Radiation grafting of monomers

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. 

Methods for Enhancing Ultraviolet and Radiation Grafting of Monomers to Cellulose and Derivatives to Improve Properties of Value to Conservation... 

Effect of temperature on the degree of grafting in radiation grafting of monomers on PP and PET fibers using radiation trapped radical technique. 

Recently a method was reported for enhancing the radiation grafting of monomers to polymers by the simple addition of mineral acid to the grafting solution >Under some experimental conditions organic acids act in the same manner >. Extensive work on this acid effect has been published for the radiation copolymerisation of styrene to cellulose wool, the polyolefins >PVC and polyesters. The acid effect has also been extended to the grafting of monomers other then... 

Rowell and R.A. Young, eds. Academic Press, New York, (1978). J.Lo Garnett and N.T. Yen, Acid effects in the radiation grafting of monomers to polymers, particularly polyethylene, ACS Symp.Ser. 121 243 (1980). 

H. Barker, J.L. Garnett, R.Levot and M.A. Long, Use of Additives to enhance radiation grafting of monomers to poly (vinyl chloride) and application of these PVC copolymers to immobilization of enzymes and heterogenization of homogeneous metal complexes, J.Macromol.Sci-Chem. A12(2) 261 (1978). C.H.Ang, J.L. Garnett and R. Levot, unpublished work. 

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

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. 

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. 

Radiolysis Effects. Radicals formed in solvent (SH) and trunk polymers (PH) are important in the grafting of monomers (MH) with gamma radiation. With polymers such as polyethylene, grafting sites are formed by direct bond rupture (Equation 1). Additional sites are also... 

Radiation processing of monomers and polymers by electron beam, such as polymerization and copolymerization of monomers, cross-linking, grafting, and degradation of polymers, is induced by these different chemically reactive species. ... 

Radiation Grafting of Miscellaneous Monomers onto Cellulose... 

One of the most suitable systems for grafting is a radiation-sensitive polymer in the presence of radiation-insensitive monomer. With this combination, the grafting of monomer to the polymer backbone is favored... 

Direct Radiation Grafting of Polymer in the Presence of Vinyl Monomer. This leads to the formation of free radicals on both polymer and monomer, resulting in graft polymerization and homopolymerization. The extent of homopolymerization depends on the sensitivity of the monomer used. 

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 ... 

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