摘要 : <abstract xmlns="http://www.wiley.com/namespaces/wiley" type="main"> <p> A new Monte Carlo simulation method is proposed for the step polymerization of AB ₂ ‐type monomer conducted in ... 展开 <abstract xmlns="http://www.wiley.com/namespaces/wiley" type="main"> <p> A new Monte Carlo simulation method is proposed for the step polymerization of AB ₂ ‐type monomer conducted in a continuous flow stirred‐tank reactor (CSTR). The effect of the second B group reactivity, represented by the reactivity ratio <i>r</i> is investigated. The degree of branching (DB) at large degree of polymerization ( <i>P</i> ) limit, DB <i> _P </i> _→∞ does not change with the mean residence time <mat:math xmlns:mat="http://www.w3.org/1998/Math/MathML" display="inline" altimg="urn:x-wiley:dummy:media:mats201700020:mats201700020-math-0001" xmlns:wiley="http://www.wiley.com/namespaces/wiley/wiley" wiley:location="equation/mats201700020-math-0001.png"> <mat:mover accent="true"> <mat:mi>t</mat:mi> <mat:mo>ˉ</mat:mo> </mat:mover> </mat:math> . The value of DB <i> _P </i> _→∞ becomes larger by increasing <i>r</i> and is larger than the corresponding batch polymerization. The weight fraction distribution at high molecular weight tail follows a power law <mat:math xmlns:mat="http://www.w3.org/1998/Math/MathML" display="inline" altimg="urn:x-wiley:dummy:media:mats201700020:mats201700020-math-0002" xmlns:wiley="http://www.wiley.com/namespaces/wiley/wiley" wiley:location="equation/mats201700020-math-0002.png"> <mat:mrow> <mat:mi>W</mat:mi> <mat:mo stretchy="false">(</mat:mo> <mat:mi>P</mat:mi> <mat:mo stretchy="false">)</mat:mo> <mat:mo>∝</mat:mo> <mat:msup> <mat:mi>P</mat:mi> <mat:mrow> <mat:mo>?</mat:mo> <mat:mi>α</mat:mi> </mat:mrow> </mat:msup> </mat:mrow> </mat:math> , and a simple formula to predict the power exponent α is proposed. The relationship between the radius of gyration 〈 <i>s</i> ² 〉 ₀ and <i>P</i> does not change with <mat:math xmlns:mat="http://www.w3.org/1998/Math/MathML" display="inline" altimg="urn:x-wiley:dummy:media:mats201700020:mats201700020-math-0003" xmlns:wiley="http://www.wiley.com/namespaces/wiley/wiley" wiley:location="equation/mats201700020-math-0003.png"> <mat:mover accent="true"> <mat:mi>t</mat:mi> <mat:mo>ˉ</mat:mo> </mat:mover> </mat:math> , and large polymers obtained in a CSTR are much more compact than those formed in batch polymerization. CSTR is advantageous to synthesize compact HB polymers, especially with a smaller <i>r</i> ‐value. </p> </abstract> 收起