Polyolefin / (meth)acrylic composite polymer composition and method for preparing same

Abstract

A composite polymer composition is provided, comprising: (i) an aqueous polyolefin dispersion comprising a melt-kneaded product of one or more polyolefins, 0.5 to 25 wt. % of one or more dispersion stabilizers, and water; and (ii) an emulsion polymerization product of one or more (meth)acrylic monomers, wherein the one or more polyolefins have a Tg of 50°C or less; the melt-kneaded product (i) comprises polymer particles dispersed in water and having a volume average particle size of 50 to 2000 nm; the one or more dispersion stabilizers comprise a fatty acid or fatty acid salt stabilizer; and the one or more (meth)acrylic monomers are grafted onto the polymer particles to form the composite polymer particles. Methods for making the composition and impact modifiers comprising the composition are also provided.

Description

[Technical Field]

[0001] The present invention relates to a polyolefin / (meth)acrylic composite polymer composition and a method for preparing the same. [Background technology]

[0002] Many widely used polymer resins, such as polycarbonate, exhibit good impact performance characteristics under ambient conditions. However, these characteristics deteriorate significantly below room temperature, leading to undesirable cracking or physical failure of the resin. The use of so-called impact modifier additives helps maintain the desirable impact properties of polymer resins at lower temperatures.

[0003] For specific applications such as impact-resistant polymer resins used in automobiles, electronics, and durable articles, there is a market need to improve polymer resin properties, such as low-temperature impact performance, without adversely affecting the weathering properties of the polymer resin.

[0004] One effective type of impact modifier is colloidally stable polymer particles with a diameter of approximately 50–500 nm, prepared by an emulsion polymerization process. These polymer particles exhibit a core-shell morphology, where the core consists of up to approximately 95% by weight of a (co)polymer with a lower glass transition temperature (Tg), and the shell consists of a (co)polymer with a higher Tg. The presence of the higher Tg shell prevents the lower Tg core of the particles from substantially agglomerating when the particles are dried into a powder, and the powdering of the latex is typically done to allow for further processing of the polymer particles (i.e., for dispersion into a polymer resin). In addition, the higher Tg shell helps to compatibilize the polymer particle core with the desired host polymer resin or matrix material. In the absence of a shell, the effect of the impact modifier is significantly limited.

[0005] Impact modifier compositions prepared with low-Tg poly(butadiene) cores generally produce excellent low-temperature impact performance when these polymer particles are dispersed in various resins. However, the weather resistance of these composites is typically insufficient because olefin-containing groups present in the impact modifier particles incorporated into the polymer resin can crosslink or undergo other reactions, causing degradation and making the composite brittle. For polymer resins containing impact modifier compositions prepared with low-Tg poly(butylacrylate) cores, weather resistance is generally excellent, but low-temperature impact performance is generally average. Consequently, the development of a new class of impact modifiers that simultaneously provide both excellent low-temperature impact performance and desirable weather resistance in the host resin represents a significant advance in the art and fulfills an unaddressed need in this field.

[0006] Therefore, available processes for preparing core-shell impact modifiers in the desired size range of 50–500 nm in diameter were limited to monomers that could be polymerized by emulsion polymerization. It was previously not possible to produce impact modifier particles using other chemicals. For example, olefins and olefin copolymers can act as cores, as these compositions are known to be effective impact modifiers due to their low Tg, elastomer properties, and good weather resistance. However, olefin copolymers alone generally do not disperse well in host resins. Furthermore, there are no existing pathways for producing dispersed core-shell particles (having an olefin copolymer core) that are within the required size range of 50–200 nm in diameter and also contain a compatible phase within a multi-domain structure (e.g., core-shell or composite form).

[0007] Hybrid polyolefin-acrylic (POA) particles containing a low-Tg polyolefin core and a high-Tg PMMA phase are prepared as disclosed by Carter et al., “Design and Fabrication of Polyolefin-Acrylic Hybrid Latex Particles,” ACS Appl. Polym. Mater. 2019, 1,3185-3195. However, these hybrid POA particles exhibit low graft efficiency, which is a measure of the degree to which the acrylic polymer is strongly associated with the polyolefin core. Even with process optimization, the highest graft efficiency observed by Carter et al. was <60%.

[0008] There is a need for composite polyolefin-acrylic compositions with higher graft efficiency. It is also desirable to provide composite polyolefin-acrylic compositions that exhibit good performance characteristics, such as weather resistance and low-temperature impact performance, when used in a host polymer resin or matrix. [Overview of the project]

[0009] The present invention relates to a polyolefin / (meth)acrylic composite polymer composition, an impact modifier containing the composite polymer composition, and a method for preparing the same.

[0010] One aspect of the present invention provides a composite polymer composition comprising (i) an aqueous polyolefin dispersion comprising a melt-kneaded product of one or more polyolefins, 0.5 to 25% by weight of one or more dispersion stabilizers, water, and optionally a neutralizing agent, and (ii) an emulsion polymerization product of one or more (meth)acrylic monomers, wherein one or more polyolefins have a Tg of 50°C or less, the melt-kneaded product (i) comprises polymer particles dispersed in water having a volume-average particle size of 50 nm to 2000 nm, the one or more dispersion stabilizers comprises fatty acids or fatty acid salt stabilizers, and one or more (meth)acrylic monomers are grafted onto the polymer particles to form composite polymer particles.

[0011] Another aspect of the present invention provides an impact modifier composition comprising (i) an aqueous polyolefin dispersion comprising a melt-kneaded product of one or more polyolefins, 0.5 to 25% by weight of one or more dispersion stabilizers, water, and optionally a neutralizing agent, and (ii) a dried polymer composition comprising an emulsion polymerization product of one or more (meth)acrylic monomers, wherein one or more polyolefins have a Tg of 50°C or less, the melt-kneaded product (i) comprises polymer particles dispersed in water having a volume-average particle size of 50 nm to 2000 nm, the one or more dispersion stabilizers comprises fatty acids or fatty acid salt stabilizers, and the one or more (meth)acrylic monomers are grafted onto the polymer particles to form composite polymer particles.

[0012] A further aspect of the present invention provides an impact-improving agent-containing resin, hereinafter referred to as an impact-improving resin, comprising: a matrix polymer resin; an aqueous polyolefin dispersion comprising (i) a melt-kneaded product of one or more polyolefins, 0.5 to 25% by weight of one or more dispersion stabilizers, water, and optionally a neutralizing agent; and an impact-improving agent composition comprising a dried polymer composition comprising an emulsion polymerization product of one or more (meth)acrylic monomers, wherein one or more polyolefins have a Tg of 50°C or less, the melt-kneaded product (i) comprises polymer particles dispersed in water having a volume-average particle size of 50 nm to 2000 nm, the one or more dispersion stabilizers comprises fatty acids or fatty acid salt stabilizers, and the one or more (meth)acrylic monomers are grafted onto the polymer particles to form composite polymer particles.

