Journal of Polymers and the Environment

, Volume 26, Issue 11, pp 4221–4232 | Cite as

Improving the Rheological and Mechanical Properties of Recycled PET Modified by Macromolecular Chain Extenders Synthesized by Controlled Radical Polymerization

  • Juan José Benvenuta TapiaEmail author
  • Martin Hernández Valdez
  • Jorge Cerna Cortez
  • Víctor Martin Díaz García
  • Heber Landeros Barrios
Original Paper


In this work, a series of reactive copolymers of glycidyl methacrylate (G), styrene (S) and acrylonitrile (AN), were synthesized through reversible addition-fragmentation chain transfer polymerization and evaluated as macromolecular chain extenders in reactive extrusion of recycled poly(ethylene terephthalate) (rPET). The results obtained indicate that the addition of the reactive copolymers as chain extenders modifies the chain conformation in rPET causing low crystallization rate and low crystallinity. The physical and rheological properties (melt flow and intrinsic viscosity) of chain-extended rPET improved, rendering better processability. rPET modified with polymeric chain extenders shows improved rheological properties (complex viscosity, storage and loss modulus) and also displays higher elongation at break and impact properties as the GMA content in the chain extenders increase.


Polyethylene terephthalate Rheological properties RAFT polymerization Reactive copolymers 



We acknowledge the technical support of Francisco Méndez and Luis Reyes from Resirene Applications Laboratory.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Juan José Benvenuta Tapia
    • 1
    Email author
  • Martin Hernández Valdez
    • 2
  • Jorge Cerna Cortez
    • 3
  • Víctor Martin Díaz García
    • 2
  • Heber Landeros Barrios
    • 2
  1. 1.Departamento de Ingeniería Química, Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoMexico CityMexico
  2. 2.Departamento de Desarrollo de Productos y ProcesosResirene S.A.XicohtzincoMexico
  3. 3.Facultad de Ciencias QuímicasBenemérita Universidad Autónoma de PueblaPueblaMexico

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