Unprecedented dependence of stiffness parameters and crystallinity on comonomer content in rapidly cooled propylene-co-1-pentene copolymers Articles uri icon

publication date

  • November 2017

start page

  • 17

end page

  • 25

volume

  • 130

International Standard Serial Number (ISSN)

  • 0032-3861

Electronic International Standard Serial Number (EISSN)

  • 1873-2291

abstract

  • A thorough evaluation of the mechanical behavior exhibited by fast crystallized propylene-1-pentene copolymers, synthesized in a broad range of 1-pentene compositions, is here described. Different mechanical magnitudes derived from loading, creep and unloading processes in depth sensing indentation measurements are correlated to structural features. Several ordered forms are able to be developed applying a fast cooling processing at the composition interval analyzed in these propylene-1-pentene copolymers. Moreover, either a single polymorph or distinct ratios of two crystalline lattices can be obtained, depending on comonomer content. Crystallinity as well as the type of existing crystallites play a critical role in the value of those mechanical magnitudes. An uncommon dependence of either crystallinity or stiffness on 1-pentene content is observed in these copolymers, associated with their capability of crystallizing in the trigonal form.

keywords

  • propylene-co-1-pentene copolymers; monoclinic form; mesomorphic entities; trigonal crystallites; stiffness; crystallinity