Production of copolymers
Abstract
Abstract IN THE SUSPENSION POLYMERIZATION OF A MIXTURE OF TWO UNEQUALLY REACTIVE MONOMERS, SUCH AS STYRENE AND DIVINYL BENZENE, IN A SUSPENSION MEDIUM CONTAINING A STABILIZER WHICH FORMS FILMS ON GLOBYLES OF THE MONOMER MIXTURE, THE PROPORTION OF THE MORE REACTIVE MONOMER IN THE UNREACTED MIXTURE IN THE GLOBULES TENDS TO DECREASE CONTINUOUSLY, SO THAT THE RESULTANT BEADS ARE NOT HOMOGENEOUS IN COMPOSITION. THE INVENTION IMPROVES THE HOMOGENEITY BY ADDING MORE MONOMER MIXTURE IN THE FORM OF AN EMULSION AS THE POLYMERIZATION PROCEEDS, THE EMULSION CONTAINING A PROGRESSIVELY INCREASING PROPORTION OF THE MORE REACTIVE MONOMER. TO ENABLE THE EMULSIFIED MONOMERS TO ENTER TO GLOBULES, THE STABILIZERS FILMS ARE KEPT THIN.
Inventors
- 👤 L Roubinek
- 👤 T Kressman
Bibliographic Details
Claims Analysis
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |