Publicação
Oxypropylation of lignins and characterization of the ensuing polyols
| Resumo: | Four lignin samples (Alcell, Indulin AT, Curan 27-11P and Sarkanda) were converted into liquid polyols by a chain extension reaction with propylene oxide (oxypropylation). The reaction was carried out in a batch reactor using potassium hydroxide (KOH) as a catalyst. The oxypropylation process was first optimized with Alcell lignin by modifying the lignin/propylene oxide ratio (L/PO, w/v) and catalyst content (C/(C+L), % w/w). L/PO ratios of 10/90, 20/80, 30/70 and 40/60, and catalyst contents from 2 to 5% were used. Based on the studied formulations, and considering the polyol requirements for polyurethane foam synthesis (a hydroxyl number (IOH) between 300 and 800 and a viscosity below 300 Pa.s), three formulations were chosen and applied for the oxypropylation the other lignin samples: 20/80/5, 30/70/2 and 35/65/2. The produced polyols were characterized. Their IOH and viscosity were found to be in the range of those typical of commercial polyols employed in polyurethane preparation. |
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| Autores principais: | Cateto, Carolina |
| Outros Autores: | Barreiro, M.F.; Rodrigues, Alírio; Belgacem, Mohamed Naceur |
| Assunto: | Lignin Oxypropylation Biopolyols Characterization |
| Ano: | 2007 |
| País: | Portugal |
| Tipo de documento: | comunicação em conferência |
| Tipo de acesso: | acesso restrito |
| Instituição associada: | Instituto Politécnico de Bragança |
| Idioma: | inglês |
| Origem: | Biblioteca Digital do IPB |
| Resumo: | Four lignin samples (Alcell, Indulin AT, Curan 27-11P and Sarkanda) were converted into liquid polyols by a chain extension reaction with propylene oxide (oxypropylation). The reaction was carried out in a batch reactor using potassium hydroxide (KOH) as a catalyst. The oxypropylation process was first optimized with Alcell lignin by modifying the lignin/propylene oxide ratio (L/PO, w/v) and catalyst content (C/(C+L), % w/w). L/PO ratios of 10/90, 20/80, 30/70 and 40/60, and catalyst contents from 2 to 5% were used. Based on the studied formulations, and considering the polyol requirements for polyurethane foam synthesis (a hydroxyl number (IOH) between 300 and 800 and a viscosity below 300 Pa.s), three formulations were chosen and applied for the oxypropylation the other lignin samples: 20/80/5, 30/70/2 and 35/65/2. The produced polyols were characterized. Their IOH and viscosity were found to be in the range of those typical of commercial polyols employed in polyurethane preparation. |
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