Silicone-thermoplastic compositions and hybrid elastomers

Abstract

Provided is a silicone-thermoplastic composition. The silicone-thermoplastic composition has a continuous phase containing a first polysiloxane and a discontinuous phase containing a thermoplastic polymer dispersed within the continuous phase. Also provided is a method for preparing said silicone-thermoplastic composition.

Description

SILICONE-THERMOPLASTIC COMPOSITIONS AND HYBRID ELASTOMERS FIELD OF THE INVENTION

[0001] The present invention relates to silicone compositions and, more specifically, to a siliconethermoplastic composition and a method for preparing the silicone -thermoplastic composition, and silicone-thermoplastic hybrid elastomers formed with the silicone-thermoplastic composition.INTRODUCTION

[0002] Polysiloxanes (also known as silicones) are valuable for their excellent elastomeric properties compared to thermoplastic polymers. However, polysiloxanes generally exhibit lower mechanical strength (such as tear strength) compared to carbon-based thermoplastic polymers (hereinafter “thermoplastic polymers”). Additionally, the cost of polysiloxanes is higher than thermoplastic polymers, which limits their broader applications. As such, there is strong interest in developing polysiloxane-based hybrid elastomers by integrating thermoplastic polymers into polysiloxanes while preserving inherent elastomeric properties of the original poly siloxanes.

[0003] Silicone-polyolefin hybrid elastomers (“SiPOs”) have been previously reported. However, the service temperature of SiPOs is constrained by the relatively low melting temperature of polyolefins. For example, polyethylenes typically have a melting temperature (Tm) less than 140 °C. The low melting temperature of polyolefins inhibit SiPOs’ use in applications requiring high-temperature performance. Thus, there is an interest in incorporating thermoplastic polymers that have melting temperatures higher than polyolefins (hereinafter, “high-melting-temperature thermoplastic polymers”) into polysiloxanes to increase the resulting service temperature range of the mixture.

[0004] SiPOs are typically prepared through reactive compatibilization. Reactive compatibilization can be an effective strategy for forming hybrid polymer systems. However, reactive compatibilization involves chemical reactions between functional groups on the polymers and reactive compatibilizers. Therefore, its effectiveness depends on the availability of suitable compatibilizers and reactive functional groups on the polymers. Many high-melting-temperature thermoplastic polymers such as polyesters lack sufficient reactive functionalities, making this approach challenging for blending high-melting-temperature thermoplastic polymers into poly siloxanes.

[0005] Accordingly, there is a need for a polysiloxane -based hybrid elastomer that incorporates a high-melting-temperature thermoplastic polymers dispersed within a polysiloxane continuous phase. Preferably, the polysiloxane-based hybrid elastomers exhibit elastomeric properties (such as elongation at break) that are comparable to, or even superior to, those of the polysiloxane continuous phase alone. It is further desirable for these polysiloxane -based hybrid elastomers toexhibit tear strength and / or tensile strength properties that are comparable to or even greater than those of the polysiloxane continuous phase alone.BRIEF SUMMARY OF THE INVENTION

[0006] The present invention provides a silicone-thermoplastic composition comprising high-melting-temperature thermoplastic polymers dispersed within a polysiloxane matrix, as well as methods for preparing the silicone-thermoplastic composition. The process of the present invention enables effective dispersion of high-melting -temperature thermoplastic polymers within a polysiloxane continuous phase even when the high-melting-temperature thermoplastic polymers lack reactive functional groups or even when reactive compatibilizers are not present. Furthermore, when cured, the silicone-thermoplastic compositions exhibit elastomeric properties that are comparable to, and in some cases exceed, those of the original polysiloxanes. In certain examples, the cured silicone-thermoplastic compositions demonstrated tear strength and / or tensile strength values that are comparable to or greater than those of the cured continuous phase polysiloxane alone.

[0007] In a first aspect, the present invention is a silicone -thermoplastic composition. The silicone-thermoplastic composition comprises: (A) a continuous phase comprising: (i) a first polysiloxane, wherein the first poly siloxane has a Williams’s plasticity value in a range of 30 to 250 millimeters (mm) / 100 as determined by ASTM D926 at 25 °C or wherein the first polysiloxane has a viscosity value in a range of 50 to 100,000 millipascal-second (mPa-s) as determined according to ASTM-D2196 at 25 °C; and (ii) optionally, fillers; and (B) a discontinuous phase dispersed within the continuous phase (A), wherein the discontinuous phase (B) comprises: (i) a thermoplastic polymer comprising a high-melting-temperature thermoplastic polymer selected from polyesters, polyoxymethylenes, a polyamides, and any combination thereof; and (ii) optionally, a second polysiloxane comprising an average of at least one silicon-bonded functional group X per molecule, where each of the silicon-bonded functional group X is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, carbinol functional groups, and combinations thereof; wherein, when the high-melting-temperature thermoplastic polymer (B)(i) comprises a polyamide, the discontinuous phase (B) optionally comprises (iii) a polyolefin comprising an average of at least one functional group Y per molecule, wherein each of the functional group Y is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, and combinations thereof.

[0008] In a second aspect, the present invention is a method for preparing the siliconethermoplastic composition of the first aspect. The method for preparing the silicone -thermoplastic composition comprises the following steps:(a) mixing the first polysiloxane (A)(i) and the high-melting-temperature thermoplastic polymer (B)(i) at an elevated temperature greater than the melting temperature of the high-melting-temperature thermoplastic polymer (B)(i), optionally in the presence of the fillers (A)(ii), the second polysiloxane (B)(ii), the polyolefin (B)(iii), or combinations thereof, to give a mixture; and(b) reducing the elevated temperature of the mixture to a reduced temperature less than the melting temperature of the high-melting-temperature thermoplastic polymer (B)(i) and thereby producing the silicone-thermoplastic composition of the first aspect.

[0009] Additional features and advantages are in the detailed description that follows. The herein-described silicone-thermoplastic composition, and the method for preparing thereof, deliver a cost-effective solution for producing polysiloxane-based hybrid elastomeric products that combine the elastomeric properties (such as elongation at break) of poly siloxanes with mechanical strengths (such as tear strength and / or tensile strength) of high-temperature thermoplastic polymers.DETAILED DESCRIPTION OF THE INVENTION

[0010] Definitions

[0011] An expression of the form “Cx-Cy” or “Cx.y” refers to a carbon atom -containing chemical group having from x to y carbon atoms, inclusive of x and y. For example, the term “C1-C20 alkyl group” refers to an alkyl group containing 1 to 20 carbon atoms.

[0012] All ranges include endpoints unless otherwise stated.

[0013] Test methods herein refer to the most recent test method as of the priority date of this document when a date is not indicated with the test method number. References to test methods contain both a reference to the testing society and the test method number when possible. ASTM International is abbreviated as ASTM.

[0014] Trademarks refer to materials sold under that trademark on the priority date of this document.

[0015] Silicone-Thermoplastic Composition

[0016] The silicone-thermoplastic composition comprises: (A) a continuous phase comprising: (i) a first polysiloxane and (ii) optionally, fillers; and (B) a discontinuous phase dispersed within the continuous phase (A), wherein the discontinuous phase (B) comprises: (i) a thermoplastic polymer comprising a high-melting-temperature thermoplastic polymer selected from polyesters, polyoxymethylenes, polyamides, and any combinations thereof. Optionally, the discontinuousphase (B) may comprise (ii) a second polysiloxane comprising an average of at least one silicon-bonded functional group X per molecule, where each of the silicon-bonded functional group X is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, carbinol functional groups, and combinations thereof. Optionally, when the high-melting-temperature thermoplastic polymer (B)(i) comprises a polyamide, the discontinuous phase (B) may further comprise (iii) a polyolefin comprising an average of at least one functional group Y per molecule, where each of the functional group Y is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, and combinations thereof.

[0017] The silicone-thermoplastic composition may be provided as a non-curing masterbatch or a curable composition. A composition is considered “non-curing” when it is free of curing agent, such as a platinum-group metal based catalyst, an organic peroxide, or a condensation catalyst. Conversely, a composition is “curable” when it includes a curing agent. The silicone -thermoplastic composition may additionally include a crosslinking agent, an inhibitor agent, or combinations thereof. When present, the curing agent, the crosslinking agent, and the inhibitor agent are present in the Continuous Phase (A) of the silicone -thermoplastic composition.

