TY - JOUR
T1 - Novel carbazole phenoxy-based methacrylates to produce high-refractive index polymers
AU - McGrath, James E.
AU - Rasmussen, Lenore
AU - Shultz, Albert R.
AU - Shobha, H. K.
AU - Sankarapandian, M.
AU - Glass, Tom
AU - Long, Tim E.
AU - Pasquale, Anthony J.
N1 - Funding Information:
The authors would gratefully like to acknowledge Prof Kathryn E. Uhrich for the use of her laboratories at Rutgers University, and for her insights and expertise, Dr Lotti Frauchiger, formerly of Rutgers University, for her expertise, and Mehmet Gordeslioglu, formerly of Virginia Tech, for his expertise with molecular modeling. The authors would like to acknowledge the Spectral Lens Group of Johnson and Johnson Vision Care, formerly Innotech, and the Naval Research Laboratory, for the funding of this project. The authors would also like to thank Metricon, Inc., for their assistance with refractive index determinations.
PY - 2006/5/17
Y1 - 2006/5/17
N2 - A novel, high-refractive index homopolymer was produced by incorporating carbazole and phenol into the methacrylate monomer structure. The reaction of phenol with 9-(2,3-epoxypropyl)-carbazole, followed by the reaction of the carbazole phenoxy-based intermediate with methacryloyl chloride or methacrylic anhydride, and recrystallization from methanol, produced a good yield of highly pure carbazole phenoxy functionalized methacrylate monomer. Subsequent free radical polymerization or UV photopolymerization of the functionalized methacrylate monomer, in addition to copolymerizations with methyl methacrylate, provided for high-refractive index materials well suited for lightweight optical applications. Unlike N-vinyl carbazole, the novel carbazole phenoxy-based methacrylate readily copolymerized with methyl methacrylate. Statistical copolymers of carbazole based methacrylates with methyl methacrylate were produced by free radical solution polymerization in DMAC or by photopolymerization in DMF. The carbazole phenoxy-based methacrylate monomer was characterized for molecular weight using gel permeation chromatography (GPC), for melting point and glass transition temperature using differential scanning calorimetry (DSC), for decomposition using thermal gravimetric analysis (TGA), and for chemical composition by one- and two-dimensional 1H nuclear magnetic resonance (NMR) spectroscopy and by elemental analysis. The AIBN initiated carbazole phenoxy-based methacrylate polymerization was followed using in situ FTIR, which showed the reaction to be complete within 40 min in DMAC at 90 °C. Refractive indices of the carbazole based methacrylate homopolymers and copolymers ranged from 1.52 to 1.63. PhotoDSC was used to determine the heat of polymerization (ΔHp) for the carbazole phenoxy-based methacrylate (ΔHp=-39.4 kJ/mol). The carbazole phenoxy-based methacrylate homopolymer had a surprisingly high onset of decomposition temperature (Tonset=316 °C). 13C NMR spectroscopy experiments and molecular modeling were used to explore the configuration of the polymerized carbazole phenoxy-based methacrylate. The lack of head-to-head linkages due to steric considerations reasonably explains the high thermal stability observed for the carbazole phenoxy-based methacrylate polymer.
AB - A novel, high-refractive index homopolymer was produced by incorporating carbazole and phenol into the methacrylate monomer structure. The reaction of phenol with 9-(2,3-epoxypropyl)-carbazole, followed by the reaction of the carbazole phenoxy-based intermediate with methacryloyl chloride or methacrylic anhydride, and recrystallization from methanol, produced a good yield of highly pure carbazole phenoxy functionalized methacrylate monomer. Subsequent free radical polymerization or UV photopolymerization of the functionalized methacrylate monomer, in addition to copolymerizations with methyl methacrylate, provided for high-refractive index materials well suited for lightweight optical applications. Unlike N-vinyl carbazole, the novel carbazole phenoxy-based methacrylate readily copolymerized with methyl methacrylate. Statistical copolymers of carbazole based methacrylates with methyl methacrylate were produced by free radical solution polymerization in DMAC or by photopolymerization in DMF. The carbazole phenoxy-based methacrylate monomer was characterized for molecular weight using gel permeation chromatography (GPC), for melting point and glass transition temperature using differential scanning calorimetry (DSC), for decomposition using thermal gravimetric analysis (TGA), and for chemical composition by one- and two-dimensional 1H nuclear magnetic resonance (NMR) spectroscopy and by elemental analysis. The AIBN initiated carbazole phenoxy-based methacrylate polymerization was followed using in situ FTIR, which showed the reaction to be complete within 40 min in DMAC at 90 °C. Refractive indices of the carbazole based methacrylate homopolymers and copolymers ranged from 1.52 to 1.63. PhotoDSC was used to determine the heat of polymerization (ΔHp) for the carbazole phenoxy-based methacrylate (ΔHp=-39.4 kJ/mol). The carbazole phenoxy-based methacrylate homopolymer had a surprisingly high onset of decomposition temperature (Tonset=316 °C). 13C NMR spectroscopy experiments and molecular modeling were used to explore the configuration of the polymerized carbazole phenoxy-based methacrylate. The lack of head-to-head linkages due to steric considerations reasonably explains the high thermal stability observed for the carbazole phenoxy-based methacrylate polymer.
KW - Carbazole functionalized methacrylate
KW - Nuclear magnetic spectroscopy
KW - Ultraviolet photo-differential scanning calorimetry
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U2 - 10.1016/j.polymer.2006.02.030
DO - 10.1016/j.polymer.2006.02.030
M3 - Article
AN - SCOPUS:33646762153
SN - 0032-3861
VL - 47
SP - 4042
EP - 4057
JO - Polymer
JF - Polymer
IS - 11
ER -