Packaged viscoelastic polymer substance

Patent metadata

Field	Value
Publication number	US-2022010177-A1
Application number	US-201917293652-A
Country	US
Kind code	A1
Filing date	Nov 13, 2019
Priority date	Nov 13, 2018
Publication date	Jan 13, 2022
Grant date	—

Abstract

Packaged viscoelastic polymer substances and methods for the production of the packaged viscoelastic polymer substances are provided. The packaged viscoelastic polymer substances are further processable under the influence of heat and shear.

First claim

1 . A method for producing a packaged viscoelastic polymer substance, the method comprising:
a) plastifying a viscoelastic polymer substance at elevated temperatures, the viscoelastic polymer substance being a polymer substance based on poly(meth)acrylates having a weight-average molecular weight of 500,000 g/mol or more; b) continuously dispensing the plastified viscoelastic polymer substance into a protective polymer film, that has no self-adhesive properties and which, before being filled with the plastified viscoelastic polymer substance, has been brought into a tubular form, to give a strandlike polymer assembly having a diameter of 55 to 70 mm, a core of the plastified viscoelastic polymer substance, and a shell of the protective polymer film, wherein a fraction of the protective polymer film, based on a total weight of the protective polymer film and the plastified viscoelastic polymer substance, is less than 1.0 wt %, and wherein where the plastified viscoelastic polymer substance has a viscosity of more than 100 Pas at the instant of being dispensed into the tubular protective polymer film; c) converting the strandlike polymer assembly into a flattened strandlike polymer assembly with a smallest cross-section having a ratio of width to height of about 2:1 to 7:1; d) cooling the flattened strandlike polymer assembly to a temperature at which the strandlike polymer assembly is still plastically deformable; and e) subsequently converting the flattened strandlike polymer assembly by squeezing into an elongate polymer assembly comprising a multiplicity of squeeze points, that subdivide the polymer assembly into a multiplicity of first regions and a multiplicity of second regions, wherein each of the first regions have a length of at least about 300 mm and a cross-section of the first regions corresponds substantially to a cross-section of the strandlike polymer assembly, wherein the second regions are formed by the squeeze points, with thicknesses resulting from thicknesses of the protective polymer film and the viscoelastic polymer substance that remains in regions of the squeeze points, and wherein the second regions have a length corresponding to once to twice a maximum extent along the cross-section of the first regions.

2 . The method of claim 1 , wherein the converting of the strandlike polymer assembly into the flattened strandlike polymer assembly in c) is carried out by means of rolls.

3 . The method of claim 1 , wherein the cooling in d) is carried out down to a core temperature of less than 100° C.

4 . The method of claim 1 , wherein the strandlike polymer assembly after e) is deposited in a container, wherein a direction of deposition of the elongate polymer assembly changes at the squeeze points.

5 . The method of claim 1 , wherein d) takes place in a water bath.

6 . The method of claim 1 , wherein the plastifying in a) is carried out in an extruder.

7 . The method of claim 1 , wherein the plastified viscoelastic polymer substance has a viscosity of more than 250 Pas at the instant of being dispensed into the protective polymer film.

8 . The method of claim 1 , wherein the fraction of the protective polymer film in b), based on the total weight of the protective polymer film and plastified viscoelastic polymer substance, is less than 0.5 wt %.

9 . The method of claim 1 , wherein the protective polymer film consists of polyethylene, polypropylene, ethylene-vinyl acetate, or a mixture thereof.

10 . The method of claim 1 , wherein the viscoelastic polymer substance is a self-adhesive substance or is convertible into a self-adhesive substance.

11 . The method of claim 1 , wherein the viscoelastic polymer substance has a density at 25° C. of 1.05 to 1.3 g/cm 3 .

12 . A packaged viscoelastic polymer substance obtainable by the method of claim 1 .

13 . A method comprising:
plastifying the packaged viscoelastic polymer substance of claim 12 under the influence of heat and shear.

14 . The method of claim 13 , further comprising:
treating the treatment of the packaged viscoelastic polymer substance with heat and shear for further processing such that the protective polymer film is plastified.

15 . The method of claim 13 , wherein the treatment with heat and shear is carried in an extruder.

Assignees

• Tesa Se

Inventors

• Massow Klaus
• Lass Volker
• Brandes Kay

Classifications

• C09J133/08 Primary

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C09J2423/046

  in the substrate · CPC title

• C09J7/243

  Ethylene or propylene polymers · CPC title

• B65B9/20

  the webs being formed into tubes in situ around the filling nozzles · CPC title

• B65B61/24

  for shaping or reshaping completed packages · CPC title