阅读说明：本技术 热塑性弹性体组合物 (Thermoplastic elastomer composition ) 是由 Y.卢 X.张 X.郑 Q.李 于 2020-04-22 设计创作，主要内容包括：公开了热塑性弹性体组合物和制造热塑性弹性体的方法。热塑性弹性体可包括聚合物共混物。聚合物混合物可包含非交联弹性体、油、聚乙烯和抗氧化剂。油可为约15重量％至约50重量％。聚乙烯可以是约3wt％至约30重量％。抗氧化剂可为约0至约0.5重量％。(Thermoplastic elastomer compositions and methods of making thermoplastic elastomers are disclosed. The thermoplastic elastomer may comprise a polymer blend. The polymer mixture may comprise a non-crosslinked elastomer, an oil, a polyethylene, and an antioxidant. The oil may be about 15 wt% to about 50 wt%. The polyethylene can be about 3 wt% to about 30 wt%. The antioxidant can be about 0 to about 0.5 wt%.)

1. A thermoplastic elastomer composition comprising, in a blend,

a polymer blend comprising a non-crosslinked elastomer;

from about 15 wt% to about 50 wt% oil;

from about 3.0 wt% to about 30 wt% polyethylene; and

about 0 to about 0.5 wt.% antioxidant.

2. The thermoplastic elastomer composition of claim 1, wherein the oil comprises mineral oil.

3. The thermoplastic elastomer composition of claim 1, wherein the non-crosslinked elastomer comprises a styrenic block copolymer.

4. The thermoplastic elastomer composition of claim 3, wherein the styrene block copolymer is selected from the group consisting of styrene-butadiene-styrene polymer (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene-styrene (SIS), styrene-isoprene-butadiene-styrene (SIBS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-propylene (SEP) block copolymer, styrene-ethylene-propylene-styrene (SEEPS), hydrogenated polybutadiene, hydrogenated polyisoprene, hydrogenated styrene-isoprene random copolymer, poly (styrene- [ (butadiene)_1-x- (ethylene-co-butene)_x]Styrene), where x is the hydrogenated portion of the molecule, and hydrogenated styrene-butene random copolymers.

5. The thermoplastic elastomer composition of claim 4, wherein the styrenic block copolymer comprises a styrene-ethylene-butylene-styrene polymer.

6. The thermoplastic elastomer composition of claim 5, wherein the styrenic block copolymer comprises from about 20 wt% to about 50 wt% of a styrene-ethylene-butylene-styrene polymer.

7. The thermoplastic elastomer composition of claim 5, wherein the styrene-ethylene-butylene-styrene polymer has a total molecular weight of from about 100,000 to about 440,000 g/mol.

8. The thermoplastic elastomer composition of claim 2, wherein the mineral oil comprises a paraffin oil.

9. The thermoplastic elastomer composition of claim 7, wherein the styrene-ethylene-butylene-styrene polymer has an overall molecular weight of from about 200,000g/mol to about 440,000 g/mol.

10. The thermoplastic elastomer composition of claim 1, wherein the polyethylene comprises a Linear Low Density Polyethylene (LLDPE).

11. The thermoplastic elastomer composition of claim 1, wherein the styrene-ethylene-butylene-styrene polymer has an overall molecular weight of from about 240,000g/mol to about 440,000 g/mol.

12. The thermoplastic elastomer composition of claim 10, wherein the linear low density polyethylene has a melt flow index of from about 0.5g/10min to about 10.0g/10min, measured at 230 ℃, using a 2.16 kilogram (kg) weight.

13. The thermoplastic elastomer composition of claim 1, wherein the thermoplastic elastomer has a shore a hardness of about 20 to 95A.

14. The thermoplastic elastomer composition of claim 1, wherein the thermoplastic elastomer has a weight percent of non-crosslinked elastomer to oil (when present) of about 0.4 to about 2.5.

15. The thermoplastic elastomer composition of claim 14, wherein the weight percent is from about 0.7 to about 1.5.

16. The thermoplastic elastomer composition of claim 1, wherein the thermoplastic elastomer has a melt viscosity of about 200 to about 2000pa.s, measured at a shear rate of 671/s, measured at 200 ℃.

17. The thermoplastic elastomer composition of claim 1, wherein the thermoplastic elastomer has a melt viscosity of about 500 to about 1300pa.s, measured at a shear rate of 671/s at 200 ℃.

18. The thermoplastic elastomer composition of claim 1, wherein the thermoplastic elastomer has a melt viscosity of about 200 to about 500pa.s, measured at a shear rate of 671/s, measured at 200 ℃.

