eur op eanexhibitionofcreati vityandinnovation - Europe Direct Iasi

EUROINVENT 2013
“Petru Poni” Institute of Macromolecular Chemistry, Iasi
37.1.
Title EN
Authors
Institution
Description
EN
Class no.
New Partially Aliphatic Copolyimides Films Modified by
Plasma Treatment for High Performance Applications
Dumitru Popovici (1) , Irina Andreea Barzic (1) , Maria
Butnaru (2) , Iuliana Stoica (1) , Camelia Hulubei (1) , Ghiocel
Emil Ioanid (1) , Stelian Vlad (1)
(1)
“Petru Poni” Institute of Macromolecular Chemistry,
Iasi
(2)
“Gr. T. Popa” University of Medicine and Pharmacy,
Iasi
Polyimides are characterized by some outstanding properties, such
as superior thermal and chemical resistant, excellent mechanical
strength and good adhesion to surfaces. As a result, they have been
extensively used in aerospace, microelectronics, optoelectronics,
composites and membranes. Also, polyimides have been proved to be
biocompatible, with applications in biomedical fields as substrate/
encapsulation materials in bio-micro-electromechanical-systems
(Bio-MEMS) or as micro-structured substrates for contact guidance
of osteoblast cell growth.
Novel copolyimides based on 3,3’,4,4’-benzophenontetracarboxylic
dianhydrides, 4,4’-diaminodiphenylmetane and 1,6-diaminohexane
were synthesized and their corresponding films were obtained. By
cold plasma treatment the films surfaces wettability has been
improved. Polar component contribution to surface tension have been
enhanced from 10 to 50%, increasing the surface hydropho-bicity
characteristics and decreasing interfacial tension with blood in the
range of 2.07–2.95 mN/m, in accord with the biocompatibi-lity
criteria. The results have reflected the capacity of aliphatic moieties
to lower the electron-donor character of polar contribution to surface
tension, while maintaining a small adhesion of polymer films to red
blood cells and a proper cohesion to platelets, albumin, fibrinogen
and immunoglobulin. By increasing aliphatic content in polyimides
chains, the rejection of platelets has been increased, prohibiting
thrombosis and favoring cohesion with plasma proteins.
Atomic force microscopy data have revealed a uniform and flat
surface morphology for untreated samples (Sq = 0.31–0.48 nm),
changing into a granular structure after plasma treatment with
surfaces roughness Sq < 8 nm for all polyimides films, being
favorable for laminar blood flow, preventing poststenotic turbu-lence
and clot formation.
Acknowledgements. This work is financially supported from PN-II-
ID-PCE-2011-3-0937, Project No. 302 / 5.10.2011, Stage 2013
Innovative Researches
NATIONAL
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