Skinned Substrates with Highly Crosslinked Polyurethane Layer

Patent metadata

Field	Value
Publication number	US-2016016379-A1
Application number	US-201314410090-A
Country	US
Kind code	A1
Filing date	Jun 20, 2013
Priority date	Jun 27, 2012
Publication date	Jan 21, 2016
Grant date	—

Abstract

PVC-skinned composites include a substrate, a skin and an intermediate polyurethane layer. The polyurethane layer is characterized in having a low molecular weight between crosslinks, i.e., is somewhat highly crosslinked. The high level of crosslinking in the polyurethane leads to improved performance of the skin layer. The skin layer retains its original color upon aging, is less prone to shrinking and other loss of physical properties, and adheres better to the polyurethane layer.

First claim

1 . A skinned composite comprising
a) a substrate, b) an exterior plasticized polymeric skin covering at least a portion of the substrate; and c) a polyurethane layer interposed between the substrate and the plasticized polymeric skin, wherein the polyurethane layer is the reaction product of a reaction mixture that contains one or more polyisocyanates and one or more isocyanate-reactive compounds that contain two or more isocyanate-reactive groups, wherein the polyurethane has a calculated molecular weight per crosslink of no greater than 1250 as calculated by the formula

MW
xl

=

A
+
B

A


(

C
-
2

)

CD

+

B


(

F
-
2

)

EFG

+

B


(

F
-
1

)



(

1
-

1
E

)

(

E
+
1

)


G

wherein
A is the combined weight, in grams, of all isocyanate-reactive materials that contain at least 2 isocyanate-reactive groups/molecule, including any water, provided to the reaction mixture;
B is the combined weight, in grams, of all isocyanate compounds provided to the reaction mixture;
C is average functionality of all isocyanate-reactive compounds provided to the reaction mixture that contain at least 2 isocyanate-reactive groups/molecule, including any water;
D is the average equivalent weight in grams per hydroxyl group of all isocyanate-reactive compounds provided to the reaction mixture that contain at least 2 isocyanate-reactive groups/molecule, including any water;
E is the isocyanate index, calculated as the number of equivalents of isocyanate groups provided to the reaction mixture divided by the number of equivalents of isocyanate-reactive groups provided to the reaction mixture;
F is the average functionality of all isocyanate compounds provided to the reaction mixture; and
G is the average equivalent weight in grams per isocyanate group of all isocyanate compounds provided to the reaction mixture.

2 . A skinned composite comprising
a) a substrate, b) an exterior plasticized polymeric skin covering at least a portion of the substrate; and c) a polyurethane layer interposed between the substrate and the plasticized polymeric skin, wherein the polyurethane layer is the reaction product of a reaction mixture that contains one or more polyisocyanates and one or more isocyanate-reactive compounds that contain two or more isocyanate-reactive groups, wherein the isocyanate index is from 0.9 to 1.25 and the isocyanate-reactive compounds that contain two or more isocyanate-reactive groups are selected from the group consisting of: 1) a blend of a high functionality polyol having a hydroxyl functionality of at least 4, and a hydroxyl equivalent weight of 80 to 250 with at least one low equivalent weight polyol, aminoalcohol or polyamine that has an equivalent weight per isocyanate group of up to about 125, more preferably up to 75, and a functionality of 3 to 4; 2) a blend of a high functionality polyol having a hydroxyl functionality of at least 4, and a hydroxyl equivalent weight of 80 to 250 with one or more high equivalent weight polyether polyols or polyether amines, the high equivalent weight polyol or polyether amine having a functionality of 2 to 3 and an equivalent weight of at least 350 to 2200; 3) a blend of a high functionality polyol having a hydroxyl functionality of at least 4, and a hydroxyl equivalent weight of 80 to 250 with at least one low equivalent weight polyol, aminoalcohol or polyamine that has an equivalent weight per isocyanate group of up to about 125, more preferably up to 75, and a functionality of 3 to 4 and one or more high equivalent weight polyols or polyether amines having a functionality of 2 to 3 and an equivalent weight of at least 350 to 2200; 4) a blend as in any of 1)-3), further including water; and 5) a blend as in any of 1)-4), further including one or more aliphatic polyesters having a hydroxyl functionality of at least 2 and a hydroxyl equivalent weight of about 350 to 1500 and which are a reaction product of an aliphatic dicarboxylic acid (or corresponding acid chloride or diester) with at least one polyol having at least 2 hydroxyl groups and a hydroxyl equivalent weight of 150 or less, or a mixture of such a polyol with one or more diols having a hydroxyl equivalent weight of 150 or less.

3 . The skinned composite of claim 1 wherein the skin is a plasticized thermoplastic.

4 . The skinned composite of claim 3 wherein the skin is a plasticized polymer of vinyl chloride.

5 . The skinned composite of claim 4 wherein the skin contains 25 to 40% by weight of a plasticizer.

6 . The skinned composite of claim 1 , wherein the density of the polyurethane layer is from 48 to 480 kg/m 3 .

7 . The skinned composite of claim 1 wherein the polyisocyanate(s) have an average functionality of at least 2.0 and an isocyanate equivalent weight of 85-200.

8 . A method for preparing the skinned composite of claim 1 , comprising positioning the skin and substrate within a mold to form a gap between the skin and substrate, introducing the reaction mixture into the mold between the skin and substrate and curing the reaction mixture in the mold between the skin and substrate.

9 . The skinned composite of claim 2 wherein the skin is a plasticized thermoplastic.

10 . The skinned composite of claim 9 wherein the skin is a plasticized polymer of vinyl chloride.

11 . The skinned composite of claim 10 wherein the skin contains 25 to 40% by weight of a plasticizer.

12 . The skinned composite of c

Assignees

• Dow Global Technologies Llc

Inventors

• Cavalca Sara
• Fregni Sabrina

Classifications

• B32B27/22

  using plasticisers · CPC title

• B32B27/065

  of foam · CPC title

• B29C44/1233

  the preformed parts being supported during expanding · CPC title

• B29K2075/00

  Use of {PU, i.e.} polyureas or polyurethanes {or derivatives thereof}, as moulding material · CPC title

• C08J9/35

  Composite foams, i.e. continuous macromolecular foams containing discontinuous cellular particles or fragments · CPC title