Polymeric Materials for Use as Binders and Transparent Films.
Abstract
The purpose of this program was to develop two types of film forming materials for use as binders in pigmented coatings. Curing of a polydimethylsiloxane, for use as ultraviolet transparent binder, was accomplished with curing agents that could be subsequently removed from the coating. Coatings cured and irradiated with ultraviolet light in vacuum turned yellow. The polydimethylsiloxane was distilled under very low pressure, and the undistilled portion was found to be more stable to ultraviolet light. Transparent coatings prepared from the purified polydimethylsiloxane and the curing agents, as well as similar coatings pigmented with Mono-90 clay, were subjected in vacuum to 300 solar equivalent hours of ultraviolet, 1 ke V protons, and 20 e V electrons. There was no change in the solar absorptance of the transparent coatings which were cured with tetramethylammonium hydroxide. Increasing change was noted in coatings cured with tetramethylammonium hydroxide plus poly(methylsiloxane), tetramethylguanidine (retained in the coating), and ammonia. Effects were minimized and equalized by the pigment. Several fluorinated polymers were tested for use as infrared and visible transparent binders. Poly(perfluoroalkylenetriazine) and a chlorotrifluorethylene-vinylidene fluoride copolymer were poorer than hexafluoropropylene-vinylidene fluoride copolymers. Coatings containing 75 percent tantalum oxide in the hexafluoropropylene- vinylidene fluoride copolymer and cured with 1,4-diazabicyclooctane withstood heating in air for 1000 hours at 274^C. (Author, modified-PL)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1971
- Accession Number
- AD0884244
Entities
People
- Richard I. Akawie
Organizations
- Hughes Aircraft Company