Ananda S. Amarasekara^*, Muhammad A. Hasan, Eve Larkin

Journal of Renewable Materials, Vol.5, No.1, pp. 62-66, 2017, DOI:10.7569/JRM.2016.634129

Abstract Condensation polymerization of renewable resources-based monomers, 4-ketopimelic acid and glycerol, were studied using two different catalysts; p-toluenesulfonic acid and Sb2O3. The highest polymer yield of 96% was achieved by using a 3:4 mole ratio mixture of 4-ketopimelic acid and glycerol, with Sb2O3 (0.5 mol% relative to 4-ketopimelic acid) as catalyst and heating at 23–210 °C, under N2 for 1 h; then 210 °C, vacuum, 12 h. The poly(4-ketopimelic acid-glycerol) formed is insoluble in all common organic solvents and is shown to contain a branched polymeric structure with ketal and ester links by using FT-IR, 1H and 13C NMR spectroscopy. More >

Facundo I. Altuna¹, Borja Fernández-d’Arlas², M. Angeles Corcuera², Arantxa Eceiza², Mirta I. Aranguren³, Pablo M. Stefani^3*

Journal of Renewable Materials, Vol.4, No.4, pp. 275-284, 2016, DOI:10.7569/JRM.2016.634120

Abstract Mixtures of biomass-derived polyols were used to synthesize rigid polyurethane (PU) foams. A commercial polymerized methylene diphenyl diisocyanate (pMDI) was used as crosslinker, and distilled water served as foaming agent. The morphology and mechanical properties of foams with different glycerol and water contents were compared in order to evaluate the most suitable formulations. The rigid foams with higher water contents had larger and more anisotropic cells, explaining their lower density. Compressive moduli ranged from about 2.5 MPa to above 20 MPa and collapse stresses from 55 kPa to more than 1 MPa for densities between 54 and 143 kg/m3. Densification… More >

Piotr Rojek², Mirta I. Aranguren¹, Aleksander Prociak², Mirna A. Mosiewicki^1*

Journal of Renewable Materials, Vol.4, No.4, pp. 266-274, 2016, DOI:10.7569/JRM.2016.634113

Abstract Solid biobased polyurethanes (PUs) were prepared from a rapeseed oil-based polyol (ROPO) synthesized by epoxidation reaction followed by oxirane ring-opening with diethylene glycol. The reference material was modified by replacement of the ROPO with glycerol in different proportions and also by addition of commercial microcellulose (MC). The curing process of the reactive mixtures was monitored by rheological measurements and the analysis showed that both MC and glycerol increase the time of crossover between storage and loss modulus (liquid to solid transition in the response at 1 Hz). The completely cured polyurethanes were characterized by physical, morphological and mechanical analysis. The… More >