Fire retardant fine particulate expandable styrene polymers
Abstract
Abstract Fire retardant, expanded styrene polymer shaped objects are prepared by: (a) mixing styrene monomer or a mixture thereof with at least one comonomer, an expanding agent and a fire retardant, organic halogen compound in a aqueous dispersion; (b) adding to (a) either before or during polymerization from about 0.0001 to 0.1 percent by weight esters soluble in the organic phase of (a), these esters of aliphatic dicarboxylic acids and aliphatic epoxy alcohols having at least 11 carbon atoms; (c) polymerizing the aqueous dispersion of (a) and (b) using radical forming initiators at a temperature of about 80 DEG to 130 DEG C.; (d) separating bead polymers having diameters between about 0.4 and 3 mm; (e) pre-foaming the beads; (f) ageing the pre-foamed beads; and (g) final forming the aged and pre-foamed beads in a pressure resistant mold.
Inventors
- 👤 Josef K. Rigler
- 👤 Ekkehard Wienhofer
- 👤 Horst Leithauser
- 👤 Karl Trukenbrod
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-28 | 1987-05-30 | 1987-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-28 | 1991-05-30 | 1991-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-28 | 1995-05-30 | 1995-11-29 | $7700.00 | Window Closed / Lapsed |