Studies on the crystalline intercalate formed by poly(ethylene oxide) and two different kinds of guest molecules

Abstract

The intercalate with poly(ethylene oxide) as the host compound and dichlorobenzene/dibromobenzene as the guest compounds (PEO-PDCL/PDBB) was studied by the aid of DSC, WAXD, and 13 C CP/MAS NMR. No selectivity was observed during the intercalating process of poly(ethylene oxide) (PEO) with pdichlorobenzene (PDCL) and p-dibromobenzene (PDBB). The orientated PDCL and PDBB molecules are randomly distributed in the benzenic layers between PEO sheets. With increasing PDBB molar fraction, the melting point of the intercalate rises up. WAXD results indicate that the size of orthorhombic crystal cells of PEO-PDCL/PDBB intercalates enlarges as PDBB molar fraction increases. Thereby, It is possible to control the size of crystal cell via adjusting PDBB content in the PEO-PDCL/PDBB intercalates. The 13 C CP/MAS NMR experiments imply that the carbons of PEO chains in the PEO-PDCL/PDBB intercalate are in the same chemical environment. This again supports that neither PDCL nor PDBB has priority in interacting with PEO.