19. The thermoplastic elastomer composition of claim 1, wherein the thermoplastic elastomer has a melt viscosity of about 700 to about 1100pa.s, measured at a shear rate of 671/s at 200 ℃.

20. The thermoplastic elastomer composition of claim 1, wherein the non-crosslinked elastomer has a total molecular weight of from about 100,000 to about 440,000 g/mol.

21. The thermoplastic elastomer composition of claim 1, wherein the non-crosslinked elastomer has a total molecular weight of from about 200,000 to about 400,000 g/mol.

22. The thermoplastic elastomer composition of claim 1, wherein the non-crosslinked elastomer has a total molecular weight of about 240,000 to about 400,000 g/mol.

23. A thermoplastic elastomer composition comprising, in a blend,

a polymer blend comprising a styrenic block copolymer;

from about 15% to about 50% by weight of an oil;

from about 5% to about 30% by weight of polyethylene; and

about 0 to about 0.5 wt.% of an antioxidant, wherein the thermoplastic elastomer has a melt viscosity of about 200 to about 2000 at a shear rate of 671/s measured at about 200 ℃.

24. The thermoplastic elastomer composition of claim 23, wherein the oil comprises a mineral oil.

25. The thermoplastic elastomer composition of claim 23, wherein the styrene block copolymer is selected from the group consisting of styrene-butadiene-styrene (SBS), styrene-ethylene butylene-styrene (SEBS), styrene-isoprene-styrene (SIS), styrene-isoprene-butadiene-styrene (SIBS), styrene-ethylene propylene-styrene (SEPS), and styrene-ethylene propylene (SEP) block copolymersStyrene-ethyleneethylenepropylene-styrene (SEEPS), hydrogenated polybutadiene, hydrogenated polyisoprene, hydrogenated styrene-isoprene random copolymer, poly (styrene- [ (butadiene)_1-x- (ethylene-co-butene)_x]Styrene), where x is the hydrogenated portion of the molecule, and hydrogenated styrene-butene random copolymers.

26. The thermoplastic elastomer composition of claim 23, wherein the styrenic block copolymer comprises a styrene-ethylene-butylene-styrene polymer.

27. The thermoplastic elastomer composition of claim 23, wherein the styrenic block copolymer comprises from about 20 wt.% to about 50 wt.% styrene-ethylene-butylene-styrene polymer.

28. The thermoplastic elastomer composition of claim 27, wherein the total molecular weight of the styrene-ethylene-butylene-styrene polymer is from 100,000 to 440,000 g/mol.

29. The thermoplastic elastomer composition of claim 23, wherein the mineral oil comprises a paraffin oil.

30. The thermoplastic elastomer composition of claim 28, wherein the total molecular weight of the styrene-ethylene-butylene-styrene polymer is from 2000,000g/mol to 440,000 g/mol.

31. The thermoplastic elastomer composition of claim 23, wherein the polyethylene comprises a Linear Low Density Polyethylene (LLDPE).

32. The thermoplastic elastomer composition of claim 28, wherein the styrene-ethylene-butylene-styrene polymer has an overall molecular weight of 240,000 to 440,000 g/mol.

33. The thermoplastic elastomer composition of claim 23, wherein the thermoplastic elastomer has a shore a hardness of about 20 to about 95A.

34. The thermoplastic elastomer composition of claim 23, wherein the weight percent of styrene block copolymer to oil (if present) of the thermoplastic elastomer has from about 0.4 to about 2.5.

35. The thermoplastic elastomer composition of claim 34, wherein the weight percent is from about 0.7 to about 1.5.

36. The thermoplastic elastomer composition of claim 23, wherein the thermoplastic elastomer has a melt viscosity of about 200 to about 2000pa.s, measured at a shear rate of 671/s, measured at 200 ℃.

37. The thermoplastic elastomer composition of claim 36, wherein the thermoplastic elastomer has a melt viscosity of about 500 to about 1300pa.s, measured at a shear rate of 671/s at 200 ℃.

38. The thermoplastic elastomer composition of claim 36, wherein the thermoplastic elastomer has a melt viscosity of about 700 to about 1100pa.s, measured at a shear rate of 671/s at 200 ℃.

39. A thermoplastic elastomer composition comprising, in a blend,

polymer blends comprising styrene block copolymers selected from the group consisting of styrene-butadiene-styrene polymers (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-isoprene-styrene (SIS), styrene-isoprene-butadiene-styrene (SIBS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-propylene (SEP) block copolymers, styrene-ethylene-propylene-styrene (SEEPS), hydrogenated polybutadiene, hydrogenated polyisoprene, hydrogenated styrene-isoprene random copolymers, poly (styrene- [ (butadiene)_1-x- (ethylene-co-butene)_x-styrene) in which x is the hydrogenation fraction of the molecule, hydrogenStyrene-butylene random copolymers;

from about 15 wt% to about 50 wt% oil;

from about 3 wt% to about 30 wt% polyethylene; and

about 0 to about 0.5 wt.% antioxidant, wherein the thermoplastic elastomer has a weight percent of styrene block copolymer to oil (when present) of about 0.4 to about 2.5.

40. The thermoplastic elastomer composition of claim 39, wherein the oil comprises mineral oil.

41. The thermoplastic elastomer composition of claim 39, wherein the styrenic block copolymer comprises a styrene-ethylene-butylene-styrene polymer.

42. The thermoplastic elastomer composition of claim 39, wherein the styrenic block copolymer comprises from about 25 wt% to about 50 wt% of a styrene-ethylene-butylene-styrene polymer.

43. The thermoplastic elastomer composition of claim 39, wherein the mineral oil comprises a paraffin oil.

44. The thermoplastic elastomer composition of claim 39, wherein the total molecular weight of the styrene-ethylene-butylene-styrene polymer is from 200,000 to 440,000 g/mol.

45. The thermoplastic elastomer composition of claim 39, wherein the polyethylene comprises a Linear Low Density Polyethylene (LLDPE).

46. The thermoplastic elastomer composition of claim 39, wherein the styrene-ethylene-butylene-styrene polymer has an overall molecular weight of 240,000g/mol to 440,000 g/mol.

47. The thermoplastic elastomer composition of claim 39, wherein the styrene-ethylene-butylene-styrene polymer has an overall molecular weight of 100,000g/mol to 440,000 g/mol.

48. The thermoplastic elastomer composition of claim 39, wherein the thermoplastic elastomer has a Shore A hardness of about 20 to about 95A.

49. The thermoplastic elastomer composition of claim 39, wherein the weight percent of styrene block copolymer to oil (when present) of the thermoplastic elastomer is from about 0.4 to about 2.5.

50. The thermoplastic elastomer composition of claim 39, wherein the weight percent is from about 0.7 to about 1.5.

51. The thermoplastic elastomer composition of claim 39, wherein the thermoplastic elastomer has a melt viscosity of about 200 to about 2000Pa.s at a shear rate of 671/s, measured at 200 ℃.

52. The thermoplastic elastomer composition of claim 39, wherein the thermoplastic elastomer has a melt flow viscosity of about 500 to about 1300Pa.s at a shear rate of 671/s, measured at 200 ℃.

53. The thermoplastic elastomer composition of claim 39, wherein the thermoplastic elastomer has a melt viscosity of about 700 to about 1100Pa.s at a shear rate of 671/s, measured at 200 ℃.

54. The thermoplastic elastomer composition of claim 39, wherein the thermoplastic elastomer has a viscosity of about 800 to about 1000Pa.s at a shear rate of 671/s, measured at 200 ℃.

55. The thermoplastic elastomer composition of claim 39, wherein the styrenic block copolymer has an overall molecular weight of 100,000 to 440,000 g/mol.

56. The thermoplastic elastomer composition of claim 39, wherein the styrenic block copolymer has an overall molecular weight of 200,000 to 400,000 g/mol.

57. The thermoplastic elastomer composition of claim 39, wherein the styrene block copolymer has an overall molecular weight of 240,000 to 400,000 g/mol.

Technical Field

The present disclosure relates generally to thermoplastic elastomer compositions, and more particularly to thermoplastic elastomer compositions having low compression set and good melt strength.

Background

An increasingly significant problem in the wine industry today is that large quantities of traditionally naturally sealed wine are damaged by contaminated, unsuitable or spoiled cork.

It is estimated that about 5-10% of the wine is affected to a certain extent, and in some cases the wine will have to be discarded, since the cork is deteriorated, which means that the porous and imperfect material (wood) bark) is contaminated or infected, which changes its chemical properties during contact with the wine, thereby impairing its quality. "Cork" can be affected and, depending on the severity of the contamination, it may exhibit symptoms ranging from a musty smell to a change in the taste of the wine, flattening and being unorganized.

Therefore, there is a need to develop synthetic wine cork stoppers of resilient material with low compression set and good melt strength.

