Foamable compositions and articles

Abstract

The present disclosure relates to a foamable composition and a foamed article formed from the foamable composition. In one embodiment, the foamable composition comprises 50 wt% to 65 wt% of a propylene impact copolymer, 10 wt% to 18 wt% of an ethylene elastomer having a density of 0.860 g / cc to 0.89 g / cc and a melt index of 1 g / 10 min to 50 g / 10 min, 10 wt% to 18 wt% of a propylene elastomer having a density of 0.860 g / cc to 0.890 g / cc and a melt flow rate of 1 g / 10 min to 50 g / 10 min, 0 wt% to 15 wt% of a filler, and 0.5 wt% to 5.0 wt% of a blowing agent. The foamed article formed from the foamable composition has a density of 0.800 g / cc to 0.850 g / cc and an Izod Notched Impact Strength at 23°C of greater than 11 KJ / m 2 to 27 KJ / m 2 .

Description

Background Technology

[0001] Thermoplastic polyolefins (TPOs) are a major component used in automotive interior parts. Examples of automotive interior parts utilizing TPOs include dashboards, door panels, pillars, and bumpers.

[0002] A persistent goal in the automotive industry is vehicle body "lightweighting" in an effort to achieve higher fuel mileage and consequently lower CO2 emissions. Replacing conventional TPO automotive interior components with foam components is one possible approach for vehicle body lightweighting. However, existing TPO formulations for automotive interior components do not readily translate into foam components. Existing TPO formulations, during foaming, fail to achieve the balance between toughness (as measured by cantilever beam notched impact strength) and stiffness (as measured by flexural modulus) required for automotive interior component applications.

[0003] There is a need in the art for TPO formulations that, when forming foamed articles, maintain the same or better balance of toughness and stiffness as existing non-foamed TPO formulations used for automotive interior components. Summary of the Invention

[0004] This disclosure relates to foamable compositions and foam articles formed from the foamable compositions. In one embodiment, the foamable composition comprises 50 wt% to 65 wt% of a propylene impact copolymer, 10 wt% to 18 wt% of an ethylene elastomer with a density of 0.860 g / cc to 0.89 g / cc and a melt index of 1 g / 10 min to 50 g / 10 min, 10 wt% to 18 wt% of a propylene elastomer with a density of 0.860 g / cc to 0.890 g / cc and a melt flow rate of 1 g / 10 min to 50 g / 10 min, 0 wt% to 15 wt% of a filler, and 0.5 wt% to 5.0 wt% of a blowing agent.

[0005] This disclosure also provides foam articles formed from the foamable composition. The foam articles formed from the foamable composition have a density of 0.800 g / cc to 0.850 g / cc and a density greater than 11 KJ / m³. 2 Up to 27KJ / m 2 Impact strength of cantilever beam with notch at 23℃. Attached Figure Description

[0006] Figures 1(a), 1(b) and 1(c) are schematic diagrams of the “two” mold opening operations according to the embodiments of this disclosure.

[0007] definition

[0008] All references to the periodic table herein shall refer to the periodic table published and copyrighted by CRC Press, Inc. in 2003. Furthermore, any reference to one or more groups shall refer to one or more groups reflected in such a periodic table using the IUPAC system for group numbering. Unless stated to the contrary, implied by the context, or customary in the art, all parts and percentages are by weight. For the purposes of U.S. patent practice, any patent, patent application, or publication mentioned herein is incorporated herein by reference in its entirety (or its equivalent U.S. version is so incorporated by reference).

[0009] The numerical ranges disclosed herein include all values ​​from the lower limit to the upper limit and including both the lower limit and the upper limit. For ranges containing definite values ​​(e.g., a range of 1 or 2, or 3 to 5, or 6, or 7), any subrange between any two definite values ​​is included (e.g., the range 1 to 7 above includes subranges such as 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6, etc.).

[0010] Unless stated to the contrary, implied by the context or customary in the art, all parts and percentages are by weight, and all test methods are current methods as of the date of this disclosure.

[0011] As used herein, the term "composition" refers to a mixture of materials comprising the composition and reaction and decomposition products formed from the materials of the composition.

[0012] The terms “comprising,” “including,” “having,” and their derivatives are not intended to exclude the presence of any additional components, steps, or procedures, whether or not such components, steps, or procedures are specifically disclosed. For the avoidance of any doubt, unless stated otherwise, all compositions claimed using the term “comprising” may include any additional additives, adjuvants, or compounds, whether polymerized or otherwise. In contrast, the term “substantially constitutes” excludes any other components, steps, or procedures from any subsequently listed scope, except those that are not essential for operability. The term “consisting of” excludes any ingredients, steps, or procedures not specifically described or listed.

[0013] "Elastomer" and similar terms refer to a rubbery polymer that can stretch to at least twice its original length and shrinks back to approximately its original length extremely rapidly when the stretching force is released. In the uncrosslinked state at room temperature using the method of ASTM D638-72, the elastic modulus of the elastomer is about 10,000 psi (68.95 MPa) or less and the elongation is typically greater than 200%.

[0014] "Ethylene elastomer" and similar terms refer to elastomers composed of ethylene-based polymers.

[0015] As used herein, "ethylene-based polymer" is a polymer containing more than 50% by weight of polymerizable ethylene monomer (in terms of the total amount of polymerizable monomers) and optionally may contain at least one comonomer.

[0016] As used herein, the term "foam" or "foam article" refers to a structure constructed of a polymer that comprises multiple discrete cavities or foam pores completely surrounded by the polymer. As used herein, the term "foam pore" or "pore" is a discrete space within a foam composition. Foam pores are separated or otherwise defined by membrane walls composed of the polymers of the foam composition.

[0017] As used herein, "olefin polymer" or "polyolefin" is a polymer containing more than 50% by weight of polymerizable olefin monomers (based on the total amount of polymerizable monomers) and optionally may contain at least one comonomer. Non-limiting examples of olefin-based polymers include ethylene-based polymers and propylene-based polymers.

[0018] "Polymer" is a compound prepared by polymerizing monomers, whether of the same or different types, that provide in polymeric form multiple and / or repeating "units" or "monomer units" constituting the polymer. Therefore, the general term polymer encompasses the term homopolymer, which is generally used to refer to polymers prepared from only one type of monomer, and the term copolymer, which is generally used to refer to polymers prepared from at least two types of monomers. The general term polymer also encompasses all forms of copolymers, such as random copolymers, block copolymers, etc. The terms "ethylene / α-olefin polymer" and "propylene / α-olefin polymer" refer to copolymers prepared, as described above, by polymerizing ethylene or propylene and one or more other polymerizable α-olefin monomers, respectively. It should be noted that although polymers are often referred to as being "made" from one or more specific monomers, "based on" a specific monomer or monomer type, "containing" a specific monomer content, etc., in this context, the term "monomer" should be understood as referring to the polymeric residue of a specific monomer, not an unpolymerized species. Generally, polymers in this document refer to "units" based on the polymeric form of the corresponding monomer.

[0019] "Propylene-based elastomers" (or "PBE") include reactor-grade propylene-based polymers with a heat of fusion of less than about 100 J / g and a MWD of less than 3.5. PBE typically has a heat of fusion of less than about 40 J / g. PBE has a weight percentage of ethylene from 3 wt% to 15 wt%.

[0020] "Propylene-based polymers" are polymers containing more than 50% by weight of polymerizable propylene monomers (in terms of the total amount of polymerizable monomers) and optionally may contain at least one comonomer.

[0021] Test methods

[0022] Differential scanning calorimetry (DSC)

[0023] Differential scanning calorimetry (DSC) can be used to measure the melting, crystallization, and glass transition behavior of polymers over a wide temperature range. For example, this analysis is performed using a TA Instruments Q1000DSC equipped with an RCS (refrigerated cooling system) and an autosampler. During testing, a nitrogen purge gas flow of 50 ml / min is used. Each sample is melt-pressed into a thin film at approximately 175°C; the molten sample is then cooled to room temperature (approximately 25°C). 3–10 mg of a 6 mm diameter sample is drawn from the cooled polymer, weighed, placed in a light aluminum pan (approximately 50 mg), and rolled up. Analysis is then performed to determine its thermal properties.

[0024] The thermal behavior of the sample was determined by creating a heat flow versus temperature curve through ramping and ramping the sample temperature. First, the sample was rapidly heated to 180°C and held isothermally for 3 minutes to remove its thermal history. Next, the sample was cooled to -40°C at a cooling rate of 10°C / min and held isothermally at -40°C for 3 minutes. Then, the sample was heated back to 180°C at a heating rate of 10°C / min (this is the "second heating" ramp). The cooling and heating curves were recorded. The cooling curve was analyzed by setting a baseline endpoint from the start of crystallization to -20°C. The heating curve was analyzed by setting a baseline endpoint from -20°C to the end of melting. The measured values ​​are the extrapolated melting initiation temperature Tm and the extrapolated crystallization initiation temperature Tc. The heat of fusion (Hf) (in joules / gram) and the crystallinity % of the polyethylene sample were calculated using the following equation: Crystallinity % = ((Hf / gram) / Tc = (Hf / Tc ... f (292J / g)×100

[0025] Heat of fusion (H) f (Also known as melting enthalpy) and peak melting temperature are reported by the second thermal profile.

