The development of advanced materials from bio-renewable protein biopolymers requires the generation of more exogenous bonds to maintain the microstructure and durability in the final products. Casein is the main protein of milk, representing about 80% of the total protein. In the present investigation the casein protein was solubilized and/or emulsified in aqueous alkaline solutions, and 2D films and 3D matrices were produced. The effects of silane (3-aminopropyl triethoxy silane), DL-glyceraldehyde and glutaraldehyde on tensile properties and water swelling/absorption of 2D casein films and also the microstructure of the freeze-dried 3D matrices were analyzed. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that there were no significant changes in the molecular weight (19-23.9 kDa) of the casein proteins on exposure to alkaline solutions of sodium hydroxide and silane. The casein films produced without glycerol plasticizer and with heat treatment (130 °C for 18 h) were fragile. However, the fragile films were transformed into ductile and tough materials on exposure to moisture (i.e., conditioned for one week at 50 ( 2% relative humidity and 22 ( 2 °C) and showed a maximum average tensile strength of 49-52 MPa and modulus of 1107-1391 MPa. The chemical crosslinkers (i.e., DL-glyceraldehyde and glutaraldehyde) improved the microstructure of glycerol plasticized casein protein, when analyzed under scanning electron microscope (SEM). Furthermore, these chemical cross-linking agents enhanced the mechanical properties and water resistant properties of casein films.
The development of advanced materials from bio-renewable protein biopolymers requires the generation of more exogenous bonds to maintain the microstructure and durability in the final products. Casein is the main protein of milk, representing about 80% of the total protein. In the present investigation the casein protein was solubilized and/or emulsified in aqueous alkaline solutions, and 2D films and 3D matrices were produced. The effects of silane (3-aminopropyl triethoxy silane), DL-glyceraldehyde and glutaraldehyde on tensile properties and water swelling/absorption of 2D casein films and also the microstructure of the freeze-dried 3D matrices were analyzed. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that there were no significant changes in the molecular weight (19-23.9 kDa) of the casein proteins on exposure to alkaline solutions of sodium hydroxide and silane. The casein films produced without glycerol plasticizer and with heat treatment (130 °C for 18 h) were fragile. However, the fragile films were transformed into ductile and tough materials on exposure to moisture (i.e., conditioned for one week at 50 ( 2% relative humidity and 22 ( 2 °C) and showed a maximum average tensile strength of 49-52 MPa and modulus of 1107-1391 MPa. The chemical crosslinkers (i.e., DL-glyceraldehyde and glutaraldehyde) improved the microstructure of glycerol plasticized casein protein, when analyzed under scanning electron microscope (SEM). Furthermore, these chemical cross-linking agents enhanced the mechanical properties and water resistant properties of casein films.
การแปล กรุณารอสักครู่..