PVA (Mw 125000, 98-99% hydrolyzed, ～2800 polymerization) is polyvinyl alcohol with a molecular weight of 125000 and has hydrolytic properties. The degree of hydrolysis refers to the conversion percentage of acetyl groups in the original polyvinyl acetate to hydroxyl groups. PVA of this specification is derived from the hydrolysis of polyvinyl acetate after polymerization, removing acetyl groups to yield polyvinyl alcohol. PVA with varying degrees of hydrolysis can be used in self-crosslinking formulations to create freeze gels, which serve as biological excipients.