EXPANDED ARTICLES WITH EXCELLENT RESISTANCE TO SOLAR RADIATION AND OPTIMUM THERMOINSULATING AND MECHANICAL PROPERTIES

• US 20120091388A1
• Filed: 04/23/2010
• Published: 04/19/2012
• Est. Priority Date: 05/05/2009
• Status: Abandoned Application

• Current Assignee: Polimeri Europa SPA (Eni Petroleum Company Incorporated)
• Original Assignee: Polimeri Europa SPA (Eni Petroleum Company Incorporated)
• Inventors: Felisari, Riccardo, Ponticiello, Antonio, Ghidoni, Dario
• Application Number:
  US13/318,702
• Publication Number:
  US 20120091388A1
• Time in Patent Office: Days
• US Class Current: 252/62
• CPC Class Codes: C08J 2325/04 Homopolymers or copolymers of styrene
• CPC Class Codes: C08J 2471/00 Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain of polyacetals C08J2459/00; of epoxy resins C08J2463/00; of polythioether-ethers C08J2481/02; of polyethersulfones C08J2481/06; Derivatives of such polymers
• CPC Class Codes: C08J 9/0061 characterized by the use of several polymeric components
• CPC Class Codes: C08J 9/0066 Use of inorganic compounding ingredients
• CPC Class Codes: C08J 9/232 by sintering expandable particles

Abstract

A thermoinsulating expanded article with improved resistance to solar irradiation, which includes an expanded polymeric matrix, obtained by the expansion and sintering of beads or granules containing a vinyl aromatic (co)polymer, where the interior of the beads or granules contains a homogeneously dispersed filler containing at least one athermanous material selected from coke, graphite and carbon black and optionally contains an active inorganic additive within the wave-lengths ranging from 100 to 20,000 cm⁻¹. The polymeric matrix contains a copolymer of styrene and at least one vinyl aromatic comonomer substituted in the ring or on the vinyl group, a mixture of polystyrene and up to 10% by weight, with respect to the mixture, of a thermoplastic polymer compatible with polystyrene and having a Tg>100° C., or both.

Claims

1. A theromoinsulating expanded article, comprising an expanded polymeric matrix, obtained by an expansion and a sintering of beads or granules comprising a vinyl aromatic (co)polymer, wherein an interior of the beads or granules comprises a is homogeneously dispersed filler

wherein the filler, comprises:

a. 0.1-10% by weight of at least one selected from the group consisting of coke having an average diameter (MT50) in a range from 2 to 20 μ

m, synthetic, natural, or expanded graphite having an average diameter (MT50) in a range from 1 to 20 μ

m, and carbon black having a surface area in a range from 10 to 60 m²/g;

b. 0-5% by weight of a self-extinguishing brominated additive, optionally thermally stabilized;

c. 0-2% by weight of a synergist for the self-extinguishing additive (b);

d. 0-10% by weight of at least one inorganic additive active at at least one wave-length in a range from 100 to 20,000 cm<sup>−

1</sup>;

e. 1-10% by weight of an expanding agent,

wherein the percentages are based on an overall weight of the bead or granule and

wherein a complement to 100% is a polymeric matrix (f) comprising at least one selected from the group consisting of a copolymer (f1) of styrene and at least one vinyl aromatic comonomer substituted in a ring or on a vinyl group and a mixture (f2) of polystyrene and a thermoplastic polymer compatible with polystyrene and having a Tg>

100°

C.

2. A flat sheet comprising the expanded article of claim 1, the sheet having a density in a range from 8 to 50 g/l and a thickness of 1 to 50 cm.

4. The article of claim 1, wherein the copolymer (f1) comprises the vinyl aromatic comonomer in a range from 0.001 to 15% by weight, with respect to the copolymer (f1).

5. The article of claim 4, wherein the comonomer is at least one selected from the group consisting of α

-methylstyrene and para-methylstyrene.

6. The article of claim 1, wherein the polymeric mixture (f2) comprises up to 10% by weight of the thermoplastic polymer, with respect to the polymeric mixture (f2).

