Moisture-curable hot melt adhesive

Patent metadata

Field	Value
Publication number	US-11236257-B2
Application number	US-201816013198-A
Country	US
Kind code	B2
Filing date	Jun 20, 2018
Priority date	Dec 25, 2015
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

The object of the present invention is to provide a moisture-curable hot melt adhesive having high initial adhesive strength, long open time, excellent coating property and reduced stringing property. The present invention relates to a moisture-curable hot melt adhesive comprising (A) a urethane prepolymer having a terminal isocyanate group, (B) a metallocene-based polyolefin having a viscosity of 10,000 mPa·s or less at a temperature of 170° C. and (C) a polyester-polyether copolymer.

First claim

The invention claimed is:

1. A moisture-curable hot melt adhesive comprising, based on 100 parts by total weight of adhesive:
(A) 20 to 50 parts by weight of a urethane prepolymer having a terminal isocyanate group, the urethane prepolymer being a reaction product of a mixture comprising a polyisocyanate, a polyether polyol and a polyester polyol,
(B) 2 to 15 parts by weight of a metallocene-based polyolefin having a viscosity of 10,000 mPa·s or less at a temperature of 170° C., and
(C) 2 to 20 parts by weight of a polyester-polyether block copolymer comprising a polybutylene terephthalate segment; and a segment selected from polytetramethylene glycol, and
(D) 4 to 12 parts by weight of an ethylene/carboxylic acid ester copolymer comprising an ethylene vinyl acetate copolymer.

2. The moisture-curable hot melt adhesive according to the above claim 1 , wherein the content of vinyl acetate in the ethylene/vinyl acetate copolymer is 20 to 50% by weight.

3. The moisture-curable hot melt adhesive according to the above claim 1 , wherein the melt flow rate of the ethylene/vinyl acetate copolymer (D) is 20 to 200 g/10 min at 190° C., 2.16 kg.

4. The moisture-curable hot melt adhesive according to claim 1 , further comprising (E) an α-methyl styrene-based resin.

5. The moisture-curable hot melt adhesive according to claim 4 , comprising 2 to 15 parts by weight of the metallocene-based polyolefin (B) based on 100 parts by weight of a total weight of (A), (B), (C) and (E).

6. A laminate comprising the moisture-curable hot melt adhesive according to claim 1 .

7. Cured reaction products of the moisture-curable hot melt adhesive according to claim 1 .

8. A method for producing a moisture-curable hot melt adhesive according to claim 1 comprising:
reacting a polyol and an isocyanate compound to form (A) a urethane prepolymer having a terminal isocyanate group;
providing (B) a metallocene-based polyolefin, (C) a polyester-polyether copolymer, (D) an ethylene/carboxylic acid ester copolymer, and (E) an α-methyl styrene-based resin; and
mixing the (A) a urethane prepolymer, (B) the metallocene-based polyolefin, (C) the polyester-polyether copolymer, (D) the ethylene/carboxylic acid ester copolymer, and (E) the α-methyl styrene-based resin to form the moisture-curable hot melt adhesive.

9. The moisture-curable hot melt adhesive according to claim 1 , wherein the ethylene/carboxylic acid ester copolymer (D) comprises an ethylene-C 1-10 alkyl (meth)acrylate copolymer.

10. The moisture-curable hot melt adhesive according to claim 1 , wherein the ethylene/carboxylic acid ester copolymer (D) comprises the ethylene/vinyl acetate copolymer and an ethylene-C 1-10 alkyl (meth)acrylate copolymer.

11. The moisture-curable hot melt adhesive according to claim 1 , comprising:
30 to 40 parts by weight of the (A) urethane prepolymer;
4 to 12 parts by weight of the (B) metallocene-based polyolefin;
5 to 15 parts by weight of the (C) polyester-polyether copolymer;
wherein the total weight of all components in the moisture curable hot melt adhesive is 100.

12. A moisture-curable hot melt adhesive comprising, based on 100 parts by total weight of adhesive:
(A) 20 to 50 parts by weight of a urethane prepolymer having a terminal isocyanate group, the urethane prepolymer being a reaction product of a mixture comprising a polyisocyanate, a polyether polyol and a polyester polyol,
(B) 2 to 15 parts by weight of a metallocene-based polyolefin having a viscosity of 10,000 mPa·s or less at a temperature of 170° C., and
(C) to 20 parts by weight of a polyester-polyether copolymer having a chemical structure comprising

wherein n denotes an integer and is preferably 20 to 1,000; and

wherein p is an integer of 2 to 5, q is an integer of 2 to 200, and m is an integer of 1 to 200, and
(D) 4 to 12 parts by weight of an ethylene/carboxylic acid ester copolymer.

13. The moisture-curable hot melt adhesive according to claim 1 , wherein the urethane prepolymer mixture comprises an amount of the polyether polyol and a greater amount of polyester polyol, the amounts in parts by weight of the mixture.

Assignees

• Henkel Ag & Co Kgaa

Inventors

• Matsuda Kenji
• Takamori Ai
• Tamogami Tsuyoshi

Classifications

• C09J125/16 Primary

  Homopolymers or copolymers of alkyl-substituted styrenes · CPC title

• C08L23/02

  not modified by chemical after-treatment · CPC title

• B32B21/04

  comprising wood as the main or only constituent of a layer, {which is} next to another layer of {the same or of} a {different material (next to a layer of a particular substance B32B9/042; next to a bituminous or tarry layer B32B11/042; next to a water setting substance layer B32B13/10; next to a metal layer B32B15/10; next to a glass layer B32B17/062; next to a layer formed of natural mineral fibres or particles B32B19/042; next to a cellulosic plastic layer B32B23/044)} · CPC title

• B32B2457/00

  Electrical equipment · CPC title

• C08L23/04

  Homopolymers or copolymers of ethene · CPC title