[0018] (A) Continuous Phase

[0019] The continuous phase (A) constitutes the predominant component of the siliconethermoplastic compositions. The term “predominant” means that the continuous phase (A) is present in an amount of 50 weight percent (wt.%) or more, 55 wt.% or more, 60 wt.% or more, 65 wt.% or more, 70 wt.% or more, 75 wt.% or more, 80 wt.% or more, 85 wt.% or more, 90 wt.% or more, or 95 wt.% or more, while at the same time is present in an amount of 99 wt.% or less, 95 wt.% or less, 90 wt.% or less, 85 wt.% or less, 80 wt.% or less, 75 wt.% or less, 70 wt.% or less, 65 wt.% or less, 60 wt.% or less, or 55 wt.% or less, with wt.% values being relative to the weight of the silicone-thermoplastic composition. Preferably, the continuous phase (A) is present in an amount in a range of 55 to 95 wt.% or 65 to 95 wt.%, relative to the weight of the siliconethermoplastic composition.

[0020] (A)(i) First Polysiloxane

[0021] As used herein, the term “polysiloxane” refers to a polymer containing repeating siloxane units (-Si-O-Si-). Each silicon atom in the siloxane units may be bonded to a substituent group (R) or another siloxane unit, and polysiloxane may be linear, branched or resinous.

[0022] The First Polysiloxane (A)(i) contains R groups. For First Polysiloxane (A)(i), the R groups are not limited in the broadest scope of the invention. For example, each R for First Polysiloxane (A)(i) can be a hydrogen atom, an alkyl group, an aryl group, a halogen substituted alkyl group, or a functional group. The functional groups for First Polysiloxane (A)(i) may be selected from, alkenyl groups, alkynyl groups, silanol groups, and alkoxy groups. For example, First Polysiloxane (A)(i) may comprise at least two or more functional groups selected from alkenyl groups and alkynyl groups, such as from C2-C10 alkenyl groups and C2-C10 alkynyl groups, or from C2-C4 alkenyl groups. Exemplary halogen substituted alkyl group includes 3,3,3-trifluoropropyl.

[0023] First Polysiloxane (A)(i) is present in an amount of 35 wt.% or more, 40 wt.% or more, 45 wt.% or more, 50 wt.% or more, 55 wt.% or more, 60 wt.% or more, 65 wt.% or more, 70 wt.% or more, 75 wt.% or more, 80 wt.% or more, 85 wt.% or more, 90 wt.% or more, or 95 wt.% or more, while at the same time is present in an amount of 100 wt.% or less, 99.5 wt.% or less, 95 wt.% or less, 90 wt.% or less, 85 wt.% or less, 80 wt.% or less, 75 wt.% or less, 70 wt.% or less, 65 wt.% or less, 60 wt.% or less, 55 wt.% or less, 50 wt.% or less, 45 wt.% or less, or 40 wt.% or less, with wt.% values being relative to the weight of the continuous phase (A). Preferably, First Polysiloxane (A)(i) is present in an amount of 55 to 99.5 wt.%, or 55 to 85 wt.% , with wt.% values being relative to the weight of the continuous phase (A).

[0024] First Polysiloxane (A)(i) may be a polysiloxane gum. Polysiloxane gum typically has a high molecular weight that it is non-flowable and is not considered as a fluid or a liquid at 25 °C. First Polysiloxane (A)(i), when is a polysiloxane gum, has a William’s plasticity in a range of 30 to 250 mm / 100, and can be 30 mm / 100 or more, 40 mm / lOOor more, 50 mm / 100 or more, 60 mm / 100 or more, 70 mm / 100 or more, 80 mm / 100 or more, 90 mm / 100 or more, 100 mm / 100 or more, 110 mm / 100 or more, 120 mm / 100 or more, 130 mm / 100 or more, 140 mm / 100 or more, 150 mm / 100 or more, 160 mm / 100 or more, 170 mm / 100 or more, 180 mm / 100 or more, 190 mm / 100 or more, 200 mm / 100 or more, 210 mm / 100 or more, 220 mm / 100 or more, 230 mm / 100 or more, or 240 mm / 100 or more, while at the same time can be 250 mm / 100 or less, 240 mm / 100 or less, 230 mm / 100 or less, 220 mm / 100 or less, 210 mm / 100 or less, 200 mm / 100 or less, 190 mm / 100 or less, 180 mm / 100 or less, 170 mm / 100 or less, 160 mm / 100 or less, 150 mm / 100 or less, 140 mm / 100 or less, 130 mm / 100 or less, 120 mm / 100 or less, 110 mm / 100 or less, 100 mm / 100 or less, 90 mm / 100 or less, 80 mm / 100 or less, 70 mm / 100 or less, 60 mm / 100 or less, 50 mm / 100 or less, or 40 mm / 100 or less, as determined by ASTM D926. The William’s plasticity, as used herein, is defined as the thickness in millimeters / 100 of a cylindrical test specimen (2 cubic centimeters (cm1) in volume and approximately 10 mm in height) after the specimen has been subjected to a compressive load of 49 Newtons for three minutes at 25 degrees Celsius (°C).Preferably, the plasticity number is from 100 mm / 100 to 220 mm / 100, most preferably about 130 mm / 100 to 200 mm / 100.

[0025] First Polysiloxane ( A)(i) may be in a liquid form and flowable at 25 °C. First Polysiloxane (A)(i), when is in a liquid form, has a viscosity of 50 mPa-s or more, 100 mPa-s or more, 250 mPa-s or more, 500 mPa-s or more, 750 mPa-s or more, 1,000 mPa-s or more, 2,500 mPa-s or more, 5,000 mPa-s or more, 7,500 mPa-s or more, 10,000 mPa-s or more, 20,000 mPa-s or more, 30,000 mPa-s or more, 40,000 mPa-s or more, or 50,000 mPa-s or more, while at the same time 100,000 mPa-s or less, 75,000 mPa-s or less, 50,000 mPa-s or less, 40,000 mPa-s or less, 30,000 mPa-s or less, 20,000 mPa-s or less, 10,000 mPa-s or less, 7,500 mPa-s or less, 5,000 mPa-s or less, 2,500 mPa- s or less, 1 ,000 mPa- s or less, 750 mPa- s or less, 500 mPa- s or less, 250 mPa- s or less, or 100 mPa-s or less, as determined according to ASTM-D2196 at 25 °C.

[0026] (A)(ii) Optional Fillers

[0027] Thus, the continuous phase (A) may optionally comprise fillers (ii). The fillers (ii) may be reinforcing fillers. Reinforcing fillers may comprise silicas, calcium carbonates, or combinations thereof. Examples of suitable reinforcing fillers include silica (such as fumed silica, colloidal silica, and precipitated silica) and calcium carbonate (such as precipitated calcium carbonate and ground calcium carbonate). The typical surface area for the reinforcing fillers has a value of at least 15 square meters per gram (m2 / g), determined by the Brunauer-Emmett-Teller method in accordance with ISO 9277 : 2010. For example, precipitated calcium carbonate may have a surface area value in a range of 15 to 50 m2 / g, and fumed silica may have a surface area value of at least 50 m2 / g, such as in a range of 75 to 250 m2 / g. The particle size of the reinforcing fillers is usually less than 50 nanometers (nm). For example, fumed silica may have a particle size in a range of 10 to 25 nm. Fillers (A)(ii) may be surface treated in accordance with U.S. Patent No. 12,025,258 B2.

[0028] Fillers (A)(ii), may be present in an amount, relative to the weight of the continuous phase (A), in a range of 0 to 60 wt.%, and can be 0 wt.% or more, 5 wt.% or more, 10 wt.% or more, 15 wt.% or more, 20 wt.% or more, 25 wt.% or more, 30 wt.% or more, 35 wt.% or more, 40 wt.% or more, 45 wt.% or more, 50 wt.% or more, or 55 wt.% or more, while at the same time 60 wt.% or less, 55 wt.% or less, 50 wt.% or less, 45 wt.% or less, 40 wt.% or less, 35 wt.% or less, 30 wt.% or less, 25 wt.% or less, 20 wt.% or less, 15 wt.% or less, 10 wt.% or less, or 5 wt.% or less. Preferably, Fillers (A)(ii) are present in an amount of 0 to 60 wt.% or 0 to 45 wt.% or 10 to 45 wt.%.

[0029] The continuous phase (A) may optionally further comprise any one or any combination of more than one of the following: (iii) a curing agent; (iv) a crosslinking agent; and (v) an inhibitor agent.

[0030] (A)(iii) Optional Curing Agent

[0031] Curing Agent (A)(iii) may comprise a platinum-group metal based catalyst, an organic peroxide compound, a tin(II) compound, a tin(IV) compound, or a titanium compound.

[0032] Curing Agent ( A)(iii) may comprise a platinum-group metal based catalyst. Examples of platinum-group metal based catalysts include Pt complex with 1 ,3 -di vinyl- 1, 1,3,3-tetramethyldisiloxane (Karstedt’s catalyst), Pt complex in tetramethyltetravinylcyclotetrasiloxane (Ashby’s catalyst), chloroplatinic acid (Speier’s catalyst), chloroplatinic acid in alcohol solution (Lamoreaux catalyst), and chloridotris(triphenylphosphine)rhodium(I) (Wilkinson’s catalyst).