[0013] Further aspects of the present invention provide a method for producing an impact modifier composition, comprising: melt-kneading one or more polyolefins, one or more dispersion stabilizers, water, and optionally a neutralizing agent, wherein one or more polyolefins have a Tg of 50°C or less, and one or more dispersion stabilizers include a fatty acid or fatty acid salt stabilizer; adding one or more (meth)acrylic monomers to the melt-kneading product under emulsion polymerization conditions to form a composite polymer composition; and isolating composite polymer particles by removing water from the polymer particle dispersion, wherein the isolation method is selected from the group consisting of spray drying, solidification, and freeze-drying. [Modes for carrying out the invention]

[0014] The present invention relates to polyolefin / (meth)acrylic composite polymer compositions prepared with fatty acids or fatty acid salt stabilizers, and to methods for preparing the same.

[0015] The composite polymer composition according to the present invention comprises (i) an aqueous polyolefin dispersion comprising a melt-kneaded product of one or more polyolefins, one or more dispersion stabilizers in an amount of 0.5 to 25% by weight, and water, and (ii) an emulsion polymerization product of one or more (meth)acrylic monomers, wherein one or more polyolefins have a Tg of 50°C or less, the melt-kneaded product (i) comprises polymer particles dispersed in water having a volume-average particle size of 50 nm to 2000 nm, the one or more dispersion stabilizers comprises fatty acids or fatty acid salt stabilizers, and the one or more (meth)acrylic monomers are grafted onto the polymer particles to form composite polymer particles.

[0016] The present invention further provides impact modifier compositions comprising a dried product of a composite polymer composition according to any of the embodiments disclosed herein.

[0017] The present invention also provides an impact-improving resin comprising a matrix polymer resin and an impact-improving agent composition according to any of the embodiments disclosed herein.

[0018] The present invention still relates to melt-kneading one or more polyolefins, one or less or one or more dispersion stabilizers, and water, wherein the one or more polyolefins have a Tg of 50 °C or lower, and the one or more dispersion stabilizers include a fatty acid or a fatty acid salt stabilizer; adding one or more (meth)acrylic monomers under emulsion polymerization conditions to the melt-kneaded product to form a composite polymer composition; and isolating composite polymer particles by removing water from the emulsion, the isolation being selected from the group consisting of spray drying, coagulation, and freeze drying. The present invention further provides a method for forming an impact modifier composition comprising the above steps.

[0019] aqueous polyolefin dispersion polyolefin The aqueous dispersion comprises 5 to 99% by weight of one or more polyolefins, based on the total weight of the solid content of the aqueous dispersion. All individual values and subranges from 5 to 99% by weight are included herein and disclosed herein. For example, the weight percent can be from a lower limit of 5, 8, 10, 15, 20, 25% by weight to an upper limit of 40, 50, 60, 70, 80, 90, 95, or 99% by weight. For example, the aqueous dispersion can comprise 15 to 99, or 15 to 90, or 15 to 80, or 15 to 75, or 30 to 70, or 35 to 65% by weight of one or more polyolefins, based on the total weight of the solid content of the aqueous dispersion. The aqueous dispersion comprises at least one or more polyolefins.

[0020] The polyolefins used in the present invention have a Tg of 50°C or less. When two or more polyolefins are used, preferably each polyolefin has a Tg of 50°C or less. All individual values ​​and partial ranges of 50°C or less are included and disclosed herein. For example, the Tg may be 50°C or less, or alternatively, the Tg may be 40°C or less, or alternatively, the Tg may be 30°C or less, or alternatively, the Tg may be 15°C or less, or alternatively, the Tg may be 0°C or less, or alternatively, the Tg may be -15°C or less. Preferably, the polyolefin has a Tg of -50°C or less.

[0021] Examples of polyolefins typically include homopolymers and copolymers of one or more alpha-olefins such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, and 1-dodecene, represented by polyethylene, polypropylene, poly-1-butene, poly-3-methyl-1-butene, poly-3-methyl-1-pentene, poly-4-methyl-1-pentene, ethylene-propylene copolymer, ethylene-1-butene copolymer, and propylene-1-butene copolymer; copolymers of alpha-olefins with conjugated or non-conjugated dienes (including elastomers), typically represented by ethylene-butadiene copolymer and ethylene-ethylidene norbornene copolymer; and copolymers of two or more alpha-olefins with conjugated or non-conjugated dienes (including elastomers), typically represented by ethylene-propylene-butadiene copolymer, ethylene-propylene-dicyclopentadiene copolymer, ethylene-propylene-1,5-hexadiene copolymer, and ethylene-propylene-ethylidene norbornene copolymer, etc. (including elastomers); ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-vinyl chloride copolymer, ethylene acrylic acid or ethylene-(meth)acrylic acid copolymer, and ethylene-(meth)acrylate copolymer, etc. ethylene-vinyl compound copolymers, but not limited to these. These resins can be used alone or in combination of two or more.

[0022] The polyolefin may include one or more polyolefins selected from the group consisting of, for example, ethylene / alpha-olefin copolymers, propylene / alpha-olefin copolymers, and olefin block copolymers. In particular, the polyolefin may include one or more non-polar polyolefins.

[0023] Polyolefins such as polypropylene, polyethylene, copolymers thereof, and blends thereof, as well as ethylene-propylene-diene polymers, may be used. Exemplary olefin polymers include homogeneous polymers such as those described in U.S. Patent No. 3,645,992, high-density polyethylene (HDPE) such as those described in U.S. Patent No. 4,076,698, heterogeneously branched linear low-density polyethylene (LLDPE), heterogeneously branched ultra-low linear-density polyethylene (ULDPE), uniformly branched linear ethylene / alpha-olefin copolymers, for example, uniformly branched substantially linear ethylene / alpha-olefin polymers that can be prepared by processes disclosed in U.S. Patents No. 5,272,236 and No. 5,278,272, whose disclosures are incorporated herein by reference, and high-pressure free-radical polymerized ethylene polymers and copolymers, such as low-density polyethylene (LDPE) or ethylene vinyl acetate polymers (EVA). Polyolefins can be, for example, ethylene-methyl acrylate (EMA) polymers.

[0024] Preferably, the polyolefin may be an ethylene / alpha-olefin copolymer. The polyethylene-alpha-olefin copolymer comprises ethylene-derived units and one or more alpha-olefin-derived polymer units. Examples of one or more alpha-olefin-derived polymer units include, for example, C2 and C4~C 10 Alpha-olefins, preferably C2, C4, C6, and C 8-Alpha-olefins are one example. Examples of polyethylene / alpha-olefin copolymers include, for example, ethylene-butene, ethylene-hexene, or ethylene-octene copolymers or interpolymers.

