Graft polymerization on magnesium oxide surface

Preparation of Poly(acrylic acid) Grafted Multiwalled Carbon Nanotubes by a Two-Step Irradiation Technique

“…On the other hand, same as other surface modification methods, to fulfill the modification of functional composites by radiation grafting, the surface of the materials is often required with active groups, such as hydroxyl, carbonyl, and carboxyl groups. 47 The radiation-induced graft polymerization is then initiated through these groups on the surface of the materials; the hydroxyethyl groups also act as the initiating sites of the polymerization of acrylic acid. That is to say, in our case the PAA polymer chains grafted not only directly to the skeleton of the tubes but also to the pregrafted hydroxyethyl groups.…”

Surface modification on nanoscale titanium dioxide by radiation: Preparation and characterization

“…Although many studies on graft polymerization of vinyl monomers to inorganic materials by various initiating methods have been published, it is generally quite difficult to initiate graft polymerization on the surface of inorganic materials with common chemical initiating methods. Ionizing radiation can directly activate a substance, and induce graft polymerization of vinyl monomers in some particular conditions 18, 19…”

“…In previous papers, we have reported mechanism of graft reaction of vinyl polymers onto magnesium oxide and activated alumina initiated by surface radicals formed by radiation 18, 19. Further, according to our experimental observation, the graft polymerization is a kinetic controlling process too.…”

“…Although some mechanisms of graft polymerizations induced by ionizing irradiation have been discussed, most mechanisms are still obscure, and many inorganic compound materials cannot be induced to graft polymerization with this method under our experimental conditions. Because the grafted inorganic materials are made from different elements and compositions, and have different radiation chemical effects, the graft reaction mechanisms could be different from one another 18, 19, 28, 29. With regard to compounds with empty orbit atoms, such as aluminum and titanium atoms, it is believed that they lose an oxygen atom by which compounds with aluminum atoms produce a radiation default in aluminum oxide (Al 2 O 3 ) by irradiation.…”

“…Obviously, the methods of indirect graft polymerizations are relatively fussy, and easily introduce low molecular weight compounds that possess potentially cytotoxic reaction. Ionizing radiation is a direct, effective, attractive method for contacting inorganic–organic materials interface and modifying surfaces of inorganic materials compared with other initiating means of graft polymerization 18, 19. The grafting reaction also prepares biofunctional materials with cell recognizability.…”