strength reduction of the composites at 50°C. These observations were explained with the hydrophobic ELO molecules' coupling and plasticizing effects at fiber/matrix interfaces. No effects were observed at 23°C.
KW - aging
KW - biopolymers and renewable polymers
KW - cellulose and other wood products
KW - composites
UR - http://www.scopus.com/inward/record.url?scp=85087216834&partnerID=8YFLogxK
U2 - 10.1002/app.49617
DO - 10.1002/app.49617
M3 - Article
VL - 137
JO - Journal of Applied Polymer Science
JF - Journal of Applied Polymer Science
SN - 0021-8995
IS - 42
M1 - 49617
ER -
