Polysulfide-based polyurethane sealant for insulating glass
US6322650A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1999 |
| Grant date | Nov 27, 2001 |
| Priority date | — |
| Expiry date | Apr 15, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31533
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An insulated glass sealant having the best characteristics of polysulfides and polyurethanes rather than the worst is made from a polysulfide-based polyurethane which, in turn, is derived from a mixture of hydroxyl terminated polysulfides having a structure represented by the following formula: EQU RCH.sub.2 CH.sub.2 OCH.sub.2 OCH.sub.2 CH.sub.2 S[SCH.sub.2 CH.sub.2 OCH.sub.2 OCH.sub.2 CH.sub.2 S].sub.n SCH.sub.2 CH.sub.2 OCH.sub.2 OCH.sub.2 CH.sub.2 R. PA1 wherein R.dbd.HO(CH.sub.2).sub.y SS, y is from 2 to 6, and n is such that the molecular weight is from about 2500 to about 4000. The improved sealant of this invention is prepared by a one-step procedure wherein the hydroxyl terminated polysulfide of said formula is reacted with a polyisocyanate at a ratio between about 1:1 and about 1:1.2 on an equivalents basis. The hydroxyl-terminated polysulfide is made by splitting a polysulfide having a molecular weight about 30 times greater in an aqueous latex dispersion with a dithiodialkylene glycol and sodium sulfite.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.