Limited Time Offer

Claim a 40% discount on your eLearning courses and webinars purchases with code DEALS40.

Offer is valid from November 21-28. Offer excludes instructor-led courses and credential programs.

Strategy for Reducing Molecular Ensemble Size for Efficient Rheological Modeling of Commercial Polymers

  • Type:
    Conference Presentation
  • Checkout

    Checkout

    Do you already own this?

    Pricing


    Individuals

    AIChE Member Credits 0.5
    AIChE Members $19.00
    AIChE Graduate Student Members Free
    AIChE Undergraduate Student Members Free
    Non-Members $29.00
  • Conference Type:
    AIChE Annual Meeting
  • Presentation Date:
    November 9, 2021
  • Duration:
    15 minutes
  • Skill Level:
    Intermediate
  • PDHs:
    0.50

Share This Post:

We develop a method for quantitative predicting the linear and nonlinear rheology of polydisperse polymers by selecting a small number of representative polymer molecules from the large ensemble of chains comprising the overall polymer. Specifically, we use a numerical inversion of the Double Reptation model to select a representative molecular ensemble composed of less than ten molecular species by optimally fitting the linear rheology of polydisperse polymers, and then use the regressed parameters to compute the nonlinear rheology via the Rolie-Double-Poly (RDP) model [1]. After successfully capturing the linear rheology of linear low-density polyethylene (LLDPE) and of low-density polyethylene (LDPE), the method then successfully predicts the linear rheology of blends of the two using the same representative molecules found by fitting each of the pure polymers. Further fitting the extensional rheology of the LDPE required using the “priorities” and stretch relaxation times of the representative molecules as adjustable parameters, which were then held fixed when predicting the extensional rheology of blends of the LDPE with the LLDPE roughly as successfully as does the “Branch-on-Branch” model [3]. The reduction in the number of representative polymer species offers new opportunities for faster simulations of flowing polymers, as well as for prediction of segmental orientation to be used in the modeling of flow-induced crystallization.

[1] V. A. H. Boudara, J. D. Peterson, L. G. Leal, and D. J. Read, Nonlinear Rheology of Polydisperse Blends of Entangled Linear Polymers: Rolie-Double-Poly Models, Journal of Rheology 63, 71 (2018).

[2] H. Münstedt, Dependence of the Elongational Behavior of Polystyrene Melts on Molecular Weight and Molecular Weight Distribution, Journal of Rheology 24, 847 (1980).

[3] C. Das, D. J. Read, D. Auhl, M. Kapnistos, J. den Doelder, I. Vittorias, and T. C. B. McLeish, Numerical Prediction of Nonlinear Rheology of Branched Polymer Melts, Journal of Rheology 58, 737 (2014).

Presenter(s): 
Once the content has been viewed and you have attested to it, you will be able to download and print a certificate for PDH credits. If you have already viewed this content, please click here to login.

Checkout

Checkout

Do you already own this?

Pricing


Individuals

AIChE Member Credits 0.5
AIChE Members $19.00
AIChE Graduate Student Members Free
AIChE Undergraduate Student Members Free
Non-Members $29.00
Language: