Thermoplastic polymer compositions with improved processability and mechanical properties - Patents.com

Abstract

The present invention relates to a thermoplastic polymer composition. The thermoplastic polymer composition comprises: (a) a copolymer (A) having polymer units derived from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers; and (b) a rubber-modified thermoplastic polymer (E), the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0 wt%, preferably ≧57.0 wt%, based on the total weight of the copolymer. The present invention further relates to a method for preparing such a thermoplastic composition, and to an article formed from such a thermoplastic composition. In addition, the present invention further relates to the use of the thermoplastic composition to improve the processability of the polymer composition suitable for thermoplastic processing, and the mechanical properties of impact and tensile strain.

Description

[Technical field]

[0001] The present invention relates to the field of thermoplastic polymer compositions, such as acrylonitrile butadiene and styrene (ABS) based compositions, which have an excellent balance of processability and mechanical properties. The present invention further relates to methods for preparing such thermoplastic compositions, and to articles prepared from such thermoplastic compositions. Additionally, the present invention relates to the use of the thermoplastic compositions to improve the processability and mechanical properties of polymer compositions suitable for injection molding. [Background technology]

[0002] Thermoplastic polymer compositions, such as those based on acrylonitrile-butadiene-styrene (ABS), are widely used to manufacture products using processing techniques such as injection molding. Industry professionals often require that thermoplastic polymers have excellent flow properties during processing without compromising the impact and / or tensile strain mechanical properties of such polymers. However, for polymers, flow and mechanical properties such as impact strength are often observed to be inversely correlated, such that attempts to improve one property result in a negative impact on the other competing property.

[0003] For example, processing requirements often dictate that thermoplastic compositions used in injection molding should have specific flow properties, especially when manufacturing thin-walled articles with complex design features (e.g., automotive parts). Appropriate flow properties can help improve the processability of the polymer and reduce structural and aesthetic defects caused by polymer sagging during processing. However, it has been observed that in many cases, attempts to improve the flow properties of injection-moldable polymer compositions come at the expense of reduced impact and tensile strain mechanical properties.

[0004] In the past, to address such issues, industry professionals would often physically mix a "high impact" polymer compound (e.g., a high impact ABS grade polymer compound) with a "high flow" polymer compound (e.g., a high flow ABS grade polymer compound) in an attempt to obtain a polymer compound with a desired balance of mechanical and flow properties. However, such an approach involves additional processing steps and requires extensive inventory management, making the overall manufacturing process inefficient. Furthermore, it is often difficult to control the flow uniformity of the resulting compound, resulting in quality control problems for polymer converters.

[0005] On the other hand, impact modifiers such as silicone oils are often used to increase the impact resistance of thermoplastic polymers without affecting the flow properties of the polymer. However, such an approach can increase the production cost as well as the processing complexity, which may make such an approach undesirable in some cases.

[0006] Further alternative approaches are described in US Pat. No. 5,399,433, including blends based on ABS and copolymers of methyl methacrylate, styrene, and acrylonitrile, however, the exemplary data provided in US Pat. No. 5,399,433 suggest that the balance between flow and mechanical properties of such blends could be further improved for certain applications. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] European Patent No. 2053090 Summary of the Invention [Problem to be solved by the invention]

[0008] It is therefore an object of the present invention to provide a thermoplastic polymer composition that exhibits an appropriate balance between flow properties and mechanical properties of impact and tensile strain.It is yet another object of the present invention to develop a thermoplastic polymer composition that exhibits a desired balance between flow properties and mechanical properties of impact and tensile strain even in the absence of impact modifiers such as silicone oils. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Thus, one or more of the objects of the present invention are achieved by a thermoplastic polymer composition comprising: a. ≧50.0wt% and ≦70.0wt%, preferably ≧60.0wt% and ≦69.0wt%, preferably ≧65.0wt% and ≦69.0wt%, based on the total weight of the thermoplastic polymer composition, of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers; b. ≧30.0wt% and ≦50.0wt%, preferably ≧31.0wt% and ≦40.0wt%, preferably ≧31.0wt% and ≦35.0wt% of a rubber-modified thermoplastic polymer (E) based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg, of ≧7.0 g / 10 min and ≦20.0 g / 10 min, preferably ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min.

