Disturbance of Atactic Polystyrene Networks on the Polymorphism Transitions of Syndiotactic Polystyrene: not favorable to β form
Disturbance of atactic polystyrene (aPS) networks on the polymorphism transitions ofsyndiotactic polystyrene (sPS) was studied by using in-situ wide angle X-ray diffraction (WAXD) anddifferential scanning calorimetry (DSC). Two series samples of solvent induced sPS crystals in aPSnetworks were prepared, one formed in aPS gel (sPS/aPSNW1) and the other formed in aPS solutionand thereafter fixed by cross-linked aPS chains (sPS/aPSNW2). For comparison, SPS blends with linearaPS (sPS/aPS) were also prepared under the same conditions. The sPS clathrate (δ ) form crystal wasobtained in all samples. The δ form of sPS transforms into γ form and then into α form with a lowerheating rate, while the δ form of sPS transforms directly into β form with a higher heating rate. But, thepresence of aPS networks was not favorable for the formation of β form of sPS. When annealed the sPSδ form samples at a temperature above 150°C, aPS networks in both sPS/aPSNW2 and sPS/aPSNW1retard the transformation of dform into β form, but improve the transition of dform into γ form and then into α form. Moreover, aPS networks were also not favorable for the formation of β form of sPSfrom melt-crystallization, but for α form. It shows that the presence of aPS networks disturbs the sPSmodifications and is not favorable to the formation of sPS β form during polymorphism transitions.
syndiotactic polystyrene clathrate crystal crystalline transition atactic polystyrene networks
Xia Gao Ruigang Liu Oleksiy starykov Wilhelm Oppermann
Beijing Centre of Physical and Chemical Analysis, Beijing Academy of Sciences and Technology,Beijing Institute of Physical Chemistry, Clausthal University of Technology, Arnold-Sommerfeld Strasse 4,386
国内会议
哈尔滨
英文
1-30
2011-08-22（万方平台首次上网日期，不代表论文的发表时间）