Modified tapioca starch as a rheology modifier in acrylic dispersion system

作者：Makmoon Thidarat; Foungfuchat Asira; Jiratumnukul Nantana^*

来源：Progress in Organic Coatings, 2013, 76(6): 959-962.

DOI：10.1016/j.porgcoat.2012.10.021

• Rheology modifier
• Tapioca starch
• Water based coating

Tapioca starch was modified by esterification reaction using octenylsuccinic anhydride (OSA) to use as a rheological modifier. Effect of degree of substitution (DS = 0.01-0.04) of octenyl side chain on rheological properties of modified starch in acrylic dispersion system (ASD) was investigated. At low starch to dry acrylic ratio (0.2:100), shear viscosity at low shear rate of OSA-starch containing ASD system increased when the DS of OSA-starch increased. Thickening ability and thixotropic behavior of modified starches in acrylic dispersion system were studied at various modified starches to dry acrylic ratios (0.1-4:100). The results showed that modified starches provided good thickening efficiency. Moreover, an optimum concentration of modified starches, giving the highest thickening efficiency decreased as the DS increased. Results of rheological behavior illustrated that associative networks were formed by hydrophobic interaction between octenyl side chains and acrylic particles in acrylic dispersion system. The rheological properties of modified starches prepared in this study showed a potential in using as an associative thickener in water-based coating system.

• 出版日期2013-6