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3.3.2.2 Properties of Poly(Ester‐Amide)s

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Poly(ester‐amide)s are, like poly(ester‐urethane)s, amorphous polymers, but provide an interesting alternative to other biodegradable polyesters due to the incorporated oxamide linkage in the polyester backbone. This feature equips the polymer with different mechanical properties as well as stability when compared to poly(ester‐urethane)s. A slightly higher mechanical strength and lower elongation have their origin in the rigid configuration of the linking agent. The presence of the oxamide linkage affects both the hydrolytic and the thermal stability. The blocking of the terminal groups reduces the melt degradation, and the increased hydrophilicity speeds up the hydrolytic degradation [55, 71, 73]. Poly(ester‐amide)s undergo biodegradation well in the time framework stipulated in the norms. The ecotoxicity issue observed for the poly(ester‐urethane)s prepared by 1,6‐hexamethylenediisocyanate can also be avoided if 2,2′‐bis(2‐oxazoline) is used as the chain extender [67].

Poly(lactic acid)

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