Polyamides from Biomass Derived Monomers

Polyamide resins are linear condensation polymers with a high degree of crystallinity with repeating amide (-CO-NH-) links in their molecular chain. The number of carbon atoms between the amide bonds in the main backbone designates the number after the prefix PA . There are, however, two distinct types of polyamides with the following chemical formulas [1]  

Monadic (or AB) polyamides are based upon a single repeating lactam with, on the one end an amine reactive group, and on the other end a carboxylic acid group. The lactam thus reacts with itself and the number describes the lactam involved. Dyadic (or AABB) polyamides are based on the reaction of a diamine and a diacid. The diamine and the diacid react alternatively with each other in a salt solution. In regards to the nomenclature, the first number describes 

Bio-Based Plastics Materials and Applications, First Edition. Edited by Stephan Kabasci. 2014 Jdin WQey Sons, Ltd. Published 2014 by John Wiley Sons, Ltd. 

Although, the lactams are limited to certain geometrically stable ring structures, in theory nearly any combination of an amide and carboxylic acid monomer could create a polyamide. In practice, however, only several major petro-based and bio-based types have been established. 

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Where do Polyamides from Biomass Derived Monomers Fit ... 

Presently, all polyamides produced from biomass derived monomers are based on those monomers derived from castor oil. To a large extent, the price of bio-polyamides will thus be directly influenced by the castor oil price. Such price formulas in addition to the moderate economy-of-scale options and logistics will likely keep bio-polyamides in the upper price range. 

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