Abstract

Crystallization of isotactic polypropylene during step shear rate experiments is carried out in a plate–plate geometry by means of a Linkam shearing cell. The evolution of crystalline structures is observed during the tests at a fixed radial position. The samples are then analyzed by optical microscopy and the radial position at which a transition between the spherulitic and fibrillar morphology took place is measured. The analysis of the samples allows detecting the critical shear rate at which, after a given shearing time, the fibrillar morphology overcomes the spherulitic structure. With the aim of giving a quantitative description of the conditions for the formation of a fibrillar structure, two different models are applied: one based on molecular stretch, the other one relying on specific work.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.