[0026] The melting point Tm is determined from the DSC heating curve by first plotting a baseline between the beginning and end of the melt transition. Then, a tangent is plotted on the data at the low-temperature side of the melt peak. The point where this tangent intersects the baseline is the extrapolated starting point of the melt (Tm). This is as described in Bernhard Wunderlich, *The Basis of Thermal Analysis, in Thermal Characterization of Polymeric Materials*, 92, 277-278 (Edited by Edith A. Turi, 2nd ed., 1997).

[0027] The glass transition temperature (Tg) was determined by DSC heating curves of half of the samples, for which the liquid heat capacity had been obtained, as described by Bernhard Wunderlich, *Thermal Analysis Fundamentals in Thermal Characterization of Polymer Materials*, 92, 278-279 (Edited by Edith A. Turi, 2nd ed., 1997). Baselines were plotted below and above the glass transition region and extrapolated through the Tg region. The temperature at the midpoint between these baselines is the sample heat capacity.

[0028] The density of foam products is measured according to ASTM D-1622-88, with results given at 25°C in kg / m³. 3 Reports should be submitted in units of grams per cubic centimeter (g / cc).

[0029] The density of the polymer was measured according to ASTM D792, with results reported in g / cc at 25°C.

[0030] Flexural modulus and flexural yield strength were measured according to ASTM 0790-970. Results were recorded in megapascals or MPa.

[0031] Melt flow rate (or MFR) measurements are performed according to ASTM D1238, at 230°C and with a 2.16 kg weight (for propylene-based elastomers). Similar to the melt index, melt flow rate is inversely proportional to the polymer's molecular weight. Therefore, although the relationship is not linear, higher molecular weights generally result in lower melt flow rates.

[0032] Melt index (MI or I2) (for ethylene-based elastomers) is measured according to ASTM D 1238, under conditions of 190°C / 2.16 kg, with results reported in grams per 10 minutes (g / 10 min).

[0033] The notched impact strength of the cantilever beam was measured according to ISO 180 at 23°C and -30°C, with results expressed as kJ / m².2 )Report.

[0034] Tensile strength. The compositions of the present invention can be characterized by their tensile strength at break (in MPa) and elongation at break (%). Tensile strength and elongation at break are measured on compression-molded specimens prepared according to ASTM D4703 according to the ASTM D638 test procedure. Elongation at break, or elongation at break, is the strain at which the specimen breaks, expressed as a percentage.

[0035] As used herein, the term "pore size" is a measure of the size of foam pores. Pore size is determined by dividing the average pore count by a specified length and multiplying the result by 1.62, a geometric factor determined for this purpose, as disclosed in Cellular Polymers, Vol. 21, No. 3, pp. 165-194 (2002). Pore size (i.e., average pore size) is measured according to ASTM D3576-77 and reported in micrometers.

[0036] The Vicat softening point is measured according to ASTM D 1525, where the results are reported in degrees Celsius (°C). Detailed Implementation

[0037] This disclosure provides a foamable composition. The foamable composition comprises 50 wt% to 65 wt% of a propylene impact copolymer and 10 wt% to 18 wt% of an ethylene elastomer. The ethylene elastomer has a density of 0.860 g / cc to 0.890 g / cc and a melt index of 1 g / 10 min to 50 g / 10 min. The foamable composition further comprises 10 wt% to 18 wt% of a propylene elastomer. The propylene elastomer has a density of 0.860 g / cc to 0.890 g / cc and a melt flow rate of 1 g / 10 min to 50 g / 10 min. The foamable composition also comprises 0 wt% to 15 wt% of filler and 0.5 wt% to 5.0 wt% of a blowing agent.

[0038] As used herein, the term “foamable composition” is a mixture of (i) propylene impact copolymer, (ii) ethylene elastomer, (iii) propylene elastomer, (iv) optional filler and (v) foaming agent under extrusion conditions.

[0039] The foamable composition comprises a propylene impact copolymer. The propylene impact copolymer is a two-phase polymer in which a discrete domain of the rubber phase (or discontinuous phase) of the ethylene / propylene copolymer is dispersed throughout the matrix phase (or continuous phase) of the propylene homopolymer. Based on the total weight of the propylene impact copolymer, the propylene impact copolymer comprises 5 wt% to 15 wt%, or 7 wt% to 13 wt%, or 8 wt% to 11 wt% of the ethylene / propylene rubber phase.

[0040] In one embodiment, the propylene impact copolymer has one, some, or all of the following properties:

[0041] (i) an ethylene / propylene rubber phase ranging from 7 wt% to 13 wt%, or from 8 wt% to 11 wt%; and / or

[0042] (ii) a density of 0.89 g / cc to 0.91 g / cc; and / or

[0043] (iii) MFR of 50 g / 10 min to 70 g / 10 min, or 55 g / 10 min to 65 g / 10 min; and / or

[0044] (iv) Vicat softening point of 140°C to 170°C or 150°C to 160°C.

[0045] A non-limiting example of a suitable propylene impact copolymer is BX 3900, which is available from SK Global Chemical Company.

[0046] The foamable composition comprises an ethylene elastomer. The ethylene elastomer is an ethylene / α-olefin copolymer that is either an ethylene / propylene copolymer or an ethylene / C4-C8 α-olefin copolymer. In one embodiment, the ethylene elastomer is an ethylene / α-olefin copolymer that is either an ethylene / C4-C8 α-olefin copolymer or a copolymerizable C4-C8 α-olefin copolymer. The ethylene / C4-C8 α-olefin copolymer is composed of polymeric ethylene and a copolymerizable C4-C8 α-olefin comonomer, or otherwise composed of these components. The C4-C8 α-olefin comonomer is selected from butene, hexene, and octene. The ethylene / C4-C8 α-olefin copolymer has a density of 0.860 g / cc to 0.89 g / cc, or 0.860 g / cc to 0.880 g / cc; a melt index of 1 g / 10 min to 50 g / 10 min, or 3 g / 10 min to 20 g / 10 min, or 4 g / 10 min to 15 g / 10 min; and a melting point (Tm) of 40°C to 60°C, or 50°C to 60°C.

[0047] In one embodiment, the ethylene elastomer is an ethylene / octene copolymer having one, some, or all of the following properties:

[0048] (i) a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; and / or

[0049] (ii) Melt index of 3 g / 10 min to 20 g / 10 min, or 4 g / 10 min to 15 g / 10 min; and / or

[0050] (iii) Tm at 50°C to 60°C; and / or

[0051] (iv) Tg from -60°C to -50°C; and / or

[0052] (v) Vicat softening point at 30°C to 40°C.

[0053] Non-limiting examples of suitable ethylene elastomers include ENGAGE 8137 and ENGAGE 8200, available from Dow, Inc.

[0054] The foamable composition comprises a propylene elastomer. The propylene elastomer is a propylene / α-olefin copolymer as a propylene / ethylene copolymer. The propylene / ethylene copolymer consists of propylene and ethylene comonomers in polymeric form or otherwise constitutes them. Based on the total weight of the propylene / ethylene copolymer, the propylene / ethylene copolymer contains 3 wt% to 15 wt%, or 5 wt% to 15 wt%, or 7 wt% to 13 wt% units derived from ethylene. The propylene / ethylene copolymer has a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; an MFR of 1 g / 10 min to 50 g / 10 min, or 5 g / 10 min to 30 g / 10, or 15 g / 10 min to 30 g / 10 min; and a Tm of 60°C to 90°C, or 62°C to 87°C.

[0055] In one embodiment, the propylene elastomer is a propylene / ethylene copolymer having 7 wt% to 13 wt% ethylene-derived units based on the total weight of the propylene / ethylene copolymer, and the propylene / ethylene copolymer has one, some, or all of the following properties:

[0056] (i) a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; and / or

[0057] (ii) MFR of 15 g / 10 min to 30 g / 10 min; and / or

[0058] (iii) Tm between 60°C and 90°C or between 62°C and 87°C; and / or

[0059] (iv) Vicat softening point from 45°C to 55°C.

[0060] Non-limiting examples of suitable propylene elastomers include VERSIFY 4200 and VERSIFY 4301, available from Dow Chemical.

[0061] The foamable composition of the present invention may contain optional fillers. When fillers are present in the foamable composition, fillers are selected from talc, calcium carbonate, mica, glass fiber, and combinations thereof. In one embodiment, the foamable composition contains 0 wt%, or more than 0 wt%, or 1 wt%, or 5 wt% to 10 wt%, or 20 wt%, or 30 wt% of filler.

[0062] In one embodiment, the filler is talc and is present in an amount greater than 0 wt% to 15 wt%, or 5 wt% to 15 wt%, or 8 wt% to 12 wt% based on the total weight of the foamable composition.

[0063] The expandable composition contains a blowing agent. The blowing agent can be a physical blowing agent or a chemical blowing agent. As used herein, the term "physical blowing agent" is a compound or composition that (i) is sufficiently dissolved in the expandable composition under extrusion conditions and in the polymer composition (or supercritical phase) under those conditions, and (ii) exits from solution under the conditions (temperature, pressure) encountered during the formation of the foam composition as the expandable composition leaves the extrusion die. Under extrusion conditions, a physical blowing agent is added to the polymer composition to form the expandable composition. Non-limiting examples of suitable physical blowing agents include N2 gas and / or CO2 gas.