[0025] Polyolefins may include propylene / alpha-olefin copolymers. Propylene / alpha-olefin copolymers contain units derived from propylene and polymer units derived from one or more alpha-olefin comonomers. Exemplary comonomers used to produce propylene / alpha-olefin copolymers are C2 and C4-C2. 10 Alpha-olefins, such as C2, C4, C6, and C8 alpha-olefins. Examples of propylene / alpha-olefin copolymers include propylene-ethylene, or propylene-ethylene-butene copolymers or interpolymers. Propylene / alpha-olefin copolymers may be characterized by having a substantially isotactic propylene sequence. A "substantially isotactic propylene sequence" means that the sequence is 13 This means that the isotactic triad (mm), as measured by 13C NMR, is greater than approximately 0.85, in alternative cases greater than approximately 0.90, in yet another alternative case greater than approximately 0.92, and in yet another alternative case greater than approximately 0.93. The isotactic triad is well known in the art and is described, for example, in U.S. Patent No. 5,504,172 and International Publication No. WO00 / 01745, which are, 13 This refers to the isotactic sequence of triad units in copolymer molecular chains, as determined by 13C NMR spectroscopy.

[0026] Polyolefins may have a melt flow rate ranging from 1 to 1500 g / 10 min, as measured according to ASTM D-1238 (190°C / 2.16 kg). All individual values ​​and subranges from 1 to 1500 g / 10 min are included in and disclosed herein. For example, the melt flow rate may be between the lower limits of 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, 5 g / 10 min, 100 g / 10 min, 200 g / 10 min, 500 g / 10 min, 800 g / 10 min, 1000 g / 10 min, 1300 g / 10 min, or 1400 g / 10 min, and the upper limits of 1500 g / 10 min, 1250 g / 10 min, 1000 g / 10 min, 800 g / 10 min, 500 g / 10 min, 100 g / 10 min, 50 g / 10 min, 40 g / 10 min, and 30 g / 10 min. For example, propylene / alpha-olefin copolymers may have melt flow rates in the range of 1 to 1500 g / 10 min, or 1 to 500 g / 10 min, or 500 to 1500 g / 10 min, or 500 to 1250 g / 10 min, or 300 to 1300 g / 10 min, or 5 to 30 g / 10 min.

[0027] Polyolefins are defined as the weight-average molecular weight divided by the number-average molecular weight (M w / M n It may have a molecular weight distribution (MWD) of 3.5 or less, or in an alternative example, 3.0 or less, or in another alternative example, 1.8 to 3.0, as defined by ).

[0028] Such polyolefins are marketed by The Dow Chemical Company under the trade names VERSIFY® Plastomers and Elastomers and ENGAGE® Polyolefin Elastomers, or by ExxonMobil Chemical Company under the trade names VISTAMAXX® and EXACT®.

[0029] Polyolefins can also include olefin block copolymers, for example, ethylene multi-block copolymers such as those described in International Publication No. WO2005 / 090427 and U.S. Patent Application Publication No. US2006 / 0199930 (the descriptions of such olefin block copolymers are incorporated herein by reference to the extent that they describe such olefin block copolymers) can be used as polyolefins. Such olefin block copolymers can be ethylene / α-olefin interpolymers, (a) having an M w / M n of about 1.7 to about 3.5, at least one melting point T m in degrees Celsius, and a density d in grams per cubic centimeter, and the numerical values of T m and d are related by the following relationship: T m > -2002.9 + 4538.5(d) - 2422.2(d) 2 or (b) having an M w / M n of about 1.7 to about 3.5, and characterized by a heat of fusion ΔH in J / g and a delta quantity ΔT in degrees Celsius defined as the temperature difference between the highest DSC peak and the highest CRYSTAF peak, and the numerical values of ΔT and ΔH are related by the following relationships: For ΔH greater than zero and at most 130 J / g, ΔT > -0.1299(ΔH) + 62.81, For ΔH greater than 130 J / g, ΔT ≥ 48 °C, The CRYSTAF peak is determined using at least 5 percent of the cumulative polymer, and if less than 5 percent of the polymer has a distinguishable CRYSTAF peak, the CRYSTAF temperature is 30 °C or (c) characterized by an elastic recovery rate Re in percent at 300 percent strain and 1 cycle measured in a compression molded film of the ethylene / α-olefin interpolymer, and having a density d in grams per cubic centimeter, and when the ethylene / α-olefin interpolymer substantially does not contain a crosslinked phase, the numerical values of Re and d are related by the following relationship: Re > 1481 - 1629(d) is satisfied or (d) When fractionated using TREF, the fraction has a molecular fraction that elutes at 40°C to 130°C, and the fraction is characterized by having a molar comonomer content at least 5 percent higher than a comparable random ethylene interpolymer fraction that elutes at the same temperature, wherein the comparable random ethylene interpolymer has the same comonomers as the ethylene / α-olefin interpolymer and has a melt index, density, and molar comonomer content (based on the entire polymer) of no more than 10 percent of that of the ethylene / α-olefin interpolymer, or (e) Storage modulus at 25°C, G'(25°C), and It has a storage modulus at 100°C and G'(100°C), with the ratio of G'(25°C) to G'(100°C) being in the range of approximately 1:1 to 9:1.

[0030] Such olefin block copolymers, for example, ethylene / α-olefin interpolymers, are also (a) When fractionated using TREF, the fraction may have molecular fractions that elute at 40°C to 130°C, and the fractions may have a block index of at least 0.5 and a maximum of about 1 and a molecular weight distribution greater than about 1.3. w / M n It is characterized by having, or (b) Mean block index greater than zero and maximum of approximately 1.0 and molecular weight distribution greater than approximately 1.3 w / M n It may have.

[0031] Polyolefins may include, for example, one or more polar polyolefins having polar groups as either comonomers or grafted monomers. Exemplary polar polyolefins include, but are not limited to, ethylene-acrylic acid (EAA) and ethylene-methacrylic acid copolymers, for example, those available under the trade names PRIMACOR® from The Dow Chemical Company, NUCREL® from EIDuPont de Nemours, and ESCOR® from ExxonMobil Chemical Company, as well as those described in U.S. Patents 4,599,392, 4,988,781, and 5,938,437, each of which is incorporated herein by reference in whole. Other exemplary base polymers include, but are not limited to, ethylene ethyl acrylate (EEA) copolymers, ethylene methyl methacrylate (EMMA), and ethylene butyl acrylate (EBA).

[0032] The polar polyolefin may be selected from the group consisting of ethylene-acrylic acid (EAA) copolymer, ethylene-methacrylic acid copolymer, and combinations thereof, and the stabilizer may include, for example, a polar polyolefin selected from the group consisting of ethylene-acrylic acid (EAA) copolymer, ethylene-methacrylic acid copolymer, and combinations thereof, provided that the base polymer may have a lower acid value than the stabilizer, as measured, for example, according to ASTMD-974.

