Moisture cured reactive hot melt adhesive with monofunctional reactants as grafting agents

• US 8,933,176 B2
• Filed: 09/01/2006
• Issued: 01/13/2015
• Est. Priority Date: 10/24/2002
• Status: Active Grant

• Current Assignee: Henkel AG & Co KGaA
• Original Assignee: Henkel AG & Co KGaA
• Inventors: Zhang, Yue S., Hung, Ju-Ming, Chu, Wayne K.
• Primary Examiner(s): Figueroa, John J
• Application Number:
  US11/514,499
• Publication Number:
  US 20070027272A1
• Time in Patent Office: 3,056 Days
• Field of Search: None
• US Class Current: 525/455
• CPC Class Codes: C08G 18/12 using two or more compounds having active hydrogen in the first polymerisation step
• CPC Class Codes: C08G 18/282 Alkanols, cycloalkanols or arylalkanols including terpenealcohols
• CPC Class Codes: C08G 18/307 Atmospheric humidity
• CPC Class Codes: C08G 18/4063 Mixtures of compounds of group C08G18/62 with other macromolecular compounds
• CPC Class Codes: C08G 2170/20 Compositions for hot melt adhesives
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]

Abstract

High green strength reactive hot melt adhesives are prepared using crystalline monofunctional reactants.

Claims

1. A reactive hot melt adhesive composition prepared from a mixture comprising one or more polyisocyanates;

one or more polyols, wherein no polyol is a crystalline polyol;

about 0.1 wt % to about 20 wt % of one or more crystalline monofunctional reactants; and

a functional thermoplastic polymer selected from acrylic polymers, functional acrylic polymers, hydroxy functional acrylic polymers, polyvinyl acetate, polyvinyl chloride, methylene polyvinyl ether, cellulose acetate, styrene acrylonitrile, amorphous polyolefin, thermoplastic urethane, polyacrylonitrile, polybutadiene, isobutylene diol and mixtures thereof;

wherein the adhesive composition does not include crystalline polyols.

2. The reactive hot melt composition of claim 1 wherein the mixture consists essentially of the one or more polyisocyanates, the one or more polyols, the about 0.1 wt % to about 20 wt % of one or more crystalline monofunctional reactants, and the functional thermoplastic polymer.

3. The reactive hot melt composition of claim 1 wherein the adhesive composition does not include polyester polyols.

4. The adhesive of claim 1 wherein the thermoplastic polymer is a mixture of two different thermoplastic polymers each independently selected from acrylic polymer, hydroxy functional acrylic polymer, polyvinyl acetate, methylene polyvinyl ether and polybutadiene.