Summary of the invention

According to the first aspect, the thermoplastic elastomer may comprise a polymer blend. The polymer blend may comprise a non-crosslinked elastomer, an oil, a polyethylene, and an antioxidant. The oil may be about 15 wt% to about 50 wt%. The polyethylene may be about 3.0 wt% to about 30 wt%. The antioxidant can be about 0 to about 0.5 wt%.

In certain aspects, the oil comprises a mineral oil.

In certain aspects, the non-crosslinked elastomer may comprise a styrenic block copolymer.

In certain aspects, the styrene block copolymer may be selected from the group consisting of styrene-ethylene-butadiene-styrene polymers, styrene-ethylene-butylene-styrene, styrene-ethylene-propylene-styrene (SEPS), hydrogenated polybutadiene, hydrogenated polyisoprene, hydrogenated styrene-isoprene random copolymers, styrene-ethylene-propylene (SEP) block copolymers, styrene-ethylene-propylene-styrene (SEEPS), and hydrogenated styrene-butadiene random copolymers.

In certain aspects, the styrene block copolymer may comprise a styrene-ethylene-butylene-styrene polymer.

In certain aspects, the styrenic block copolymer can comprise about 20 wt% to about 50 wt% styrene-ethylene-butylene-styrene polymer.

In certain aspects, the total molecular weight of the styrene-ethylene-butylene-styrene polymer is from 100,000 to 440,000 g/mol.

In certain aspects, the mineral oil can comprise a paraffinic oil.

In certain aspects, the total molecular weight of the styrene-ethylene-butylene-styrene polymer is from 200,000g/mol to 440,000 g/mol. In certain aspects, the polyethylene may comprise Linear Low Density Polyethylene (LLDPE).

In certain aspects, the total molecular weight of the styrene-ethylene-butylene-styrene polymer is from 240,000g/mol to 440,000 g/mol. In certain aspects, the linear low density polyethylene has a melt flow index of about 0.5 to about 10.0 grams/10 minutes, measured at 230 ℃, using a 2.16 kilogram (kg) weight.

In certain aspects, the thermoplastic elastomer has a shore a hardness of about 30 to 95A.

In certain aspects, the thermoplastic elastomer has a weight percent of non-crosslinked elastomer to oil (when present) of about 0.4 to about 2.5.

In certain aspects, the weight percentage is about 0.7 to about 1.5.

In certain aspects, the thermoplastic elastomer has a melt viscosity of about 200 to about 2000pa.s at a shear rate of 671/s, measured at 200 ℃.

In certain aspects, the thermoplastic elastomer has a melt viscosity of about 500 to about 1300pa.s at a shear rate of 671/s, measured at 200 ℃.

In certain aspects, the thermoplastic elastomer has a melt viscosity of about 200 to about 500pa.s at a shear rate of 671/s, measured at 200 ℃.

In certain aspects, the thermoplastic elastomer has a melt viscosity of about 700 to about 1100pa.s at a shear rate of 671/s, measured at 200 ℃.

In certain aspects, the non-crosslinked elastomer has an overall molecular weight of about 100,000 to about 440,000 g/mol.

In certain aspects, the non-crosslinked elastomer has a total molecular weight of about 200,000 to about 400,000 g/mol.

According to a second aspect, the thermoplastic elastomer may comprise a polymer blend. The polymer blend may comprise a styrenic block copolymer, an oil, a polyethylene, an antioxidant. The oil may be about 15 wt% to about 50 wt%, the polyethylene may be about 3 wt% to about 30 wt%, and the antioxidant may be about 0 to about 0.5 wt% antioxidant. The thermoplastic elastomer may have a melt viscosity of about 200 to about 2000 at a shear rate of 671/s measured at about 200 ℃. According to a second aspect, the thermoplastic elastomer may comprise a polymer blend. The polymer blend may comprise a styrenic block copolymer, an oil, a polyethylene, and an antioxidant. The oil may be about 15 wt% to about 50 wt%. The polyethylene can be about 3 wt% to about 30 wt%. The antioxidant can be about 0 to about 0.5 wt%. The weight percent of styrene block copolymer to oil in the thermoplastic elastomer, if present, can be from about 0.4 to about 2.5. The styrene block copolymer may be selected from the group consisting of styrene-ethylene-butylene-styrene polymers, styrene-ethylene-butylene-styrene, styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-propylene (SEP) block copolymers, styrene-ethylene-propylene-styrene (SEEPS), and hydrogenated styrene-butadiene random copolymers.

