Method for applying dispersion adhesives

Patent metadata

Field	Value
Publication number	US-10047253-B2
Application number	US-201415104307-A
Country	US
Kind code	B2
Filing date	Dec 15, 2014
Priority date	Dec 16, 2013
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

The invention relates to a method for applying dispersion adhesives containing one or more polyvinyl esters and optionally one or more additives, characterized in that one or more polyvinyl esters are produced by radical-initiated, continuous emulsion polymerization of a) one or more vinyl esters and, optionally, b) one or more additional ethylenically unsaturated monomers, and the dispersion adhesives are applied to a substrate by way of mechanical application methods.

First claim

The invention claimed is:

1. A method for applying dispersion-based adhesives comprising one or more polyvinyl esters, wherein
the one or more polyvinyl esters are prepared by radically initiated, continuous emulsion polymerization of one or more vinyl esters
by supplying a polymerization reactor or a reactor cascade continuously with said vinyl esters and continuously withdrawing a polymerization mixture from said reactor or reactor cascade, wherein
the polyvinyl esters have a polydispersity PD of ≥21, the polydispersity PD being the ratio of weight-average particle diameter Dw to number-average particle diameter Dn, PD=Dw/Dn, determined using a Beckmann Coulter LS instrument according to ISO 13320; and
the dispersion-based adhesives are applied to the substrate by machine application methods.

2. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein one or more polyvinyl esters are based on 50 to 90 wt % of the one or more vinyl esters, and 10 to 25 wt % of ethylene, based on the total weight of the monomers.

3. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the emulsion polymerization is carried out at a temperature of 40° C. to 100° C.

4. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the emulsion polymerization is carried out using 0.5 to 6.0 wt % of one or more polyvinyl alcohols having viscosities of 19 to 39 mPas as determined by the Höppler method according to DIN 53015 at 20° C. in 4% strength aqueous solution.

5. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the dispersion-based adhesives are free from emulsifiers.

6. The method for applying dispersion-based adhesives as claimed in claim 5 , wherein the average residence time in the polymerization reactor or in the pressure reactor cascade is 60 to 240 minutes.

7. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the machine application methods are selected from the group consisting of nozzle application methods and roll application methods.

8. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the substrate is selected from the group consisting of paper and plastics.

9. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein a reactor cascade is continuously supplied with said vinyl esters.

10. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the emulsion polymerization takes place in the presence of at least one medium-viscosity polyvinyl alcohol having a viscosity of 19 to 39 mPas and of at least one high-viscosity polyvinyl alcohol having a viscosity of 40 to 60 mPas.

11. The method for applying dispersion-based adhesives as claimed in claim 1 , wherein the emulsion polymerization is carried out at a temperature of 50° C. to 100° C.

Assignees

• Wacker Chemie Ag

Inventors

• Babar Muhammad
• Kögler Gerhard
• Weitzel Hans-Peter

Classifications

• C08L29/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title

• C09J131/04 Primary

  Homopolymers or copolymers of vinyl acetate · CPC title

• C09J5/00

  Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers · CPC title

• C09J2431/00

  Presence of polyvinyl acetate · CPC title