Using a Multiscale Modeling Approach to Correlate Reaction Conditions with Polymer Microstructure and Rheology. Issue 1 (28th October 2020)

• Record Type: Journal Article
• Authors: Zentel, Kristina M.; Degenkolb, Jonas; Busch, Markus
• Is Part Of: Macromolecular theory and simulations. Volume 30:Issue 1(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-28
• Subjects: long‐chain branching -- low‐density polyethylene -- multiscale modeling -- structure‐property relationships; Macromolecules -- Periodicals; Polymers -- Periodicals; Polymerization -- Periodicals; Macromolécules -- Périodiques; 547.705
• DOI: 10.1002/mats.202000047
• Languages: English
• ISSNs: 1022-1344

Abstract

Abstract: Reaction conditions have a huge impact on the resulting polymer properties, but capturing this requires understanding the correlation of the underlying kinetics, the polymer architecture, and polymer flow behavior. Long‐chain branched polymers created randomly by free‐radical polymerization, such as low‐density polyethylene (LDPE), show complex rheological behavior and are thus interesting in this context. A study applying a multiscale modeling approach is used to simulate varying reaction conditions and predict the structure of the resulting LDPE polymer and its flow properties. A significant effect on the molecular weight distribution, but also the viscosity and extensional flow behavior can be predicted. Higher conversions, for example, lead to broader molecular weight distributions, increased long‐chain branching degrees, and a higher branching complexity. Consequently, also higher viscosities and increased strain hardening are observed in extension. Additionally, miniplant experiments are performed to resemble the simulations and compare the results. The accordance of predictions and analytical results are very good and validate the model over a wide range of reaction conditions. Abstract : Low‐density polyethylene polymer properties and flow behavior are modeled via a three‐step multiscale modeling approach in order to assess and quantify the effect of varying reaction conditions. Significant effects on the molecular weight distributions, branching complexity, and (extensional) viscosities are predicted. After a detailed sensitivity study, the simulation results are successfully validated with a broad set of miniplant experiments.