Synthesis and characterization of hybrid films from hyperbranched polyester using a sol–gel process

Abstract

International audienceHybrid organic/inorganic materials were prepared by an in situ sol-gel process using tetraethoxysilane (TEOS) in the presence of hyperbranched polyester. The influences of hyperbranched polyester molar mass as well as the amount of TEOS were examined. The condensation degree was characterized by solid state 29Si NMR. The combination of solubility tests, calcination tests, SAXS and dynamic mechanical analysis allowed us to investigate the hybrid material nanostructure. The results show high compatibility between the inorganic silica phase and the organic polymer phase, due to the spherical shape of the hyperbranched polymer and its numerous hydroxyl groups. As a consequence, a continuous inorganic phase was formed even with a low silica precursor content without any macroscopic phase separation. These hybrid materials have a high Tg and high storage modulus even at an elevated temperature combined with improved thermal stability

Self‐assembled polymer nanocomposites and their networks

“…For acryP123 template synthesis, the resulting mesoporous silica surface area was 930 m 2 /g, again identical to that expected for SBA‐15 structures synthesized from the unfunctionalized P123. Average pore diameters and pore size distributions were measured via BJH N 2 adsorption/desorption isotherm experiments and were essentially identical for P123, aP123 , and acryP123 ‐templated silicas (Figure and Table ). Adsorption–desorption isotherms of dried and calcined aP123/acryP123 SBA material show Type IV hysteresis typical of mesoporous silica and similar to SBA‐15 .…”

“…In a sol-gel process, the inorganic phase such as silica can be homogenously distributed in the polymer matrix from sol-gel reactions of tetraalkoxysilanes in the presence of reactive monomers or macromers. 18,[22][23][24][25][26][27] Here, we detail the end-group functionalization of the Pluronic V R -based copolymers to attach either one or two reactive end groups, which in this case are either allyl-or acrylate-based as shown in Scheme 1. Allyl and acrylate reactive groups were selected because the vinyl groups in either case can be polymerized via free radical mechanism.…”

Improved epoxy thermosets by the use of poly(ethyleneimine) derivatives

“…As has been mentioned before, HBPs are advantageous modifiers to enhance the properties of epoxy thermosets. Taking all of this into account, some authors combined the strategy of the generation of silica particles by the sol-gel procedure with the use of hyperbranched structures to improve some characteristics of thermosetting materials [66,201,202].…”

Epoxy Sol-Gel Hybrid Thermosets

“…Hydrolysis is a reversible process in which there is the possibility that alcohol attacks the silanol leading to the formation of an alkoxide. This process is known as re-esterification and is favored at high content of alcohol as the solvent or in the presence of other hydroxylic species [26,27].…”