Thermoplastic elastomer-silicone composition
A composition including: (A) a copolymer having rigid blocks and flexible blocks (TPE), (B) a non-crosslinked polysiloxane silicone, preferably a non-crosslinked polyorganosiloxane, (C) a compatibilizer, improving the compatibility between the TPE and the silicone, the compatibilizer (C) being chosen from a polyolefin or a mixture of polyolefins, and optionally (D) an additive.
1 . A composition comprising:
(A) a block copolymer having rigid blocks and flexible blocks (TPE), and
(B) a non-crosslinked polysiloxane silicone, wherein the non-crosslinked polyorganosiloxane has a poly(organo)siloxane backbone,
5% to 45% of (C) a compatibilizer, improving the compatibility between the TPE and the silicone, chosen from a polyolefin or a mixture of polyolefins, and wherein the polyolefin or the mixture of polyolefins of the compatibilizer (C) carries a functional group chosen from maleic anhydride, carboxylic acid, carboxylic anhydride, and epoxide,
wherein the non-crosslinked polysiloxane silicone is non-crosslinkable,
the composition comprising, by weight:
from 55% to 95% of copolymer (A),
from 5% to 45% of silicone (B),
from 5% to 45% of compatibilizer (C),
optionally, from 0% to 15% of at least one additive (D),
with regard to the total weight of the composition, this being 100%.
2 . The composition as claimed in claim 1 , wherein said rigid blocks comprise at least one block chosen from: polyamide, polyurethane, polyester, and their copolymers.
3 . The composition as claimed in claim 2 , wherein the polyamide blocks in the block copolymer (A) are PA 11 and/or PA 12 blocks.
4 . The composition as claimed in claim 1 , wherein said flexible blocks comprise at least one block chosen from: polyether, polyester, polysiloxane, polyolefin, polycarbonate, and their copolymers.
5 . The composition as claimed in claim 1 , wherein the block copolymer is chosen from copolymers having polyester blocks and polyether blocks, copolymers having polyurethane blocks and polyether blocks and copolymers having polyamide blocks and polyether blocks.
6 . The composition as claimed in claim 1 , wherein the flexible blocks in the copolymer (A) are polyether blocks chosen from PTMG, PPG, PO3G and/or PEG.
7 . The composition as claimed in claim 1 , wherein the number-average molar mass Mn of the flexible blocks, is greater than 800 g/mol.
8 . The composition as claimed in claim 1 , additionally comprising at least one additive (D) selected from the group consisting of: organic or inorganic fillers, reinforcing agents, plasticizers, stabilizers, antioxidants, UV stabilizers, flame retardants, carbon black, carbon nanotubes, pigments, dyes, mold-release agents, lubricants, foaming agents, impact-resistant agents, flame retardants, nucleating agents, surface-modifying agents and their mixtures.
9 . A process for the manufacture of the composition as claimed in claim 1 , comprising the step of mixing the block copolymer (A), the non-crosslinked silicone (B), and the compatibilizer (C).
10 . The process as claimed in claim 9 , wherein the mixing is carried out in a device for mixing in the molten state, at a temperature of the 150° C. to 250° C.
11 . An article comprising at least one part comprising the composition as claimed in claim 1 .
12 . The article as claimed in claim 11 , wherein said article is manufactured by a process involving at least one of the following stages: injection molding, overmolding, extrusion, or co-extrusion.
13 . The article as claimed in claim 11 , wherein said article is selected from the group consisting of a footwear sole, a sports footwear sole, an insole, midsole or outer sole, a ski boot liner, a sock, a racket, an inflatable ball, a solid ball, a floater, gloves, personal protection equipment, a helmet, a rail foot, a motor vehicle part, a pushchair part, a tire, a wheel, a smooth-riding wheel, a tire, 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 targeted at dampening impacts and/or vibrations, an article of transport, a padding element, a toy, a medical object, a splint, an orthosis, a cervical collar, a dressing, an antimicrobial foam dressing, an art or handicraft object, a life 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.
14 . The article as claimed in claim 11 , the article being selected from the group consisting of:
an article or article element of footwear;
an optical article or optical article element;
an automotive article or automotive article element;
an article or article element used in manufacturing industry;
a medical article or medical article element; and
an electronic article or electronic article element.
15 . The article as claimed in claim 11 , the article being an electrical or electronic article comprising a casing or protective casing, a portable telephone, or a tablet.
16 . The composition as claimed in claim 1 , the poly(organo)siloxane backbone having a polar functional group present at least at one of its ends.
17 . The composition as claimed in claim 16 , wherein the polar functional group is selected from the group consisting of a hydroxyl, an urea, an amine, an amide, a carboxylate, an ester, an acrylate, a thiol, a sulfonate, a sulfate and phosphate group.
18 . The composition as claimed in claim 1 , wherein the compatibilizer is a polymer exhibiting a flexural modulus of less than 100 MPa, measured according to the standard ISO 178, and a Tg of less than 0° C., measured according to the standard 11357-2 at the inflection point of the DSC thermogram.
19 . The composition as claimed in claim 1 , wherein the compatibilizer is chosen from the following copolymers, grafted with maleic anhydride or glycidyl methacrylate, in which the degree of grafting is from 0.01% to 5% by weight:
ethylene/octene copolymer, ethylene/butene copolymers, ethylene/propylene elastomers (EPR), ethylene-propylene-diene copolymers with an elastomeric nature (EPDM), ethylene/(meth)acrylate copolymers, and ethylene/butylene-styrene (SEBS) copolymer.
20 . The composition as claimed in claim 1 , wherein the compatibilizer is a ethylene/propylene copolymer, predominant in propylene, grafted by maleic anhydride and then condensed with monoaminated polyamide or a polyamide oligomer.
21 . The composition as claimed in claim 1 , wherein the compatibilizer is an ethylene copolymer, where ethylene represents at least 60% by weight and where the functional group represents from 0.1% to 10% by weight of the copolymer.
22 . The composition as claimed in claim 1 , wherein the composition has a Shore A hardness, 15 s, of less than 75.
23 . The composition as claimed in claim 1 , wherein the composition has a Shore A hardness, 15 s, of less than 70.
24 . The composition as claimed in claim 1 , wherein the ratio by weight of the rigid blocks, to the flexible blocks, in the copolymer (A) is less than or equal to 1.2.