[0033] Stabilizer The aqueous dispersion further comprises at least one stabilizer, also referred herein as a dispersant, to facilitate the formation of a stable dispersion. The stabilizer may preferably be an external stabilizer. The aqueous dispersion contains 0.5 to 25% by weight of one or more stabilizers based on the total weight of the solids content of the dispersion. All individual values ​​and subranges of 0.5% to 25% by weight are included and disclosed herein, for example, the weight percentage may be a lower limit of 0.5, 1, 2, 5, 7, 9, 11, 14, 19, or 24% by weight to an upper limit of 4, 6, 8, 10, 15, 20, or 25% by weight. For example, the dispersion may contain 0.5 to 25% by weight, or alternatively 1 to 5% by weight, or alternatively 3 to 10% by weight, or alternatively 2 to 8% by weight, or alternatively 5 to 20% by weight, or alternatively 10 to 20% by weight, based on the total weight of the solids content of the dispersion.

[0034] One or more stabilizers include fatty acid or fatty acid salt stabilizers. As used herein, the term “fatty acid” means a carboxylic acid having a saturated or unsaturated hydrocarbon chain and a terminal carboxyl group. If the fatty acid is unsaturated, it may be any enantiomer. Preferably, the fatty acid or fatty acid salt stabilizer is present in an amount ranging from 1 to 6% by weight, more preferably 1.5 to 5% by weight, based on the total weight of the solid content of the dispersion. If a larger amount of fatty acid or fatty acid salt stabilizer is present, it may become more difficult to graft the (meth)acrylic polymer onto the polyolefin. If a smaller amount of fatty acid or fatty acid salt stabilizer is present, the particle size may become too large and / or the grafting efficiency may decrease.

[0035] The fatty acid or fatty acid salt stabilizer contains 4 to 60 carbon atoms. Preferably, the fatty acid or fatty acid salt stabilizer contains at least 8 carbon atoms, more preferably at least 10 carbon atoms, even more preferably at least 12 carbon atoms, and even more preferably at least 14 carbon atoms. Preferably, the fatty acid or fatty acid salt stabilizer contains up to 40 carbon atoms, more preferably up to 30 carbon atoms, and even more preferably up to 24 carbon atoms.

[0036] Preferably, the fatty acid or fatty acid salt contains 16, 18, or 20 carbon atoms. More preferably, the fatty acid or fatty acid salt contains 18 carbon atoms and may be selected from stearic acid, oleic acid, linoleic acid, and their salts.

[0037] Examples of oleic acid salts that may be used include potassium oleic acid salts (e.g., OPK-181 available from RTD Hallstar), sodium oleic acid salts, or ammonium oleic acid salts.

[0038] It has been surprisingly discovered that the use of fatty acid or fatty acid salt stabilizers significantly increases the grafting efficiency of acrylic polymers onto polyolefin cores. When measured according to the process described below, the grafting efficiency of acrylic shells onto olefin cores in the composite polymer of the present invention is 75% or higher. Preferably, the grafting efficiency of the composite polymer composition is 80% or higher, more preferably at least 85%. The grafting efficiency of the composite polymer composition may exceed 90%. In addition to grafting efficiency, fatty acid or fatty acid salt stabilizers can provide composite polymer particles in polyolefin dispersions having small particle sizes, i.e., particle sizes of 2000 nm or less.

[0039] One or more stabilizers may comprise a mixture of two or more stabilizers. For example, one or more stabilizers may comprise an oleic acid surfactant in addition to a non-fatty acid or fatty acid salt stabilizer.

[0040] The additional stabilizers may be surfactants, polymers, or mixtures thereof. The additional stabilizers may be polar polymers having polar groups as either comonomers or grafted monomers. For example, the additional stabilizers may comprise one or more polar polyolefins having polar groups as either comonomers or grafted monomers. Exemplary polymer stabilizers include, but are not limited to, ethylene-acrylic acid (EAA) and ethylene-methacrylic acid copolymers, for example, those available under the trade names PRIMACOR, marketed by The Dow Chemical Company, NUCREL, marketed by EIDuPont de Nemours, and ESCOR, marketed by ExxonMobil Chemical Company, as well as those described in U.S. Patents 4,599,392, 4,988,781, and 5,938,437, each of which is incorporated herein by reference in whole. Other exemplary polymer stabilizers include, but are not limited to, ethylene ethyl acrylate (EEA) copolymers, ethylene methyl methacrylate (EMMA), and ethylene butyl acrylate (EBA). Other ethylene-carboxylic acid copolymers may also be used. Those skilled in the art will recognize that several other useful polymers may also be used.

[0041] Additional stabilizers that may be used include, but are not limited to, long-chain fatty acids, fatty acid salts, or fatty acid alkyl esters having 12 to 60 carbon atoms. Preferably, the long-chain fatty acids or fatty acid salts may have 12 to 40 carbon atoms.

[0042] Other examples of additional stabilizers that may be useful in the practice of the present invention include, but are not limited to, cationic surfactants, anionic surfactants, or nonionic surfactants. Examples of anionic surfactants include, but are not limited to, sulfonates, carboxylates, and phosphates. Examples of cationic surfactants include, but are not limited to, quaternary amines. Examples of nonionic surfactants include, but are not limited to, block copolymers containing ethylene oxide and silicone surfactants.

[0043] Additional stabilizers may be either external or internal surfactants. External surfactants are surfactants that do not chemically react with the polyolefin during the preparation of the dispersion. Examples of external surfactants useful herein include, but are not limited to, salts of dodecylbenzenesulfonic acid and lauryl sulfonates. Internal surfactants are surfactants that are chemically grafted onto the polyolefin during the preparation of the dispersion. Examples of internal surfactants useful herein include 2,2-dimethylolpropionic acid and its salts. Available from RTD Hallstar: OP-100 (sodium stearate) and OPK-1000 (potassium stearate); available from Baker Petrolite: UNICID350; available from Cognis: DISPONIL FES77-IS and DISPONIL TA-430; available from Rhodia: RHODAPEX CO-436, SOPROPHOR4D384, 3D-33, and 796 / P; RHODACAL BX-78 and LDS-22; RHODAFAC RE-610 and RM-710; and SUPRAGIL MNS / 90; and available from The Dow Chemical Company: TRITON QS-15, TRITON W-30, DOWFAX2A1, DOWFAX3B2, DOWFAX8390, DOWFAX C6L, TRITON X-200, TRITON XN-45S, TRITON H-55, TRITON Various commercially available surfactants, including GR-5M, TRITON BG-10, and TRITON CG-110, may be used.

[0044] One or more stabilizers may include, consist of, or essentially consist of fatty acid or fatty acid salt stabilizers. As used herein, the phrase "essentially consisting of fatty acid or fatty acid salt stabilizers" means that one or more stabilizers include, based on the total weight of the stabilizers, any stabilizer other than fatty acid or fatty acid salt stabilizers in less than 5% by weight.