[0033] Curing Agent ( A)(iii) may comprise an organic peroxide compound. Examples of organic peroxide-functionalized compounds include diaroyl peroxides such as benzoyl peroxide, dibenzoyl peroxide, di-p-chlorobenzoyl peroxide, and bis-2,4-dichlorobenzoyl peroxide; dialkyl peroxides such as di-t-butyl peroxide, lauroyl peroxide, and 2,5-dimethyl-2,5-di-(t-butylperoxy)hexane; diaralkyl peroxides such as dicumyl peroxide; alkyl aralkyl peroxides such as t-butyl cumyl peroxide and l,4-bis(t-butylperoxyisopropyl)benzene; alkyl aryl peroxides such as t-butyl perbenzoate, t-butyl peracetate, t-butyl peroctoate, t-butyl peroxybenzoate, and t-amyl peroxybenzoate; carbonate peroxides such as t-butylperoxy isopropyl carbonate; hydroperoxides such as cumen hydroperoxide and t-butyl hydroperoxide; peracids such as peracetic acid; and ketone peroxides such as cyclohexanone peroxide.

[0034] Curing Agent (A)(iii) may comprise a condensation catalyst. Examples of condensation catalysts include tin(II) and tin(IV) compounds (such as tin dilaurate, tin dioctoate, and tetrabutyl tin) and titanium compounds (such as titanium tetrabutoxide).

[0035] Curing Agent (A)(iii) is present in an amount of 0 wt.% or more, 0.5 wt.% or more, 1 wt.% or more, 1.5 wt.% or more, 2 wt.% or more, 2.5 wt.% or more, 3 wt.% or more, 3.5 wt.% or more, 4 wt.% or more, 4.5 wt.% or more, while at the same time is present in an amount of 5 wt.% or less, 4.5 wt.% or less, 4 wt.% or less, 3.5 wt.% or less, 3 wt.% or less, 2.5 wt.% or less, 2 wt.% or less, 1.5 wt.% or less, 1 wt.% or less, 0.5 wt.% or less, with wt.% values being relative to the weight of the continuous phase (A).

[0036] (A)(iv) Optional Crosslinking Agent

[0037] When Curing Agent (A)(iii) comprises a platinum-group metal based catalyst, the continuous phase (A) desirably also comprises Crosslinking Agent (iv). When Curing Agent (A)(iii) comprises an organic peroxide compound, the continuous phase (A) can optionally also comprise Crosslinking Agent (iv).

[0038] Crosslinking Agent (A)(iv) may comprise a hydrosiloxane, a hydrosilane, an alkenyl-functionalized silane, an alkenyl-functionalized siloxane, an alkynyl-functionalized silane, an alkynyl-functionalized siloxane, an alkoxysilane, or combinations thereof.

[0039] Hydrosiloxanes are siloxanes containing at least one silicon-bonded hydrogen atom. Hydrosiloxanes may also be linear, branched or resinous. Examples of hydrosiloxanes include hydrogenpolysiloxanes (homopolymers or copolymers) containing silicon-bonded hydrogen atom in an amount in a range of 0.2 to 1.8 wt.%, and can be 0.2 wt.% or more, 0.4 wt.% or more, 0.6 wt.% or more, 0.8 wt.% or more, 1.0 wt.% or more, 1.2 wt.% or more, 1.4 wt.% or more, 1.6 wt.% or more, while at the same time can be 1.8 wt.% or less, 1.6 wt.% or less, 1.4 wt.% or less, 1.2 wt.% or less, 1.0 wt.% or less, 0.8 wt.% or less, 0.6 wt.% or less, 0.4 wt.% or less, determined as the weight of SiH relative to the weight of the hydrogenpolysiloxane. Preferably, the hydrogenpolysiloxanes contain 0.6 to 1.0 wt.%. of silicon-bonded hydrogen atoms, determined as the weight of SiH relative to the weight of the hydrogenpolysiloxane.

[0040] Examples of hydrosilanes include trimethylsilane, methylhydrogendichlorosilane, phenylsilane, diphenylsilane, and trichlorosilane.

[0041] Examples of alkenyl-functionalized silanes include ViaSi, PhSiVis, MeSi Vi;,, PhMeSi Vi2. Ph2SiVi2. and PhSi(CHaCH=CH2)3, wherein Me is methyl, Ph is phenyl, and Vi is vinyl. Examples of alkenyl-functionalized siloxanes include PhSi(OSiMeaVi)3, Si(OSiMeaVi)4, MeSilOSiMeaVi)?,. and Ph2Si(OSiMe2Vi)2, wherein Me is methyl, Vi is vinyl, and Ph is phenyl.

[0042] Examples of alkynyl-functionalized silanes include vinyltris(isopropenyloxy)silane, phenyltris(isopropenyloxy)silane, ethynyl-functional silanes (such as 3-methyl-3-penten-l-yne silane, 3-phenyl-3-buten-l-yne silane, and their derivatives), bis(trimethylsilyl)-l,3-butadiyne, and phenylethynyltrimethoxysilane.

[0043] Examples of alkynyl-functionalized siloxanes include propargyl-Modified polydimethylsiloxanes, ethynyl-Terminated polydimethylsiloxanes, bis(alkynyl)-functional siloxane, phenylethynyl-substituted siloxanes, and vinyl / alkynyl siloxane copolymers.

[0044] Examples of alkoxysilanes include MeSi(OCH3)3, CH3Si(OCH2CH3)3, CH3Si(OCH2CH2CH3)3, CH3Si[O(CH2)3CH3]3, CH3CH2Si(OCH2CH3)3, C6H5Si(OCH3)3, C6H5CH2Si(OCH3)3, C6H5Si(OCH2CH3)3, CH2=CHSi(OCH3)3, CH2=CHCH2Si(OCH3)3, CF3CH2CH2Si(OCH3)3, CH3Si(OCH2CH2OCH3)3, CF3CH2CH2Si(OCH2CH2OCH3)3, CH2=CHSi(OCH2CH2OCH3)3, CH2=CHCH2Si(OCH2CH2OCH3)3, C6H5Si(OCH2CH2OCH2)3, Si(OCH3)4. Si(OC2H5)4, and Si(OC3H7)4.

[0045] Crosslinking Agent (A)(iv) is present in an amount in a range of 0 to 2 wt.%, and can be 0 wt.% or more, 0.2 wt.% or more, 0.4 wt.% or more, 0.6 wt.% or more, 0.8 wt.% or more, 1.0 wt.% or more, 1.2 wt.% or more, 1.4 wt.% or more, 1.6 wt.% or more, 1.8 wt.% or more, while at the same time can be 2.0 wt.% or less, 1.8 wt.% or less, 1.6 wt.% or less, 1.4 wt.% or less, 1.2wt.% or less, 1.0 wt.% or less, 0.8 wt.% or less, 0.6 wt.% or less, 0.4 wt.% or less, or 0.2 wt.% or less, with wt.% values relative to the weight of the continuous phase (A).

[0046] (A)(v) Optional Inhibitor Agent

[0047] Inhibitor Agent (A)(v) may comprise an acetylenic alcohol, an alkenyl-functionalized silane, an alkenyl-functionalized siloxane, an alkynyl-functionalized silane, an alkynyl-functionalized siloxane, a dicarboxylic acid or an ester thereof, ethynylalkenes, or combinations thereof. For example, Inhibitor Agent (A)(v) may comprise 1-ethynyl-l -cyclohexanol (ETCH), 3,5-Dimethyl-l-hexyn-3-ol, l-methyl-3-butyn-2-ol, phenyl butynol, tetramethyl tetravinyl cyclotetrasiloxane, methyl(tris( 1 , 1 -dimethyl-2-propynyloxy))silane, bis-(2-methoxy- 1 -methylethyl) maleate, dially maleate, diethyl fumerate, dimethyl acetylenedicarboxylate (DMAD), 3-methyl-3-penten-l-yne, 3-methyl-3-hexen-l-yne, 3,5-dimethyl-3-hexen-l-yne, 3-ethyl-3-buten-l-yne, 3-phenyl-3-buten-l-yne, or combinations thereof.

[0048] Inhibitor Agent (A)(v) may be present in an amount in a range of 0 to 2.0 wt.%, and can be 0 wt.% or more, 0.2 wt.% or more, 0.4 wt.% or more, 0.6 wt.% or more, 0.8 wt.% or more, 1.0 wt.% or more, 1.2 wt.% or more, 1.4 wt.% or more, 1.6 wt.% or more, 1.8 wt.% or more, while at the same time can be 2.0 wt.% or less, 1.8 wt.% or less, 1.6 wt.% or less, 1.4 wt.% or less, 1.2 wt.% or less, 1.0 wt.% or less, 0.8 wt.% or less, 0.6 wt.% or less, 0.4 wt.% or less, or 0.2 wt.% or less, with wt.% values being relative to the weight of the continuous phase (A).

