Type I erosion

In general terms. Type I erosion encompasses water-soluble polymers that have been insolubilized by hydrolytically unstable crosslinks. Type II erosion includes polymers that are initially water-insoluble and are solubilized by hydrolysis, ionization, or protonation of a pendant group. Type III erosion includes hydrophobic polymers that are converted to small water-soluble molecules by backbone cleavage. 

The most widely used polymer system that bioerodes by Type I erosion or by a combination of Type I and Type III erosion is gelatin that has been insolubilized by heat treatment, aldehyde treatment, or chromic acid treatment. 

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