Solid Polymeric Electrolytes Obtained From Sulfated and Grafted Starch
Douglas C. Dragunski and Agnieszka Pawlicka
Solid polymeric electrolytes were obtained from sulfated and grafted with polyether amylopectin-rich starch. The FTIR spectra of the samples showed the characteristic S–O band at 1242 cm-1, indicating sulfated product, and also a small urethane band at 1735 cm-1, evidencing the occurrence of graftization reaction on the sulfated starch. TGA analysis evidenced the loss of hydrophilic properties of the sulfated and grafted samples and increase in their degradation temperature. The glass transition temperature (Tg) of the samples decreases also from 50°C to –60°C. The ionic conductivity of the samples was 2.77 ° x 10-6 S/cm at 85°C. All these results indicate that sulfatation and graftization reactions were successful, whereas the low Tg of the samples suggests that sulfated and grafted with polyethers starch is a good candidate to obtain solid polymeric electrolytes.