7. The article of claim 6, wherein the compatible thermoplastic polymer is polyphenylene-oxide.

8. The article of claim 1, wherein the at least one inorganic additive (d) comprises an inorganic material having at least one absorption band between 100 and 20,000 cm⁻

1 and is at least one selected from the group consisting of a titanate, a titanium oxide, a silicon oxide, an aluminum oxide, an aluminum hydroxide, a barium sulfate, a silicate, a carbonate, a calcium sulfate, a calcium oxide, a zinc oxide, and a bentonite.

3. An expanded extruded sheet, comprising:

A. a filler comprising

a. 0.1-10% by weight of at least one selected from the group consisting of coke having an average diameter (MT50) in a range from 2 to 20 μ

m, synthetic, natural, or expanded graphite having an average diameter (MT50) in a range from 1 to 20 μ

m, and carbon black having a surface area in a range from 10 to 60 m²/g,

b. 0-5% by weight of a self-extinguishing brominated additive, optionally thermally stabilized,

c. 0-2% by weight of a synergist for the self-extinguishing additive (b), and

d. 0-10% by weight of at least one inorganic additive active at at least one wave-length in a range from 100 to 20,000 cm<sup>−

1</sup>; and

B. a continuous cellular matrix comprising at least one selected from the group consisting of

(f1) a vinyl aromatic copolymer comprising styrene and at least one vinyl aromatic comonomer substituted in a ring or on a vinyl and

(f2) a mixture of polystyrene and a thermoplastic polymer compatible with polystyrene and having a Tg>

100°

C.,

wherein the expanded sheet has a density in a range from 10 to 200 g/l, and an average cell dimension of the cellular matrix ranging from 0.05 to 1.00 mm.

9. A bead or granule, comprising:

A. a vinyl aromatic polymeric matrix comprising at least one selected from the group consisting of

a copolymer (f1) comprising styrene and at least one vinyl aromatic comonomer substituted in a ring or on a vinyl group and

a mixture (f2) comprising polystyrene and a thermoplastic polymer compatible with polystyrene and having a Tg>

100°

C.; and

B. a filler comprising

a. 0.1-10% by weight of at least one selected from the group consisting of coke having an average diameter (MT50) in a range from 2 to 20 μ

m, synthetic, natural or expanded graphite having an average diameter ranging from 1 to 20 μ

m, and carbon black having surface area in a range from 10 to 60 m²/g,

b. 0-5% by weight of a self-extinguishing brominated additive, optionally thermally stabilized,

c. 0-2% by weight of a synergist for the self-extinguishing additive (b),

d. 0-10% by weight of at least one inorganic additive active at at least one wave-length in a range from 100 to 20,000 cm<sup>−

1</sup>, and

e. 1-10% by weight of an expanding agent,

wherein the percentages are based on a total of the A and B.

10. The bead or granule of claim 9, comprising the vinyl aromatic comonomer in a range from 0.001 to 15% by weight with respect to the copolymer.

11. The bead or granule of claim 10, wherein the comonomer is at least one selected from the group consisting of α

-methylstyrene and para-methylstyrene.

12. The bead or granule of claim 9, comprising the thermoplastic polymer in a range up to 10% by weight, with respect to the polymeric mixture (f2).

13. The bead or granule of claim 12, wherein the compatible thermoplastic polymer is polyphenylene-oxide.

14. A process for the preparation of the bead or granule of claim 9, the process comprising:

dissoluting and dispersing the filler comprising (a)-(d) in a monomeric phase, and then

polymerizing in an aqueous suspension, and adding the expanding agent (e).

15. A process for the preparation of the granule of claim 9, which comprising:

I. mixing the vinyl aromatic (co)polymer having an average molecular weight Mw in a range from 50,000 to 250,000 with the filler (a)-(d) to obtain a polymeric mixture and a molten mixture when the vinyl aromatic (co)polymer is in granules and in a molten state, respectively, and optionally mixing at least one selected from the group consisting of the compatible thermoplastic polymer and a further additive;

II. optionally, heating the polymeric mixture, if not already in the molten state, to a temperature higher than the melting point of the vinyl aromatic (co)polymer, to obtain a molten mixture.

III. adding the expanding agent (e) and optionally a part of or all of the further additive, to the molten mixture to obtain a polymeric composition;

IV. mixing the polymeric composition with a static or a dynamic mixing element; and

V. granulating the polymeric composition in a device comprising a die, a cutting chamber, and a cutting system.