3.3.2　Design of biomedical polymers

Differing from the general polymer materials，biomedical polymer materials will directly contact and interact with the living organisms.In addition to the aforementioned physical and chemical performance requirements of general materials，special performance demanding in biomedical fields must also be fulfilled.Therefore，the design scheme of biomedical polymer materials needs to be comprehensively considered in terms of raw material selection，synthesis strategy，material structure and physical morphology.At the same time，the goal of biomedical polymer synthesis is to bring new functions（e.g.，intelligence，targeting，responsiveness，and visualization），and to optimize material properties（e.g.，biocompatibility，hydrophilicity and hydrophobicity，and mechanical properties）.At present，the design methods of biomedical polymers mainly include the synthesis of new biomedical polymers，and the modification of traditional polymers.Whether it is for the design and synthesis of new biomedical polymers，or for the modification and improvement of traditional polymers，the structure and composition of existing materials can be enriched，the vacancy of existing materials can be filled，and the biomedical polymer materials with new properties and special functions can be obtained.

To prepare biomedical polymers，the common design and synthesis methods mainly include polymerization，organic synthesis and physical blending.In recent years，benefiting from the rapid development of“living”controllable polymerization technology，a series of biomedical polymers prepared by functional monomers through polymerization have been successively designed and developed，and some of them have been clinically applied in the biomedical field.Meanwhile，the efficient organic synthesis reaction such as click-chemistry also provides sufficient possibility and conditions for the modification of biomedical polymers.In addition to polymerization，organic synthesis and other chemical methods，physical blending is also one of the effective strategies to obtain new medical polymer materials.(https://www.daowen.com)