<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Ecopolyol Production from Industrial Cork Powder via Acid Liquefaction Using Polyhydric Alcohols</style></title><secondary-title><style face="normal" font="default" size="100%">ACS SUSTAINABLE CHEMISTRY &amp; ENGINEERING</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2014</style></year></dates><publisher><style face="normal" font="default" size="100%">AMER CHEMICAL SOC</style></publisher><pub-location><style face="normal" font="default" size="100%">1155 16TH ST, NW, WASHINGTON, DC 20036 USA</style></pub-location><volume><style face="normal" font="default" size="100%">2</style></volume><pages><style face="normal" font="default" size="100%">846-854</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Ecopolyol production from acid liquefaction of cork powder was studied&lt;br/&gt;for the first time using PEG 400 and glycerol as liquefaction solvents&lt;br/&gt;in the presence of sulfuric acid at moderate temperature and atmospheric&lt;br/&gt;pressure. The effect of the temperature, concentration of catalyst, and&lt;br/&gt;time on the liquefaction yield has been investigated using a fixed set&lt;br/&gt;of reaction conditions namely, a liquefaction solvent mixture/cork&lt;br/&gt;powder ratio of 5/1 and a solvent mixture PEG 400/glycerol ratio of&lt;br/&gt;90/10. The full-factorial design of experiments (DOE) 23 was applied to&lt;br/&gt;obtain an optimized set of liquefaction conditions aiming at minimizing&lt;br/&gt;the residue content. The minimum residue contents experimentally&lt;br/&gt;obtained in this study were 29 wt %, related to cork powder, which were&lt;br/&gt;achieved at 150 C, 4 wt % of sulfuric acid, and 60 min. This value&lt;br/&gt;corresponds to 5 wt % of residue per total mass of reaction product.&lt;br/&gt;The polyols obtained under optimal conditions present similar&lt;br/&gt;characteristics (hydroxyl number value 219 mg(KOH)/g(polyol) and&lt;br/&gt;viscosity 2875 cP, at 25 degrees C) to those of petroleum-based polyols&lt;br/&gt;typically used in the polyurethane foam industry.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Rigid polyurethane foams derived from cork liquefied at atmospheric pressure</style></title><secondary-title><style face="normal" font="default" size="100%">Polymer International</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2014</style></year></dates><publisher><style face="normal" font="default" size="100%">John Wiley &amp; Sons, Ltd.</style></publisher><pages><style face="normal" font="default" size="100%">n/a--n/a</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The aim of this study was to evaluate the possibility of using polyols derived from liquefied cork in the production of novel bio-based polyurethane foams (PUFs). For that purpose, different liquefaction conditions were used at atmospheric pressure and moderate temperature where poly(ethylene glycol) and glycerol were used as solvents and sulfuric acid as catalyst. The ensuing polyols were used to produce foams which were characterized using structural, morphological, thermal and mechanical analyses to demonstrate that liquefaction conditions play a crucial role in the properties of the foams. The resulting foams exhibited the typical cellular structure of PUFs with low densities (57.4–70.7 kg m−3) and low thermal conductivities (0.038–0.040 W m−1 K−1). However, the mechanical properties differed significantly depending on the liquefaction conditions. The best stress–strain results were obtained for PUFs prepared using the polyol with lowest IOH and water content (Young's modulus of 475.0 kPa, compressive stress (σ10%) of 34.6 kPa and toughness of 7397.1 J m−3). This PUF was thermally stable up to 200 °C and presented a glass transition temperature of around 27 °C. The results obtained demonstrate that these polyols from liquefied cork yield PUFs that are adequate materials for insulation applications. © 2014 Society of Chemical Industry</style></abstract></record></records></xml>