[0064] In one embodiment, the foaming agent is a chemical foaming agent. The chemical foaming agent produces one or more physical foaming agents through thermal decomposition during the foaming process. Chemical foaming agents include (but are not limited to) sodium bicarbonate, sodium borohydride, azodicarbonamide, azobisisobutyronitrile, barium azodicarboxylate, N,N′-dimethyl-N,N′-dinitrosoterephthalamide and benzenesulfonylhydrazine, 4,4-oxybenzenesulfonamide and p-toluenesulfonamide, trihydrazine triazine, and mixtures such as citric acid and sodium bicarbonate.

[0065] In one embodiment, the chemical foaming agent is selected from sodium bicarbonate and sodium borohydride.

[0066] The foamable composition may contain one or more optional additives. When additives are present, non-limiting examples of suitable additives include pigments (carbon black, titanium dioxide), antioxidants, acid scavengers, UV stabilizers (e.g., hindered amine stabilizers such as N,N′-bisformyl-N,N′-bis(2,2,6,6-tetramethyl-4-piperidinyl)-hexamethylenediamine), flame retardants, processing aids, extrusion aids, antistatic agents, and combinations thereof.

[0067] In one embodiment, the foamable composition of the present invention comprises an antioxidant. Non-limiting examples of suitable antioxidants include bis(4-(1-methyl-1-phenylethyl)phenyl)amine; 2,2′-thiobis(2-tert-butyl-5-methylphenol); 2,2′-thiobis(6-tert-butyl-4-methylphenol); tris[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)methyl]-1,3,5-triazine-2,4,6-trione; pentaerythritol tetrakis(3-(3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)propionate distearate (“DSTDP”); dilauryl thiodipropionate; or 2′,3-bis[[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]]propionylhydrazine]. The antioxidant is present in an amount of 0.1 wt% to 0.5 wt% based on the total weight of the foamable composition.

[0068] In one embodiment, the foamable composition comprises:

[0069] (A) 50wt% to 65wt% of propylene impact copolymer;

[0070] (B) 10 wt% to 18 wt% of ethylene elastomer having a density of 0.860 g / cc to 0.890 g / cc and a melt index of 1 g / 10 min to 50 g / 10 min;

[0071] (C) 10 wt% to 18 wt% of a propylene elastomer having a density of 0.860 g / cc to 0.890 g / cc and an MFR of 1 g / 10 min to 50 g / 10 min;

[0072] (D) 0 wt%, or 1 wt% to 15 wt% of filler; and

[0073] (E) 1.0 wt% to 5.0 wt% of a foaming agent, wherein the total of components (A)-(E) is 100 wt% of the foamable composition.

[0074] In one embodiment, the foamable composition comprises:

[0075] (A) 52wt% to 60wt% of a propylene impact copolymer, wherein the propylene impact copolymer has

[0076] (i) 7 wt% to 13 wt% of ethylene / propylene rubber phase; and / or

[0077] (ii) a density of 0.89 g / cc to 0.91 g / cc; and / or

[0078] (iii) MFR of 50 g / 10 min to 70 g / 10 min; and / or

[0079] (iv) Vicat softening point from 140°C to 170°C;

[0080] (B) 12 wt% to 18 wt% of ethylene elastomer, wherein the ethylene elastomer has

[0081] (i) densities ranging from 0.860 g / cc to 0.89 g / cc; and / or

[0082] (ii) MI of 3 g / 10 min to 20 g / 10 min; and / or

[0083] (iii) Tm between 50°C and 60°C; and / or

[0084] (iv) Tg from -60°C to -50°C; and / or

[0085] (v) Vicat softening point at 30°C to 40°C;

[0086] (C) 12wt% to 18wt% of propylene elastomer, wherein the propylene elastomer has

[0087] (i) a density of 0.860 g / cc to 0.870 g / cc; and / or

[0088] (ii) MFR of 15 g / 10 min to 30 g / 10 min; and / or

[0089] (iii) Tm between 60°C and 90°C; and / or

[0090] (iv) Vicat softening point at 45°C to 55°C;

[0091] (D) 5wt% to 15wt% of filler;

[0092] (E) 1.0 wt% to 5.0 wt% of a foaming agent; and

[0093] (F) 0.1 wt% to 0.5 wt% of antioxidant, the total of components (A)-(F) being 100 wt% of the foamable composition.

