Functionalization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) films via surface-initiated atom transfer radical polymerization: Comparison with the conventional free-radical grafting procedure

• Published in: Journal of applied polymer science Vol. 120; no. 1; pp. 184 - 194
• Main Authors: Lao, Hoi-Kuan, Renard, Estelle, Fagui, Amani El, Langlois, Valérie, Vallée-Rehel, Karine, Linossier, Isabelle
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05.04.2011; Wiley; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Bacteriology; biocompatibility; biodegradable; Contact angle; Copolymerization; Density; Exact sciences and technology; Grafting; Initiators; Life Sciences; Materials science; Microbiology and Parasitology; Organic polymers; PHEMA; Physicochemistry of polymers; polyesters; Polymerization; Polymers; Preparation, kinetics, thermodynamics, mechanism and catalysts; Radicals; Reproduction; Biological properties; Surface reaction; biodegradable; Valerate(hydroxy) copolymer; Graft copolymer; biocompatibility; Atom transfer polymerization; Butyrate(hydroxy) copolymer; Hydroxyethyl methacrylate copolymer; Experimental study; Property processing relationship; Grafting; polyesters; Structure processing relationship; Ester copolymer; Wettability; Morphology; Surface properties
• ISSN: 0021-8995; 1097-4628; 1097-4628
• DOI: 10.1002/app.32967

We modified hydrophobic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) films with hydrophilic chains to control their surface properties. We designed and investigated surface-initiated atom transfer radical polymerization (SI-ATRP) to modify the PHBHV films by grafting poly(2-hydroxyethyl methacrylate) (PHEMA) from the surface. This method consisted of two steps. In the first step, amino functions were formed on the surface by aminolysis; this was followed by the immobilization of an atom transfer radical polymerization initiator, 2-bromoisobutyryl bromide. In the second step, the PHEMA chains were grafted to the substrate by a polymerization process initiated by the surface-bound initiator. The SI-ATRP technique was expected to favor a polymerization process with a controlled manner. The experimental results demonstrate that the grafting density was controlled by the reaction conditions in the first step. The grafted films were analyzed by Fourier transform infrared spectroscopy, contact angle testing, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The results show that grafted chains under the SI-ATRP method were preferentially located on the surface for surface grafting and in the bulk for conventional free-radical polymerization initiated by benzoyl peroxide.