Monomer radiation grafting

Solution polymers are the second most important use for acryflc monomers, accounting for about 12% of the monomer consumption. The major end use for these polymers is in coatings, primarily industrial finishes. Other uses of acryflc monomers include graft copolymers, suspension polymers, and radiation curable inks and coatings. 

The direct radiation grafting of a vinyl monomer onto a polymer by the mutual method. 

In Table 1 a collection of some general polymer/ monomer systems in radiation grafting is given. These references are only representatives as the number of references in this area is very huge. 

Several authors have discussed the ion exchange potentials and membrane properties of grafted cellulose [135,136]. Radiation grafting of anionic and cationic monomers to impart ion exchange properties to polymer films and other structures is rather promising. Thus, grafting of acrylamide and acrylic acid onto polyethylene, polyethylene/ethylene vinyl acetate copolymer as a blend [98], and waste rubber powder [137,138], allows... 

Radiation Grafting of Functional Monomers onto Fluoropolymers... 

Investigations of radiation grafting of functional monomers onto fluoropolymers started in the late 1950s. Since that time several hundred papers and patents have been published, as have several reviews,13-16 and some specific aspects have been considered, but a broad overview has not yet appeared in print. 

Consistent with the preceeding acid work, when TMPTA is added to the monomer solutions containing either lithium salt or urea, synergistic effects are observed for the radiation grafting of styrene to polypropylene (Table IV). Again the maximum increase in yield occurs in the monomer solution corresponding to the Trommsdorff peak. 

Acid Effects in the Radiation Grafting of Monomers to Polymers, Particularly Polyethylene... 

A theory for this acid effect has been developed essentially from the wool and cellulose work (3,4). Recently, in a brief communication, we reported analogous acid enhancement effects in the radiation grafting of monomers such as styrene in methanol to nonpolar synthetic backbone polymers like polypropylene and polyethylene (5). In the present work, detailed studies of this acid enhancement effect are discussed for the radiation grafting of styrene in various solvents to polyethylene. The results are fundamentally important since most of the experiments reported here have been performed in solvents such as the low molecular weight alcohols which, unlike cellulose and wool systems, do not swell polyethylene. 

The parameters which predominantly influence the acid effect in radiation grafting of styrene monomer to polyethylene film are the structure of solvent, the concentration of monomer and the dose rate. Because these three variables are inter-related, it is difficult to predict, a priori, the conditions required to yield an optimum in grafting. In this respect the type of solvent used is particularly important. 

Most radiation graft polymerizations are carried out as heterogeneous reactions. The polymer is swollen by monomer but does not dissolve in the monomer. (For semicrystalline polymers, swelling and grafting take place only in the amorphous regions.) The typical reaction system involves equilibration of polymer with monomer followed by irradiation of the... 

Radiation-induced grafting in its simplest form involves heferogeneous sysfems, with the substrate being film, fiber, or even powder and fhe monomer fo be graffed onto fhe subsfrafe a neaf liquid, vapor, or solufion. 4i Currently, three main radiation grafting techniques are known ... 

Substituents have an effect as in conventional polymerization reactions. In radiation grafting certain substituents activate monomers, and others deactivate them.2 2 These effects can be seen in Table 5.11. 

Radiation Grafting of Miscellaneous Monomers onto Cellulose... 

Radiation grafting can be performed with the monomers being neat or dissolved. In some cases, the use of solvents can produce graft copolymers with unique properties. Solvents, which wet and swell the backbone polymers, often assist grafting. Certain additives, including mineral acids and inorganic salts such as lithium perchlorate, as well as monomers such as divinyl benzene (DVB) and trimethylolpro-pane triacrylate (TMPTA), improve grafting yields.237... 

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