Linear Melt Rheology of Pom-Pom Polystyrenes with Unentangled Branches

详细信息    查看全文

• 作者：Evelyne van Ruymbeke ; Michael Kapnistos ; Dimitris Vlassopoulos ; Tianzi Huang ; Daniel M. Knauss
• 刊名：Macromolecules
• 出版年：2007
• 出版时间：March 6, 2007
• 年：2007
• 卷：40
• 期：5
• 页码：1713 - 1719
• 全文大小：165K
• 年卷期：v.40,no.5(March 6, 2007)
• ISSN：1520-5835

文摘

We measured the linear viscoelastic properties of a series of polystyrene melts with pom-pomarchitecture consisting of backbones ranging from marginally to well-entangled (of molecular weight M_b), end-grafted with q unentangled branches (M_br) per backbone end. In this case, the branches relax very fast and actprimarily as solvents for the backbone. Using a time-marching tube-based model, we showed that, in such a caseonly, the pom-pom polymer is equivalent to a blend of long (M_L mages/entities/ap.gif"> M_b + 2M_br) and short (M_S mages/entities/ap.gif"> M_br) linearchains with respective proportion (M_b + 2M_br)/2(q - 1)M_br.