[0049] (B) Discontinuous Phase

[0050] Discontinuous phase (B) may be present in an amount in a range of 1 to 50 wt.%, and can be 1 wt.% or more, 5 wt.% or more, 10 wt.% or more, 15 wt.% or more, 20 wt.% or more, 25 wt.% or more, 30 wt.% or more, 35 wt.% or more, 40 wt.% or more, or 45 wt.% or more, while at the same time 50 wt.% or less, 45 wt.% or less, 40 wt.% or less, 35 wt.% or less, 30 wt.% or less, 25 wt.% or less, 20 wt.% or less, 15 wt.% or less, 10 wt.% or less, or 5 wt.% or less, with wt.% values being relative to the weight of the silicone-thermoplastic composition. Preferably, the discontinuous phase (B) is present in an amount in a range of 1 to 45 wt.% or 5 to 35 wt.%, with wt.% values being relative to the weight of the silicone-thermoplastic composition.

[0051] (B)(i) Thermoplastic Polymer

[0052] Discontinuous phase (B) comprises High-Melting-Temperature Thermoplastic Polymer (B)(i). For the purpose of this invention, High-Melting-Temperature Thermoplastic Polymer (B)(i) is a thermoplastic polymer having a melting temperature higher than 140 °C and is desirably selected from polyesters, polyoxymethylenes, polyamides, and combinations thereof. For the purposes of this invention, the term “melting temperature” is not limited to the solid-liquid phase transition temperature but is broadly interpreted as the temperature at which the polymertransitions from a solid-like state to a liquid-like state, recognizing that amorphous polymers may lack a distinct solid-liquid transition unlike crystalline or semi-crystalline polymers.

[0053] “Liquid-like state” means visibly flowable. “Visibly flowable” means exhibiting a melt mass-flow rate (MFR) or a melt volume -flow rate (MVR) measurable in accordance with ISO 1133. For example, all DURACON™ polyoxymethylene resin grades have a melting temperature in a range of 162-167 °C and a MFR value in a range of 2.5 to 27 grams per 10 minutes (g / 10 min), measured at 190 °C under a 2.16 kg load in accordance with ISO 1133. Commercially available polyethylene terephthalate (PET) resins typically have an MFR value in a range of 20 to 40 g / 10 min and an MVR value in a range of 8 to 20 cubic centimeter per 10 minutes (cm3 / 10 min), measured at 250 °C under a 2.16 kg load in accordance with ISO 1133 or ASTM D1238.

[0054] “ Solid-like state” means not visibly flowable or does not have a melt mass-flow rate (MFR) or a melt volume-flow rate (MVR) measurable in accordance with ISO 1133.

[0055] High-Melting-Temperature Thermoplastic Polymer (B)(i) may be a homopolymer selected from polyamides, polyesters, and polyoxymethylenes or a copolymer comprising polyamides, polyesters, polyoxymethylenes, or combinations thereof. A copolymer refers to a polymer formed from two or more different monomer species that are chemically incorporated into the same polymer chain. Copolymers can exhibit various architectures, including random, alternating, block, and graft structures. In a random copolymer, the different monomers are distributed in a random sequence along the chain; non-limiting examples include hexamethyleneadipamide / caproamide copolymers (Nylon 6 / 66) and polyoxymethylene (POM) copolymers. In an alternating copolymer, monomers alternate in a regular pattern; polyhexamethyleneadipamides (Nylon 6,6), formed from hexamethylene diamine and adipic acid, is an example. Block copolymers consist of large segments (blocks) of one monomer type followed by blocks of another, while graft copolymers comprise a main polymer backbone with side chains (branches) of a different polymer.

[0056] Polyamides, as used herein, broadly include aliphatic polyamides, semi-aromatics, and polyaramides. Aliphatic polyamides primarily consist of linear, non-aromatic hydrocarbon backbones, whereas polyaramides feature backbones that are predominantly aromatic. Incorporation of aromatic rings into polymer backbone generally increases melting temperature, glass transition temperature, and rigidity of the resulting polyamides. Semi-aromatic polyamides, such polyphthalamides, include aromatic rings within part of their backbone structure. Polylphthalamides are polyamides in which 55% or more of the carboxylic acid component in the repeating backbone units is derived from aromatic diacid, such as terephthalic and / or isophthalic acid. Non-limiting examples of polyamides include polylauryllactams, polycaproamides, polyhexamethyleneadipamides, polyundecanoamides, polytetramethyleneadipamides,polyhexamethylenesebacamides, polyxylyleneadipamides, polyhexamethylenedodecamides, polydodecaneamides, polyhexamethylenedodecanediamides, polyhexamethyleneazelamides, polyhexamethyleneterephthalamides, polymetaxylylenediamineadipamides, polyundecaneamides, poly phthalamides, polynonamethyleneterephthalamides, caproamide / hexamethyleneterephthalamide copolymers, hexamethyleneadipamide / caproamide copolymers , hexamethyleneterephthalamide / dodecanamide copolymers, hexamethyleneadipamide / hexamethyleneterephthalamide copolymers, hexamethyleneadipamide / hexamethyleneisophthalamide copolymers, hexamethyleneterephthalamide / hexamethyleneisophthalamide copolymers, hexamethyleneadipamide / hexamethyleneisophthalamide / caproamide copolymers, hexamethyleneadipamide / hexamethyleneterephthalamid / carpoamide copolymers, hexamethyleneterephthalamide / 2-methyl-pentamethyleneterephthalamide copolymers, hexamethyleneadipamide / hexamethyleneterephthalamide / hexamethyleneisophthalamide copolymers, and combinations thereof. The polyamide resin may be an aromatic polyamide (polyaramide).

[0057] Polyesters are synthetic polymers prepared by the reaction of a hydroxyl-functionalized compound with a carboxylic acid or its derivative. The hydroxyl-functionalized compound may be dihydric or polyhydric alcohols, such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1 ,4-pentanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, glycerol, 1,1,1 -trimethylolpropane, 1,1,1 -trimethylolethane, 1,2,6-hexanetriol, decanediol, dodecanediol a-methyl glucoside, pentaerythritol, sorbitol, and 2,2-bis(4-hydroxylphenyl)propane. Examples of carboxylic acids and derivatives include polycarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, 2-methyl-l,6-hexanoic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, brassylic acid, maleic acid, fumaric acid, glutaconic acid, a-hydromuconic acid, -hydromuconic acid, a-butyl-a-ethyl-glutaric acid, a, -diethylsuccinic acid, isophthalic acid, terephthalic acid, hemimellitic acid, phthalic acid, isophthalic acid and 1 ,4-cyclohexanedicarboxylic acid. Examples of polyesters resulting therefrom include, but not limited to, polyethylene terephthalate (PET) or polybutylene terephthalate (PBT).

[0058] Polyesters, as used herein, are not limited to those formed from combinations of hydroxylcontaining compounds and carboxylic acids or their derivatives listed herein. Polyesters may also include liquid crystalline polyesters, which are typically produced from combinations of aromatic and / or aliphatic glycols with aromatic dicarboxylic acid and anhydrides, such as those incorporating monomers derived from 4-hydroxybenzoic acid or its derivatives. Polyesters mayalso include copolyesters such as those comprising the polymerization products of dimethyl terephthalate, cyclohexanedimethanol, and 2,2,4,4-Tetramethyl-l,3-cyclobutanediol.

[0059] Polyoxymethlene (POM), also known as polyacetal or polyformaldehyde, is characterized by repeating -CH2-O- units in its backbone. When High-Melting-Temperature Thermoplastic Polymer (B)(i) comprises a polyoxymethylene, the polyoxymethylene may be a homopolymer having repeating -CH2-O- units in its backbone or a copolymer, in which at least one -CH2-O-unit is replaced with -CH2CH2-O- unit.

[0060] High-Melting-Temperature Thermoplastic Polymer (B)(i) desirably has a melting temperature in a range from 100 to 350 °C, such as 100 °C or higher, 125 °C or higher, 150 °C or higher, 175 °C or higher, 200 °C or higher, 225 °C or higher, 250 °C or higher, 275 °C or higher, while at the same time 300 °C or lower, 275 °C or lower, 250 °C or lower, 225 °C or lower, 200 °C or lower, 175 °C or lower, 150 °C or lower.

