Polyfuran Foams

One of the most promising methods of foam preparation starts from polyreactive oligomers which are obtained by polycondensation of 2-furfuryl alcohol, which is subsequently hardened  

It is known that soluble reactive oligomers may be obtained by polycondensation of 2-furfuryl alcohol in the presence of acidic catalysts  

The products of furfuryl alcohol polycondensation contain ether bonds belonging to diforfurylic ether and possibly also to terminal groups of the oligomer  

Strength, fire resistance and apparent density of polyfuran foams depend on the composition of the mixture, amount and type of filler. By varying these parameters, foamed materials may be obtained with 7 = 20-100 kg/m or higher. The fire resistance of these materials is better than that of foamed phenoplastics and polyiso-cyanurate foams, and the mechanical strength is higher than that of carbamide foams. 

Among promising oligomeric foams one should also mention 2-pyranyl foams for a discussion of the chemistry, technology and properties of these materials see Finally, several works concerned with the preparation of foams from cumaron-indene and aniline-formaldehyde oligomers have been reported  

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