[0094] In one embodiment, the foamable composition comprises:

[0095] (A) 55 wt% to 60 wt% of a propylene impact copolymer, wherein the propylene impact copolymer has

[0096] (i) 7 wt% to 13 wt% of ethylene / propylene rubber phase; and / or

[0097] (ii) a density of 0.89 g / cc to 0.91 g / cc; and / or

[0098] (iii) MFR of 50 g / 10 min to 70 g / 10 min; and / or

[0099] (iv) Vicat softening point from 140°C to 170°C;

[0100] (B) 12 wt% to 18 wt% of ethylene elastomer, wherein the ethylene elastomer has

[0101] (i) densities ranging from 0.860 g / cc to 0.89 g / cc; and / or

[0102] (ii) MI of 3 g / 10 min to 20 g / 10 min; and / or

[0103] (iii) Tm at 50°C to 60°C: and / or

[0104] (iv) Tg from -60°C to -50°C; and / or

[0105] (v) Vicat softening point at 30°C to 40°C;

[0106] (C) 12wt% to 18wt% of propylene elastomer, wherein the propylene elastomer has

[0107] (i) a density of 0.860 g / cc to 0.870 g / cc; and / or

[0108] (ii) MFR of 15 g / 10 min to 30 g / 10 min; and / or

[0109] (iii) Tm between 60°C and 90°C; and / or

[0110] (iv) Vicat softening point at 45°C to 55°C;

[0111] (D) 8wt% to 12wt% of filler;

[0112] (E) 1.0 wt% to 5.0 wt% of foaming agent: and

[0113] (F) 0.1 wt% to 0.5 wt% of antioxidant, the total of components (A)-(F) being 100 wt% of the foamable composition.

[0114] The foamable composition contains or excludes silanes and / or crosslinking agents.

[0115] A foamable composition ((i) a propylene impact copolymer, (ii) an ethylene elastomer, (iii) a propylene elastomer, (iv) optional fillers, (v) a blowing agent, and (vi) optional additives) is subjected to a foaming process, whereby the foamable composition is melt-mixed in an extruder to melt the polymer and dissolve the blowing agent into the molten mixture. The molten mixture is then injected into an injection mold. Upon injection into the mold, the mold volume rapidly increases, causing a rapid drop in pressure inside the mold, which triggers the molten mixture to expand into foam. This foam expands and fills the increased volume inside the mold, thereby forming a foamed article. The foamed article consists of or is otherwise formed from the foamable composition.

[0116] This disclosure provides foam articles produced from the foamable compositions of the present invention. In one embodiment, the foam article comprises:

[0117] (A) 50wt% to 65wt% of propylene impact copolymer;

[0118] (B) 10 wt% to 18 wt% of ethylene elastomer having a density of 0.860 g / cc to 0.890 g / cc and a melt index of 1 g / 10 min to 50 g / 10 min;

[0119] (C) 10 wt% to 18 wt% of a propylene elastomer having a density of 0.860 g / cc to 0.890 g / cc and an MFR of 1 g / 10 min to 50 g / 10 min;

[0120] (D) 0 wt%, or 1 wt% to 15 wt% of filler; and the total of components (A)-(D) is 100 wt% of the foamed product, and the foamed product has one, some, or all of the following properties:

[0121] (1) Density from 0.800 g / cc to 0.850 g / cc; and / or

[0122] (2) Greater than 11 KJ / m at 23℃ 2 Up to 27KJ / m 2 The notched impact strength of the cantilever beam; and / or

[0123] (3) No cross-linking (no gel content); and / or

[0124] (4) It contains or excludes silanes or silicon (hereinafter referred to as Foam 1).

[0125] In one embodiment, the foam article comprises:

[0126] (A) 52wt% to 60wt% of a propylene impact copolymer, wherein the propylene impact copolymer has

[0127] (i) 7 wt% to 13 wt% of ethylene / propylene rubber phase; and / or

[0128] (ii) a density of 0.89 g / cc to 0.91 g / cc; and / or

[0129] (iii) MFR of 50 g / 10 min to 70 g / 10 min; and / or

[0130] (iv) Vicat softening point from 140°C to 170°C;

[0131] (B) 12 wt% to 18 wt% of ethylene elastomer, wherein the ethylene elastomer has

[0132] (i) a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; and / or

[0133] (ii) MI of 3 g / 10 min to 20 g / 10 min; and / or

[0134] (iii) Tm between 50°C and 60°C; and / or

[0135] (iv) Tg from -60°C to -50°C; and / or

[0136] (v) Vicat softening point at 30°C to 40°C;

[0137] (C) 12wt% to 18wt% of propylene elastomer, wherein the propylene elastomer has

[0138] (i) a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; and / or

[0139] (ii) MFR of 15 g / 10 min to 30 g / 10 min; and / or

[0140] (iii) Tm between 60°C and 90°C; and / or

[0141] (iv) Vicat softening point at 45°C to 55°C;

