High impact styrene/acrylonitrile polymer blend compositions

• US 6,008,282 A
• Filed: 11/26/1996
• Issued: 12/28/1999
• Est. Priority Date: 08/07/1990
• Status: Expired due to Fees

• Current Assignee: Exxon Chemical Patents Inc. (Exxon Mobil Corporation)
• Original Assignee: Exxon Chemical Patents Inc. (Exxon Mobil Corporation)
• Inventors: Yeh, Richard Cheng-Ming, Wang, Hsien-Chang
• Primary Examiner(s): Mulcahy, Peter D.
• Application Number:
  US08/756,470
• Time in Patent Office: 1,127 Days
• Field of Search: 524/399, 524/398, 524/434, 524/435
• US Class Current: 524/398
• CPC Class Codes: C08F 12/04 containing one ring
• CPC Class Codes: C08F 210/08 Butenes
• CPC Class Codes: C08F 210/10 Isobutene
• CPC Class Codes: C08F 210/14 Monomers containing five or more carbon atoms
• CPC Class Codes: C08F 212/04 containing one ring
• CPC Class Codes: C08F 212/12 Monomers containing a branched unsaturated aliphatic radical or a ring substituted by an alkyl radical
• CPC Class Codes: C08F 212/16 Halogens
• CPC Class Codes: C08F 2500/03 Narrow molecular weight distribution, i.e. Mw/Mn < 3
• CPC Class Codes: C08F 4/52 selected from boron, aluminium, gallium, indium, thallium or rare earths C08F4/14 takes precedence
• CPC Class Codes: C08F 8/00 Chemical modification by after-treatment graft polymers, block polymers, crosslinking with unsaturated monomers or with polymers C08F251/00 - C08F299/00; of conjugated diene rubbers C08C
• CPC Class Codes: C08F 8/20 Halogenation
• CPC Class Codes: C08G 81/021 Block or graft polymers containing only sequences of polymers of C08C or C08F
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C08L 101/00 Compositions of unspecified macromolecular compounds
• CPC Class Codes: C08L 23/02 not modified by chemical after-treatment
• CPC Class Codes: C08L 23/22 Copolymers of isobutene; Butyl rubber ; Homo- or copolymers of other iso-olefins
• CPC Class Codes: C08L 23/283 Halogenated homo- or copolymers of iso-olefins
• CPC Class Codes: C08L 25/12 with unsaturated nitriles
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 2666/06 : Homopolymers or copolymers of unsaturated hydrocarbons; Derivatives thereof
• 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 71/123 : not modified by chemical after-treatment

Abstract

Styrene/acrylonitrile (SAN) resin compositions are provided having both improved room temperature impact properties as well as good weatherability. The compositions comprise a mixture of SAN resin, an elastomeric halogenated copolymer comprising a C₂ to C₁₂ monoolefin, e.g. isobutylene, and a ring-substituted alklstyrene, e.g., para-methylstyrene, and a compatibilizing agent such as zinc stearate.

Claims

1. A thermoplastic polymer composition comprising a mixture of:

a) a halogenated elastomeric random copolymer having a saturated or low unsaturation backbone polymer segment and containing aromatic monomer units of the following structure distributed along the polymer backbone chain;

##STR3## wherein R and R'"'"' are independently selected from the group consisting of hydrogen and C₁ to C₄ alkyl, a X is bromine or chlorine, n is 1-3 and wherein the halogen content of the copolymer is 7 mole % or less and the halogen content of the backbone polymer is 2 mole % or less.

b) a copolymer of styrene and acrylonitrile; and

c) from about 0.5 to about 10 parts by weight per 100 parts by weight of the polymer content of the mixture of a compound selected from the group consisting of one or a mixture of;

aluminum compounds of a halide or a carboxylic acid selected from the group consisting of benzoic, naphthenic, alicyclic and C₁₀ to C₂₈ fatty acids,

iron compounds of a halide or a carboxylic acid selected from the group consisting of benzoic, naphthenic, alicyclic and C₁₀ to C₂₈ fatty acids,

tin compounds of a halide or a carboxylic acid selected from the group consisting of benzoic, naphthenic, alicyclic and C₁₀ to C₂₈ fatty acids, and

zinc compounds of a halide or a carboxylic acid selected from the group consisting of benzoic, naphthenic, alicyclic and C₁₀ to C₂₈ fatty acids, said elastomeric random copolymer present in said composition at a weight ratio of from about 5 to about 80 parts by weight per 100 parts by weight of said styrene/acrylonitrile copolymer.

2. The composition of claim 1 wherein said backbone is a polymer comprising one or a mixture of C₂ -C₁₂ polymerized mono-olefins and wherein said random copolymer contains from about 0.5 up to 20 mole % of said aromatic monomer units.

3. The composition of claim 1 wherein said compound comprises Zinc Stearate.

4. The composition of claim 1 wherein X is bromine.

5. The composition of claim 1 wherein said halogenated elastomeric random copolymer has a number average molecular weight of at least 10,000 comprising at least about 80 mole % of polymerized isomonoolefin containing from 4 to 7 carbon atoms and from about 0.05 up to about 20 mole % of aromatic monomer units comprising a mixture of the following structures randomly distributed therein:

##STR4## wherein R and R'"'"' are independently selected from the group consisting of hydrogen and C₁ to C₄ alkyl and X is bromine or chlorine.

6. The composition of claim 5 wherein said compatibilizing agent comprises zinc stearate.

7. The composition of claim 5 wherein X is bromine.

8. The composition of claim 5 wherein said halogenated copolymer is a copolymer of isobutylene and para-methylstyrene.

9. The composition of claim 8 wherein from about 5 to about 60% of the para-methylstyrene monomer units contain a mono-bromomethyl group.

10. The composition of claim 9 wherein said copolymer has a bromine content in the range of from about 0.1 to about 5 mole %.

11. The composition of claim 5 containing from about 1 to about 5 parts by weight of zinc stearate per 100 parts by weight of the polymer content of said composition.

12. The composition of claim 1 containing from about 10 to 50 parts by weight of said elastomeric random copolymer per 100 parts by weight of said styrene/acrylonitrile polymer.