Photografting of acrylonitrile and methacrylic acid on polyethylene film under air atmosphere

Abstract

SYNOPSISPhotografting of acrylonitrile (AN) and methacrylic acid ( M A A ) on low-density polyethylene film (thickness 70 pm) , on which benzophenone was coated earlier, was investigated a t 60°C in water medium under air atmosphere. In the case of AN monomer, where grafted polymer was formed predominantly, oxygen in the system promoted the formation of both grafted polymer and homopolymer. With MAA monomer, in which homopolymer was formed preferentially compared to the formation of grafted polymer, the formation of homopolymer was accelerated by the presence of oxygen while suppressing that of grafted polymer. The formation of polyethylene peroxides by photoirradiation seemed to be a factor for the accelerated polymerization under air atmosphere. It was found that additives such as hydrazine and metallic ions (Fez+, Cu2+, and Ni2+) are useful for enhancing the photografting under air atmosphere.

Observations and analysis of electrokinetically driven particle trapping in planar microelectrode arrays

“…Grafting polar monomers onto the surfaces of polyolefin films yields improved adhesion of these modified polymers to other substrates1–3 and improved hydrophilicity or compatibility with polar materials. For surface modification, the photoinitiated grafting of polar monomers, such as acrylic acid,4 hydroxypropyl acrylate,5 acrylonitrile, methacrylic acid,6 glycidyl acrylate,7 acrylamide,8, 9 and methyl methacrylate,10 onto polyolefins has been studied extensively to address a variety of industrial and academic interests. Currently, most of the photochemical grafting approaches have been limited to surface modification, whereas thermal initiators (e.g., peroxides) have been used for solution grafting or molten‐state grafting of bulk polymers.…”

Examination of the role of oxygen in the photografting of methacrylic acid on a polyethylene film with a mixed solvent consisting of water and organic solvents

“…In the photografting system, a deaerated system is usually employed for the removal of oxygen; this generally inhibits the radical polymerization of vinyl monomers. However, the photografting of vinyl monomers under air11–16 has also been investigated. One author12 reported that the photografting of methacrylic acid (MAA) and acrylonitrile on a benzophenone‐coated low‐density polyethylene film was successfully performed under air.…”

“…However, the photografting of vinyl monomers under air11–16 has also been investigated. One author12 reported that the photografting of methacrylic acid (MAA) and acrylonitrile on a benzophenone‐coated low‐density polyethylene film was successfully performed under air. Efforts have been made to enhance the photografting reaction under air, and various additives, such as hydrazine, metallic ions, riboflavin, and NaIO 4 , have been employed 12–16.…”

“…One author12 reported that the photografting of methacrylic acid (MAA) and acrylonitrile on a benzophenone‐coated low‐density polyethylene film was successfully performed under air. Efforts have been made to enhance the photografting reaction under air, and various additives, such as hydrazine, metallic ions, riboflavin, and NaIO 4 , have been employed 12–16. However, it was observed in our previous work17 for the photografting of MAA on a linear low‐density polyethylene (LLDPE) film in mixed solvents consisting of water and an organic solvent, such as acetone or methanol, that the component of the organic solvent in the mixed solvent remarkably influenced both the grafting behaviors and the location of MAA‐grafted chains in the LLDPE film substrate.…”

Photografting of acrylic acid on high density polyethylene powder in vapour phase

“…The radicals formed during UV irradiation are restricted to the surface; thus the location of grafting is limited to the surface region of the polymer materials without any changes of the bulk properties. Since the pioneering work by Oster and co‐workers5, 6 in 1950s, the literature7–14 about surface photografting concentrated on films, fibres and other final products. It seems that no work was ever reported on the surface graft polymerization on PE powder.…”