[0142] (D) 5wt% to 15wt% of filler; and

[0143] (E) 0.1 wt% to 0.5 wt% of an antioxidant, the total of components (A)-(E) being 100 wt% of the foam product, and the foam product having one, some, or all of the following properties:

[0144] (1) A density of 0.810 g / cc to 0.850 g / cc, or 0.810 g / cc to 0.840 g / cc; and / or

[0145] (2) Greater than 11 KJ / m at 23℃ 2 Up to 27KJ / m 2 The notched impact strength of the cantilever beam; and / or

[0146] (3) 2.5 to 4.0 KJ / m at -30℃ 2 The notched impact strength of the cantilever beam; and / or

[0147] (4) Flexural modulus greater than 600 MPa to less than 1100 MPa; and / or

[0148] (5) No cross-linking (no gel content); and / or

[0149] (6) It contains or excludes silanes or silicon (hereinafter referred to as Foam 2).

[0150] In one embodiment, the foam article comprises:

[0151] (A) 55 wt% to 60 wt% of a propylene impact copolymer, wherein the propylene impact copolymer has

[0152] (i) 7 wt% to 13 wt% of ethylene / propylene rubber phase; and / or

[0153] (ii) a density of 0.89 g / cc to 0.91 g / cc; and / or

[0154] (iii) MFR of 50 g / 10 min to 70 g / 10 min; and / or

[0155] (iv) Vicat softening point from 140°C to 170°C;

[0156] (B) 12 wt% to 18 wt% of ethylene elastomer, wherein the ethylene elastomer has

[0157] (i) a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; and / or

[0158] (ii) MI of 3 g / 10 min to 20 g / 10 min; and / or

[0159] (iii) Tm between 50°C and 60°C; and / or

[0160] (iv) Tg from -60°C to -50°C; and / or

[0161] (v) Vicat softening point at 30°C to 40°C;

[0162] (C) 12wt% to 18wt% of propylene elastomer, wherein the propylene elastomer has

[0163] (i) a density of 0.860 g / cc to 0.890 g / cc, or 0.860 g / cc to 0.880 g / cc; and / or

[0164] (ii) MFR of 15 g / 10 min to 30 g / 10 min; and / or

[0165] (iii) Tm between 60°C and 90°C; and / or

[0166] (iv) Vicat softening point at 45°C to 55°C;

[0167] (D) 8wt% to 12wt% of filler; and

[0168] (E) 0.1 wt% to 0.5 wt% of an antioxidant, the total of components (A)-(E) being 100 wt% of the foam product, and the foam product having one, some, or all of the following properties:

[0169] (1) A density of 0.810 g / cc to 0.850 g / cc, or 0.810 g / cc to 0.840 g / cc; and / or

[0170] (2) Greater than 11 KJ / m at 23℃ 2 Up to 27KJ / m 2 The notched impact strength of the cantilever beam; and / or

[0171] (3) 2.5 to 4.0 KJ / m at -30℃ 2 The notched impact strength of the cantilever beam; and / or

[0172] (4) Flexural modulus greater than 600 MPa to less than 1100 MPa; and / or

[0173] (5) No cross-linking (no gel content); and / or

[0174] (6) Contains or excludes silanes or silicon (hereinafter referred to as foam 3).

[0175] Foam articles (foam 1 and / or foam 2 and / or foam 3) formed from the foamable compositions of the present invention can be extruded sheets, rods, plates, films, and profiles. In one embodiment, the foam articles (foam 1 and / or foam 2) formed from the foamable compositions of the present invention are used in automotive interior components. Non-limiting examples of automotive interior components in which foam articles (foam 1 and / or foam 2 and / or foam 3) are components include door panels, steering wheels, seats, dashboards, instrument panels, glove boxes, center consoles, interior trim components, and combinations thereof.

[0176] In one embodiment, this disclosure provides a vehicle, such as a car or truck, comprising a foamed article (foam 1 and / or foam 2 and / or foam 3) formed from the foamable composition of the present invention.

[0177] Some embodiments of this disclosure are described in detail in the following examples, not as limiting ones.

[0178] Example

[0179] The raw materials used in the examples (“IE”) and comparative samples (“CS”) of this invention are detailed in Table 1 below.

[0180] Table 1: Materials

[0181]

[0182]

[0183] Foam preparation

[0184] Weigh each component and extrude each component (except the foaming agent) using a Coperon 18mm extruder. Granulate the polymer material into small pellets using a side-cutting granulator to form TPO pellets. Dry-blend the TPO pellets with the foaming agent. Inject the dried TPO pellet blend into a FANUC S-2000I B series injection molding machine with a diameter of 28mm. Set the profile temperature to 200°C and the mold temperature to 95°C. As shown in Figures 1(a), 1(b), and 1(c), apply a "two-stage" mold opening operation, starting from a 1mm opening distance in the foaming space.

