Encapsulation methods for photo-polymerisable self-healing formulations.
The aim of this work is to encapsulate a self-healing photo-polymerisable material for aerospace applications. To meet the technical requirements of space applications - low and high temperatures: -120 °C (dark side) to +250 °C (solar side); UV radiations: 200-400 nm; low pressure: 10(-4 )Pa - we chose trimethylolpropane triacrylate as healing agent. This monomer polymerises at 190 °C. To avoid its earlier thermal polymerisation, an inhibitor was added to the monomer/photo-initiator formulation. Moreover, among several microencapsulation techniques tested, we chose the sol-gel process to form silica microcapsules containing the self-healing formulation. These microcapsules were characterised by different analysis (scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), Fourier transform infra-red spectroscopy (FTIR), etc.) and satisfied our requirements (size 1-30 μm, thermal stability >250 °C). After the microcapsules breakage, the generation of poly(TMPTA) film by radical photopolymerisation of the released TMPTA monomer was proved by disappearance of the IR peak at 1635 cm(-1) (assigned to TMPTA). The obtained film has a thermal stability above 300 °C.
a Macromolecular Chemistry Laboratory , Paul Cezanne University (Aix-Marseille III) , Marseille , France ;|b Department of Research and Development , Catalyse Company , Marseille , France ;
Wael
W
Ballout
a Macromolecular Chemistry Laboratory , Paul Cezanne University (Aix-Marseille III) , Marseille , France ;|b Department of Research and Development , Catalyse Company , Marseille , France ;
Alain
A
Périchaud
a Macromolecular Chemistry Laboratory , Paul Cezanne University (Aix-Marseille III) , Marseille , France ;|b Department of Research and Development , Catalyse Company , Marseille , France ;
Laura
L
Caserta
b Department of Research and Development , Catalyse Company , Marseille , France ;
Mickael
M
Devassine
c Department of Polymer National Research & Development Institute for Chemistry and Petrochemistry , Bucharest , Romania ;
Cristina Lavinia
CL
Nistor
d Institute of Chemical Sciences & Kazakh-British Technical University , Almaty , Kazakhstan.
Rinat
R
Iskakov
D000179:Acrylates / Q000737:chemistry*; D002214:Capsules / Q000737:chemistry; D055668:Photochemical Processes; D014466:Ultraviolet Rays
D000179:Acrylates; D002214:Capsules; C027993:trimethylolpropane triacrylate
microencapsulation; photopolymerisation; self-healing; sol–gel