2001 Progress Report: Solvent-less, Electron Beam-Cured Vinyl Ether Coating Formulations for Flexible Magnetic Media Manufacture
EPA Grant Number: R827121Title: Solvent-less, Electron Beam-Cured Vinyl Ether Coating Formulations for Flexible Magnetic Media Manufacture
Investigators: Nikles, David E.
Institution: University of Alabama - Tuscaloosa
EPA Project Officer: Shapiro, Paul
Project Period: October 1, 1998 through September 30, 2001
Project Period Covered by this Report: October 1, 2000 through September 30, 2001
Project Amount: $328,209
RFA: Exploratory Research - Environmental Engineering (1998)
Research Category: Engineering and Environmental Chemistry
Description:
Objective:The objective of this research project is to eliminate air pollution in coating processes by replacing the organic solvents with a mixture of liquid vinyl ether monomers. The applications are magnetic tape and floppy disk manufacture, which have very exacting requirements for coating uniformity. The vinyl ether monomers will be the solvent for the coating fluid. After coating and electron beam irradiation, the monomers undergo a cationic polymerization to give the binder polymer for the coating.
Progress Summary:Videotape grade cobalt-modified
-Fe2O3 particles were treated with a commercial zirconium-coupling agent.
The treated
particles were used to prepare a solventless, vinyl ether formulation, fully
loaded with 30 volume percent particles. The viscosity of this formulation
was more than a factor of 100 greater than the viscosity of a conventional,
solvent-based formulation. This formulation showed a decrease in viscosity
with increasing shear rate; a power-law dependence of the viscosity of the
shear rate. This was an important result. It was the first example of a fully
loaded solventless dispersion with workable rheological properties.
A new series of branched silane coupling agents were attached to cobalt-modified
-Fe2O3 particles and the treated particles were used to prepare a solventless
dispersion using 1,4-butanediol monovinyl ether as the solvent. The dispersion
had 30 volume percent particles and the viscosity showed a power-law shear
rate dependence, similar to that for conventional magnetic inks.
Ethyl lactate was evaluated as a green solvent for magnetic tape manufacture. The commercial binders used in videotape manufacture were not soluble in ethyl lactate, but were soluble in a 50/50 mixture of ethyl lactate and tetrahydrofuran (THF). This mixture of ethyl lactate and tetrahydrofuran (THF) replaced the mixture of methyl ethyl ketone (MEK), THF, and toluene solvents to prepare dispersions with rheological properties similar to that for a conventional magnetic ink. If one could find binders that can dissolve in ethyl lactate, the materials cost of using ethyl lactate as a solvent was 18 percent higher than the conventional formulation. If the price of ethyl lactate could be lowered to $0.57/lb, or if the price of MEK and toluene increased by 20 percent, then the materials cost for using ethyl lactate would be the same as the conventional process.
Waste polyethylene terephthalate (PET) was examined as a source of new radiation-cured oligomers. The waste PET was depolymerized by a glycolysis reaction using diethylene glycol and manganese acetate as a transesterification catalyst. The resulting hydroxyl-terminated PET oligomers had molecular weights of about 400. Attempts to put vinyl ether groups on the oligomers by a Hg2+ catalyzed transetherification with butylvinyl ether were unsuccessful. We quickly abandoned this approach because using mercury is not green chemistry. Instead the hydroxy-terminated oligomers were passed to another project where the hydroxyl groups were acrylated or methacrylated to give ultraviolet-curable PET oligomers.
Future Activities:Future activities will continue efforts to eliminate air pollution in coating processes by replacing organic solvents with liquid vinyl ether monomers.
Journal Articles on this Report: 4 Displayed | Download in RIS Format
Other project views: | All 18 publications | 4 publications in selected types | All 4 journal articles |
Type | Citation | ||
---|---|---|---|
|
Farahat MS, Nikles DE. On the UV curability and mechanical properties of novel binder systems derived from poly(ethylene terephthalate) PET waste for solventless magnetic tape manufacturing; 1. Acrylated oligoesters. Macromolecular Materials Engineering 2001;286(11):695-704. |
R827121 (2001) R827121 (Final) R826728 (Final) |
not available |
|
Farahat MS, Nikles DE. On the UV curability and mechanical properties of novel binder systems derived from poly(ethylene terephthalate) (PET) waste for solventless magnetic tape manufacturing, 2. Methacrylated oligoesters. Macromolecular Materials and Engineering 2002;287(5):353-362. |
R827121 (2001) R827121 (Final) |
not available |
|
Nikles SM, Piao M, Lane AM, Nikles DE. Ethyl lactate: A green solvent for magnetic tape coating. Green Chemistry 2001;3(3):109-113. |
R827121 (2001) R827121 (Final) R826728 (Final) |
not available |
|
Woo T, Huh JY, Nikles DE. Surface chemistry and dispersion of magnetic pigment for a solventless process. Ieee Transactions on Magnetics 2001;37(4):1634-1636 |
R827121 (2001) R827121 (Final) R826728 (Final) |
not available |
air, volatile organic compounds, VOC, solvents, pollution prevention, green chemistry, clean technologies, environmentally conscious manufacturing, chemistry, engineering, electronics. , Industry Sectors, Toxics, Air, Sustainable Industry/Business, Scientific Discipline, Engineering, Chemistry, & Physics, HAPS, air toxics, Chemistry, Manufacturing - NAIC 31-33, cleaner production/pollution prevention, treatment, flexible magnetic media, liquid vinyl ether monomers, cleaner production, Methyl ethyl ketone (2-Butanone), ambient emissions, electron beam radiation, environmentally conscious manufacturing, alternative coatings, emission control technologies, Toluene, organic contaminants, organic solvents, Methyl isobutyl ketone (Hexone), pollution prevention, monomer growth
Progress and Final Reports:
1999 Progress Report
2000 Progress Report
Original Abstract
Final Report