Preparation of Polyurethane Adhesives from Crude and Purified Liquefied Wood Sawdust

Sammanfattning

Polyurethane (PU) adhesives were prepared with bio-polyols obtained via acid-catalyzed polyhydric alcohol liquefaction of wood sawdust and polymeric diphenylmethane diisocyanate (pMDI). Two polyols, i.e., crude and purified liquefied wood (CLW and PLW), were obtained from the liquefaction process with a high yield of 99.7%. PU adhesives, namely CLWPU and PLWPU, were then prepared by reaction of CLW or PLW with pMDI at various isocyanate to hydroxyl group (NCO:OH) molar ratios of 0.5:1, 1:1, 1.5:1, and 2:1. The chemical structure and thermal behavior of the bio-polyols and the cured PU adhesives were analyzed by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Performance of the adhesives was evaluated by single-lap joint shear tests according to EN 302-1:2003, and by adhesive penetration. The highest shear strength was found at the NCO:OH molar ratio of 1.5:1 as 4.82 & PLUSMN; 1.01 N/mm(2) and 4.80 & PLUSMN; 0.49 N/mm(2) for CLWPU and PLWPU, respectively. The chemical structure and thermal properties of the cured CLWPU and PLWPU adhesives were considerably influenced by the NCO:OH molar ratio.

Nyckelord

adhesive penetration; bio-polyol; bond strength; ethylene glycol; FTIR; liquefaction; pMDI; TGA

Publicerad i

Polymers
2021, volym: 13, nummer: 19, artikelnummer: 3267

SLU författare

• Adamopoulos, Stergios

  • Institutionen för skogens biomaterial och teknologi, Sveriges lantbruksuniversitet
    

Globala målen (SDG)

SDG12 Hållbar konsumtion och produktion

UKÄ forskningsämne

Polymerteknologi
Trävetenskap

Publikationens identifierare

• DOI: https://doi.org/10.3390/polym13193267

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/113749