Computational Approach for Rapidly Predicting Temperature‐Dependent Polymer Solubilities Using Molecular‐Scale Models

Abstract

One promising approach to recycle multicomponent plastic waste (e. g., multilayer plastic films) is selective dissolution. Selective dissolution is a solvent-mediated process in which differences in polymer solubility in a carefully chosen solvent system are exploited to recover a target polymer. Here, a computational approach was developed that rapidly predicts temperature-dependent polymer solubilities to guide the design of solvent systems for solvent-mediated polymer recycling. Polymer conformations were obtained from molecular dynamics simulations by modeling the polymer as a short oligomer and then used as input to the conductor-like screening model for real solvents (COSMO-RS) for solubility predictions. Using polyethylene (PE) and ethylene vinyl alcohol (EVOH) as representative polymers, the effect of simulation parameters was systematically studied, and predicted solubilities were found to be in good agreement with experimental measurements. The applicability of the approach was demonstrated by identifying selective solvents for PE and EVOH dissolution from a library of 524 solvents.

Expanding Plastics Recycling Technologies: Chemical Aspects, Technology Status and Challenges

“…To address this challenge, Zhou et al developed a computational approach for quantitatively predicting temperature-dependent polymer solubilities using molecular-scale models. 679 This approach employs molecular dynamics simulations to sample polymer conformations in representative solvents. These conformations are used as input to the COnductor-like Screening MOdel for Real Solvents (COSMO-RS), a model that used quantum mechanical calculations and statistical thermodynamics methods to predict polymer solubilities through solid-liquid equilibrium calculations.…”

“…These conformations are used as input to the COnductor-like Screening MOdel for Real Solvents (COSMO-RS), a model that used quantum mechanical calculations and statistical thermodynamics methods to predict polymer solubilities through solid-liquid equilibrium calculations. 628,679 After initial polymer conformations are available, temperature-dependent solubilities can be obtained rapidly (~minutes). This approach was applied to screen over 500 solvent combinations for the selective dissolution of PE and EVOH and extended to develop a STRAP process for a commercial multilayer film with four polymer components.…”

“…This approach was applied to screen over 500 solvent combinations for the selective dissolution of PE and EVOH and extended to develop a STRAP process for a commercial multilayer film with four polymer components. [627][628]679…”

Expanding Plastics Recycling Technologies: Chemical Aspects, Technology Status and Challenges

“…These conformations are used as input to the COnductor-like Screening MOdel for Real Solvents (COSMO-RS), a model that used quantum mechanical calculations and statistical thermodynamics methods to predict polymer solubilities through solid-liquid equilibrium calculations. 609,660 After initial polymer conformations are available, temperature-dependent solubilities can be obtained rapidly (~minutes). This approach was applied to screen over 500 solvent combinations for the selective dissolution of PE and EVOH and extended to develop a STRAP process for a commercial multilayer film with four polymer components.…”

“…To address this challenge, Zhou et al developed a computational approach for quantitatively predicting temperature-dependent polymer solubilities using molecular-scale models. 660 This approach employs molecular dynamics simulations to sample polymer conformations in representative solvents. These conformations are used as input to the COnductor-like Screening MOdel for Real Solvents (COSMO-RS), a model that used quantum mechanical calculations and statistical thermodynamics methods to predict polymer solubilities through solid-liquid equilibrium calculations.…”