[0061] High-Melting-Temperature Thermoplastic Polymer (B)(i) may be present in an amount, relative to the weight of the discontinuous phase (B), in a range of 40 to 100 wt.%, and can be 40 wt.% or more, 45 wt.% or more, 50 wt.% or more, 55 wt.% or more, 60 wt.% or more, 65 wt.% or more, 70 wt.% or more, 75 wt.% or more, 80 wt.% or more, 85 wt.% or more, 90 wt.% or more, or 95 wt.% or more, while at the same time 100 wt.% or less, 95 wt.% or less, 90 wt.% or less, 85 wt.% or less, 80 wt.% or less, 75 wt.% or less, 70 wt.% or less, 65 wt.% or less, 60 wt.% or less, 55 wt.% or less, 50 wt.% or less, or 45 wt.% or less. High-Melting-Temperature Thermoplastic Polymer (B)(i) may be present in an amount in a range of 50 wt.% to 100 wt.%, 65 wt.% to 100 wt.%, or 75wt.% to 100 wt.%, with wt.% values being relative to the weight of the discontinuous phase (B).

[0062] (B)(ii) Optional Second Polysiloxane

[0063] Discontinuous phase (B) optionally comprises a Second Polysiloxane (B)(ii). Second Polysiloxane (B)(ii) may be linear, branched or resinous. Second Polysiloxane (ii) may comprise an average of at least one silicon-bonded functional group X per molecule, where each of the silicon-bonded functional group X is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, carbinol functional groups, and combinations thereof. Second Polysiloxane (B)(ii) is different from First Polysiloxane (A)(i). The viscosity of Second Polysiloxane (B)(ii) is generally lower than that of First Polysiloxane (A)(i).

[0064] Aminoalkyl functional groups include primary amino-substituted alkyl group having from 1 to 20 carbon atoms (for example, aminomethyl, 2-aminoethyl, 3-aminopropyl, and 6-aminohexyl), an aminoaryl group (for example, 4-aminophenyl, and 3 -(4- aminophenyl) propyl),or an aminoalkylamino group (for example, N-(2-aminoethyl)-3-aminopropyl and N-(2-aminoethyl)-3-aminoisobutyl).

[0065] Acryloxy functional groups refer to a reactive moiety having a general formula of (CH2-CR1-C(O)-O-), where R1is a hydrogen atom or an alkyl, such as methyl or ethyl.

[0066] Anhydride functional groups, as used herein, refer to anhydrides of monocarboxylic acids and poly carboxy lie acids. Non-limiting example anhydrides of monocarboxylic acids include acetic anhydride, lactic anhydride, propanoic anhydride, pentanoic anhydride, and methacrylic anhydride. Non-limiting example anhydrides of polycarboxylic acids include succinates (that is, succinic anhydrides), maleates (that is, maleic anhydrides), and phthalates. The anhydrides can be homoanydrides or mixed anhydrides. Mixed anhydrides are anhydrides formed by the condensation of two different carboxylic acids, resulting in an anhydride that contains both acyl groups.

[0067] Olefinically-unsaturated groups include ethylenically unsaturated groups. Examples of ethylenically unsaturated groups generally include substituted or unsubstituted hydrocarbyl groups having at least one alkene or alkyne functional group. For example, in certain embodiments, each functional group X comprises, alternatively is, a C2-C10 alkenyl group, a C2-C4 alkenyl group, a C2-C10 alkynyl group, or a C2-C4 alkynyl group, such as a vinyl group.

[0068] Epoxide groups include, but not limited to, a 3-glycidoxypropyl group, a 4-glycidoxybutyl group, or similar glycidoxyalkyl (i.e., glycidyloxyalkyl) groups; a 2-(3,4-epoxycyclohexyl)ethyl group, a 3-(3,4-epoxycyclohexyl)propyl group, or similar epoxycyclohexylalkyl groups; a 4-oxiranylbutyl group, and an 8-oxiranyloctyl group. Such epoxy groups may be bonded directly to the second polysiloxane (ii). Alternatively, a divalent C2-C10 hydrocarbylene or alternatively C2-C10 alkylene, may be present in X between the epoxide group and the silicon atom to which X is bonded. Specific examples include an epoxy-functionalized polydimethylsiloxane (PDMS) and a glycidoxypropyl-functionalized PDMS having the following chemical structures (I) and (II), respectively:where x = 97.

[0069] Carbinol functional groups, in the context of siloxane chemistry, refer to a hydroxyl group (-OH) bonded to a divalent hydrocarbylene linker, which is in turn bonded to a silicon atom. The divalent hydrocarbylene linker may be a divalent Ci-Cio hydrocarbylene group, such as a divalent Ci-Cio alkylene group.

[0070] Specific examples of Second Polysiloxane (B)(ii) include amine-functionalized polydimethylsiloxanes, vinyl-functionalized polydimethylsiloxanes, methacryloylalkyl-functionalized polydimethylsiloxanes, silanol-functionalized polydimethylsiloxanes, succinic anhydride-functionalized polydimethylsiloxanes, silyl hydride-functionalized polydimethylsiloxanes, epoxy-functionalized polydimethylsiloxanes, maleic anhydride-functionalized polydimethylsiloxanes, carbinol-functionalized polydimethylsiloxanes, and aminoalkyl-functionalized polydimethylsiloxanes.

[0071] The silicone-bonded X functional groups of Second Polysiloxane (B) (ii) may or may not be reactable with High-Melting-Temperature Thermoplastic Polymer (B)(i). For example, when High-Melting-Temperature Thermoplastic Polymer (B)(i) is selected from polyesters, polyoxymethylenes, or combinations thereof, then the silicone-bonded X functional groups may not be reactable with (B)(i), given that polyesters and polyoxymethylenes are generally considered inert. When High-Melting-Temperature Thermoplastic Polymer (B)(i) comprises a polyamide or its combinations with polyesters and / or polyoxymethylenes and / or another polyamide, the silicone-bonded X functional groups may be reactable with High-Melting-TemperatureThermoplastic Polymer (B)(i). For example, polyamides may be reactable with anhydride functional groups and epoxide functional groups.

[0072] Second Polysiloxane (ii) may be a linear polysiloxane. Additionally, Second polysiloxane (ii) may exhibit a viscosity of 50 to 10,000 mPa- s, such as 50 mPa- s or more, 500 mPa- s or more, 1,000 mPa-s or more, 2,000 mPa-s or more, 3,000 mPa-s or more, 4,000 mPa-s or more, 5,000 mPa- s or more, 6,000 mPa-s or more, 7,000 mPa-s or more, 8,000 mPa-s or more, or 9,000 mPa-s or more, while at the same time 10,000 mPa-s or less, 9,000 mPa-s or less, 8,000 mPa-s or less, 7,000 mPa-s or less, 6,000 mPa-s or less, 5,000 mPa-s or less, 4,000 mPa-s or less, 3,000 mPa-s or less, 2,000 mPa-s or less, 1,000 mPa-s or less, or 500 mPa-s or less.

[0073] Second polysiloxane (ii) may be present in an amount in a range of 0 to 60 wt.%, and can be 0 wt.% or more, 5 wt.% or more, 10 wt.% or more, 15 wt.% or more, 20 wt.% or more, 25 wt.% or more, 30 wt.% or more, 35 w.% or more, 40 wt.% or more, 45 wt.% or more, 50 wt.% or more, or 55 wt.% or more, while at the same time can be 60 wt.% or less, 55 wt.% or less, 50 wt.% or less, 45 wt.% or less, 40 wt.% or less, 35 wt.% or less, 30 wt.% or less, 25 wt.% or less, 20 wt.% or less, 15 wt.% or less, 10 wt.% or less, or 5 wt.% or less, with wt.% values being relative to the weight of the discontinuous phase (B). Preferably, Second polysiloxane (ii) is present in an amount in a range of 0 wt.% to 20 wt.%, 2.5 wt.% to 20 wt.%, or 5 wt.% to 20 wt.%

[0074] (B)(iii) Optional Polyolefin

[0075] When (B)(i) comprises a polyamide, the discontinuous phase (B) optionally comprises a polyolefin (B)(iii). Polyolefin (B)(iii) may comprise an average of at least one functional group Y per molecule. Each of the functional group Y independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, and combinations thereof. These functional groups are as defined for functional group Xin (B)(ii). When High-Melting-Temperature Thermoplastic Polymer (B)(i) comprises a polyamide or its combinations with polyesters and / or polyoxymethylenes and / or another polyamide, the functional group Y may be reactable with High-Melting-Temperature Thermoplastic Polymer (B)(i), as described in (B)(ii).

[0076] When Second Polysiloxane (B)(ii) is present, the functional group Y of Polyolefin (B)(iii) may also be reactable with the silicon-bonded functional group X of (B)(ii). For example, aminoalkyl functional groups may be reactable with carboxyl functional groups, epoxide groups and anhydride functional groups.

