New epoxy–silica hybrid coatings were prepared by a dual process consisting of a sol–gel process using tetraethoxysilane (TEOS) or 3-glycidyloxypropyl trimethoxysilane (GPTMS) in the presence of hyperbranched poly(ethyleneimine) with ethoxysilyl groups at the chain ends (PEI-Si) followed by a homopolymerization of diglycidylether of bisphenol A (DGEBA) using 1-methylimidazole (1-MI) as anionic initiator. The influence of the amount of TEOS and GPTMS in the characteristics of the coating was examined. Thin transparent films were obtained and their morphology was observed by transmission electron microscopy (TEM). The hydrolytic condensation was confirmed by 29Si NMR studies. Cage-like nanometric structures were formed in case of adding GPTMS and bigger silica particles on adding TEOS to the formulation. Thermal stability was evaluated by thermo- gravimetry and the scratch resistance properties were also investigated, showing an improvement in resistance to break and to detachment in all the coatings containing GPTMS.
Hybrid epoxy networks from ethoxysilyl-modified hyperbranched poly(ethyleneimine) and inorganic reactive precursors / Acebo, Cristina; Fernández Francos, Xavier; Santos, José Ignacio; Messori, Massimo; Ramis, Xavier; Serra, Àngels. - In: EUROPEAN POLYMER JOURNAL. - ISSN 0014-3057. - STAMPA. - 70:(2015), pp. 18-27. [10.1016/j.eurpolymj.2015.06.029]
Hybrid epoxy networks from ethoxysilyl-modified hyperbranched poly(ethyleneimine) and inorganic reactive precursors
MESSORI, Massimo;
2015
Abstract
New epoxy–silica hybrid coatings were prepared by a dual process consisting of a sol–gel process using tetraethoxysilane (TEOS) or 3-glycidyloxypropyl trimethoxysilane (GPTMS) in the presence of hyperbranched poly(ethyleneimine) with ethoxysilyl groups at the chain ends (PEI-Si) followed by a homopolymerization of diglycidylether of bisphenol A (DGEBA) using 1-methylimidazole (1-MI) as anionic initiator. The influence of the amount of TEOS and GPTMS in the characteristics of the coating was examined. Thin transparent films were obtained and their morphology was observed by transmission electron microscopy (TEM). The hydrolytic condensation was confirmed by 29Si NMR studies. Cage-like nanometric structures were formed in case of adding GPTMS and bigger silica particles on adding TEOS to the formulation. Thermal stability was evaluated by thermo- gravimetry and the scratch resistance properties were also investigated, showing an improvement in resistance to break and to detachment in all the coatings containing GPTMS.
Pubblicazioni consigliate
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris
