Grafting of poly

Finally, surface properties of PTFEP were modified photochemically by light-induced grafting of poly(AT,Ar,-dimethylacryl amide) onto the film surface of this material to achieve a remarkable enhancement of its hydrophilicity [513]. 

A. Archut, S. Gestermann, R. Hesse, C. Kauffmann, F. Vogtle, Selective Activation, Different Branching and Grafting of Poly(propyleneamine)-Dendrimers , Synlett 1998, 546-548. 

The grafting of poly(ethylene oxide) chains onto PES and a poly(aryl ether) (PAE) has been used to increase the hydrophilicity of these non-ionic poly-mers. These systems were then blended with SPES. SEM analysis showed... 

Scheme 1 Repetitive step-by-step synthetic scheme leading to formation of a hyper-branched graft of poly(acrylic acid) on a mercaptoundecanoic acid self-assembled mono-layer on a supported gold film...

Scheme 2 Photolithographic process for preparing patterned hyperbranched grafts of poly(acrylic acid)...

Riva R, Schmeits S, Jerome C, Jerome R, Lecomte P (2007) Combination of ring-opening polymerization and click chemistry toward functionalization and grafting of poly( -caprolactone). Macromolecules 40 796-803... 

Surface-initiated ATRP was applied not only on planer substrates but also on various kinds of flne particles. The latter systems will be reviewed separately in Sect. 5.1. Porous materials are also fascinating targets for chromatographic application making use of the unique structure and properties of high-density polymer brushes. Wirth et al. were the first to report the grafting of poly(acrylamide) (PAAm) on a porous silica gel [109,110]. 

Grafting and Stabilizers. The degree of grafting of poly(vinyl acetate) (PVAc.) on poly(vinyl alcohol) (PVA) and other stabilizers during emulsion polymerization strongly affects latex properties such as viscosity, rheology, and polymer solubility. 

In the works of Ferruti et al.83,84), there has been reported a method for heparinization of plasticized polyvinyl chloride which was pre-modified by grafting of poly-aminoamines. The surface concentration of ionically bound heparin was 1.2 ng/cm2. Heparin can be eluted off the polymer in a narrow pH range of 10.8 to 11.4. 

Elastomers, prepared by free-radical initiated copolymerization of ethyl acrylate with cellulose to several hundred percent extent of grafting of poly (ethyl acrylate) onto cellulose, exhibited rubber-like behavior and second-order transition temperatures. Cellulose-poly (ethyl acrylate) elastomers had transition temperatures below —35°C, about — 20°C, and below 5°C when measured in ethyl acetate, dry air, and water, respectively (43, 44). 

Saegusa et al. [81] reported on the grafting of poly (ethyleneimine) on poly(p-chloromethylstyrene) (PS-g-PEI). 

Radiation-induced grafting29 was used for the preparation of low-cost polyelectrolyte membranes needed for fuel-cells30. Guzman-Garcia and coworkers29 studied the grafting of poly(styrenesulphonic acid)on polystyrene on a copolymer of poly(tetrafluoroethylene) with polystyrene, and with a copolymer of poly(tetrafluoroethylene) with poly(perfluoropropylene). 

Fig. 6 Radical grafting of poly(ethylene-co-methacrylate) onto polysiloxane [52]...

Conventional ABS polymers are blends of poly (styrene-coacrylonitrile) with either poly (butadiene-coacrylonitrile) or a graft of poly-(styrene-coacrylonitrile) onto a rubbery spine. To confer flame-resistance on either ABS system using DBPF as a fourth monomer, the major component should be a styrene-acrylonitrile-DBPF terpolymer since the resinous component is the major one. The composition of such a terpolymer is restricted by two considerations (1) it should contain sufficient acrylonitrile to impart the resistance to solvent attack which is characteristic of ABS polymers, and (2) the amount of DBPF should be sufficient to give a useful level of flame resistance. 

Trivedi, A.H. Kwak, S. Lee, S. Grafting of poly (vinyl chloride) and polypropylene with styrene in a supercritical CO2 solvent medium synthesis and characterization. Polym. Eng. Sci. 2001, 41, 1923-1937. 

Filler particles can be modified to decrease flocculation. Kaolin particles modified by a graft of poly(ethylene oxide) showed an increase in the upper critical flocculation temperature. Stabilization of particle dispersion was due to an enhanced steric stabilization." ... 

Figure 6.8. Effect of temperature on the grafting of poly(THF) onto carbon whisker. [Adapted, by permission tfom, Tsubokawa N, Yoshihara T, Coll. Surfaces, 81, 1993, 195-201.]...

There was a strong possibility that initiation occurred via photosensitized formation of hydrogen peroxide on the metal oxide surface followed by desorption and subsequent photolysis of hydrogen peroxide to form free radicals. Radicals formed by this means would lead to abstraction of hydrogen from the fiber surface and subsequent grafting of poly(methyl acrylate) at these sites. 

Smets, DeWinter and Delzenne attached eosin units to polyvinyl-amine) through the amino groups. Photopolymerization was initiated at the eosin sites, yielding grafts of poly(vinylamine-eosin-poly-(acryla-mide) where X is —CONH2. 

By irradiation of natural rubber containing benzophenone, and in contact with aqueous acrylamide, Osier and Shibata 12> showed that grafts of poly(acrylamide) could be formed along the rubber backbone chain. 

Related to the electroinitiations with Fe2+/peroxides is the paper by Mendis, Pemawansa and Hettiarachchi on the grafting of poly(methyl methacrylate) on natural rubber latex43. In this case Fe2+ ions are already in solution and, as the authors tentatively propose, MMA peroxides formed anodically could start the graft polymerization. 

Table XVII shows the grafting of poly (styrene-alt-acrylonitrile) on nitrile rubber precomplexed with EASC. This system is heterogeneous since addition of EASC to the polymer solution causes the polymer to agglomerate or precipitate.

Exposure of the n-type films to either liquid (styrene, methyl methacrylate) or gaseous (ethylene oxide, isoprene) monomers resulted in polymerization. Much of our initial work has focused on grafting of poly(ethylene oxide) (PEO) to (CH)X in an effort to render the (CH)X surface more hydrophilic and to provide covalent attachment of a material capable of functioning as a solid electrolyte (12). Films of n-type (CH)X were exposed to dry (CaH2-treated), gaseous ethylene oxide in the range 55-75°C with initial pressures being ca. 500 torr. Reaction times were typically 5 hours. The films were washed with dry, 02-free methylene chloride to remove non-covalently bound PEO and then with deaerated H2O to protonate oxyanions and remove the NaOH byproduct. The presence of bound PEO after extraction was confirmed by IR spectroscopy. 

The grafting of poly-3 methylthiophene (PMeT) on the Pt wire involves the oxidation of the monomer, 3-methylthiophene, 0.5 M in CH3CN + 0.5 M N(C4H9)4S03CF3 at 1.35 V/SCE (satured calomel electrode). The polymer is formed directly in its doped conducting state. This modified electrode is put in a 3 mm-thick electrochemical cell composed of a Teflon ring covered by two Kapton windows. An aqueous copper... 

Graft polymers are named in the same way as a substituted polymer but without the ending yl for the grafted chain the name of a regular polymer, comprising Z units in which some have grafts of poly(A) is poly[Z/poly(A)Zj Star polymers are treated as a central unit with substituent blocks, as in tet-rakis(polymethylene)sIlane . " ... 

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