Acrylic polyvinyl acetal films & composition

Patent metadata

Field	Value
Publication number	US-2016289440-A1
Application number	US-201615175458-A
Country	US
Kind code	A1
Filing date	Jun 7, 2016
Priority date	Dec 8, 2014
Publication date	Oct 6, 2016
Grant date	—

Abstract

A film is described comprising a (meth)acrylic polymer and a polyvinyl acetal (e.g. butyral) resin. In some embodiments, the film has a glass transition temperature (i.e. Tg) ranging from 30° C. to 60° C. In some embodiments, the film has a gel content of at least 20% or greater. In some embodiments, the film has an elongation at break of at least 175%. The film typically comprises photoinitiator as a result of the method by which the film was made. The film may be a monolithic film or a layer of a multilayer film.

First claim

What is claimed is:

1 . A film comprising:
a single phase of (meth)acrylic polymer and polyvinyl acetal resin comprising polymerized units having the following formula

wherein R 1 is hydrogen or a C1-C7 alkyl group;
wherein the film has a Tg ranging from 30° C. to 60° C.

2 . The film of claim 1 wherein the film comprises at least 10, 15, 20 or 25 wt-% of polymerized units of monofunctional alkyl (meth)acrylate monomer having a Tg of less than 0° C.

3 . The film of claim 2 wherein the film comprises no greater than 60 wt-% of polymerized units of monofunctional alkyl (meth)acrylate monomer having a Tg of less than 0° C.

4 . The film of claim 2 or 3 wherein the monofunctional alkyl (meth)acrylate monomer has a Tg of less than −10° C., −20° C., −30° C., or −40° C.

5 . The film of claims 1 - 4 wherein the film comprises a bio-based content of at least 10, 15, 20 or 25% of the total carbon content.

6 . The film of claims 1 - 5 wherein the film comprises polymerized units of an alkyl (meth)acrylate monomer having an alkyl group with 8 carbon atoms.

7 . The film of claims 1 - 6 wherein the film further comprises up to 35 wt-% of polymerized units of a monofunctional alkyl (meth)acrylate monomer having a Tg greater than 40° C., 50° C., 60° C., 70° C., or 80° C.

8 . The film of claims 1 - 7 wherein the film further comprises at least 10, 15 or 20 wt-% and no greater than 65 wt-% of polymerized units of polar monomers.

9 . The film of claim 8 wherein polar monomers are selected from acid-functional, hydroxyl functional monomers, nitrogen-containing monomers, and combinations thereof.

10 . The film of claims 1 - 9 wherein the film comprises polyvinyl butyral.

11 . The film of claims 1 - 10 wherein the film comprises 5 to 30 wt-% of polyvinyl acetal resin.

12 . The film of claims 1 - 11 wherein the polyvinyl acetal resin has a polyvinyl alcohol content ranging from 10 to 30.

13 . The film of claims 1 - 12 wherein the polyvinyl acetal resin has a glass transition temperature ranging from 60° C. to 75° C.

14 . The film of claims 1 - 13 wherein the polyacetal resin has an average molecular weight (Mw) ranging from 20,000 g/mole to 75,000 g/mole.

15 . The film of claims 1 - 14 wherein the film further comprises polymerized units of a multifunctional crosslinker wherein the crosslinker comprises functional groups selected from (meth)acrylate, alkenyl, and hydroxyl-reactive groups.

16 . The film of claims 1 - 15 wherein the film further comprises additives in an amount no greater than 25 wt-%.

17 . The film composition of claims 1 - 16 wherein the film composition comprises photoinitiator.

18 . The film composition of claims 1 - 17 wherein the film comprises no greater than 10 wt-% of polymerized units of methacrylate monomers.

19 . The film composition of claims 1 - 18 wherein the (meth)acrylic polymer is a random copolymer.

20 . The film of claims 1 - 19 wherein the film is a monolithic film.

21 . The film of claims 1 - 19 wherein the film is a film layer of a multilayer film.

22 . The film of claim 21 wherein the multilayer film further comprises a second film layer, the second film layer comprising a (meth)acrylic polymer and polyvinyl acetal resin wherein the second film layer has a Tg of less than 30° C.

23 . The film of claim 22 wherein the second film layer is heat bondable.

24 . A film comprising:
a single phase of (meth)acrylic polymer and polyvinyl acetal resin comprising polymerized units having the following formula

wherein R 1 is hydrogen or a C1-C7 alkyl group;
wherein the film has a gel content of at least 20%.

25 . The film of claim 24 wherein the film has a Tg ranging from 30° C. to 60° C.

26 . The film of claims 1 - 25 wherein the film has an elongation at break of at least 175%.

Assignees

• 3M Innovative Properties Co

Inventors

• Janoski Jonathan E
• Schultz Anthony F
• Lyon Keith R
• Steelman Ronald S
• Lewandowski Kevin M
• Lipscomb Corinne E
• Hobbs Terry R
• Weikel Arlin L
• Seth Jayshree
• Fansler Duane D
• Abe Hidetoshi

Classifications

• C09J133/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C09J7/025

  Chemistry & Metallurgy · mapped topic

• C08L33/08 Primary

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C09D133/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08L2203/16

  used for films · CPC title