Detailed Description

In the following description, well-known functions or constructions are not described in detail since they would obscure the disclosure in unnecessary detail. For the purposes of this disclosure, the following terms and definitions shall apply.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of claimed subject matter. Thus, the appearances of the phrase "in one embodiment" or "an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in one or more embodiments.

Furthermore, variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Further, two or more steps may be performed simultaneously or partially simultaneously. Further, the steps of the method may be performed in an order different than that disclosed. Such variations will depend on the process hardware system selected and the designer's choice. All such variations are within the scope of the present disclosure. Furthermore, even though the disclosure has been described with reference to specific exemplifying embodiments thereof, many different alterations, modifications and the like will become apparent for those skilled in the art.

Embodiments include thermoplastic elastomeric material compositions, methods of making the compositions, and articles made from the compositions. In one embodiment, a thermoplastic elastomer composition is provided that includes a polymer blend of about 15% to about 50% styrene-ethylene-butadiene-styrene (SEBS) polymer; about 15% to about 50% oil; about 3.0% to about 30% polyethylene; and from about 0 to about 0.5% of an antioxidant.

As used herein, the term "polymer" refers to the product of a polymerization reaction, including homopolymers, copolymers, terpolymers, and the like. As used herein, unless otherwise specified, the term "copolymer" refers to a polymer formed by polymerizing at least two different monomers. For example, the term "copolymer" includes the copolymerization product of ethylene and an α -olefin, such as 1-hexene. However, the term "copolymer" also includes, for example, the copolymerization of a mixture of ethylene, propylene, 1-hexene and 1-octene.

As used herein, when a polymer is referred to as "comprising a monomer," the monomer is present in the polymer in the polymerized form of the monomer or in the form of a derivative of the monomer.

As used herein, "molecular weight" refers to weight average molecular weight ("Mw"). Mw is determined using gel permeation chromatography. Molecular weight distribution ("MWD") may be defined or measured as Mw divided by the number average molecular weight ("Mn"). (for more information, see Cozewith et al, U.S. Pat. No. 4,540,753 and references cited therein, and Ver Strate et al, 21Macromolecules, pp.3360-3371 (1998)). The "Mz" value is a high average molecular weight value and is calculated as discussed in A.R. Cooper in the concise encyclopedia of Polymer science and engineering, pp 638-.

The term "active agent" refers to a substance that is capable of providing a particular activity or function to a user. Suitable active agents may be in a variety of geometric forms including discrete particles, fibers, flakes, rods, spheres, needles, fiber coated particles, and the like.

The term "compression" refers to the process or result of applying pressure on an object to increase the density of the object. The terms "elastomer," "elastic if," and other derivatives of "elastomer" are used interchangeably to refer to a material having elastic or rubbery characteristics. Elastomeric materials, such as thermoplastic elastomers and thermoplastic vulcanizates, are generally capable of recovering their shape after deformation after removal of the deforming force. Specifically, as used herein, elastic refers to any material's property that allows the material to stretch to a stretched length that is at least about 25% greater than its relaxed length upon application of a stretching force, and which will allow the material to recover at least 40% of its elongation upon release of the tensile elongation force. A hypothetical example of this definition of an elastic material that would satisfy in the XY plane dimensions is a one (1) inch sample of material that can be stretched to at least 1.25 inches and upon stretching to 1.25 inches and being released, will recover to a length of no more than 1.15 inches. Many elastic materials can be stretched beyond 25% of their relaxed length and can return to substantially their original relaxed length upon release of a stretching, elongating force. In addition to materials that are elastic in the noted X-Y planar dimension of the structure, including webs or sheets, the material may be elastic in the Z-plane dimension. In particular, when the structure is subjected to a compressive load, it exhibits elastic properties and will substantially return to its original position after the load is removed. Compression set is sometimes used to help describe this elastic recovery. When pressure is applied to an elastomeric structure, the structure may exhibit elastomeric properties and then recover to near its original position upon relaxation.

The term "extensible" refers to materials that are generally capable of being extended or otherwise deformed, but do not recover a significant portion of their shape upon removal of an extending or deforming force.

The term "flexible" refers to the ability of a material to bend under an applied load such that its flexural modulus at 0.5 millimeter deflection is 1000 grams/millimeter or less as measured by the flexural modulus test.

The term "thermoplastic" describes a material that softens and/or flows when exposed to heat and which substantially returns to its original, hardened condition when cooled to room temperature.

