Acrylic monomer photografting

Acid-containing polymers, hydrogen bonding, 260 Acrylic monomers photografting, 172,173/,174 UV curing, 212-213 Acrylic-acrylic block copolymers, synthesis, 259... 

Photografting of Acrylic Monomers onto Polyolefin Surfaces... 

Another interesting case is the self-initiation of some acrylic and styrenic monomers upon UV irradiation. Since this process is quite slow, a photoinitiator is normally required. Recent findings on the self-initiation of maleic anhydride, [ 10] styrene, [11] and anumber of acrylic monomers [12] have demonstrated that photopolymerization and photografting could possibly be achieved without using photoinitiators or sensitizers. 

H.U. Zaman, R.A. Khan, M.A. Khan, and M.D.H. Beg, Physico-mechanical and degradation properties of biodegradable photografted coir fiber with acrylic monomers. Polym. Bull. 70, 2277-2290 (2013). 

Decker, C. and Zahouily, K., Surface modification of polyolefins by photografting of acrylic monomers, Macromol. Symp., 1998,129, 99-108. 

Table XI. Role of UV Dose in Synergistic Effect of Acrylate and Methacrylate Monomers with Inorganic Salts(L) in Photografting Styrene to Polypropylene3...

Apart from the chemical effects of solvent as hydrogen donor, being heterogeneous systems, an important role of solvent is to provide appropriate reaction sites on the balance of solvent interactions with base polymer and growing graft chain. For the study of solvent effects, AM is not an adequate monomer since it is scarcely soluble in non-polar solvents. Instead, acrylic acid(AA) was employed and photografting was conducted as shown in Figure 8. 

Photogirafting.— The photografting of vinyl monomers on to polymer substrates continues to be a widely studied method for improving their properties. Nylon 6 appears to have attracted particular interest in this respect. Acryl-... 

Tests of the light stabilizing activity of monomeric HAS and the corresponding homo- and copolymers reveal mostly better properties of the monomers if physical persistence is not the decisive testing factor [8]. This was found e.g. in comparison of the functionalized urethane 182 and its copolymers with styrene or methyl methacrylate [303], The macromolecular architecture is expressed very distinctly. For example, a PP photografted HAS-functionalized acrylate was more efficient than the respective monomer or homopolymer. Another observation performed with A-(2,2,6,6-tetramethyl-4-piperidyl)methacry-lamide, piperidyl acrylate and methacrylate, their homopolymers and copolymers with dodecyl methacrylate and octadecyl acrylate revealed that the stabilizing effect in PP was in favour of copolymers [304]. Similar HAS-functionalized monomers were copolymerized with styrene. In this case, the copolymers were substantially less efficient in PS than the monomers. Masterbatches of PP-bound HAS prepared by reactive processing imparted a comparable effectivity as conventional HAS when tested at an equimolar basis [298]. 

Kondo, T., Koyama, M., Kubota, H. et al. 1998. Characteristics of acrylic acid and N-isopropylacrylamide binary monomers-grafted polyethylene film synthesized by photografting. J Appl Polym Sci. 67 2057-2064. 

The melt processed PLA, PHA, and their blend films were hydrophobic. However, surface-confined photopolymerization of hydrophilic monomers (acrylamide and acrylic acid) yielded significantly reduced water contact angles as summarized in Table 1. To characterize the modified surfaces even further, the films were evaluated using ATR-FTIR and typical spectra for neat and surface-modified films are shown in Figure 1. All spectra showed the -C=0 stretch in the amide functionality of PA Am at wavenumber 1654 cm" and an amide II peak was observed at 1550 cm", confirming the successful photografting of PAAm. 

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