On the crystal growth kinetics of ultra‐toughened biobased polyamide 410: New insights on dynamic crystallization

Abstract

The influence of elastomeric poly (octene-co-ethylene) on the crystallization of polyamide 410 in PA-410/POE-g-MA blends was systematically analyzed using a non-isothermal crystallization kinetics approach. A novel power-law criterion was employed to characterize the crystallization regimes (primary and secondary) as a function of cooling rate to understand the nature of crystal arrangement vis-a-vis various kinetic models proposed by Avrami, Jeziorny (modified Avrami method), Ozawa and Liu-Mo. The activation energy pattern with fractional crystallinity from onset to fully developed crystals is discussed as per Friedman's theory. The POE phase acted as a weak nucleating agent for PA 410. The effect of elastomer on crystallization rate constant remained almost unchanged regardless of the blend composition. This insensitivity is attributed to (1) nucleating effect of POE-g-MA (because of resemblance in the molecular scheme) and (2) hindrance effect through the formation of an interfacial network; these two effects nearly offset one another. Our study illustrates the crucial dependence of acceleration of cooling that is, acceleration required for attaining a certain fraction of crystallinity with composition (threshold elastomer concentration), on an interfacial network in binary blends.

The Effect of Cooling Rates on Thermal, Crystallization, Mechanical and Barrier Properties of Rotational Molding Polyamide 11 as the Liner Material for High-Capacity High-Pressure Vessels

“…Mo and Liu et al [ 31 , 32 , 37 ] elaborated a combined Avrami–Ozawa equation to characterize the non-isothermal crystallization kinetics based on the assumption that the degree of crystallinity is correlated with the cooling rate and crystallization time as follows [ 38 ]: where is the apparent Avrami exponent during the non-isothermal crystallization process, and is the Ozawa exponent. refers to the necessary cooling rate required to achieve a given relative crystallinity at unit crystallization time, which can be used as a parameter for the crystallization rate of polymers.…”

The Role of the Interface of PLA with Thermoplastic Starch in the Nonisothermal Crystallization Behavior of PLA in PLA/Thermoplastic Starch/SiO2 Composites

“…The crystallization kinetics of polymers is a widely accepted means to evaluate their crystallization behavior. Many mathematical models are proposed to clarify the macroscopic evolution of crystallinity for polymers during their crystallization process [ 21 , 22 , 23 , 24 , 25 ]. One of the most frequently used models to describe crystallization kinetics is the Avrami equation with the assumptions of nucleation and geometric growth occurring during the crystallization process of the polymers [ 26 , 27 , 28 , 29 ].…”