Professor, Ingénierie des Matériaux Polymères, CNRS UMR 5223, Université de Lyon, France

Dr. Emmanuel Beyou obtained his PhD degree from the University of Bordeaux, France, in 1994, with research activities focusing on the synthesis of new fluorinated polysiloxanes exhibiting hydrophobic properties. Then, he carried out his postdoctoral research at the Charles Sadron Institute, Strasbourg, France, and he is presently Professor at the University of Lyon. His current research activities are located in the CNRS joint research unit "engineering of polymeric materials" and they are guided by the synthesis of both model macromolecular systems with controlled properties and nanocomposites. In particular, he has developed “graft-from” polymerization procedures onto fillers with different form factor in order to control their dispersion state in a polymer matrix. He is author of 55 papers in peer-reviewed international journals, 3 chapters of scientific books and serves as reviewer for numerous scientific journals and is expert for both national and international agencies.

Speech Title: Acyloxyimide Derivatives as Peroxides Alternatives for the Melt functionalization of Polyethylene and polyamide-11 with maleic anhydride and diethyl maleate

Aims: Acyloxyimides as new H-abstracting agent have been developed for the melt radical grafting of maleic anhydride (MA) onto polyethylene and polyamide-11. The reaction was conducted in the temperature range 190 - 250 °C in a mini-extruder and the hydrogen abstraction ability of these acyloxyimides was demonstrated.

Methods: In a typical process, 5 g of LDPE, MA (4 wt% or 2 wt%) and acyloxyimides (0.35-0.87 wt%) or L101-based peroxide (0.18 wt%) were added in the preheated mini-extruder (Thermo Scientific HAAKE™ MiniCTW micro-conical twin screw compounder, 7 ml) simultaneously at a rotor speed of 60 rpm and a temperature of 110°C.

Results: Optimal experimental conditions were defined by varying the initial MA content and the degree of grafting of MA was determined by infra-red spectroscopy for PE and 1H NMR for PA-11. For exemple, the MA grafting degree was as high as 2.98 wt% when using tBu-NAP as H-abstracting agent at 230°C with only a slight modification of the PE chains structures as proved by rheological experiments while the use of a peroxide (L101) lead to a lower grafting degree (1.9 wt%) and a cross-linking of the polymer chains confirmed by the three – five fold higher complex viscosity.

Conclusions: These results showed the interest of these new structures to modify polyolefins by melt extrusion with little change of their rheological properties. The extension of these results to others commodities polymers will be reported in future.