[0045] One or more stabilizers may include a fatty acid or fatty acid salt stabilizer and at least one additional stabilizer. When the composite polymer composition includes a fatty acid or fatty acid salt stabilizer and an additional stabilizer, the fatty acid or fatty acid salt stabilizer and the additional stabilizer may be present in a weight ratio of 20:1 to 1:20, such as 10:1 to 1:10, 5:1 to 1:5, 3:1 to 1:3, 2:1 to 1:2, or 1:1. Preferably, one or more stabilizers include oleates and lauryl ether sulfates, such as sodium lauryl ether sulfate.

[0046] One or more stabilizers may be optionally partially or completely neutralized with a neutralizing agent. The neutralization of one or more stabilizers may be, for example, 25 to 200 percent on a molar basis, and preferably, 50 to 175 percent on a molar basis. For example, if the stabilizers include oleic acid, a salt of oleic acid, or EAA, the neutralizing agent may be a base such as sodium hydroxide or potassium hydroxide. Other neutralizing agents may include, for example, lithium hydroxide or ammonium hydroxide. In another alternative example, the neutralizing agent may be, for example, a carbonate or bicarbonate. In yet another alternative example, the neutralizing agent may be any amine such as monoethanolamine or 2-amino-2-methyl-1-propanol (AMP). Useful amines in the embodiments disclosed herein include monoethanolamine, diethanolamine, triethanolamine, and TRIS AMINO (each available from Angus), NEUTROL TE (available from BASF), as well as triisopropanolamine, diisopropanolamine, and N,N-dimethylethanolamine (each available from The Dow Chemical Company). Other useful amines include ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, mono-n-propylamine, dimethyl-n-propylamine, N-methanolamine, N-aminoethylethanolamine, N-methyldiethanolamine, monoisopropanolamine, N,N-dimethylpropanolamine, 2-amino-2-methyl-1-propanol, tris(hydroxymethyl)-aminomethane, N,N,N'N'-tetrakis(2-hydroxypropyl)ethylenediamine, and 1,2-diaminopropane. Mixtures of amines or mixtures of amines and surfactants may be used. Those skilled in the art will recognize that the selection of an appropriate neutralizing agent may depend on the specific composition being formulated, and that such selection is within the scope of their knowledge.

[0047] fluid medium The dispersion further comprises a fluid medium. The fluid medium can be any medium, for example, water. The dispersion of the present invention contains 35 to 80 volume percent of the fluid medium based on the total volume of the dispersion. For example, the water content may range from 35 to 75, or in alternative cases 35 to 70, or in alternative cases 45 to 60 volume percent, based on the total volume of the dispersion. The water content of the dispersion can preferably be controlled so that the solids content (polyolefin plus stabilizer) is about 1 to about 74 volume percent. The solids range may be, for example, about 10 to about 70 volume percent, for example, about 20 to about 65 volume percent, or about 25 to about 55 volume percent.

[0048] Additional ingredients The aqueous dispersion may optionally further contain one or more additional components. Examples of additional components include, but are not limited to, crosslinking agents, graft binders, binder compositions, fillers, pigments, cosolvents, dispersants, surfactants, defoamers, preservatives, thickeners, and neutralizing agents.

[0049] Examples of crosslinking agents include vinyl group-containing monomers, such as divinylbenzene; triallyl(iso)cyanurate (TAIC); and triallyl trimellitate; and ethylene glycol dimethacrylate. Examples include (poly)alkylene glycol di(meth)acrylate compounds, as well as mixtures and combinations thereof, including dimethacrylate (EGDMA), diethylene glycol dimethacrylate, 1,6-hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene glycol di(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, and glycerol tri(meth)acrylate.

[0050] Exemplary graft binders include, for example, allyl methacrylate, diallyl maleate, and allyl acryloxypropionate.

[0051] Examples of binder compositions include, but are not limited to, acrylic latex, vinyl acrylic latex, styrene acrylic latex, vinyl acetate ethylene latex, and combinations thereof.

[0052] Examples of pigments include, but are not limited to, titanium dioxide, mica, calcium carbonate, silica, zinc oxide, crushed glass, aluminum trihydrate, talc, antimony trioxide, fly ash, and clay.

[0053] Examples of cosolvents include, but are not limited to, glycols, glycol ethers, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, alcohols, mineral spirits, and benzoic acid esters.

[0054] Examples of exemplary dispersions include, but are not limited to, amino alcohols and polycarboxylates.

[0055] Examples of preservatives include, but are not limited to, biocides, fungicides, antifungal agents, algicides, and combinations thereof.

[0056] Examples of thickeners include, but are not limited to, cellulosic thickeners such as hydroxyethylcellulose, hydrophobically modified alkali-soluble emulsions (HASE (hydrophobically modified alkali-soluble emulsion) thickeners such as UCAR POLYPHOBE TR-116), and hydrophobically modified ethoxylated urethane thickeners (HEUR).

[0057] Examples of neutralizing agents include, but are not limited to, hydroxides, amines, ammonia, and carbonates.

[0058] Formation of aqueous dispersion Aqueous dispersions can be formed by any number of methods recognized by those skilled in the art. For example, one or more polyolefins, optionally one or more additives, and optionally one or more stabilizers are melt-kneaded in an extruder with water and a neutralizing agent, such as ammonia, potassium hydroxide, or a combination of the two, to form a dispersion. In another example, one or more polyolefins and one or more additives are compounded, and the polyolefin / subparticle compound is then melt-kneaded in an extruder in the presence of an optionally selected stabilizer, water, and one or more neutralizing agents, thereby forming a dispersion. The dispersion is first diluted to contain about 1 to about 3% by weight of water, and then further diluted to contain more than about 25% by weight of water.

[0059] Any melt-mixing means known in the art can be used. For example, a mixer, a BANBURY® mixer, a single-screw extruder, or a multi-screw extruder, such as a twin-screw extruder, may be used. The process for producing the dispersion according to the present invention is not particularly limited. For example, an extruder such as a twin-screw extruder is connected to a back pressure regulator, a melt pump, or a gear pump. A base reservoir and an initial water reservoir may also be provided, each including a pump. Desired amounts of base and initial water are supplied from the base reservoir and initial water reservoir, respectively. Any suitable pump may be used, for example, a pump that provides a flow rate of about 150 cc / min at a pressure of 240 bar may be used to supply base and initial water to the extruder at a flow rate of 300 cc / min at 200 bar or 600 cc / min at 133 bar. The base and initial water may be preheated in a preheater.