[0077] The functional groups Y of Polyolefin (B)(iii) may be selected based on the silicon-bonded functional group X of Second Polysiloxane (B)(ii). The functional groups X of Second Polysiloxane (B)(ii) and the functional groups Y of Polyolefin (B)(iii) may be the same functionalgroups or different functional groups, such that the functional groups Y are reactable with one of High-Melting-Temperature Thermoplastic Polymer (B)(i) comprising a polyamide and Second Polysiloxane (B)(ii) or both of High-Melting-Temperature Thermoplastic Polymer (B)(i) comprising a polyamide and Second Polysiloxane (B)(ii).

[0078] Polyolefin (B)(iii) may be selected from polyethylenes, polypropylenes, poly-(C4-Ci2)a-olefins, and copolymers thereof. Poly-(C4-Ci2)a-olefins refers to polymers made from one or more linear a-olefin monomers with carbon chain lengths ranging from C4 (1 -butene) to C12 (1 -dodecene).

[0079] Polyolefin (B)(iii) may have a melt flow index value of 0.1 g / 10 min or more, 0.5 g / 10 min or more, 1 g / 10 min or more, 2 g / 10 min or more, 5 g / 10 min or more, 10 g / 10 min or more, 15 g / 10 min or more, 20 g / 10 min or more, or 25 g / 10 min or more, while at the same time 30 g / 10 min or less, 25 g / 10 min or less, 20 g / 10 min or less, 15 g / 10 min or less, 10 g / 10 min or less, 5 g / 10 min or less, 2 g / 10 min or less, or 1 g / 10 min or less, as determined according to ASTM-D1238. Polyolefin (B)(iii) may have a density value of 0.86 grams per cubic centimeter (g / cm3) or more, 0.88 g / cm3or more, 0.90 g / cm3or more, 0.92 g / cm3or more, or 0.94 g / cm3or more, while at the same time 0.97 g / cm' or less, 0.94 g / cm or less, 0.92 g / cm or less, 0.90 g / cm or less, or 0.88 g / cm3or less, as determined according to ASTM D792.

[0080] Polyolefin (B)(iii) may be present in an amount in a range of 0 to 30 wt.%, and can be 0 wt.% or more, 2.5 wt.% or more, 5 wt.% or more, 10 wt.% or more, 15 wt.% or more, 20 wt.% or more, or 25 wt.% or more, while at the same time 30 wt.% or less, 25 wt.% or less, 20 wt.% or less, 15 wt.% or less, 10 wt.% or less, or 5 wt.% or less, with wt.% values being relative to the weight of the discontinuous phase. Preferably, Polyolefin (B)(iii) is present in an amount in a range of 0 wt.% to 20 wt.%, 2.5 wt.% to 20 wt.%, 5 wt.% to 20 wt.%, 2.5 wt.% to 15 wt.%, or 5 wt.% to 15 wt.%.

[0081] Method for Preparing the Silicone-Thermoplastic Composition

[0082] The method for preparing the silicone-thermoplastic composition of the present invention comprises the following steps:(a) mixing First Polysiloxane (A)(i) and High-Melting-Temperature Thermoplastic Polymer (B)(i) at an elevated temperature greater than the melting temperature (Tm) of the High- Melting-Temperature Thermoplastic Polymer (B)(i), optionally in the presence of Fillers (A)(ii), Second Polysiloxane (B)(ii), Polyolefin (B)(iii), or combinations thereof, to give a mixture; and(b) reducing the elevated temperature of the mixture to a reduced temperature less than the melting temperature of the High-Melting-Temperature Thermoplastic Polymer (B)(i) and thereby producing the silicone -thermoplastic composition.

[0083] First Polysiloxane (A)(i) and the optional Fillers ( A)(ii) may be provided together as a First Polysiloxane Blend. For example, the First Polysiloxane Blend may be commercially available silicone high-consistency rubber (HCR) or a liquid silicone rubber (LSR). HCR is a type of silicone elastomer containing one or more polysiloxane gums as the base polymer. LSR is a silicone elastomer containing one or more flowable polysiloxane as the base polymer. Commercial HCR and LSR compositions generally comprise fillers.

[0084] When First Polysiloxane (A)(i) is a polysiloxane gum, the First Polysiloxane Blend has a William’s plasticity value in a range of 100 mm / 100 to 400 mm / 100, and can be 100 mm / 100 or more, 120 mm / 100 or more, 140 mm / 100 or more, 160 mm / 100 or more, 180 mm / 100 or more, 200 mm / 100 or more, 220 mm / 100 or more, 240 mm / 100 or more, 260 mm / 100 or more, 280 mm / 100 or more, 300 mm / 100 or more, 320 mm / 100 or more, 340 mm / 100 or more, 360 mm / 100 or more, 380 mm / 100 or more, while at the same time can be 400 mm / 100 or less, 380 mm / 100 or less, 360 mm / 100 or less, 340 mm / 100 or less, 320 mm / 100 or less, 300 mm / 100 or less, 280 mm / 100 or less, 260 mm / 100 or less, 240 mm / 100 or less, 220 mm / 100 or less, 200 mm / 100 or less, 180 mm / 100 or less, 160 mm / 100 or less, 140 mm / 100 or less, or 120 mm / 100 or less, as determined by ASTM D926.

[0085] When First Polysiloxane (A)(i) is a in a liquid form and flowable at 25 °C, the First Polysiloxane Blend has a viscosity in a range of 50,000 to 1,000,000 mPa-s, and can be 50,000 mPa-s or more, 75,000 mPa-s or more, 100,000 mPa-s or more, 125,000 mPa-s or more, 150,000 mPa-s ormore, 175,000 mPa-s or more, 200,000 mPa-s or more, 300,000 mPa-s or more, 400,000 mPa- s or more, 500,000 mPa- s or more, 600,000 mPa- s or more, 700,000 mPa- s or more, 800,000 mPa-s or more, 900,000 mPa-s or more, while at the same time can be 1,000,000 mPa-s or less, 900,000 mPa-s or less, 800.000 mPa-s or less, 700,000 mPa-s or less, 600,000 mPa-s or less, 500,000 mPa-s or less, 400,000 mPa-s or less, 300,000 mPa-s or less, 200,000 mPa-s or less, 175,000 mPa-s or less, 150,000 mPa-s or less, 125,000 mPa-s or less, 100,000 mPa-s or less, 75,000 mPa-s or less, as determined according to ASTM-D2196 at 25 °C.

[0086] The elevated temperature can be a value in a range from 100 to 400 °C, such as a value of 100 °C or higher, 125 °C or higher, 150 °C or higher, 175 °C or higher. 200 °C or higher, 225 °C or higher, 250 °C or higher, 275 °C or higher, 300 °C or higher, 325 °C or higher, 350 °C or higher, or 375 °C or higher, while at the same time a value of 400 °C or lower, 375 °C or lower, 350 °C or lower, 325 °C or lower, 300 °C or lower, 275 °C or lower, 250 °C or lower, 225 °C or lower, 200 °C or lower, 175 °C or lower, 150 °C or lower.

[0087] The reduced temperature can be a value equal to or less than 140 °C, such as a value of 20 °C or higher, 40 °C or higher, 60 °C or higher, 80 °C or higher, 100 °C or higher, 120 °C or higher, while at the same time can be 140 °C or less, 120°C or less, 100°C or less, 80 °C or less, 60 °C or less, 40 °C or less.

[0088] The silicone-thermoplastic compositions comprise a number average discontinuous phase domain area (mean domain area per discontinuous phase domain) less than 20 square micrometer (gm ), such as less than 15 pm , less than 10 pm , less than 8 pm", less than 6 pm , less than 4 pm2, or less than 2 pm2, as determined via electron microscopy (e.g. via Scanning Electron Microscope (SEM)). The number average discontinuous phase domain area is greater than 0 pm pm2.

[0089] Optionally, the method of preparing the silicone-thermoplastic compositions may further comprise a step of heating First Polysiloxane (A)(i) to an elevated temperature greater than a melting temperature of High-Melting-Temperature Thermoplastic Polymer (B)(i) prior to step (a).

[0090] Optionally, the method of preparing the silicone-thermoplastic compositions may further comprise a step of incorporating Second Polysiloxane (B)(ii) and / or Polyolefin (B)(iii), sequentially or concurrently, after mixing First Polysiloxane (A)(i) and High-Melting-Temperature Thermoplastic Polymer (B)(i) at an elevated temperature greater than a melting transition temperature of High-Melting-Temperature Thermoplastic Polymer (B)(i), to give a mixture. For example, Polyolefin (B)(iii) may be incorporated first before incorporating Second Polysiloxane (B)(iii).

[0091] Optionally, the method of preparing the silicone-thermoplastic compositions may further comprise a step of combining a curing agent (A)(iii) and the mixture after step (b) to give the silicone-thermoplastic composition.

