Study on the Rheological Behavior for Polymer Melts and Concentrated Solutions The Molecular Theory of Visco-elasticity for Recoverable Strain and Swelling Ratio of Homo-polymers Melts Extrudate是什么意思 Study on the Rheological Behavior for Polymer Melts and Concentrated Solutions The Molecular Theory of Visco-elasticity for Recoverable Strain and Swelling Ratio of Homo-polymers Melts Extrudate怎么读