[0060] One or more polyolefins in the form of pellets, powders, or flakes are fed from a feeder to the inlet of the extruder, where the resin is melted or compounded. One or more additives may be fed to the extruder via the feeder simultaneously with the one or more polyolefins, or, in an alternative example, one or more additives may be compounded with the one or more polyolefins and then fed to the extruder via the feeder. In an alternative example, one or more additional additives may be further metered via the inlet before the emulsification zone and added to the molten compound containing the one or more polyolefins and optionally one or more additives. Dispersants may be added through the resin and together with the one or more polyolefins, in another example, the dispersant is supplied separately to the twin-screw extruder. The molten resin is then delivered from the mixing and conveying zone of the extruder to the emulsification zone, where initial amounts of water and base from water and base reservoirs are added via the inlet. Additional dispersants may be added to the water stream. Dispersants may be added exclusively to the water stream. Further dilution water may be added from a water reservoir through the water inlet to either the dilution and / or cooling zone of the extruder. Typically, the dispersion is diluted to approximately 40% by weight of solids in the cooling zone. Furthermore, the dilution mixture may be diluted any number of times until the desired dilution level is achieved. Alternatively, water is added to the resin molten flow after the molten material has exited the extruder, rather than being added to the extruder itself. In this way, vapor pressure buildup within the extruder is eliminated, and the dispersion is formed in a secondary mixing device such as a dynamic-stator mixer.

[0061] Preferably, the pH of the aqueous dispersion is at least 9.

[0062] The melt-kneaded product comprises polymer particles dispersed in water, having a volume-average particle size of 50 nm to 2000 nm. All values ​​and partial ranges of 50 nm to 2000 nm are included and disclosed herein, and for example, particle sizes may range from a lower limit of 150, 350, 550, 750, 950, 1150, 1350, 1550, 1750, or 1950 nm to an upper limit of 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, or 2000 nm. Preferably, the polymer particles have a volume-average particle size of 50 nm or more and 1000 nm or less, more preferably 100 nm or more and 800 nm or less, and even more preferably 150 nm or more and 600 nm or less.

[0063] (meth)acrylic monomer As used herein, the term "(meth)acrylic" means acrylic or methacrylic.

[0064] Examples of (meth)acrylic monomers used herein include C1-C8 (meth)acrylates such as butyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, propyl acrylate, methyl acrylate, hexyl acrylate, butyl methacrylate, methyl methacrylate, ethylhexyl methacrylate, stearyl acrylate, benzyl acrylate, cyclohexyl methacrylate, isobornyl methacrylate, tetrahydrofurfuryl methacrylate, cyclopentyl methacrylate, trifluoroethyl methacrylate, hydroxyethyl methacrylate, and dicyclopentadienyl methacrylate, as well as blends thereof, and combinations thereof.

[0065] (Meth)acrylic monomers may be functionalized, unfunctionalized, or a combination thereof.

[0066] Examples of functionalized (meth)acrylic monomers include, but are not limited to, acrylic acid, methacrylic acid, glycidyl methacrylate, allyl methacrylate, hydroxyethyl methacrylate, and acrylamide.

[0067] Emulsion polymerization Emulsion polymerization conditions are well known in the art. The emulsion polymerization process typically utilizes one or more surfactants. Optionally, exemplary surfactants include, for example, sodium dodecylbenzenesulfonate or sodium lauryl ether sulfate.

[0068] One or more crosslinking agents and / or graft binders may be optionally added to the emulsion polymerization. Examples of crosslinking agents include, for example, vinyl group-containing monomers including divinylbenzene; triallyl(iso)cyanurate (TAIC) and triallyl trimellitate; (poly)alkylene glycol di(meth)acrylate compounds including ethylene glycol dimethacrylate (EGDMA), diethylene glycol dimethacrylate, 1,6-hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene glycol di(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, and glycerol tri(meth)acrylate, as well as mixtures and combinations thereof.

[0069] Exemplary graft binders include, for example, allyl methacrylate, diallyl maleate, and allyl acryloxypropionate.

[0070] The present invention also provides composite polymer compositions, impact modifiers, impact modifier resins, and methods for producing impact modifiers, according to any of the embodiments disclosed herein, except that one or more polyolefins are selected from the group consisting of ethylene homopolymers, ethylene / alpha-olefin copolymers, ethylene / alpha-olefin multiblock interpolymers, propylene homopolymers, propylene / alpha-olefin copolymers, and propylene / alpha-olefin multiblock interpolymers.

[0071] The present invention provides, alternatively, a composite polymer composition, an impact modifier, an impact modifier resin, and a method for producing an impact modifier, according to any of the embodiments disclosed herein, except that one or more (meth)acrylic monomers are selected from the group consisting of functionalized and unfunctionalized (meth)acrylic monomers.

[0072] The present invention also provides, except for one or more vinyl monomers selected from the group consisting of (meth)acrylates, alkyl / aryl (meth)acrylates, functionalized alkyl (meth)acrylates, functionalized and unfunctionalized styrenes, acrylonitriles, butadienes, chloroprene, vinyl chlorides, vinyl acetates, and combinations thereof, one or more of these, as described in any of the embodiments disclosed herein, to produce core / shell polymer compositions, impact modifiers, impact modifier resins, and methods for producing impact modifiers.

[0073] The present invention further provides composite polymer compositions, impact modifiers, impact modifier resins, and methods for producing impact modifiers, according to any of the embodiments disclosed herein, except that emulsion polymerization is carried out in the presence of one or more crosslinking agents and / or graft binders.

[0074] The present invention also provides impact-improving resins according to any of the embodiments disclosed herein, except that the matrix polymer resin is selected from the group consisting of polycarbonate (PC) and PC blends, polyester [e.g., polybutylene terephthalate (PBT) / polyethylene terephthalate (PET) and polylactic acid], polystyrene (PS), styrene copolymers [e.g., acrylonitrile butadiene styrenes (ABS) and styrene-acrylonitrile resin (SAN)], polyvinyl chloride (PVC), polyamide (PA) (e.g., polyamide 6 and polyamide 66), and acetal resins [e.g., polyoxymethylene (POM) copolymer].

[0075] Composite polymer particles The composite polymer particles may exhibit a multi-domain or composite structure comprising a polyolefin phase or component and an acrylic phase or component, the latter of which can serve as a compatibilizing phase in the host polymer resin or matrix. Examples of multi-domain or composite structures according to the present invention include structures comprising a core and at least one shell or phase surrounding the core, such as a multilayer structure, a core / shell structure or a core / shell / shell structure, or a multilobe structure.

[0076] Preferably, the composite structure is a core / shell structure. In the core / shell structure, the core preferably comprises one or more polyolefins and (meth)acrylic monomers polymerized on the polyolefins to form at least a partial shell around the polyolefin core.

