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Crystallization Behavior of Model Branched Polyethylenes Rufina G. Alamo (FAMU-FSU College of Eng.) DMR-0503876.
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Crystallization Behavior of Model Branched PolyethylenesRufina G. Alamo (FAMU-FSU College of Eng.)DMR-0503876 Polyethyelenes are among the most important large volume polyolefins produced in the world. Their properties depend on the details of the crystalline structure acquired during crystallization. Studies with model branched polyethylenes containing F, Cl, Br, O or CH3 on each 19th carbon along the polymer backbone served to quantify the degree to which the orthorhombic lattice of the linear PE chain can tolerate atomic hydrogen substitution. The figures illustrate changes in crystallographic packing and drastic depression of melting with increasing van der Waals radius of the side branch accommodated in the crystal lattice (Macromolecules, 2006 in press). The packing behavior of these model polyethylenes sets the bases to describe unusual crystallographic patterns observed in other highly branched polyolefins. v d W (Å) 1.2 O 1.52 F 1.47 Cl CH3 Br 1.75 1.85
Crystallization Behavior of Model Branched PolyethylenesRufina G. Alamo (FAMU-FSU College of Eng.)DMR-0503876 Outreach: Freshman FSU Honors Chemistry students have been integrated in our research activities for one semester as part of their laboratory requirements. General lectures in polymers are given in the Fall semester to freshman and junior FSU female students who participate in WINSE (Women in Science and Engineering), a university program which focuses on the retention of women in science and engineering. The picture below shows PI and current graduate and undergraduate students. Education: One PhD student and one MS student graduated during the first year of the award. One post-doctoral scientist and a visiting scholar have been trained and presently two REU undergraduate students carry out research in polymer science under this award. Currently, two PhD students, A. Ghosal (3rd year), M. Vadlamuri (1st year), two MS students, Y. Chiary (2nd year) and L. Katam (2nd year) and one postdoctoral associate (K. Jeon) are doing work related to crystallization of polyolefins.