Claims
- 1. The biocompatible material prepared by the following steps:
- a. alkali-cellulose is prepared by steeping cellulose pulp using bisulfite acid in a sodium hydroxide solution followed by drying and pressing to achieve a weight of dry cellulose of between 30 and 40%,
- b. the alkali-cellulose is then sulfurated using carbon sulfide, and least in stoichiometric quantities, in order to obtain sodium xanthate,
- c. the sodium xanthate is dissolved in a diluted sodium hydroxide solution to obtain a viscose solution containing cellulose and sodium hydroxide in well-determined proportions,
- d. the viscose obtained is submitted to heat treatment so as to provoke the coagulation of the viscose and to treatment for removal of the sulfur, so as to obtain an amorphous material with rubber-like characteristics,
- e. and the material obtained is dried.
- 2. The biocompatible material in accordance with claim 1, wherein the coagulation of the cellulose is first provoked by a heat treatment and the sulfur is then removed by washing with water and a product which is reactive with the sulfur.
- 3. The biocompatible material of claim 2, wherein said sulfur-reactive product is sodium sulfite, sodium carbonate or both.
- 4. The biocompatible material in accordance with claim 2, wherein the removal of sulfur by washing is carried out in the presence of microwave heating.
- 5. The biocompatible material in accordance with claim 1, wherein the sulfur is partially removed from the viscose solution by treatment with a product which is reactive with the sulfur, prior to provoking the coagulation.
- 6. The biocompatible material in accordance with claim 5, wherein the sulfur removal phases by treatment with a product which is reactive with the sulfur, and washing with water are alternated with the coagulation phases.
- 7. The biocompatible material in accordance with claim 1, wherein the water is removed by heat pressing.
- 8. The biocompatible material in accordance with claim 1, wherein the water is removed in a mold so as to directly obtain a product having the desired shape.
- 9. The biocompatible material in accordance with claim 1, wherein reinforce fibers are incorported in the viscose solution.
Priority Claims (1)
Number |
Date |
Country |
Kind |
86 10331 |
Jul 1986 |
FRX |
|
Parent Case Info
This a division of application Ser. No. 07/074,047, filed on Jul. 16, 1987, now U.S. Pat. No. 4,904,258.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3901236 |
Assarsson et al. |
Aug 1975 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
74047 |
Jul 1987 |
|