[0092] Optionally, the method of preparing the silicone-thermoplastic compositions may further comprise a step of incorporating a crosslinking agent (A)(iv), an inhibitor agent (A)(v), or both to the silicone-thermoplastic composition after the step of combining the curing agent ( A)(iii) and the mixture.

[0093] The silicone-thermoplastic compositions described and disclosed herein, when the curing agent (A)(iii) is present, can be cured at a curing temperature in a range of 100 °C to 250°C, and can be 100 °C or higher, 125 °C or higher, 150 °C or higher, 175 °C or higher, 200 °C or higher, or 225 °C or higher, while at the same time 250 °C or lower, 225 °C or lower, 200 °C or lower, 175 °C or lower, 150 °C or lower, or 125 °C or lower. Thus, the method of preparing the siliconethermoplastic compositions may further comprise a step of curing the silicone -thermoplastic composition at a temperature from 100 °C to 250°C to produce a cured product of the silicone-thermoplastic composition. Additionally, the curing temperature may be lower than the melting temperature of High-Melting Temperature Thermoplastic Polymer (B)(i).EXAMPLES

[0094] The following examples are presented to illustrate compositions and methods of this invention.

[0095] Materials

[0096] Table 1. Components utilized in the Examples and their detailed descriptions.>>Rilsamid™ is a trademark owned by Arkema France. Eastar™ is a trademark owned by Eastman Chemical Company. Ultramid™ is a trademark owned by BASF SE. Crastin™ is a trademark owned by DuPont Polymers, Inc. DURACON™ is a trademark owned by Polyplastics Co., Ltd. DOWSIL™ and FUSABOND™ are trademarks owned by the Dow Chemical Company. XIAMETER™ and SYL-OFF™ are trademarks owned by Dow Silicones Corporation. LUPEROX™ is a trademark owned by Arkema, Inc.

[0097] Synthesis of Maleic Anhydride-Terminated PDMS (C4)

[0098] Maleic anhydride-terminated PDMS was produced via grafting maleic anhydride (5.07 g; available from Sigma-Aldrich) onto vinyl-terminated PDMS (150g; 0.93 wt. % vinyl content; viscosity of 130 mPa- s at 20 °C available under the name available as DMS-V-21 from Gelest) in m-xylene (150g; available from Sigma- Aldrich) via free-radical initiation in the presence of benzyl peroxide (6.23 g; available from Sigma-Aldrich). First, maleic anhydride, vinyl-terminated PDMS, and m-xylene were combined at 60 °C under a nitrogen gas purge to form a reactant mixture. Second, benzyl peroxide initiator was added to the reactant mixture to form a reaction mixture. The reaction mixture was heated at 120 °C for two hours and cooled at room temperature. Solvent (m-xylene) and residual crystalline byproducts of peroxide initiator were stripped off from the reaction mixture. The reaction mixture was again heated at 120 °C for additional one hour to produce the maleic anhydride-terminated PDMS with a non-volatile content of above 99.8 wt. %.

[0099] General Procedure for Preparing Examples 1-22 and Comparative Examples 1-4

[0100] Example silicone-thermoplastic compositions can be prepared by any mixer, such as a Haake mixer or a twin-screw extruder.

[0101] Referring to the materials listed in Table 1, the mixer was preheated to a temperature equal to the melting temperature of a selected High-Melting-Temperature Thermoplastic Polymer. First Polysiloxane and the selected High-Melting-Temperature Thermoplastic Polymer were then combined and mixed in the preheated mixer, allowing the High-Melting-Temperature Thermoplastic Polymer to melt and disperse within the First Polysiloxane to form a mixture. During the mixing, the internal temperature of the mixture was elevated to a temperature higher than the melting temperature of the selected High-Melting-Temperature Thermoplastic Polymer due to additional heat from shear mixing. Optionally, a Second Polysiloxane and / or a Polyolefin were incorporated into the mixture. The mixture was then removed from the mixer and cooled to a temperature below the melting temperature of Thermoplastic Polymer to form a siliconethermoplastic composition.

[0102] To cure the silicone-thermoplastic composition, the silicone-thermoplastic composition were combined with a Curing Agent and compounded on a 2-roll mill to form a curable siliconethermoplastic composition. Subsequently, the curable silicone -thermoplastic composition was sheeted and placed in a 25.4 cm x25.4 cm x 2 mm plaque mold to form a plaque. The plaque is cold pressed for 30 seconds under 30 tons of pressure and then hot-pressed for 10 minutes at 175 °C (for Examples using Curing Agent (El)) or 120 °C (for Examples using Curing Agent (E2)) to cure the plaque. The cured plaque is then demolded and die-cut into samples for mechanical testing as described below.

[0103] Compositions of silicone-thermoplastic compositions are shown in Tables 2-5. Weight percent values of individual components are relative to the weight of the silicone -thermoplastic compositions.

[0104] Table 2: Compositions of Examples 1-4 and Comparative Examples 1-2

[0105] Table 3: Compositions of Examples 5-11

[0106] Table 4: Compositions of Cured Examples 12-19 and Comparative Example 3

[0107] Table 5: Compositions of cured Examples 20-22 and Comparative Example 4

[0108] General Procedure for Preparing Examples 23-25 and Comparative Example 5

[0109] Examples 23-25 and Comparative Example 5 were curable silicone-thermoplastic compositions containing Part A and Part B formulations.

[0110] Silicone-Thermoplastic Composition Masterbatch. A Haake mixer was preheated to a temperature equal to the melting temperature of High-Melting-Temperature Thermoplastic Polymer (B6). First Polysiloxane (A3) and High-Melting-Temperature Thermoplastic Polymer(B6) were combined and mixed in the preheated Haake mixer allowing High-Melting-Temperature Thermoplastic Polymer (B6) to melt and disperse within First Polysiloxane (A3) to form a mixture. Polyolefin (D2) and subsequently Second Polysiloxane (C3) were incorporated into the mixture. The mixture was then removed from the mixer and cooled to a temperature below the melting temperature of the High-Melting-Temperature Thermoplastic Polymer (B6) to form a silicone-thermoplastic composition masterbatch used in the Part A formulation. Example siliconethermoplastic composition masterbatches are shown in Table 6A.

[0111] Part A. Part A Formulation contained the silicone-thermoplastic composition masterbatch, another First Polysiloxane (A5), and a Curing Agent (E3).

[0112] PartB. Part B formulation contains First Polysiloxane (A5), an Inhibitor Agent (IA), and a Crosslinking Agent (XA).

[0113] Curable Silicone-Thermoplastic Compositions. Part A and Part B formulations were combined in approximately a 1:1 weight ratio to give the curable silicone-thermoplastic composition. Examples of the curable silicone-thermoplastic compositions are shown in Table 6B.

[0114] The curable silicone-thermoplastic composition was then transferred to a 25.4 cm x 25.4 cm x 1.9 mm press-mold slab, hot-pressed for 10 minutes at 150 °C, and cured into a slab. The cured slab was demolded and die-cut into samples for mechanical testing.

[0115] Table 6A: Compositions of Silicone-Thermoplastic Composition Masterbatches Examples 23-25 and Comparative Example 5

[0116] Table 6B: Compositions of Cured Examples 23-25 and Comparative Example 5

[0117] Dispersion of Discontinuous Phase

[0118] The dispersion of the High-Melting-Temperature Thermoplastic Polymer (B)(i) within the First Polysiloxane (A)(i) was examined using scanning electron microscopy (SEM).

[0119] Example 20 contained neither a Second Polysiloxane nor a Polyolefin. SEM imaging was used to show that the discontinuous phase domains were present in Example 20, with a mean domain area per discontinuous phase domain of 4.38 square micrometer (pm“) with a variance of 124.05 pm2, when neither a Second Polysiloxane nor a Polyolefin was included.

[0120] Examples 21 and 22 both contained a maleic anhydride -grafted high-density polyethylene. SEM image showed that discontinuous phase domains (Polyamide 12) were encased by the maleic anhydride-grafted high-density polyethylene, and the lamellar structure of HDPE at the domain surface. Notably, the mean domain area and the variance in domain size were reduced. For Example 21, the mean domain area per discontinuous phase domain were 2.18 pm“, with a variance of 19.14 pm2. For Example 22, the mean domain area per discontinuous phase domain were 1.59 pm , with a variance of 1.78 pm .

[0121] Mechanical Properties

[0122] Tables 7-10 list the mechanical properties of examples and comparative examples. For mechanical properties listed in Tables 7-11, Shore A hardness of cured products was measured according to ASTM D2240; tensile strength, elongation, and modulus were measured usingmethods described in ASTM D412, Die C; and tear strengths were measured according to ASTM D624, Die B.