As used herein, "weight percent" or "weight percent". Unless otherwise indicated,% "refers to the weight percent of a particular component, based on the total weight of the composition in which the component is included. For example, if the mixture contains three pounds of sand and one pound of sugar, the weight of sand is 75% (3 pounds of sand per 4 pounds of total mixture) and 25% by weight of sugar.

The term "crystalline", if used, refers to a polymer or segment having a first order transition or crystalline melting point (Tm) as determined by Differential Scanning Calorimetry (DSC) or equivalent technique. The term is used interchangeably with the term "semicrystalline". The term "amorphous" refers to a polymer that has no crystalline melting point as determined by Differential Scanning Calorimetry (DSC) or equivalent technique.

As used herein, melt flow rate ("MFR") can be determined according to ASTM D1238 at 230 ℃ and 2.16kg weight.

As used herein, melt index ("MI") or melt flow index/index, which may also be referred to as melt flow rate, may be determined according to ASTM D1238 at 190 ℃ and 2.16kg weight.

Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

The thermoplastic elastomer composition may comprise a polymer blend. The polymer blend may comprise a non-crosslinked elastomer, an oil, a polyethylene, and an antioxidant.

Preferred styrenic block copolymers are those having the following formulae, respectively: ABA, (A-B) nX, ABAB ', or ABA ' B ', wherein A and A ' represent poly (monovinyl aromatic) blocks and B ' represent hydrogenated poly (conjugated diene) blocks, wherein n is an integer ≧ 2 and wherein X is the remainder of the coupling agent. It is to be understood that blocks a and a ' and B ', respectively, are the same or different from each other, wherein block a is larger than block a ' and block B is larger than B ' or B and B ' are equal.

The most preferred block copolymers have the formula ABA or (a-B) nX wherein a represents one or more monomers selected from styrene, C1-C4 alkylstyrene and C1-C4 dialkylstyrene and especially styrene, alpha-methylstyrene, o-or p-methylstyrene, 1, 3-dimethylstyrene, p-tert-butylstyrene or mixtures thereof, most preferably styrene only, wherein B represents a polymer block of one or more conjugated diene monomers comprising from 4 to 8 carbon atoms, such as 1, 3-butadiene, 2-methyl-1, 3-butadiene (isoprene), 2, 3-dimethyl-1, 3-butadiene or mixtures thereof, preferably butadiene or isoprene, most preferably butadiene.

Preferred block copolymers ABA or (A-B) nX comprise substantially pure poly (styrene) blocks, each having a true molecular weight in the range from 3kg/mol to 50kg/mol, and a total apparent molecular weight in the range from 70 to 700kg/mol, preferably from 100 to 500 kg/mol. The molecular weights referred to in the specification and claims may be measured by Gel Permeation Chromatography (GPC) using polystyrene calibration standards, for example according to ASTM 3536. GPC is a well-known method in which polymers are separated according to molecular size, with the largest molecule eluting first. The chromatograph was calibrated using commercially available polystyrene molecular weight standards. The molecular weight of the polymer measured using GPC so calibrated is the apparent molecular weight, also known as styrene equivalent molecular weight. When the styrene content of the polymer and the vinyl content of the diene segment are known, the styrene equivalent molecular weight can be converted to true molecular weight. The detector used is preferably a combination of ultraviolet and refractive index detectors. The molecular weights expressed herein are measured at the peak of the GPC trace, converted to true molecular weights, and are commonly referred to as "peak molecular weights". Methods for preparing such polymers can be found in U.S. patent No.5,200,200. 3,231,635, U.S. patent. 3,231,635, U.S. patent. 3,231,635, U.S. patent. 3,231,635 and U.S. patent. U.S. patent No. 3,231,635. No. 3,231,635. U.S. patent No. 3,231,635. U.S. patent No. 3,231,635. And in us patent No. 3,231,635. Methods for the selective hydrogenation of the B block are known, for example: U.S. patent No. 3,231,635. U.S. patent No. 3,231,635. U.S. patent No. 3,231,635. Us patent No. 3,231,635 and us patent. No. 3,231,635. The disclosures of these aforementioned documents are incorporated herein by reference.

Suitable representatives of the most preferred block copolymers are under the trade nameSEPTON^TMAnd TUFTEC^TMThose obtained, for example, KRATON G1650, KRATON G1654, KRATON G1651, KRATON G1652, KRATON G1633, KRATON G1641, KRATON G1657, KRATON a 1535, KRATON a 1636, KRATON GRP 6924, SEPTON 4055, SEPTON 4077, TUFTEC H1272, TSRC Taipol 6150, Taipol 6156, Taipol610T, Taipol 6156, Taipol610T, Taipol 6156, Taipol poly (conjugated diene) blocks are hydrogenated until less than 10% of the original ethylenic unsaturation.

