کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5191684 1381237 2005 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synthesis and characterization of (star polystyrene)-block-(polyisoprene)-block-(star polystyrene) copolymers
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Synthesis and characterization of (star polystyrene)-block-(polyisoprene)-block-(star polystyrene) copolymers
چکیده انگلیسی
A (star polystyrene)-block-(linear polyisoprene)-block-(star polystyrene) copolymer, (S)nI(S)n, was prepared. The star polystyrene was produced via anionic polymerization of polystyrene macromonomers each containing an unsaturated double bond (vinyl) at the chain end. This vinyl-terminated polystyrene macromonomer (SSTM) was obtained beforehand via the synthesis of a living polystyrene using alkyllithium and the termination with p-chloromethylstyrene (PCMS). The living site in the core of the star polystyrene enabled the construction of the succeeding polyisoprene block resulting in the living (star polystyrene)-block-(linear polyisoprene) copolymer, (S)nI. This living diblock copolymer was then coupled with 1,2-dibromoethane (DBE) to form the well-defined (S)nI(S)n. Compared to a linear polystyrene-block-polyisoprene-block-polystyrene, SIS, with the same molecular weight, (S)nI(S)n had a higher Tg and exhibited a lamellae-forming phase separation in conjunction with many dislocation defects. The thermal stability appeared independent of the molecular structure, and the radius of gyration and viscosity of (S)nI(S)n were much smaller than SIS.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 46, Issue 8, 29 March 2005, Pages 2558-2566
نویسندگان
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