[0185] Table 2. Formulation of expandable compositions and properties of the resulting foam products .

[0186]

[0187]

[0188] Properties -- For each formulation, two foam compositions with different blowing agents are produced.

[0189] *-The first values ​​for each property are for foam compositions made with 1.5 wt% Hydrocel J001 blowing agent.

[0190] The second value for each property is for foam compositions made with 4 wt% Ewai EE25C blowing agent.

[0191] CS-comparison sample

[0192] IE - Invention Embodiments

[0193] The applicant discovered that adding acrylic elastomers (Versify 4200 and / or Versify 4301) to TPO formulations achieved unexpected toughness (greater than 11 KJ / m). 2 Up to 27KJ / m 2 Foam products that balance cantilever beam notch (23°C) and stiffness (flexural modulus greater than 600MPa to less than 1100MPa).

[0194] It is particularly desirable that this disclosure is not limited to the embodiments and descriptions contained herein, but includes modifications of those embodiments, including portions of embodiments appearing within the scope of the following claims and combinations of elements of different embodiments.

Claims

1. A foamable composition comprising: 55 wt% to 60 wt% of a propylene impact copolymer, said propylene impact copolymer having (i) 7 wt% to 13 wt% ethylene / propylene rubber phase; (ii) Density ranging from 0.89 g / cc to 0.91 g / cc; (iii) Melt flow rate of 50 g / 10 min to 70 g / 10 min; and (iv) Vicat softening point from 140°C to 170°C; 12 wt% to 18 wt% ethylene elastomer, said ethylene elastomer having (i) Densities ranging from 0.860 g / cc to 0.89 g / cc; (ii) Melt index from 3 g / 10 min to 20 g / 10 min; (iii) Melting point between 50°C and 60°C; (iv) Glass transition temperature from -60°C to -50°C; and (v) Vicat softening point at 30°C to 40°C; 12wt% to 18wt% of propylene elastomer, wherein the propylene elastomer is a propylene / ethylene copolymer and has (i) Densities ranging from 0.860 g / cc to 0.890 g / cc; (ii) Melt flow rate from 15 g / 10 min to 30 g / 10 min; (iii) Melting point between 60°C and 90°C; and (iv) Vicat softening point at 45°C to 55°C; 8 wt% to 12 wt% of filler; and 1.0wt% to 5.0wt% of foaming agent.

2. The foamable composition according to claim 1, wherein the ethylene elastomer has (i) Densities ranging from 0.860 g / cc to 0.880 g / cc; (ii) Melt index of 4 g / 10 min to 15 g / 10 min; (iii) Melting point between 50°C and 60°C; (iv) Glass transition temperature from -60°C to -50°C; and (v) Vicat softening point at 30°C to 40°C.

3. The foamable composition according to any one of claims 1-2, wherein the propylene elastomer is a propylene / ethylene copolymer and has (i) Densities ranging from 0.860 g / cc to 0.880 g / cc; (ii) Melt flow rate from 15 g / 10 min to 30 g / 10 min; (iii) Melting point between 62°C and 87°C; and (iv) Vicat softening point from 45°C to 55°C.

4. The foamable composition according to any one of claims 1-2, wherein the foaming agent is selected from sodium bicarbonate, sodium borohydride, azodicarbonamide, azobisisobutyronitrile, barium azodicarboxylate, N,N'-dimethyl-N,N'-dinitrosoterephthalamide, benzenesulfonylhydrazine, 4,4-oxybenzenesulfonamide, p-toluenesulfonamide, trihydrazine, and combinations thereof.

5. A foam article formed from the composition according to any one of claims 1-4, said foam article having: (1) Density ranging from 0.800 g / cc to 0.850 g / cc; and (2) Greater than 11 KJ / m at 23℃ 2 Up to 27KJ / m 2 Impact strength of the cantilever beam notch.

6. The foam product according to claim 5, comprising: (3) 2.5 to 4.0 KJ / m at -30℃ 2 The impact strength of the cantilever beam with notch; and (4) Young's modulus greater than 600 MPa to less than 1100 MPa.

7. The foam article according to claim 5 or 6, wherein the foam article (5) No cross-linking; and (6) Contains no silicon.

8. The foam article according to claim 5 or 6, wherein the foam article is an automotive interior component selected from door panels, steering wheels, seats, dashboards, instrument panels, glove boxes, center consoles, and combinations thereof.

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