title: Synthesis and solution behavior of poly(ε-caprolactone) grafted hydroxyethyl cellulose copolymers.
abstract: Trimethylsilylated hydroxyethyl cellulose (TMSHEC) was synthesized by using hexamethyldisilazane (HMDS) as silylated agent. With the partial protection of hydroxyl groups of HEC by silylation, the novel poly(ɛ-polycaprolactone) (PCL) grafted HEC (HEC-g-PCL) copolymers were successfully prepared by homogenous ring-opening graft polymerization and deprotection procedure. The structure of HEC-g-PCL copolymers was characterized by FTIR and 1H NMR. Fluorescence spectrum of HEC-g-PCL copolymer dilute solution indicated that copolymers could associate and form hydrophobic microdomains in aqueous solution. With the increasing of grafted PCL content, the critical association concentration (cac) of HEC-g-PCL copolymers decreased. The surface tension of HEC-g-PCL copolymers decreased dramatically with the increasing of the concentration and then approached to a plateau value when concentration was above the cac of HEC-g-PCL copolymers. The hydrodynamic radius of the aggregate of copolymer in dilute solution was found to increase with the increasing of the grafted PCL content. When the concentration of copolymer was above the cac, the zero-shear viscosity of the copolymer increased sharply and became much higher than that of HEC at the same concentration.
authors.affiliation: School of Chemical and Material Engineering, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China.
authors.forename: Chao
authors.initials: C
authors.lastname: Jiang
authors.forename: Xinling
authors.initials: X
authors.lastname: Wang
authors.forename: Peidong
authors.initials: P
authors.lastname: Sun
authors.forename: Cheng
authors.initials: C
authors.lastname: Yang
mesh_terms: D002482:Cellulose / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D057446:Hydrodynamics; D009682:Magnetic Resonance Spectroscopy; D011091:Polyesters / Q000138:chemical synthesis* / Q000737:chemistry; D058105:Polymerization; D012996:Solutions; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014783:Viscosity
chemical_list: D011091:Polyesters; D012996:Solutions; C016240:polycaprolactone; D002482:Cellulose; C002283:hydroxyethylcellulose