Biodegradable polyurethane and polyurethane ureas

A tissue engineering scaffold comprising a cured polyurethane or polyurethane/urea,

• wherein said polyurethane or polyurethane/urea comprises the reaction product of isocyanate, polyol, a chain extender having a hydrolysable linking group and, optionally, a conventional chain extender,
• said polyol having a molecular weight of 120 to less than 400,
• said chain extender having a hydrolysable linking group selected from the group consisting of diols and dithiols,
• the acid number of the polyurethane or polyurethane/urea is about zero, and
• the tissue engineering scaffold is biocompatible and biodegradable,
• wherein the polyurethane or polyurethane/urea comprises hard and soft segments and the amount of hard segment is 20 to 70% by weight based on the total weight of the polyurethane or polyurethane/urea;
• and
• wherein the soft segment comprises said polyol.