[0077] The composite polymer particles may contain 50–95% by weight of olefin-derived units and 5–50% by weight of (meth)acrylic-derived units. All individual values ​​and subranges of 50–95% by weight are included and disclosed herein, for example, the olefin-derived units may be in the upper limit of 55, 60, 65, 70, 75, 80, 85, 90, or 95% by weight to the lower limit of 50, 55, 60, 65, 70, 75, 80, 85, or 90% by weight. For example, the olefin-derived units may be in the range of 50–95% by weight, or alternatively, the olefin-derived units may be in the range of 60–95% by weight, or alternatively, the olefin-derived units may be in the range of 70–90% by weight, or alternatively, the olefin-derived units may be in the range of 85–95% by weight, or alternatively, the olefin-derived units may be in the range of 65–85% by weight. All individual values ​​and subranges of 5 to 50% by weight are included and disclosed herein, for example, the (meth)acrylic unit may be in the upper range of 10, 15, 20, 25, 30, 35, 40, 45, or 50% by weight to the lower range of 5, 10, 15, 20, 25, 30, 35, 40, or 45% by weight. For example, the (meth)acrylic unit may be in the range of 5 to 50% by weight, or alternatively, the (meth)acrylic unit may be in the range of 10 to 50% by weight, or alternatively, the (meth)acrylic unit may be in the range of 5 to 40% by weight, or alternatively, the (meth)acrylic unit may be in the range of 5 to 30% by weight, or alternatively, the (meth)acrylic unit may be in the range of 15 to 35% by weight.

[0078] The (meth)acrylic component may have a Tg of at least 50°C. All individual values ​​and partial ranges of at least 50°C are included and disclosed herein. For example, the Tg of the (meth)acrylic component may be at least 50°C, or alternatively, the Tg of the (meth)acrylic component may be at least 60°C, or alternatively, the Tg of the (meth)acrylic component may be at least 70°C, or alternatively, the Tg of the (meth)acrylic component may be at least 80°C. The (meth)acrylic component may have a Tg of 120°C or less. The meth(acrylic) phase may be partially crosslinked.

[0079] Impact modifiers can be prepared, for example, by isolating or drying composite polymer particles. As used herein, “isolation” or “drying” refers to the process of removing water from an aqueous composition. Isolation and drying methods include, but are not limited to, spray drying, solidification, and freeze-drying. [Examples]

[0080] The following examples illustrate the present invention, but are not intended to limit its scope.

[0081] Aqueous polyolefin dispersion (POD) samples were prepared using a mechanical dispersion process. The preparation of the POD used in Example 2 is provided as a representative example. The POD was prepared using a KWP ZSK25 twin-screw extruder (Krupp Werner & Pfleiderer Corp. (Ramsey, New Jersey)) with a screw diameter of 25 mm, a length-to-diameter ratio (L / D) of 60, and a rotational speed of 450 RPM. ENGAGE® 8137 polyolefin elastomer (60.5 / min) and RETAIN® 3000 polymer modifier (7.6 / min) (both obtained from The Dow Chemical Company (Midland, MI)) were fed into the extruder's feed port via a Schenck MechaTron loss-in-weight feeder and a Schenck volume feeder, respectively. A liquid crosslinking agent, triallyl(iso)cyanurate (TAIC, 1.5 mL / min), was injected into the polymer melting zone using an Isco dual syringe pump (Teledyne Isco, Inc. (Lincoln, NE)). The mixture was melt-blended and emulsified in 2.6 g of water in the presence of an initial aqueous stream containing sodium lauryl ether sulfate (EMPICOL® ESB70, 1.1 g / min, obtained from Huntsman) and sodium oleate solution (Na-oleate, 2.5 g / min). The Na-oleate solution was mixed with a 50 wt% NaOH aqueous solution containing oleic acid (90% purity, Fisher). It was prepared separately by adding (obtained from Chemical). An excess of 175 mol% NaOH was added relative to the number of moles of oleic acid. After melt blending and emulsification, the emulsion phase was passed through the dilution and cooling zone of the extruder, where additional water (100 g / min) was added to form a diluted aqueous dispersion. Both the initial aqueous flow and the dilution water were delivered by an Isco dual syringe pump, and the extruder barrel temperature was set to 140-150°C. After exiting the extruder, the dispersion was allowed to cool to room temperature and filtered through a 200 μm nylon mesh filter bag. A total of 3 L of POD was collected.The volume-average particle size was determined using a Beckman Coulter LS13320 laser light scattering particle analyzer (Fullerton, California). This method assumed an actual fluid refractive index of 1.332, an actual sample refractive index of 1.5, and a hypothetical sample refractive index of 0. Table 1 shows the POD compositions, all values ​​given as weight percentages unless otherwise specified. Note that Example 4 was prepared by cooling and blending two separate PODs prepared by a variation of the above process, thereby using EMPICOL® ESB to prepare one POD and K-oleate to prepare the other POD.

[0082] POA samples were prepared using an emulsion polymerization process. The preparation of the POA used in Example 2 is provided as a representative example. A POD (1500 g) sample as described in Table 1 was diluted to approximately 40% by weight solids with deionized water in a 3 L four-necked round-bottom flask equipped with a condenser, temperature probe, and mechanical stirrer. The flask was placed under nitrogen, the stirring speed was set to 250 RPM, and the temperature of the dispersion was controlled to 65°C with a heated mantle. A solution of EDTA (3.2 mL, 1.0 wt% in water) was added to the reactor, followed by FeSO4. 4·A solution of 7H2O (14.7 mL, 0.15 wt% in water) was added. Separately prepared 70 wt% solutions of tert-butyl hydroperoxide (t-BHP, 2.7 g in 50.7 g of water) and sodium formaldehyde sulfoxylate (SFS, 1.9 g in 50.7 g of water) were added to the reactor over 60 minutes. The contents of the reactor were then maintained at 65°C for 30 minutes. In a separate glass container, a monomer emulsion (ME) containing deionized water (66.5 g), sodium dodecylbenzenesulfonate (1.3 g, 22.0 wt% solution in water), butyl acrylate (BA, 3.2 g), and methyl methacrylate (MM, 155.2 g) was prepared. The mass ratio of POD to monomer was 80:20. Solutions of t-BHP (0.5 g in 15.4 g of water) and SFS (0.3 g in 15.4 g of water) were prepared and loaded into plastic syringes. The supply of ME and redox versus t-BHP / SFS solutions was started simultaneously. ME was supplied to the reactor over 60 minutes, and the redox initiator package was supplied over a total of 90 minutes (i.e., after the ME supply was complete, the co-supply of redox continued for 30 minutes). The reactor was then held at 65°C for 20 minutes and then cooled to room temperature. The resulting sample was filtered through a 100-mesh stainless steel filter.

[0083] To measure the graft efficiency of a given sample (i.e., the degree of association between the POD core and the acrylic phase), solvent extraction was performed as disclosed by Carter et al., Design and Fabrication of Polyolefin-Acrylic Hybrid Latex Particles, ACS Appl. Polym. Mater. 2019, 1, 3185-3195. Briefly, the POA sample was added to tetrahydrofuran (THF) and stirred overnight at room temperature (approximately 1:25 wt:pOA:THF). The sample was then spiked with an equal volume of acetonitrile (ACN), and the liquid phase was isolated by centrifugation. Separately, GPC calibration curves were constructed from the serial dilution and refractive index detector area integral responses of known masses of uncrosslinked PMMA latex. For a given POA sample, the area of ​​the peak in the GPC chromatogram corresponding to the ungrafted acrylic polymer was compared with the calibration curve and subtracted from the known total mass of acrylic in the system to obtain the graft efficiency. The graft efficiencies determined using this method in the examples are shown in Table 1.

