Development of new stimuli responsive thin films on polymeric substrates by using different dry processes


CALL: 2012

DOMAIN: MS - New Functional and Intelligent Materials and Surfaces

FIRST NAME: Maryline





KEYWORDS: stimuli responsive, thin films, plasma polymers, surface characterization

START: 2013-01-01



Submitted Abstract

The THERMOFILM project aims at developing new stimuli responsive thin films on polymeric substrates by using two different dry processes, namely, a low pressure plasma and an initiated chemical vapour deposition (iCVD) process.Stimuli-responsive polymers (SRPs) are materials composed of polymers that respond in a drastic way to a very slight change in temperature, pH, electric, or magnetics fields or other external stimuli. Surfaces coated with a thermally responsive polymer (TRP) present switchable hydrophilic-hydrophobic properties allowing to control important interfacial phenomena such as wetting, fluid flow and adhesion. The integration of such films on devices will lead to interesting applications such as nano/microlitre fluid handling, protein separation, separation and purification of metal ions and biomolecules, water purification, cell or tissue culture on dishes with an attachment-detachment control by simple temperature change.According to the literature, TRPs have been mainly synthesized by wet chemical processes and attention was essentially focused on TRPs exhibiting a lower critical solution temperature (LCST). Below its LCST, the polymer is soluble in water and it exists in a random “coil configuration”. Above its LCST, the polymer chains undergo a sharp change in hydrophobicity and collapse into a “globular” conformation. As an environmentally friendly and easily up-scalable technique, the dry technologies appear as an alternative way to achieve the sustainable synthesis and production of these TRP films on various substrates. In the framework of the THERMOFILM project, these new functional surfaces will be synthesized by using a low pressure plasma process. By working with a pulsed electrical excitation, free radical polymerisation reaction will be promoted, allowing the retention of the chemical and structural vinyl-based monomer, as it is now well established, that these last conditions must be fulfilled to successfully elaborate TRP films. Investigations for tuning the lower critical solution temperature (LCST) value will be performed by promoting plasma copolymerization reactions. To the best of our knowledge, up to now, no published work has been reported on the elaboration by plasma of these new smart surfaces presenting a highly controlled LCST value. Moreover, by combining plasma process and exhaustive layer surface characterisations, the project will allow a better understanding and predicting of plasma polymerization mechanisms. The benefits of such knowledge will then be exploited for the elaboration of other new functional plasma polymer thin films.As a complementary technique to the plasma technology and starting from the same selected vinyl-based monomers, an initiated chemical vapour deposition (iCVD) process will also be employed for the synthesis of TRP coatings. Indeed, there is recently a growing interest for this technique based on the effective use of an initiator agent allowing a good control of the polymer chemistry. This promising process, presently not yet developed in Luxembourg, allows to synthesize coatings presenting various properties such as hydrophobicity, hydrophilicity, ambiphilicity and pH sensitivity.At the end of the project, it will be possible to compare the final properties of the TRP coatings obtained by both plasma CVD and iCVD techniques and have a clear overview of the advantages and/or drawbacks of each process.The research work will promote the collaboration with the University of Bari, in particular with an internationally recognized plasma research team, headed by the Professor d’ Agostino. Hence, Dr Moreno, a researcher from the SAM department of the CRP-Gabriel Lippmann, will have the opportunity to complete her knowledge on plasma polymer films. Moreover, she will be trained on coating depositions by the iCVD technique.

This site uses cookies. By continuing to use this site, you agree to the use of cookies for analytics purposes. Find out more in our Privacy Statement