Block copolymer foam
The invention relates to a noncrosslinked block copolymer foam, comprising at least one rigid block and at least one flexible block, in which the copolymer includes at least one carboxylic acid chain end blocked with a polycarbodiimide. The invention also relates to a process for manufacturing this foam and to articles manufactured therefrom.
1. A noncrosslinked block copolymer foam, comprising at least one rigid block and at least one flexible block, characterized in that the copolymer includes at least one carboxylic acid chain end blocked with a polycarbodiimide.
2. The foam as claimed in claim 1 , wherein the weight-average molecular mass of the polycarbodiimide is greater than 10,000.
3. The foam as claimed in claim 1 , wherein the weight content of the polycarbodiimide represents from 0.5% to 10% by weight, relative to the total weight of the copolymer.
4. The foam as claimed in claim 1 , wherein said carboxylic acid forms a urea bond by reaction with a carbodiimide function of the polycarbodiimide.
5. The foam as claimed in claim 1 , wherein the copolymer is in noncrosslinked linear form, its dispersity Mw/Mn being less than 3.
6. The foam as claimed claim 1 , wherein said rigid block comprises at least one block chosen from: polyamide, polyurethane, polyester, and mixtures or copolymers thereof.
7. The foam as claimed claim 1 , wherein said flexible block comprises at least one block chosen from: polyether, polyester, polysiloxane, polyolefin, polycarbonate, and mixtures or copolymers thereof.
8. The foam as claimed in claim 1 , wherein said flexible block comprises at least one polyether (PE), selected from the group consisting of poly(tetramethyene glycol) (PTMG), poly(1,2-propylene glycol) (PPG), poly(1,3,propylene glycol) (P03G), poly(ethylene glycol) (PEG) and/or PEG and mixtures thereof.
9. The foam as claimed in claim 1 , wherein said flexible block comprises at least one polyester (PES), selected from the group consisting of polyester diols, poly(caprolactone) and polyesters based on fatty acid dimers.
10. The foam as claimed claim 1 , wherein said at least one copolymer comprises a copolymer containing polyamide blocks and polyether blocks.
11. The foam as claimed in claim 1 , wherein said rigid block comprises at least one polyamide PA, comprising at least one of the following polyamide units: 11, 12, 6, 610, 612, 1010, 1012, and mixtures or copolyamides thereof.
12. The foam as claimed in claim 1 , wherein the weight ratio of the rigid blocks to the flexible blocks is within the range from 0.3 to 10.
13. The foam as claimed in claim 1 , wherein said foam has a density of less than or equal to 800 kg/m 3 .
14. The foam as claimed in any claim 1 , wherein said foam further comprises one or more additives, selected from the group consisting of copolymers of ethylene and of vinyl acetate, copolymers of ethylene and of acrylate, and copolymers of ethylene and of alkyl (meth)acrylate.
15. An article comprising at least one element consisting of said foam as claimed in claim 1 .
16. The article of claim 15 consisting of said foam.
17. The article as claimed in claim 15 , wherein said article is selected from the group consisting of: a foam panel, a foam particle, a rod, a tube, an injection-molded and/or extruded part, a finished or semifinished object, a hollow object, and an object of any possible shape and any possible size made of foam.
18. The article as claimed in claim 15 , wherein said article is selected from the group consisting of: a shoe sole, sports shoes, an insole, a midsole, an outer sole, a ski boot inner shoe, a sock, a racket, an inflatable ball, a solid ball, a floater, gloves, personal protection equipment, a helmet, a rail sole, a motor vehicle part, a pushchair part, a tire, a wheel, a smooth-riding wheel, a handle, a seat element, a child car seat part, a construction part, an electrical and/or electronic equipment part, an electronic protection part, an audio equipment, acoustic insulation and/or heat insulation part, a part serving to dampen impacts and/or vibrations, a means of transport, a padding element, a toy, a medical object, a brace, an orthosis, a cervical collar, a dressing, an antimicrobial foam dressing, an art or handicraft object, a safety jacket, a backpack, a membrane, a carpet, a sports mat, a sports floor covering, a carpet underlay, and any article comprising a mixture of these articles.