Phase behavior of a substituted poly(paraphenylene): Poly(para-2,5-didecyl-p-phenylene)

摘要: The thermal behavior of poly(para-2,5-didecyl-p-phenylene) has been in- vestigated by differential scanning calorimetry and real time X-ray diffraction. Poly(para-2,5-didecyl-p-phenylene) is a semicrystalline material that crystallizes in layered structure. system exhibits two transitions the investigated temperature range. first one, occurring at lower temperatures, provokes reduction spacing accompanied an appreciable disordering lateral side chains. Above transition shearable, highly viscous, birefrin- gent. Thus, we have associated this to formation mesophase. higher twofold endothermic DSC peak characterized disappearance diffracted intensity. At temperatures above second presents characteristics isotropic melt. Conse- quently, with complete poly- meric backbones. By following appropriate treatment it shown shape endotherm characterizing transi- tion can be changed into single endotherm. This effect interpreted as being due kinetics main-chain ordering. ordering seems proceed initial growth domains high level order followed subsequent increase these through inclusion less ordered material. q 1998 John Wiley & Sons, Inc. J Polym Sci B: Phys 36: 49-54,