Methods for the preparation of oriented thin large-area single crystals of diacetylenes and polydiacetylenes
US4698121A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1985 |
| Grant date | Oct 6, 1987 |
| Priority date | — |
| Expiry date | Feb 26, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S117/919
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Methods for preparing thin large-area single crystals of diacetylenes and polydiacetylenes having surface dimensions greater than or equal to about 0.1 mm on all sides and a uniform thickness less than or equal to about 100 microns. The methods involve forming a liquid layer, preferably by melting crystals of a pure diacetylene monomer between two opposed surfaces, one surface being movable with respect to the other; applying pressure to the molten monomer layer disposed between the two surfaces; shearing the molten layer by sliding the movable surface in a single direction that is in a straight line across the molten monomer layer while keeping the molten monomer layer under constant pressure; and crystallizing the shorn molten monomer layer while the shorn molten monomer layer is kept under constant pressure to form a thin large-area single crystal of pure diacetylene monomer. The method for preparing thin large-area single crystals of polydiacetylene further involves exposing a surface of the thin large-area single crystal of diacetylene monomer to ultraviolet or gamma radiation to form a thin large-area single crystal of polydiacetylene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.