Modeling of Polyamide 66 Solid State Polymerization: Drawing a Chemical Reaction Scheme

Abstract

A chemical reaction scheme is proposed here to describe the polyamide 66 (PA 66) solid state polymerization (SSP) with effective kinetic parameters. The main objective of the suggested model is to predict the maximum molecular weight attainable at each SSP isotherm, which is in turn determined by the occurrence of polymer chain degradation coupled to other important side reactions. Accordingly, a number of side reactions have been firstly considered, based on which a comprehensive particle model was constructed to predict PA 66 kinetics, equilibrium, and transport phenomena. The SSP model parameters were estimated with a maximum-likelihood estimator, using data measured under kineticand diffusion-controlled process conditions for reaction temperatures in the range of 160-200 8C and reaction times up to 8 h. Calibration models were also developed to allow the determination of PA 66 solution viscosities.

Molecular simulation of diffusion-controlled kinetics in stepwise polymerization

“…Kline et al [59] found that the controlling factor switched from kinetics to diffusion when the degree of polymerization was greater than 25 and the extent of reaction was greater than 0.923. Filgueiras [60] described the solid state polymerization of polyamide-6,6 with effective kinetic parameters under diffusion-controlled process, where the deviation from second order kinetics could be observed when p＞0.93.…”

Mechanism Study of the Polymerization of Polyamide 56: Reaction Kinetics and Process Parameters

“…Moreover, the polymerization of high-quality PA56 is also challenging due to the volatile, ring-forming, N-methylation, and weak alkalinity characteristics of PDA. [39][40][41][42] Therefore, a detailed exploration of the polymerization reaction mechanism is crucial to achieve high-performance partially bio-based PA56.…”