Bituminous polyurethane interpenetrating elastomeric network compositions as coatings and sealants for roofing and other applications
AssigneeUrecoats International, Inc.
InventorsPonswamy Rajalingam, Umarani Rajalingam
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Abstract
Elastomeric polyurethane interpenetrating network compositions are disclosed which are preferably developed by in situ reaction of polyols with different isocyanates and polyisocyanates in a bituminous material, such as, asphalt, coal tar, polymer modified asphalt, oxidized, and unoxidized asphalt. The composition is preferably formed at a temperature between 200° F. and 350° F. The reaction kinetics can be accelerated by including catalysts and curing agents. Bituminous polyurethane interpenetrating network elastomers are suitable for a wide variety of applications including but not limited to roofing, new construction, and wall and foundation waterproofing applications.
Claims33
A bituminous polyurethane interpenetrating elastomeric composition comprising:
- a bituminous material;
- a polyol;
- a curing agent chosen from a group consisting of polyoxy(methyl-1,2,-ethanediol), alpha-hyrdoxyomega-(2-aminomethylethoxy) -ether with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (3:1);
- diethyltoluenediamine;
- di-(methylthio) toluenediamine;
- 1,6-hexamethylene diamine;
- trimethylol propane;
- 3,5-dimethylthio-2,6-toluenediamine;
- and 3,5-dimethylthio-2,4-toluenediamine;
- and
- an isocyanate.
A bituminous polyurethane interpenetrating elastomeric network composition comprising:
- fifty percent by weight of rubberized asphalt;
- thirty-six percent by weight of a polyol;
- four percent by weight of a curing agent blend consisting essentially of 3,5-dimethylthio-2,6-toluenediamine and 3,5- dimethylthio-2,4-toluenediamine;
- a trace amount of dibutyltin dilaurate;
- and
- ten percent by weight of diphenylmethane diisocyanate.
An in situ polymerization method of preparing a bituminous polyurethane interpenetrating elastomeric network composition comprising a bituminous material, a polyol blend having a polyol and a curing agent, and an isocyanate;
- said method comprising the steps of:
- heating said bituminous material in a first container at least to its molten temperature,
- providing said polyol blend in a second container,
- mixing said heated bituminous material and said polyol blend together to form a reagent mixture,
- adding said isocyanate to said reagent mixture immediately before application to a surface to form in situ said bituminous polyurethane interpenetrating elastomeric network composition, and
- allowing said composition to cure after it is applied to a surface.
A bituminous polyurethane interpenetrating elastomeric network composition comprising a rubberized oxidized asphalt, a polyol, an asphalt soluble curing agent and an isocyanate;
- said composition made through a method comprising the steps of:
- heating said rubberized oxidized asphalt in a first container at least to its molten temperature,
- mixing said polyol having said asphalt soluble curing agent added thereto to form a polyol blend in a second container,
- mixing said rubberized oxidized asphalt and said polyol blend together to form a reagent mixture, and
- adding said isocyanate to said reagent mixture immediately before application to a surface to provide for an in situ formation of a bituminous polyurethane interpenetrating elastomeric network composition which is allowed to cure after application to the surface.
A method of preparing a bituminous polyurethane interpenetrating elastomeric network composition comprising a rubberized asphalt, a polyol blend of polyol and a curing agent, a catalyst and an isocyanate, said method comprising the steps of:
- (a) heating a rubber mix at least to the molten temperature of the asphalt;
- (b) providing a polyol;
- (c) adding an aromatic curing agent as a compatabilizer for the asphalt and the polyol;
- (d) adding a catalyst to the polyol to accelerate the polyurethane formation kinetics;
- (e) mixing an isocyanate with the heated rubberized asphalt and polyol immediately before spray application of the composition on substrates;
- and
- (f) allowing said composition to fully cure after it is spray applied the composition on a final substrate.
A bituminous polyurethane interpenetrating elastomeric composition comprising:
- a hot melt crumb rubber modified oxidized asphalt,
- a polyol,
- an isocyanate;
- and
- a curing agent for allowing the composition of crumb rubber modified oxidized rubberized asphalt, polyol and isocyanate to cure;
- wherein said crumb rubber modified oxidized asphalt increases the polarity of the asphalt for increased compatibility and reaction between the asphalt and said isocyanate;
- wherein said curing agent is added to said polyol to form a polyol blend prior to mixing said polyol blend with said hot melt crumb rubber modified oxidized asphalt;
- wherein the mixing of said polyol blend with said crumb rubber modified oxidized asphalt yields a reagent mixture;
- wherein said reagent mixture is mixed with the isocyanate through an in situ hot melt polymerization reaction;
- wherein said catalyst, said rubberized modified oxidized asphalt, the polyol and said isocyanate form a formulation which is fully cured after the formulation is spray applied to a surface.
An in situ polymerization method of preparing a bituminous polyurethane interpenetrating elastomeric network composition comprising a bituminous material including rubber modified oxidized asphalt, a polyol blend having a polyol and a curing agent blend consisting of 3,5-dimethylthio-2,6- toluenediamine and 3,5-dimethylthio-2,4-toluenediamine, and an isocyanate;
- said method comprising the steps of:
- heating said bituminous material in a first container at least to its molten temperature,
- providing said polyol blend in a second container,
- mixing said heated bituminous material and said polyol blend together to form a reagent mixture, and
- adding said isocyanate to said reagent mixture immediately before application to a surface to form in situ said bituminous polyurethane interpenetrating elastomeric network composition.
A bituminous polyurethane interpenetrating elastomeric network composition comprising:
- a rubberized asphalt;
- a polyol;
- a curing agent blend consisting essentially of 3,5- dimethylthio-2,6-toluenediamine and 3,5-dimethylthio-2,4- toluenediamine;
- dibutyltin dilaurate;
- and
- diphenylmethane diisocyanate.
Dependencies are inferred from the claim text.