Aqueous dispersions of polyamides
US5723538A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1996 |
| Grant date | Mar 3, 1998 |
| Priority date | — |
| Expiry date | Oct 25, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2377/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process is provided for preparing a dispersion of a polyamide in water, said process comprising: PA1 dissolving a polyamide having an amine value of greater than about 2 in an organic solvent to form a solution of said polyamide in said solvent, said polyamide and said solvent being at a temperature below the softening point of said polyamide during said dissolving, said solution further comprising a surfactant and an inorganic alkaline material, PA1 adding sufficient water containing an acid to said solution with mixing to form an oil-in-water dispersion, the temperature of said solution and said water being below the softening point of said polyamide during said adding, the amount of said acid being sufficient to neutralize a portion of said inorganic alkaline material, but insufficient to coagulate said polyamide from the resulting oil-in-water dispersion, and PA1 removing at least a major amount of said organic solvent from said oil-in-water dispersion. The resulting dispersion is useful in preparing a coating of the polyamide, which coating is useful as an adhesive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.