Grafted polyethylene films methacrylic acid

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. 

Figure 6 and 7. Surface grafting of polyethylene (PE) and polypropylene (PP) films with acrylic acid (AA), methacrylic acid (MAA), crotonic acid (CA), tiglic acid (TA), 3-methylcrotonic acid (3-MCA) and a-methyl cinnamic acid (a-MCA), measured by absorption of visible light after grafting for 2 min. with vapor phase method and dipping in aqueous solution of crystal violet. 

Because the free radical initiated graft reaction can also lead to the cross-linking of polyethylene, copolymers of ethylene and with acrylic acid (184,185), glycidyl methacrylate (184,186), methacrylic acid and 10-undecenoic acid (187-189) were synthesized to compatibilize polyethylene/polyamide blends. The poly (ethylene-co-methacrylic acid) ionomers neutralized by sodium (184) and zinc (45,118,190-192) has also used as compatibilizers. High energy irradiation, used to modify the surface of fibers or films at beginning, was also used to compatibilize the polyethylene/polyamide blends (193-196). 

The hydrophilicity of the catheter surface Is an Important criterion for enhancing lubricity of the biomaterial and has been Introduced by UV induced grafting of polar monomers [37]. In an attempt to produce balloon catheters, polyethylene films and catheters are grafted with dimethylaminoethyl methacrylate (DMAE-MA) and acrylic acid under UV irradiation [38]. The acrylic acid leads to much higher graft density as compared to the acrylate monomer and an autoacceleration in the grafting of acrylic acid is observed (Fig. 6). The grafting of DMAEMA, on the other hand, does not show any acceleration and levels off much faster. In an-... 

Another example has been presented by Hsuie. Polyethylene films irradiated in the presence of air and stored for a couple of hours have been immersed into an aqueous solution of acrylic or methacrylic acid containing some Fe salt. In this case, the grafting process is initiated by the redox reaction between the peroxide functions and the iron salt. The grafting ratio first increases with time and then reaches a plateau when the peroxide sites have been consumed. It is an increasing function of the irradiation dose and of the monomer concentration. 

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