A biopolymer derived from castor oil polyurethane: Experimental and numerical analyses

• Type: Chapter or Part of a Book
• Date: 2017

Authors

Romeu Rony Cavalcante da Costa (Author) Other; André C. Vieira (Author) Other; Rui Miranda Guedes (Author) FEUP; Volnei Tita (Author) Other

Book

Title: Handbook of Composites from Renewable Materials

Pages: 581-606

ISBN: 9781119441632; 9781119223627

Indexing

Scopus - 1 Citation

Other information

Authenticus ID: P-00S-0RC

DOI: 10.1002/9781119441632.ch60

Abstract (EN): This chapter presents experimental and numerical analyses for a new biopolymer derived from renewable source, the castor oil (Ricinus communis). Mechanical tests comprise quasi-static tensile loading, compression and bending (monotonic and cyclic) loading, and dynamic mechanical analysis (DMA). Experimental results show moderate strains above yielding. A large portion of strain consists on irreversible deformations, which remained after removal of stresses. A part of the irreversible deformations is due to viscous flow and is progressively accumulated if the stress is maintained. The elastic part of reversible deformation is immediately recovered when the material is unloaded, while the other part takes some time to recover. Besides, the biopolymer mechanical response is very sensitive to the strain rate. For the numerical analyses, two constitutive models are investigated: a bilinear elastoplastic isotropic hardening model, frequently referred as J2 flow theory, and the modified Bergstrom-Boyce viscoplastic model. The parameters of models are identified by using a calibration process. Numerical simulations are discussed to assess the potentialities and limitations of the models in order to reproduce the biopolymer behavior. At last, the viscoplastic model simulates the biopolymer mechanical behavior more accurately than the elastoplastic model. © 2017 Scrivener Publishing LLC.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 26