Core and shell particle for modifying impact resistance of a mouldable poly (meth) acrylate material

• US 7,695,813 B2
• Filed: 10/18/2003
• Issued: 04/13/2010
• Est. Priority Date: 12/19/2002
• Status: Expired due to Fees

• Current Assignee: Evonik Rã¶Hm GmbH (Rag-Stiftung), Roehm GmbH & Co. KG
• Original Assignee: Roehm GmbH & Co. KG
• Inventors: Hoess, Werner, Schultes, Klaus, Albrecht, Klaus, Mueller, Reiner, Spiess, Andreas
• Primary Examiner(s): LE, HOA T
• Application Number:
  US10/539,509
• Publication Number:
  US 20060147714A1
• Time in Patent Office: 2,369 Days
• Field of Search: 428/403, 428/407, 523/201, 523/202, 523/220
• US Class Current: 428/407
• CPC Class Codes: C08F 265/04 on to polymers of esters
• CPC Class Codes: C08F 285/00 Macromolecular compounds obtained by polymerising monomers on to preformed graft polymers
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 33/12 Homopolymers or copolymers of methyl methacrylate
• CPC Class Codes: C08L 33/20 Homopolymers or copolymers of acrylonitrile C08L55/02 takes precedence
• CPC Class Codes: C08L 35/06 Copolymers with vinyl aromatic monomers
• CPC Class Codes: C08L 51/003 grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C08L51/04, C08L51/06 take precedence
• CPC Class Codes: C08L 51/04 grafted on to rubbers
• CPC Class Codes: C08L 55/005 Homopolymers or copolymers obtained by polymerisation of macromolecular compounds terminated by a carbon-to-carbon double bond
• CPC Class Codes: C08L 55/02 ABS [Acrylonitrile-Butadiene-Styrene] polymers
• CPC Class Codes: Y10T 428/2998 including synthetic resin or polymer

Abstract

The present invention relates to a core-shell particle which has a core, a first shell and, where appropriate, a second shell, where:

• i) the core encompasses, based on its total weight, at least 75.0% by weight of (meth)acrylate repeat units;
• ii) the first shell has a glass transition temperature below 30° C.;
• iii) the second shell present where appropriate encompassed, based on its total weight, at lest 75.0% by weight of (meth)acrylate repeat units;
• iv) the first shell encompasses, based on its total weight, the following constituents;
  • E) from 92.0 to 98.0% by weight of (meth)acrylate repeat units and
  • F) from 2.0 to 8.0% by weight of styrenic repeat units of the general formula (I)

• •  where the radicals R¹ to R⁶ are defined according to the Description and the percentages by weight of E) and F) give a total of 100.0% by weight,
• v) the radius of the core-shell particle inclusive of any second shell present, measured by the Coulter method, is in the range from above 160.0 to 240.0 nm;
  a process for preparing core-shell particles, to a moulding composition comprising core-shell particles, and to the use thereof.

Claims

1. A core-shell particle which has a core, a first shell and, optionally, a second shell, where:

i) the core comprises, based on its total weight, at least 75.0% by weight of (meth)acrylate repeat units;

ii) the first shell has a glass transition temperature below 30°

C.;

iii) the second shell optionally comprises, based on its total weight, at least 75.0% by weight of (meth)acrylate repeat units;

wherein

iv) the first shell comprises, based on its total weight, the following constituents;

E) from 92.0 to 98.0% by weight of (meth)acrylate repeat units and

F) from 2.0 to 8.0% by weight of styrenic repeat units of formula (I)

2. The core-shell particle according to claim 1, wherein, based in each case on its total weight,

i) the proportion of the core is from 5.0 to 50.0% by weight,

ii) the proportion of the first shell is from 20.0 to 75.0% by weight and

iii) the proportion of the second shell is from 0.0 to 50.0% by weight,

where the percentages by weight give a total of 100.0% by weight.

3. The core-shell particle according to claim 1, wherein the core comprises, based in each case on its total weight,

A) from 50.0 to 99.9% by weight of alkyl methacrylate repeat units having from 1 to 20 carbon atoms in the alkyl radical,

B) from 0.0 to 40.0% by weight of alkyl acrylate repeat units having from 1 to 20 carbon atoms in the alkyl radical,

C) from 0.1 to 2.0% by weight, of crosslinking repeat units and

D) from 0.0 to 8.0% by weight of styrene repeat units of the general formula (I),

where the percentages by weight give a total of 100% by weight.

4. The core-shell particle according to claim 3, wherein the core comprises, based in each case on its total weight, from 80.0 to 99.9% by weight of methyl methacrylate repeat units and from 1.0 to 20.0% by weight of alkyl acrylate repeat units having from 1 to 4 carbon atoms in the alkyl radical, where the percentages by weight give a total of 100.0% by weight.

5. The core-shell particle according to claim 1, wherein the first shell comprises, based in each case on its total weight,

E-1) from 90.0 to 97.9% by weight of alkyl acrylate repeat units having from 3 to 8 carbon atoms in the alkyl radical and/or alkyl methacrylate repeat units having from 7 to 14 carbon atoms in the alkyl radical,

E-2) from 0.1 to 2.0% by weight of crosslinking repeat units and

F) from 2.0 to 8.0% by weight of styrenic repeat units of formula (I),

where the percentages by weight give a total of 100.0% by weight.

6. The core-shell particle according to claim 5, wherein the alkyl acrylate repeat units having from 3 to 8 carbon atoms in the alkyl radical and/or alkyl methacrylate repeat units having from 7 to 14 carbon atoms in the alkyl radical are butyl acrylate repeat units and/or dodecyl methacrylate repeat units.

7. The core-shell particle according to claim 1, wherein the core-shell particle has a second shell which, based in each case on its total weight, comprises

G) from 50.0 to 100.0% by weight of alkyl methacrylate repeat units having from 1 to 20 carbon atoms in the alkyl radical,

H) from 0.0 to 40.0% by weight of alkyl acrylate repeat units having from 1 to 20 carbon atoms in the alkyl radical and

I) from 0.0 to 8.0% by weight of styrenic repeat units of formula (I), where the percentages by weight give a total of 100.0% by weight.

8. The core-shell particle according to claim 1, wherein the core has a glass transition temperature of at least 30°

C.

9. The core-shell particle according to claim 1, wherein the core-shell particle has a second shell, which has a glass transition temperature of at least 30°

C.

10. A process for preparing a core-shell particle according to claim 1, wherein comprises:

polymerizing the monomer of each stage of said core, first shell and second shell under multistage emulsion polymerization conditions.