The block copolymer useful in this embodiment may be selected from the group consisting of styrene-ethylene-butylene-styrene (SEBS), styrene-ethylene-propylene-styrene (SEPS), hydrogenated polybutadiene, hydrogenated polyisoprene, hydrogenated styrene-isoprene random copolymer, styrene-ethylene-propylene (SEP) block copolymer, styrene-ethylene-propylene-styrene (SEEPS), and hydrogenated styrene-butadiene random copolymer.

Authors EW Duck, JR Hawkins and JM Locke describe in Journal of the IRI,6,19,1972 the hydrogenation of random diene copolymers which can be used as highly saturated elastomers in the present invention and are incorporated herein by reference. Saturated triblock polymers SEBS and SEPS, with styrene end blocks as saturated elastomers, are also used in the present invention. SEBS and SEPS are obtained by hydrogenation of triblock copolymers of styrene and butadiene or styrene and isoprene, and are known to be commercially available. Some commercially available examples of such elastomers include Kraton G series polymers. U.S. patent No. 3, 686, 364 and U.S. patent. Examples of some block copolymers that can be used in the practice of the present invention are given in US 3,865,776, which is incorporated herein by reference. It is highly preferred that the highly saturated elastomer be SEBS with a bound styrene content in the range of 15 wt.% to about 60 wt.%.

Saturated block copolymers that are modified versions of SEBS may be used. Such modified block copolymers additionally have a large number of styrene units randomly distributed in the rubber midblock of ethylene and butylene. These modified saturated block copolymers are supplied in the Kraton 'A' series. The saturated block copolymer grades mentioned in TPE 2003RAPRA Conference Proceedings, Brussels, Belgium, 9 months 16-17 days 2003, Paper 18, page 157 and Paper 21, page 181, may also be used and are incorporated herein by reference.

In one embodiment, the polystyrene-ethylene-butadiene-styrene (SEBS) block copolymer may comprise a suitable SEBS copolymer comprising a total SEBS copolymer having a block styrene content of about 10 wt% to about 35 wt%, and having a shore a hardness value of about 40 to about 80.

The thermoplastic elastomer may comprise from about 0.1 wt% to about 40 wt% polyethylene, more preferably from about 1.0 wt% to about 35 wt% polyethylene, more preferably from 3.0 wt% to about 30 wt% polyethylene, more preferably from 4.0 wt% to about 25 wt% polyethylene, suitable polyethylenes may include High Density Polyethylene (HDPE), Low Density Polyethylene (LDPE) and Linear Low Density Polyethylene (LLDPE). In one embodiment, high molecular weight polyvinyl compounds may be used. In one embodiment, suitable Linear Low Density Polyethylenes (LLDP) generally have a melt index of about 0.5 to about 10.0g/10 minutes, measured at 230 ℃, using a 2.16 kilogram (kg) weight.

The thermoplastic elastomer composition may comprise up to about 60 wt.% oil, preferably from about 15 wt.% to about 55 wt.% oil, more preferably from about 15 wt.% to about 50 wt.% oil, for example. Suitable oils may include mineral oils. Suitable mineral oils may include paraffinic oils (ASTM D2226 TYPE 104) or naphthenic oils (ASTM 103& 104A). All the above oils represent different fractions from the distillation of crude oil.

Further, the thermoplastic elastomer composition may comprise up to about 2 wt.%, preferably up to about 1 wt.% antioxidant, more preferably up to about 0.5 wt.% antioxidant. Suitable antioxidants may include hindered phenols, thiol compounds, amines, or phosphites.

The thermoplastic elastomer composition may also comprise up to about 3 weight percent of a colorant. Suitable color pigments are known to those skilled in the art, and the exact amount of color pigment can be readily determined empirically based on the desired color characteristics of the composition and finished product.

The thermoplastic elastomer composition may also contain up to about 3 weight percent, preferably about 1 weight percent, of a processing aid such as a metal stearate, soap, ultra-high molecular weight siloxane polymer or lubricant to assist in proper flow of the polymer melt through the injection molding barrels and molds and to produce molded parts with good surface characteristics.