[0084] To obtain a dried powdered POA sample, the following general coagulation procedure was used: 7.4 g of CaCl2 and 2.2 g of concentrated HCl dissolved in 1800 g of deionized water. (aq) The solution was added to a 4L glass beaker and heated to 75°C while stirring. Separately, the POA samples listed in Table 1 were diluted with deionized water to a solid content of approximately 30% by weight. A portion of the diluted POA sample (900g) was heated to 70°C while stirring, and then the CaCl2 / HCl in water was added. (aq)The entire mixture was added at once to the preheated solution. The resulting mixture was kept at 75°C with stirring for 5 minutes, and then neutralized to approximately pH 7 using an aqueous phosphate solution (8.3 g monosodium phosphate and 36.7 g disodium phosphate in 855 g of deionized water). The neutralized mixture was then rapidly heated to 90°C and kept at 90°C for 30 minutes, and then cooled to 60°C. At 60°C, the reaction mixture was vacuum filtered through a Buchner funnel and Whatman filter paper. The resulting wet filtration cake was thoroughly washed with deionized water and then dried in a vacuum oven at 60°C for 24 hours to obtain a white powder.

[0085] [Table 1]

[0086] Compounding and injection molding procedure Grafted polyolefin-acrylic core-shell particles were used as impact modifiers in polycarbonate resin (CALIBRE200, available from Covestro). The results were compared to the performance of a commercially available methyl methacrylate-butadiene-styrene (MBS) impact modifier (PARALOID® EXL2690, available from The Dow Chemical Company).

[0087] Prior to compounding, the PC resin sample was dried in an oven at 110°C for 2-4 hours. The PC resin and a predetermined mass of dry impact modifier (3 or 5% by weight of impact modifier based on total mass) were combined and manually mixed, then compounded using a JSW28 co-rotating twin-screw extruder (L / D=40). The resin and impact modifier were supplied to the extruder's feed port via a weight K-Tron feeder and then melt-blended. The extruded sample strand was then cooled in a water trough, passed through an air knife to remove water from the strand surface, and pelletized using a particle size analyzer. The extruder temperature profile was set to 260-270-280-285-290°C (from hopper to die), and compounding was performed at a screw speed of 150 rpm and an output of 10 kg / hour.

[0088] The resulting PC pellets were dried in a low-pressure dryer at 110°C for 4 hours, and then injection molded into a die using the following temperature profile: 280-280-285-290°C (from hopper to die) to obtain dogbone-shaped or rectangular bars for impact testing.

[0089] The following test methods include measuring the melt flow rate (MFR) according to ISO 1133 and the notched Izod impact strength according to ASTM D256. For each method, at least five samples were tested.

[0090] [Table 2]

[0091] [Table 3]

[0092] [Table 4]

[0093] Test method The test method includes the following: Density of ethylene-based polymers measured according to ISO 1183.

[0094] Density of propylene-based polymers measured according to ASTM D792.

[0095] MFR measured according to ISO 1133.

[0096] Notched Izod impact strength measured according to ASTM D256.

[0097] The present invention may be embodied in other forms without departing from its spirit and essential attributes; therefore, the appended claims, rather than the foregoing specification, should be referenced to illustrate the scope of the present invention.

Claims

1. 1. A composite polymer composition comprising: (i) an aqueous polyolefin dispersion comprising a melt-kneaded product of one or more polyolefins, 0.5 to 25 wt. % of one or more dispersion stabilizers, water, and optionally a neutralizing agent; and (ii) comprises the emulsion polymerization product of one or more (meth)acrylic monomers; the one or more polyolefins have a Tg of 50°C or less; The melt-kneaded product (i) contains polymer particles dispersed in the water and having a volume average particle size of 50 nm to 2000 nm, the one or more dispersion stabilizers comprise a fatty acid or fatty acid salt stabilizer; The composite polymer composition, wherein the one or more (meth)acrylic monomers are grafted onto the polymer particles to form composite polymer particles.

2. 10. The composite polymer composition of claim 1, wherein the fatty acid or fatty acid salt stabilizer contains from 8 to 28 carbon atoms.

3. 3. The composite polymer composition of claim 2, wherein the fatty acid or fatty acid salt stabilizer contains from 12 to 24 carbon atoms.

4. 4. The composite polymer composition of claim 3, wherein the fatty acid or fatty acid salt stabilizer contains 16, 18, or 20 carbon atoms.

5. 5. The composite polymer composition of claim 4, wherein the fatty acid or fatty acid salt stabilizer comprises stearic acid, oleic acid, or linoleic acid, or salts thereof.

6. The composite polymer composition of any one of claims 1 to 5, wherein the one or more dispersion stabilizers further comprise a mixture of at least two dispersion stabilizers.

7. The polymer composition of any one of claims 1 to 6, wherein the composite polymer particles have a grafting efficiency of at least 80%.

8. The composite polymer composition of any one of claims 1 to 7, wherein the ratio of polyolefin to poly(meth)acrylic is from 60:40 to 95:

5.

9. 9. The composite polymer composition of any one of claims 1 to 8, wherein the one or more polyolefins are selected from the group consisting of ethylene homopolymers, ethylene / α-olefin copolymers, ethylene / α-olefin multi-block interpolymers, propylene homopolymers, propylene / α-olefin copolymers, and propylene / α-olefin multi-block interpolymers.

10. The composite polymer composition of any one of claims 1 to 9, wherein the one or more (meth)acrylic monomers are selected from the group consisting of functionalized (meth)acrylic monomers.

11. The composite polymer composition of any one of claims 1 to 10, wherein the composite polymer particles have a core / shell or core / partial shell structure.

12. The composite polymer composition of any one of claims 1 to 11, wherein the (meth)acrylic shell is partially crosslinked and has a Tg of 50°C or greater.

13. 1. An impact modifier composition comprising: An impact modifier composition comprising the dried product of the composite polymer composition of any one of claims 1 to 12.

14. An impact-modifying resin, a matrix polymer resin; and the impact modifier composition of claim 10.

15. 1. A method for forming an impact modifier composition, comprising: melt-kneading one or more polyolefins, one or more dispersion stabilizers, water, and optionally a neutralizing agent, wherein the one or more polyolefins have a Tg of 50°C or less, and the one or more dispersion stabilizers comprise a fatty acid or fatty acid salt stabilizer; adding one or more (meth)acrylic monomers to the melt-kneaded product under emulsion polymerization conditions to form a composite polymer composition; isolating the composite polymer particles by removing water from the emulsion, isolating by a method selected from the group consisting of spray drying, coagulation, and freeze drying.