9.3.1　Skin substitutes materials

Skin is the largest organ of the human body and is more vulnerable than any other part of the body.Injuries of skin can range from small wounds that heal spontaneously within a few days，to even large third-degree burns that threaten the lives of patients.In acute largearea wounds and burns，elderly and diabetic patients，the normal wound healing response and the skin's inherent tissue regeneration ability are far from enough.This is a challenge for skin repair.Biomedical polymer materials are natural and synthetic polymer biomaterials with special functions produced by the organic combination of medicine and polymer science.They can have different physical and chemical properties through the control of the composition and structure to meet different needs.They also have some advantages that they are easy to process and easy to disinfect and sterilize，and have good biocompatibility.It has been applied throughout the entire medical field，and now the biomedical polymer materials related to alternative materials for skin defect repair are summarized as follows.(https://www.daowen.com)