Impact-reinforced acrylic material

Patent metadata

Field	Value
Publication number	US-9546268-B2
Application number	US-201214009346-A
Country	US
Kind code	B2
Filing date	Apr 5, 2012
Priority date	Apr 7, 2011
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

The subject of the present invention is a semi-rigid or flexible and low-gloss impact-reinforced acrylic material. The acrylic material according to the invention comprises a nanostructured matrix constituted of at least one thermoplastic acrylic block copolymer and at least one highly crosslinked acrylic copolymer. The matrix comprises at least one thermoplastic acrylic block copolymer. The highly crosslinked acrylic copolymer comprises, as sole monomer or as predominate monomer, MMA, that is to say that it comprises, by weight, more than 50%, advantageously more than 65% of MMA. The acrylic material according to the invention comprises from 60% to 99% by weight of matrix for 40% to 1% by weight of crosslinked copolymer. These materials may be converted by injection molding, extrusion, co-extrusion, extrusion-blow molding for producing parts, profiles, sheets or films for example.

First claim

The invention claimed is:

1. An acrylic material comprising:
a matrix composed of at least one nanostructured thermoplastic acrylic block copolymer, having a general formula (A) n B in which:
n is an integer of greater than or equal to 1,
A is: an acrylic or methacrylic homo- or copolymer having a Tg of greater than 50° C., polystyrene, an acrylic/styrene copolymer or methacrylic/styrene copolymer,
B is an acrylic or methacrylic homo- or copolymer having a Tg of less than 20° C.

and at least one highly crosslinked acrylic copolymer.

2. The material as claimed in claim 1 , additionally comprising an inorganic filler chosen from silica, talc, kaolin, calcium carbonate, carbon black, titanium oxides and pigments.

3. The material as claimed in claim 1 comprising, by weight, from 60% to 99% of matrix for from 40% to 1% of highly crosslinked copolymer.

4. The material as claimed in claim 1 , in which the block A is polymethyl methacrylate, polyphenyl methacrylate, benzyl polybenzyl methacrylate or polyisobronyl methacrylate.

5. The material as claimed in claim 1 , in which the block A is polymethylmethacrylate (PMMA) or PMMA modified with acrylic or methacrylic comonomers.

6. The material as claimed in claim 1 , in which said matrix comprises, in addition to the thermoplastic acrylic block copolymer, at least one other thermoplastic polymer chosen from PMMAs, acrylonitile/butadiene/styrene (ABS) and thermoplastic polyurethane (TPU).

7. The material as claimed in claim 1 , in which the thermoplastic acrylic block copolymer is chosen from the following triblock copolymers: polymethyl methacrylate/polybutyl acrylate/polymethyl methacrylate (pMMA-pBuA-pMMA), poly(methyl methacrylate-co-methacrylic acid)/polybutyl acrylate/poly(methyl methacrylate-co-methacrylic acid) (p(MMAcoMAA)-pBuA-p(MMAcoMAA)) and poly(methyl methacrylate-co-acrylic acid)/polybutyl acrylate/poly(methyl methacrylate-co-acrylic acid) (p(MMAcoAA)-pBuA-p(MMAcoAA)).

8. The material as claimed in claim 7 , additionally comprising at least one acrylic polymer additive consisting of from 20% to 80% of methyl (MMA), from 20% to 80% of butyl methacrylate (BMA) and from 0% to 15% of methacrylic acid (MAA) or acrylic acid (AA), and having a weight-average molecular weight of between 40 000 and 100 000 g/mol.

9. The material as claimed in claim 8 , consisting, by weight, of 5% to 40% of acrylic copolymer, from 3% to 30% of highly crosslinked acrylic copolymer and for from 92% to 30% of nanostructured matrix.

10. The material as claimed in claim 7 , in which said at least one highly crosslinked acrylic copolymer consists of particles of polymers having a mean size of between 10 and 70 microns and comprising by weight: 99.9%-50% of MMA, 0%-50% of comonomer which can copolymerize by the radical route with the MMA and 0.1%-2.5% of crosslinking agent.

11. The material as claimed in claim 10 , exhibiting a gloss of less than 20 measured under an angle of 60°.

12. The material as claimed in claim 10 , exhibiting a flexural modulus ranging from 500 MPa to less than 1800 MPa and a notched Charpy impact strength of at least 6 kJ/m 2 , as measured according to the standard EN ISO 179-1 at 23° C.

13. The material as claimed in claim 10 , exhibiting a translucent and frosted appearance when the particles of highly crosslinked acrylic copolymer have mean sizes ranging from 40 to 70 microns, and the refractive indices of the particles of the acrylic copolymer and of the block copolymer differ at 20° C. by more than 0.02 units.

14. The material as claimed in claim 10 , exhibiting a translucent and matt appearance when the elementary grains of the particles of highly crosslinked acrylic copolymer have sizes ranging from 1 to 40 μm.

15. An article comprising an acrylic material as claimed in claim said article being in the form of a film, part, profiled element, sheet or panel.

16. A process for the manufacture of an article as claimed in claim 15 , comprising an operation chosen from: injection molding, extrusion, coextrusion or extrusion/blow molding.

17. A multilayer structure comprising a first layer consisting of the material as claimed in claim 1 and a second layer comprising at least one substrate made of a thermoplastic polymer material.

18. The multilayer structure as claimed in claim 17 , in which the material according to the invention represents from 1% to 20% of the total thickness.

19. The multilayer structure as claimed in claim 17 , in which said substrate comprises at least one thermoplastic polymer selected from the group consisting of: PMMA, which is or is not high-impact, saturated polyesters, polyethylene terephthalate (PET), polyethylene terephthalate glycol-modified (PETg), polybutylene terephthalate (PBT), acrylonitrile/butadiene/styrene terpolymer (ABS), styrene/acrylonitrile copolymer (SAN), acrylic/styrene/acrylonitrile block copolymer (ASA), crystal or high-impact polystyrene (PS), polypropylene, polyethylene, polycarbonate, poly(2,6-dimethylphenylene oxide) (PPO), thermoplastic olefins (TPOs), polysulfones, polymers based on vinyl chloride, polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), expanded PVC, polyurethane (PU), thermoplastic polyurethane (TPU) and polyacetals.

Assignees

• Boutillier Jean-Marc
• Disson Jean-Pierre
• Arkema France

Inventors

• Boutillier Jean-Marc
• Disson Jean-Pierre

Classifications

• C08F220/1804

  C4-(meth)acrylate, e.g. butyl (meth)acrylate, isobutyl (meth)acrylate or tert-butyl (meth)acrylate · CPC title

• Y10T428/2495

  Thickness [relative or absolute] · CPC title

• C08L53/00 Primary

  Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers · CPC title

• Y10T428/31855

  Of addition polymer from unsaturated monomers · CPC title

• C08L2205/22

  Mixtures comprising a continuous polymer matrix in which are dispersed crosslinked particles of another polymer · CPC title