Polyarylene foam materials

1. A foam material having one glass transition temperature (Tg), as measured by differential scanning calorimetry (DSC), and made by an extrusion process from an immiscible composition (C) having at least two glass transition temperatures (Tg), wherein said composition (C) comprises:

(i) from above 10 wt. % to below 75 wt. % of at least one polyarylene (P1) polymer, wherein more than 50% by moles (moles %) of the recurring units of said polyarylene (P1) polymer are recurring units (R1) consisting of an arylene group, wherein said arylene group is a hydrocarbon divalent group consisting of one core (C) composed of one benzene ring or of a plurality of benzene rings fused together by sharing two or more neighboring ring carbon atoms, said benzene ring being optionally substituted, wherein each of said arylene group is bound to two other arylene groups of neighboring recurring units (R1) through a first C—C bond (E1) and a second C—C bond (E2), wherein at least 20 moles % of recurring units (R1) are kink-forming arylene units (R1-b), arylene R1-b units, the remainder being rigid rod-forming arylene units (R1-a), arylene R1-a units, different from the arylene R1-b units, wherein in said arylene R1-a units the bond (E1) and the bond (E2) are co-linear and anti-parallel towards each other; and

(ii) from above 25 wt. % to below 90 wt. % of at least one polyphenylsulfone polymer, (PPSU) polymer, wherein more than 50% by moles of the recurring units of said (PPSU) polymer are recurring units (R PPSU ) of formula (A):

wherein the weight percentages are based on a total wt. % of the polyarylene (P1) polymer and the (PPSU) polymer, and the foam material has a density of 10 kg/m 3 to 50 kg/m 3 according to ASTM D792.

2. The foam material according to claim 1 , wherein the mole amount of the arylene R1-b units in the polyarylene (P1) polymer is in an amount from 45-55%, based on a total amount of moles of the recurring units (R1).

3. The foam material according to claim 1 , wherein the arylene R1-a units are p-phenylenes substituted by at least one monovalent substituting group chosen from arylketones and aryloxyarylketones, said arylketones and aryloxyarylketones being unsubstituted, or substituted by at least one monovalent substituting group.

4. The foam material according to claim 1 , wherein the arylene R1-b1 units are m-phenylenes optionally substituted by at least one monovalent substituting group.

5. The foam material according to claim 1 wherein the polyarylene (P1) polymer is a polyphenylene copolymer wherein more than 50% by moles of the recurring units are recurring units, (R Polyphenylene ), wherein at least 20 moles % of said recurring units (R Polyphenylene ) are arylene R 1-b units chosen from a m-phenylene, optionally substituted by at least one monovalent substituting group, or/and o-phenylene, optionally substituted by at least one monovalent substituting group, the remainder being p-phenylene, optionally substituted by at least one monovalent substituting group.

6. The foam material according to claim 1 , wherein the polyarylene (P1) polymer is present in an amount ranging from 25 to 50 wt. %, based on a total weight of the polyarylene (P1) polymer and the (PPSU) polymer.

7. The foam material according to claim 1 , wherein the glass transition temperature (Tg) of said foam material is of at least 150° C.

8. The foam material according to claim 1 , wherein the foam material has a substantially uniform cell size.

9. The foam material according to claim 1 , wherein a blowing agent is used in the extrusion process in an amount from 2 to 15% by weight based on a total weight of the composition (C).

10. The process according to claim 1 , wherein a nucleating agent is used in the extrusion process in an amount from 0.1 to 5.0% by weight based on a total weight of the composition (C).

11. The process according to claim 10 , wherein the nucleating agent is titanium dioxide or talc.

12. An article comprising at least one component comprising the foam material according to claim 1 .

13. The article of claim 12 wherein said article is a structural aircraft component or secondary aircraft component.

14. The article of claim 13 wherein said structural aircraft component is a sandwich panel comprising:

(i) a core comprising a foam material having one glass transition temperature (Tg), as measured by differential scanning calorimetry (DSC), and made by an extrusion process from an immiscible composition (C) having at least two glass transition temperatures (Tg), wherein said composition (C) comprises:

(i) from above 10 wt. % to below 75 wt. % of at least one polyarylene (P1) polymer, wherein more than 50% by moles (moles %) of the recurring units of said polyarylene (P1) polymer are recurring units (R1) consisting of an arylene group, wherein said arylene group is a hydrocarbon divalent group consisting of one core (C), composed of one benzene ring or of a plurality of benzene rings fused together by sharing two or more neighboring ring carbon atoms, said benzene ring being optionally substituted, wherein each of said arylene group is bound to two other arylene groups of neighboring recurring units (R1) through a first C—C bond (E1) and a second C—C bond (E2), wherein at least 20 moles % of recurring units (R1) are kink-forming arylene units (R1-b), arylene R1-b units, the remainder being rigid rod-forming arylene units (R1-a), arylene R1-a units, different from the arylene R1-b units, wherein in said arylene R1-a units the bond (E1) and the bond (E2) are co-linear and anti-parallel towards each other; and

(ii) from above 25 wt. % to below 90 wt. % of at least one polyphenylsulfone polymer, (PPSU) polymer, wherein more than 50% by moles of the recurring units of said (PPSU) polymer are recurring units (R PPSU ) of formula (A):

wherein the weight percentages are based on a total wt. % of the polyarylene (P1) polymer and the (PPSU) polymer; and

(ii) laminated skin layers comprised of a continuous fiber-reinforced thermoset or thermoplastic composite.

15. The foam material according to claim 9 , wherein the blowing agent is isopropanol or ethanol.

16. The foam material according to claim 1 , wherein the extrusion process is a continuous process.