| 摘要 |
PURPOSE: A straw for checking deterioration is provided to prevent a user from taking deteriorated drinks by reducing or blocking the inlet of the straw. CONSTITUTION: A straw for checking deterioration is made of a pH-sensitive polymer or comprises a straw main body (110) and an extension unit (120) made of the pH-sensitive polymer. The pH-sensitive polymer can be contracted or expanded according to the pH of liquid. The pH-sensitive polymer is collected as a basic polymer. The basic polymer is selected from chitosan, polylysine, polyethyleneimine, diethylaminoethyl dextran, and polyamidoamine dendrimer. |
