TY - JOUR
T1 - Photograft polymerization of acrylate monomers and macromonomers on photochemically reduced PTFE films
AU - Noh, Insup
AU - Hubbell, Jeffrey A.
PY - 1997/11/30
Y1 - 1997/11/30
N2 - The objective of this study was to explore and optimize the photograft polymerization of acrylate monomers and macromonomers upon premodified poly(tetrafluoroethylene) (PTFE) substrates, with a view toward applying these grafted materials as biomaterials. PTFE films were photochemically reduced by exposure to short wavelength ultraviolet (UV) light in the presence of the reducing agents, i.e., diphenyl ketyl radical anion, generated from a solution of benzophenone and sodium hydride in dimethylformamide (Noh et al., J. Polym. Sci. A, Polym. Chem., 35, 1499 (1997)). The photochemically reduced PTFE films were subsequently modified by photograft polymerization of acrylic acid, acrylamide, and poly(ethylene glycol) monoacrylate (PEG-Ac) by employing long wavelength UV irradiation with benzil dimethyl ketal as an initiator. The photochemically reduced PTFE films were good substrates for photograft polymerization, leading to surfaces with chemical compositions close to those of the respective homopolymers as determined by electron spectroscopy for chemical analysis. Photograft polymerization of PEG-Ac on the photochemically reduced surface was also explored with different concentrations (1, 2, 4, 6, and 8%; v/v) and molecular weights (200, 400, 1000, and 2000 g/mol) of PEG-Ac, different durations (5, 10, and 20 min) of long wavelength UV irradiation, and different concentrations (0.1, 0.2, 0.4, and 0.8%; v/v) of benzil dimethyl ketal. Higher concentrations and lower molecular weights of PEG-Ac generally led to more extensive photograft polymerization, whereas the concentration of benzil dimethyl ketal and duration of UV irradiation did not substantially influence the extent of photograft polymerization.
AB - The objective of this study was to explore and optimize the photograft polymerization of acrylate monomers and macromonomers upon premodified poly(tetrafluoroethylene) (PTFE) substrates, with a view toward applying these grafted materials as biomaterials. PTFE films were photochemically reduced by exposure to short wavelength ultraviolet (UV) light in the presence of the reducing agents, i.e., diphenyl ketyl radical anion, generated from a solution of benzophenone and sodium hydride in dimethylformamide (Noh et al., J. Polym. Sci. A, Polym. Chem., 35, 1499 (1997)). The photochemically reduced PTFE films were subsequently modified by photograft polymerization of acrylic acid, acrylamide, and poly(ethylene glycol) monoacrylate (PEG-Ac) by employing long wavelength UV irradiation with benzil dimethyl ketal as an initiator. The photochemically reduced PTFE films were good substrates for photograft polymerization, leading to surfaces with chemical compositions close to those of the respective homopolymers as determined by electron spectroscopy for chemical analysis. Photograft polymerization of PEG-Ac on the photochemically reduced surface was also explored with different concentrations (1, 2, 4, 6, and 8%; v/v) and molecular weights (200, 400, 1000, and 2000 g/mol) of PEG-Ac, different durations (5, 10, and 20 min) of long wavelength UV irradiation, and different concentrations (0.1, 0.2, 0.4, and 0.8%; v/v) of benzil dimethyl ketal. Higher concentrations and lower molecular weights of PEG-Ac generally led to more extensive photograft polymerization, whereas the concentration of benzil dimethyl ketal and duration of UV irradiation did not substantially influence the extent of photograft polymerization.
KW - Acrylamide
KW - Acrylic acid
KW - Benzophenone
KW - Diphenyl ketyl radical anion
KW - PEG monoacrylate
KW - Photograft polymerization
KW - PTFE
KW - Surface modification
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U2 - 10.1002/(SICI)1099-0518(19971130)35:16<3467::AID-POLA14>3.0.CO;2-D
DO - 10.1002/(SICI)1099-0518(19971130)35:16<3467::AID-POLA14>3.0.CO;2-D
M3 - Article
AN - SCOPUS:0031275628
VL - 35
SP - 3467
EP - 3482
JO - Journal of Polymer Science, Part A: Polymer Chemistry
JF - Journal of Polymer Science, Part A: Polymer Chemistry
SN - 0887-624X
IS - 16
ER -