The thermoplastic elastomer composition may also optionally comprise stabilizers, such as heat stabilizers and/or light stabilizers, such as ultraviolet light stabilizers, and combinations of heat and light stabilizers. Thermal stabilizers, such as antioxidants, including phenols, amines, phosphites, and the like, as well as combinations comprising at least one of the foregoing thermal stabilizers. Light stabilizers include low molecular weight (number average molecular weight less than about 1,000AMU) benzophenones or hindered amines, high molecular weight (number average molecular weight greater than about 1,000AMU) hindered amines, benzotriazoles, hydroxyphenyl triazines, and the like, as well as combinations comprising at least one of the foregoing light stabilizers. Optionally, various additives known in the art may be used as needed to impart various properties to the composition, such as thermal stability, stability upon exposure to ultraviolet wavelength radiation, long term durability, and processability. The exact amount of stabilizer can be readily determined empirically by the reaction employed and the desired characteristics of the final product, up to about 3% by weight, and preferably 1% by weight.

The thermoplastic elastomer composition and articles formed therefrom may be prepared in one process. In the present process, a polymer blend composed of a thermoplastic elastomer material, such as styrene-ethylene-butadiene-styrene (SEBS) polymer in powder form, is pre-mixed with polyethylene, antioxidants and oil using a high shear mixer or other such device to form a tumble-mixed blend of the composition prior to placing the composition in the hopper of a twin screw extruder through which the pre-blend is melted, mixed and pelletized into thermoplastic elastomer pellets. The formed thermoplastic elastomer can be processed into different products, such as wine bottle stoppers, toothpicks and the like, by an extrusion process, an injection molding process and other polymer processing processes.

Details of the experiment

Mixing in a continuous process typically occurs in a twin screw extruder that is raised to a temperature sufficient to melt the polymer matrix while adding all additives at the feed throat, either by injection or a downstream side feeder. For example, the extruder speed ranges from about 50 to about 1200 revolutions per minute (rpm), preferably from about 300 to about 700 rpm. Typically, the output of the extruder is pelletized for post-processing. The blend components shown below were kneaded at about 160 ℃ to about 220 ℃ by using a twin-screw extruder, and extruded into strands, which were then cut into pellets. For example, a laboratory twin screw extruder comprises 9 zones, wherein zone 1 is about 160 ℃, zone 2 is about 180 ℃, zone 3 is about 210 ℃, zone 4 is about 210 ℃, zone 5 is about 200 ℃, zone 6 is about 180 ℃, zone 7 is about 160 ℃, zone 8 is about 160 ℃, and zone 9 is about 160 ℃. The granulator temperature may be 170 ℃.

Examples 1 to 4

Compositions in the form of granules were prepared using a twin screw extruder according to the compounding recipe shown in table 1 under the conditions discussed in the experimental details. The pellets were injection molded to make square sheets of 10cm by 10 cm. The sheet was cut with a dumbbell cutter to prepare test pieces for measurement. In preparing the composition in a twin screw extruder, the components are dry blended; the blend was passed through an extruder. The results are shown in Table 2.

As is clear from table 2, the elastomer composition of this embodiment is an elastomer having a low compression set, excellent elasticity and excellent dynamic characteristics.

Table 1:

TABLE 2

Summary of test results for groups 14A, 14B, 14C, 1A

Examples 5 to 9

Compositions in the form of granules were prepared using a twin screw extruder under the conditions discussed in the experimental details according to the compounding recipe shown in table 3. The pellets were injection molded to make square sheets of 10cm by 10 cm. The sheet was cut with a dumbbell cutter to prepare test pieces for measurement. In preparing the composition in a twin screw extruder, the components are dry blended; the blend was passed through an extruder. The results are shown in Table 4.

As is clear from table 4, the elastomer composition of this embodiment is an elastomer having low compression set, excellent elasticity and good melt strength.

TABLE 3

Table 4

Embodiments of the compositions, methods, and articles made therefrom of the present invention, while described primarily with respect to wine cork skin applications, may be used in many other applications, including non-automotive and automotive applications, such as interior sheathing, including instrument panel skins, door panels, airbag covers, headliners, and seat covers,

it should be understood that modifications to the embodiments shown herein may be made by those skilled in the art within the scope and intent of the claims. While the invention has been described as being carried out in specific embodiments thereof, the invention is not limited thereto but is intended to be broadly covered within the scope of the claims.

The patents and patent publications cited above are hereby incorporated by reference in their entirety. Although various embodiments have been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other embodiments, modifications and variations, and the like may be ascertained by one of ordinary skill in the pertinent art. It is, therefore, to be understood that the invention may be practiced otherwise than as specifically described.