PET is a semicrystalline thermoplastic polyester used in many fields. For a variety of applications, however, it is necessary to impart desired properties by introducing specific functional groups on the surface. Aminolysis of PET fibers with diamines (1,2-diaminoethane, 1,6-diaminohexane, 3,6-dioxa-1,8-diaminooctane, and 4,9-dioxa-1,12-diaminododecane) gives amino functional groups on the surface. The effects of temperature, reaction time, diamine concentration, and solvent employed for the grafting were studied. The graft yield was observed to increase with temperature, reaction time, and diamine concentration. Aminolysis affects greatly the geometry and surface morphology of PET fibers as observed by scanning electronic microscopy and atomic force microscopy in tapping mode. A decrease of fibers diameter and an increase of surface heterogeneity and roughness due to chemical degradation is observed. Amino groups on the surface were used to prepare glycosylated fibers by reductive amination or amidation with different carbohydrates as maltose, maltotriose, and maltohexaose. The study reveals that the yield is dependent on the initial amino groups' surface concentration and the molar mass of the carbohydrate. These surfaces could benefit to a wide range of applications in the biomedical field.

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This study deals with the grafting of carbohydrate monomers on poly(ethylene terephthalate) fibers by double argon plasma treatment. Two monomers were used: allyl alpha-D-galactopyranoside and 2-methacryloxyethyl glucoside. The quantity of grafted carbohydrates was determined by phenol/sulfuric acid colorimetric titration. The graft density was observed to vary according to the monomer used. Allyl alpha-D-galactopyranoside yields to smaller graft densities compared to 2-methacryloxyethyl glucoside, suggesting transfer reactions occurring at the surface with allyl alpha-D-galactopyranoside. Fibers with the highest graft levels were obtained with the higher monomer concentration and the lower quantity of fiber treated in a plasma reactor. The grafting density can be modulated by the monomer concentration and mass of fiber exposed in the plasma reactor. For 0.5 mg of fibers, the graft densities for 23 and 68 mM allyl alpha-D-galactopyranoside are, respectively, 18 and 35 nmol/cm2. For 0.5 mg of fibers, the graft densities for 19 and 38 mM 2-methacryloxyethyl glucoside are, respectively, 150 and 250 nmol/cm2. Comparative study without the preactivation treatment shows the efficiency of the preactivation: for a mass of fiber of 0.5 mg and a 2-methacryloxyethyl glucoside concentration of 38 mM, the grafting density without plasma pretreatment is 38 nmol/cm2. Attenuated total reflectance Fourier transform infrared spectra confirmed the anchoring of the glycopolymer onto the poly(ethylene terephthalate) surfaces. Atomic force microscopy and scanning electronic microscopy pictures indicated their morphological changes.

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This paper reports on the preparation of polyester brushes at the surface of electrically conducting materials. A two-step strategy has been worked out that consists of the electropolymerization of an acrylate under a cathodic potential, such that the polyacrylate layer is chemisorbed at the surface. In a second step, either preformed poly(epsilon-caprolactone) chains are grafted onto the polyacrylate sublayer or the ring-opening polymerization of epsilon-caprolactone is initiated from it.

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