[0123] Table 7: Mechanical Properties of Examples 1-4 and Comparative Examples 1-2

[0124] Table 8: Mechanical Properties of Examples 5-11

[0125] Table 9: Mechanical Properties of Examples 12-19 and Comparative Example 3

[0126] Table 10: Mechanical Properties of Examples 20-25 and Comparative Examples 4-5

[0127] Polyamide-containing examples (Exl-Ex3, Ex7-Exl2, and Ex20-Ex25) demonstrated that the inclusion of nylons did not significantly affect the elastomeric properties of the cured thermoplastic-silicone compositions when compared to the comparative examples (CE l, CEx2, CEx4, and CEx5), which were cured silicone formulations without thermoplastic polymers. Surprisingly, in several polyamide-containing examples even exhibited improved elastomeric properties relative to the comparative examples. Specifically, the tear strengths polyamide-containing examples were generally improved (over 20%) compared to the comparative examples. Ex 1-3, Ex7-ll, and Ex22-25 exhibited comparable or greater (over 20%) elongation at break relative to the comparative examples. Most polyamide-containing examples exhibited 100% modulus comparable to the comparative examples or within the margin of measurement error of 10-15%.

[0128] Polyester-containing examples (Ex4-6 and Exl7-19) demonstrated significantly improved 100% modulus (over 20% to about 4000%) relative to the comparative example (CEx3). Ex4-Ex6 also showed improved tear strength compared to the comparative example.

[0129] Polyoxymethylene-containing examples (Exl3-Exl6) demonstrated comparable or improved 100% modulus (over 20% to about 2900%) relative to the comparative example (CEx3). The inclusion of polyoxymethylene did not adversely affect elongation at break, as Exl3-Exl6 maintained the same or improved elongation at break values.

[0130] The present invention provides a silicone-thermoplastic composition comprising discrete domains of high-melt-temperature thermoplastic polymers dispersed within a continuous polysiloxane phase, along with a method for preparing such compositions. These siliconethermoplastic compositions retain elastomeric properties of polysiloxane and, in certain cases, deliver higher mechanical performance to that of the base polysiloxane.

Claims

1. CLAIMSWhat is claimed is:

1. A silicone-thermoplastic composition comprising:(A) a continuous phase comprising:(i) a first polysiloxane, wherein the first polysiloxane has a plasticity number value in a range of 30 to 250 mm / 100 as determined by ASTM D926 at 25 °C or wherein the first polysiloxane has a viscosity value in a range of 50 to 100,000 mPa-s as determined according to ASTM-D2196 at 25 °C; and (ii) optionally, fillers; and(B) a discontinuous phase dispersed within the continuous phase, wherein the discontinuous phase comprises:(i) a thermoplastic polymer comprising a high-melting-temperature thermoplastic polymer selected from polyesters, polyoxymethylenes, a polyamides, and any combination thereof: and(ii) optionally, a second polysiloxane comprising an average of at least one silicon- bonded functional group X per molecule, where each of the silicon-bonded functional group X is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, carbinol functional groups, and combinations thereof;wherein, when the high-melting-temperature thermoplastic polymer (B)(i) comprises a polyamide, the discontinuous phase (B) optionally comprises:(iii) a polyolefin comprising an average of at least one functional group Y per molecule, wherein each of the functional group Y is independently selected from aminoalkyl functional groups, acryloxy functional groups, hydroxyl groups, anhydride functional groups, hydrogen atom, olefinically-unsaturated groups, epoxide functional groups, carboxyl functional groups, amide functional groups, halogen atoms, and combinations thereof.

2. The silicone-thermoplastic composition of claim 1, wherein the first polysiloxane (A)(i) comprises two or more functional groups selected from alkenyl groups and alkynyl groups.

3. The silicone-thermoplastic composition of claim 1 or claim 2, wherein:the first polysiloxane (A)(i) is present in an amount ranging from 35 to 99.5 weight percent, relative to the weight of the continuous phase (A); andthe fillers (A)(ii) are present in an amount ranging from 0 to 60 weight percent, relative to the weight of the continuous phase (A).

4. The silicone-thermoplastic composition of any one of claims 1 to 3, wherein the high-melting- temperature thermoplastic polymer (B)(i) comprises a polyamide.

5. The silicone-thermoplastic composition of any one of claims 1 to 4, wherein each of the silicone-bonded functional group X of the second polysiloxane (B)(ii) is independently selected from aminoalkyl functional groups, anhydride functional groups, and epoxide functional groups.

6. The silicone-thermoplastic composition of any one of claims 1 to 5, wherein the second polysiloxane (B)(ii) is a linear polysiloxane and has a viscosity ranging from 50 to 10,000 mPa-s at 25 °C, determined according to ASTM-D2196.

7. The silicone-thermoplastic composition of any one of claims 1 to 6, wherein the polyolefin (B)(iii) is selected from polyethylenes, polypropylenes, poly-(C4-Ci2)a-olefins, and copolymers thereof; and wherein the polyolefin (B)(iii) has a melt flow index value from 0.1 g / 10 min to 30 g / 10 min, measured according to ASTM-D1238; and a density value of 0.86 to 0.97 g / cm3, measured according to ASTM D792.

8. The silicone-thermoplastic composition of any one of claims 1 to 7, whereinthe high-melting-temperature thermoplastic polymer (B)(i) is present in an amount ranging from 40 to 100 weight percent, relative to the weight of the discontinuous phase (B); the second polysiloxane (B)(ii) is present in an amount ranging from 0 to 60 weight percent, relative to the weight of the discontinuous phase (B); andthe polyolefin (B)(iii) is present in an amount ranging from 0 to 30 weight percent, relative to the weight of the discontinuous phase (B).

9. The silicone-thermoplastic composition of any one of claims 1 to 8, wherein the continuous phase (A) further comprises any one or any combination of more than one of the following components:(iii) a curing agent;(iv) a crosslinking agent; and(v) an inhibitor agent,wherein:the curing agent (A)(iii) comprises a platinum-group metal based catalyst, an organic peroxide compound, a tin(II) compound, a tin(IV) compound, or a titanium compound: the crosslinking agent (A)(iv) comprises a hydrosiloxane, a hydrosilane, an alkenyl- functionalized silane, an alkenyl-functionalized siloxane, an alkynyl-functionalized silane, an alkynyl-functionalized siloxane, or combinations; andthe inhibitor agent (A)(v) comprises an acetylenic alcohol, an alkenyl-functionalized silane, an alkenyl-functionalized siloxane, an alkynyl-functionalized silane, an alkynyl- functionalized siloxane, a dicarboxylic acid, or combinations thereof.

10. The silicone-thermoplastic composition of any one of claims 1 to 9, wherein, when the curing agent (A)(iii) comprises a platinum-group metal based catalyst, the continuous phase (A) comprises the crosslinking agent (A)(iv).

11. A method of preparing the silicone-thermoplastic composition of any one of claims 1 to 10, comprising the following steps:(a) mixing the first polysiloxane (A)(i) and the high-melting-temperature thermoplastic polymer (B)(i) at an elevated temperature greater than a melting temperature of the high-melting-temperature thermoplastic polymer (B)(i), optionally in the presence of the fillers (A)(ii), the second polysiloxane (B)(ii), the polyolefin (B)(iii), or combinations thereof, to give a mixture; and(b) reducing the elevated temperature of the mixture to a reduced temperature less than the melting temperature of the high-melting-temperature thermoplastic polymer (B)(i) and thereby producing the silicone-thermoplastic composition of any one of claims 1 to 10.

12. The method of preparing the silicone-thermoplastic composition of claim 11, wherein the elevated temperature is from 100 °C to 300 °C and the reduced temperature is less than 80 °C.

13. The method of preparing the silicone-thermoplastic composition of claim 11, further comprising the following steps:combining the silicone-thermoplastic composition with any one or any combination of more than one of the following components:(iii) a curing agent;(iv) a crosslinking agent; and(v) an inhibitor agent,wherein:the curing agent comprises a platinum-group metal based catalyst, an organic peroxide compound, or a condensation catalyst;the crosslinking agent (A)(iv) comprises a hydrosiloxane, a hydrosilane, an alkenyl-functionalized silane, an alkenyl-functionalized siloxane, an alkynyl-functionalized silane, an alkynyl-functionalized siloxane, or combinations: andthe inhibitor agent (A)(v) comprises an acetylenic alcohol, an alkenyl- functionalized silane, an alkenyl-functionalized siloxane, an alkynyl- functionalized silane, an alkynyl-functionalized siloxane, a dicarboxylic acid, or combinations thereof;curing the silicone-thermoplastic composition at a curing temperature from 100 °C to 250°C;and thereby producing a cured product of the silicone-thermoplastic composition.

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