At present,the research related biomass materials has become a hot topic.The four-step foam forming mechanism which was made up of raw material blending stage,bubble nucleation stage,bubble growth stage and curing finalization stage was first put forward according to the foam forming problem of biomass materials.In the raw material blending stage,the phase transition mechanism and existence form of plant fiber was analyzed.In bubble nucleation stage,the homogeneous nucleation mechanism and influencing facto...