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PREPARATION AND CHARACTERIZATION OF BIODEGRADABLE RIGID POLYURETHANE FOAMS FROM THE LIQUEFIED EUCALYPTUS AND PINE WOODS
(Slovak Forest Products Research Inst, 2014) Ertaş, Murat; Fidan, Muhammed Said; Alma, Mehmet Hakki
In this study, eucalyptus (Eucalyptus camaldulensis L.) and pine (Pinus sylvestris L.) woods were liquefied using the the blended solvents mixture of polyethylene glycol PEG-400/glycerin in the presence of sulfuric acid as a catalyst at 140-160 degrees C for 120 min. The insoluble parts in the liquefied eucalyptus and pine were found as 17.8 and 5.5 wt. %, respectively. The acid and hydroxyl numbers of the liquefied eucalyptus and pine were determined and compared with each other. Polyurethane-type rigid foams (RPUFs) were successfully prepared by a co-polymerization of the liquefied woods (LWs) and polymeric methylene diphenylene diisocyanate (PMDI). The compressive strength (120 to 250 kPa), the modulus of elasticity (1 to 6 MPa), the density (20 to 50 kg.m(-3)) and thermal conductivity (0.0352 to 0.0374 W.mK(-1)) of the RPUFs prepared from the LWs were found to be almost comparable to those of the synthetic foams. Furthermore, the biodegradability of the biomass-based foams was higher than that of the synthetic ones.