title: FT-IR and FT-Raman studies of cross-linking processes with Ca(2+) ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch--part I.
abstract: FT-IR and FT-Raman spectroscopic methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) applied as a binder for moulding sands. The cross-linking was performed by chemical methods by introducing cross-linking substances with Ca(2+) ions or glutaraldehyde and by physical way, applying the microwave radiation. It was found that Ca(2+) ions cause formation of cross-linking ionic bonds within carboxyl and carboxylate groups. Glutaraldehyde generates formation of cross-linking bonds with hemiacetal and acetal structures. Whereas in the microwave radiation field, due to dehydration, lattices are formed by anhydride bonds.
authors.affiliation: AGH University of Science and Technology, Faculty of Foundry Engineering, Reymonta 23, 30 059 Cracow, Poland. Electronic address: beata.grabowska@agh.edu.pl.
authors.forename: Beata
authors.initials: B
authors.lastname: Grabowska
authors.affiliation: AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Mickiewicza 30, 30-059 Cracow, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Sitarz
authors.affiliation: AGH University of Science and Technology, Faculty of Foundry Engineering, Reymonta 23, 30 059 Cracow, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Olejnik
authors.affiliation: AGH University of Science and Technology, Faculty of Foundry Engineering, Reymonta 23, 30 059 Cracow, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Kaczmarska
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000812:Anhydrides / Q000737:chemistry; D002118:Calcium / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004574:Electromagnetic Fields; D005976:Glutaral / Q000737:chemistry*; D007477:Ions; D008872:Microwaves; D012964:Sodium; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013213:Starch / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D000812:Anhydrides; D003432:Cross-Linking Reagents; D007477:Ions; C006903:carbopol 940; D013213:Starch; C034848:carboxymethyl starch; D012964:Sodium; D002118:Calcium; D005976:Glutaral
keywords: Cross-linking; Foundry; Glutaraldehyde; Microwave; Polymer composition; Spectroscopy