Grafting by radiation

Also, acrylonitrile may be grafted by radiation to lignosulfonates with grafting yields of about 20%. However, the compatibility of the grafted product as a filler in SBR seems to be inferior to that of the original lignosulfonate (57). 

Figure III - 16. Schematic repre-sentaiion of grafting by radiation [14],...

Grafting by means of radiation is by far the most popular synthetic technique for modification of polymers, and... 

Advanced development of ion-selective films has been attempted by radiation grafting of methacrylic acid on polyethylene films, and combination of this with cellophane are also being tested. Polyamide fleece impregnated with regenerated cellulose, is another option for zinc-silver oxide batteries. 

The creation of active sites as well as the graft polymerization of monomers may be carried out by using radiation procedures or free-radical initiators. This review is not devoted to the consideration of polymerization mechanisms on the surfaces of porous solids. Such information is presented in a number of excellent reviews [66-68]. However, it is necessary to focus attention on those peculiarities of polymerization that result in the formation of chromatographic sorbents. In spite of numerous publications devoted to problems of composite materials produced by means of polymerization techniques, articles concerning chromatographic sorbents are scarce. As mentioned above, there are two principle processes of sorbent preparation by graft polymerization radiation-induced polymerization or polymerization by radical initiators. We will also pay attention to advantages and deficiencies of the methods. 

Mao C, Zhu AP, Qiu YZ, Shen J, and Lin SC. Introduction of 0-butyrylchitosan with a photosensitive hetero-bifunctional crossUnking reagent to silicone rubber film by radiation grafting and its blood... 

Trapped radicals on samples with different storage conditions and reaction conditions are usually determined by ESR. Modification of PVC by radiation-grafting technique is an attractive method to improve the mechanical strength, printing ink adhesion, and adhesive receptance. Wang... 

Our library synthesis was carried out with a set of 27 tube-shaped solid phase synthesis support, called MicroTubes. These supports are prepared by radiation grafting of polystyrene ( — 350 pmol) onto polypropylene tubes, chemically functionalizing the polystyrene with aminomethyl groups to afford about 55 imol of amine per tube, inserting a reusable Rf ID tag into each tube, and heat-sealing the tube ends to prevent loss of the tag. The chemical conversion of all 36 aminomethyl tubes was carried out simultaneously using standard procedures with rink amide linker, each with —46 pmol of available amine per tube.1 2... 

Among other methods to render surfaces of implanted materials bio-compatible, in particular to prevent them from initiating blood clotting, one may activate the surfaces by radiation and then graft water soluble, or negatively charged, polymers onto the active sites. 

Fig. 24. LS at zero concentration for solutions of ny-lon-6/acrylic acid copolymers prepared by radiation grafting1 os The degrees of grafting are (a) 0.038, (b) 0.056, (c) 0.123...

Journal of Applied Polymer Science 37,No.8,April 1989,p.2153-64 PREPARATION OF HYDROPHILIC POLYETHYLENE FOAM OF OPEN CELL TYPE BY RADIATION GRAFTING OF ACRYLIC ACID Kaji K Hatada M Yoshizawa I Kohara C Komai K JAPAN,ATOMIC ENERGY RESEARCH INSTITUTE SANWAKAKOCO. 

Three types of reactive species are formed under irradiation and may become trapped in polymers ionic species, radicals, and peroxides. Little is known about the role of ions in the chemical transformations in irradiated polymers. Long-lasting ions arise, as demonstrated by radiation-induced conductivity, and may become involved in postirradiation effects. The presence of trapped radicals is well-established in irradiated polymers, but certain problems remain unsolved concerning their fate and particularly the migration of free valencies. Stable peroxides are produced whenever polymers are irradiated in the presence of oxygen. Both radicals and peroxides can initiate postirradiation grafting, and the various active centers can lead to different kinetic features. 

Graft polymers of cotton cellulose and acrylonitrile initiated by radiation. Text. Res. J. 31, 988 (1961). 

Chemical groups capable of ionic binding of heparin may be introduced onto the polymer surface by radiation grafting of ionogenic monomers, e.g., 2- or 4-vinyl-pyridine, dimethylaminoethyl methacrylate, etc. 64,65). Heparinization proceeds as shown below ... 

Seko, N., Basuki, F Tamada, M. and Yoshii, F. (2004) Rapid removal of arsenic(V) by zirconium(IV) loaded phosphoric chelate adsorbent synthesized by radiation induced graft polymerization. Reactive and Functional Polymers, 59(3), 235-41. 

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