ma9b02023_si_001.pdf (388.05 kB)
Direct High-Temperature Form I Crystallization of Isotactic Poly(1-butene) Assisted by Oriented Isotactic Polypropylene
journal contribution
posted on 2019-12-08, 20:29 authored by Zhixin Guo, Rui Xin, Jian Hu, Yunpeng Li, Xiaoli Sun, Shouke YanThe crystallization behavior of isotactic poly(1-butene)
(iPBu)
from melt on the surface of melt-drawn oriented isotactic polypropylene
(iPP) thin films and in the melt-drawn oriented iPBu/iPP blend thin
films was studied. It has been found that iPBu in the melt-drawn iPBu/iPP
blend films is form I crystals like in the melt-drawn thin films on
its own. The form I iPBu crystals exhibit, however, an oriented edge-on
lamellar structure rather than the fibrils or shish crystals observed
in melt-drawn pure iPBu films, reflecting the influence of iPP on
the melt-draw behavior of iPBu. Melt recrystallization of iPBu in
the iPBu/iPP melt-drawn films does not change its orientation status
and crystalline modification, reflecting the epitaxial capability
of iPBu on oriented iPP. This has been further confirmed by oriented
form I crystallization of the spin-coated iPBu thin films from melt
on oriented iPP melt-drawn films, which eliminates the confinement
effect on the form I iPBu crystallization in the melt-drawn iPBu/iPP
film. In situ IR study also confirms that the high melting temperature
form I iPBu crystals are directly formed on the iPP substrate. The
IR results further demonstrated that the crystallization of form I
iPBu at 104 °C on iPP substrate is faster than its form II. Taking
all of the experimental results into account, the epitaxial crystallization
of iPBu on oriented iPP substrate in its form I is believed to be
the synergistic effect of lattice matching between iPP and form I
iPBu as well as the crystallization kinetics of iPBu.