12th European Conference on Biomass for Energy, Industry and Climate Pmtection, 17-21 June 2002, Amsterdam, The Netherlands

LIQUEFACTION OF AGRICULTURAL BTOMASS WASTES WITH POLYHYDRIC ALCOHOLS AND ITS APPLICATION TO POLYURETHANE-TYPE FOAMS

M. H. Alma¹, M. A. Baştürk¹, M. Dığrak²

¹Department of Industrial Engineering of Forestr , Faculty of Forestry, University of Kahramanmaras Sütçü Imam Kahramanmaras. 46060 Turkey, Tel: +90 344 223 7666; Fax: ±90 344 225 1442; e-mail: almaksu.edu.tr and mbasturk@hotmail.com.

²Department of Microbiology, Faculty of Art & Science, University of Kahramanmaraş Sütçü Imam Kahramanmaraş 46100 Turkey. Tel: +90 344 251 2315; Fax: +90 344 225 1442; mdigrak@hotmail.com

ABSTRACT              

In the present study, powders of cotton stalk (Gossypium hirsitum L.) and wheat straw (Triticum aestivum L.) were first liquefied with the mixture of polyethylene glycol-40⁰ and glycerin in the presence of sulfUric acid as a catalyst at 1 60⁰C for 60 and 120 mi Polyurethane-type rigid foams from the reaction between cotton and wheat straws liquefied with the polyols above and polymeric diphenylmethane diisocyanate were then successfully prepared by following common methods. The results showed the cotton stalk was liquefied into polyols much more in comparison to wheat straw. It was also determined that polyurethane-type foams could be successfully produced from the liquefied cotton and wheat straws. The hydroxyl values and the amounts of unliquefted biomass decreased by increasing reaction time in contrast to acid value. The compressive strength (93-112 KPa), its elastic modulus (3.0-3.9 MPa) and the density (0.029-0.038 glcm³) of foams made from both liquefied biomass were found to be almost comparable to those of the foams made from commercial polyols. Furthermore, the biodegradability of the biomass-based foams was higher than that of commercial one.

Keywords: polyurethane foams, cotton stalk, wheat straw