阅读说明：本技术 用于保水应用的亲水性聚氨酯泡沫 (Hydrophilic polyurethane foams for water retention applications ) 是由 C·舍恩内 Y·N·斯里瓦斯塔瓦 于 2019-09-17 设计创作，主要内容包括：公开了一种亲水性聚氨酯泡沫,所述亲水性聚氨酯泡沫从具有指定异氰酸酯和氧乙烯含量的基于二苯甲烷的准预聚物产生。所述泡沫具有异常良好的保水能力,即使在压缩力下也如此。以水饱和时,它们也显示出至多中等的溶胀。所述泡沫可用作水容纳系统(如绿色屋面或蓝色屋面系统)的层。(Disclosed is a hydrophilic polyurethane foam produced from a diphenylmethane-based quasi-prepolymer having a specified isocyanate and oxyethylene content. The foam has exceptionally good water retention even under compressive forces. They also show at most moderate swelling upon saturation with water. The foam may be used as a layer of a water containment system, such as a green or blue roofing system.)

1. A hydrophilic polyurethane foam which is the reaction product of a reaction mixture comprising:

a) the amount of water is controlled by the amount of water,

b) a quasi-prepolymer having an isocyanate content of from 5% to 15% by weight and containing from 55 to 75 weight percent of oxyethylene units based on the weight of the quasi-prepolymer, the quasi-prepolymer being the reaction product of: i) a hydroxyl terminated ethylene oxide polymer or a mixture of two or more thereof, wherein the hydroxyl terminated ethylene oxide polymer or mixture thereof has an average oxyethylene content of at least 90 weight percent, has a number average nominal hydroxyl functionality of from 2 to 2.5, and has a number average hydroxyl equivalent weight of at least 350, based on the weight of the hydroxyl terminated ethylene oxide polymer or mixture thereof; and ii) an excess of an organic polyisocyanate comprising at least 80 weight percent of diphenylmethane diisocyanate, wherein at least 60 weight percent of the diphenylmethane diisocyanate is 4,4' -diphenylmethane diisocyanate, wherein component b) is present in an amount sufficient to provide an isocyanate index of from 0.5 to 50; and

c) one or more surfactants.

2. The hydrophilic polyurethane foam of claim 1 wherein the hydroxyl terminated ethylene oxide polymer or a mixture of two or more thereof comprises at least one ethylene oxide homopolymer.

3. The hydrophilic polyurethane foam according to claim 1 or 2, wherein the hydroxyl-terminated ethylene oxide polymer or a mixture of two or more thereof comprises at least one random or block copolymer of ethylene oxide and 1, 2-propylene oxide containing from 50 to 95 weight percent of oxyethylene groups and correspondingly containing from 5 to 50 weight percent of 2-methoxypropene groups.

4. A method of producing a hydrophilic polyurethane foam, the method comprising:

A. forming a reaction mixture comprising:

a) the amount of water is controlled by the amount of water,

b) a quasi-prepolymer having an isocyanate content of from 5% to 15% by weight and containing from 55 to 75 weight percent of oxyethylene units based on the weight of the quasi-prepolymer, the quasi-prepolymer being the reaction product of: i) a hydroxyl terminated ethylene oxide polymer or a mixture of two or more thereof, wherein the hydroxyl terminated ethylene oxide polymer or mixture thereof has an average oxyethylene content of at least 90 weight percent and has a number average hydroxyl equivalent weight of at least 350 based on the weight of the one or more hydroxyl terminated ethylene oxide polymers or mixtures thereof; and ii) an excess of an organic polyisocyanate comprising at least 80 weight percent of diphenylmethane diisocyanate, wherein at least 60 weight percent of the diphenylmethane diisocyanate is 4,4' -diphenylmethane diisocyanate, wherein component b) is present in an amount sufficient to provide an isocyanate index of from 0.5 to 50; and

c) one or more surfactants; and

B. curing the reaction mixture formed in step a.

5. The method of claim 4 wherein the hydroxyl terminated ethylene oxide polymer or mixture of two or more thereof comprises at least one ethylene oxide homopolymer.

6. The method of claim 4 or 5, wherein the hydroxyl-terminated ethylene oxide polymer, or a mixture of two or more thereof, comprises at least one random or block copolymer of ethylene oxide and 1, 2-propylene oxide containing from 50 to 95 weight percent oxyethylene groups and correspondingly containing from 5 to 50 weight percent 2-methoxypropene groups.

7. The method of any one of claims 4-6, wherein the reaction mixture is characterized as having an isocyanate index of 2 to 25 and a water index of 400 to 12,000.

8. A water containment system comprising a hydrophilic polyurethane foam according to any one of claims 1-3 and/or produced according to the method of any one of claims 4-7.

9. A water containment system comprising at least one water barrier layer; at least one layer of a hydrophilic polyurethane foam produced according to any one of claims 1-3 and/or according to the method of any one of claims 4-7, directly or indirectly on top of at least a portion of the water barrier layer; and at least one top surface layer directly or indirectly on top of at least a portion of the hydrophilic foam layer; the water containment system includes a drainage device for draining water falling on the top surface layer to the hydrophilic foam layer.

10. The water containment system of claim 9, wherein said top surface layer comprises a soil layer and a vegetation layer, and said drainage means comprises an aperture in said soil layer in fluid communication with said hydrophilic foam layer.

11. The water containment system of claim 9 or 10, wherein the hydrophilic polyurethane foam layer has one or more channels on a bottom surface that form a path through which water may flow and be removed from the water containment system.

12. The water containment system according to any one of claims 9-11, further comprising a roofing structure directly or indirectly below the water barrier layer.

13. A quasi-prepolymer having an isocyanate content of 5 to 15 weight percent and containing 55 to 75 weight percent oxyethylene units based on the weight of the quasi-prepolymer, the quasi-prepolymer being the reaction product of: i) a hydroxyl terminated ethylene oxide polymer or a mixture of two or more thereof, wherein the hydroxyl terminated ethylene oxide polymer or mixture thereof has an average oxyethylene content of at least 90% and has a number average hydroxyl equivalent weight of at least 350, based on the weight of the one or more hydroxyl terminated ethylene oxide polymers or mixtures thereof; and ii) an excess of an organic polyisocyanate comprising at least 80 weight percent of diphenylmethane diisocyanate, wherein at least 60 weight percent of the diphenylmethane diisocyanate is 4,4' -diphenylmethane diisocyanate.