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Polyols for rigid PU foams production are derived mostly from petrochemical products but it can be replaced by polyols obtained from natural raw materials (vegetable oils, tall oil, lignin etc.). Organosolve lignin from CIMV biorefinery (France) was used in our work. Different lignin and propylene oxide (PO) ratio (0.15-0.40) was used to get lignopolyols. Commercial polyol Lupranol 3300 was substituted by each lignopolyol in the compositions of rigid PU foams to investigate lignopolyol effect to density, closed cell content, physical-mechanical properties and water absorption. Lignopolyols synthesized from CIMV lignin by oxypropylation reaction is prospective material to obtain rigid PU foam with improved characteristics such as water absorption and compression strength.

Due to development of new generation of biomass processing, the examination of novel lignin products for creation of lignin-containing PU remains actual up to now. For preparation of lignin containing PU in this study a novel BIOLIGNIN was used. BIOLIGNIN is extracted from wheat straw in organic acid media using biomass refinery technology. The influence of chemically non-modified BIOLIGNIN and oxypropylated BIOLIGNIN on flammability and thermal properties in rigid PU foams was studied. Improvement of flame resistance and thermal stability is observed if chemically non-modified lignin as well as oxypropylated lignin is used.

Different separate approaches of CIMV lignin introduction into PUR foam system were studied: as filler without chemical preprocessing and as liquid lignopolyol obtained by lignin oxypropylation in alkali conditions. The incorporation of increasing amount of lignin as filler into reference PUR foam systems on the basis of mixture of commercial polyethers Lupranol 3300 and Lupranol 3422 steadily decreased the compression characteristics of foams, their dimensional stability and hydrophobicity. The complete substitution of Lupranol 3300 by lignopolyol increases its cell structure uniformity and dimensional stability and does not reduce the physical-mechanical properties of foam.

Nowadays, the synthesis of polymers from renewable resources, including polyurethane foams, has been actively investigated. In this work the potential application of lignin (CIMV, France) as non-reactive filler in tall oil amide (OH = 269 mg KOH/g, H2O = 0,2 wt.%) based rigid PU foams is studied. It was concluded that introducing lignin to rigid PU foams systems can increase physico-mechanical properties of foams.

Nowadays, due to economical and environmental concerns, polyurethane (PU) elastomer and rigid foam industry seeks ways to replace petrochemical polyols by renewable biomass. The aim of this study was to investigate lignin as a co-polyol in a solvent free production of castor oil based PU elastomers and tall oil amide based rigid PU foams. Lignin content correlation influence on PU elastomers and PU rigid foam physical-mechanical and morphological parameters were determinate.