[0010] Preferably, the thermoplastic polymer composition comprises: a. ≧60.0 wt. % and ≦69.0 wt. % of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers, and (ii) vinyl nitrile monomers, based on the total weight of the thermoplastic polymer composition; b. ≧31.0wt% and ≦40.0wt% of a rubber-modified thermoplastic polymer (E), based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. and a load of 1.2 kg, of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min.

[0011] Preferably, the thermoplastic polymer composition comprises: a. ≧65.0 wt. % and ≦69.0 wt. % of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers, and (ii) vinyl nitrile monomers, based on the total weight of the thermoplastic polymer composition; b. ≧31.0wt% and ≦35.0wt% of a rubber-modified thermoplastic polymer (E), based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. and a load of 1.2 kg, of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min.

[0012] Preferably, the thermoplastic polymer composition comprises: a. ≧65.0 wt. % and ≦69.0 wt. % of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers, and (ii) vinyl nitrile monomers, based on the total weight of the thermoplastic polymer composition; b. ≧31.0wt% and ≦35.0wt% of a rubber-modified thermoplastic polymer (E), based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate of ≧9.0 g / 10 min and ≦11.0 g / 10 min, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg.

[0013] Preferably, the thermoplastic polymer composition comprises ≦0.001 wt.-%, preferably ≦0.0001 wt.-%, preferably zero (0.0) wt.-% of silicone oil, based on the total weight of the thermoplastic polymer composition.

[0014] The inventors have discovered that when a copolymer (A) having a specific melt flow rate is combined with a rubber-modified thermoplastic polymer (E) in a specific ratio, the resulting polymer thus formed has a desired balance between flow properties or processability and mechanical properties. Advantageously, in some embodiments of the present invention, the thermoplastic polymer composition exhibits a suitable balance between flow properties and mechanical properties of impact and tensile strain, even when such thermoplastic polymer composition is substantially free of silicone oil. As a further advantage, in some embodiments of the present invention, the thermoplastic polymer composition avoids the need to use silicone oil to enhance impact properties, thereby avoiding some processing complications and making the polymer production process more efficient and cost-effective.

[0015] Thus, in some embodiments of the present invention, the thermoplastic polymer composition comprises: a. ≧50.0wt% and ≦70.0wt%, preferably ≧60.0wt% and ≦69.0wt%, preferably ≧65.0wt% and ≦69.0wt%, based on the total weight of the thermoplastic polymer composition, of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers; b. ≧30.0wt% and ≦50.0wt%, preferably ≧31.0wt% and ≦40.0wt%, preferably ≧31.0wt% and ≦35.0wt% of a rubber-modified thermoplastic polymer (E) based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate of ≧7.0 g / 10 min and ≦20.0 g / 10 min, preferably ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, measured according to ISO 1133 (2005) at 230° C. and a load of 1.2 kg, and the thermoplastic polymer composition may contain ≦0.001 wt. %, preferably ≦0.0001 wt. %, preferably zero (0.0) wt. % of silicone oil, based on the total weight of the thermoplastic polymer composition.

[0016] Preferably, the thermoplastic polymer composition comprises: a. ≧60.0 wt. % and ≦69.0 wt. % of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers, and (ii) vinyl nitrile monomers, based on the total weight of the thermoplastic polymer composition; b. ≧31.0wt% and ≦40.0wt% of a rubber-modified thermoplastic polymer (E), based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, measured according to ISO 1133 (2005) at 230° C. and a load of 1.2 kg; furthermore, the thermoplastic polymer composition may contain ≦0.0001 wt. %, preferably zero (0.0) wt. %, of a silicone oil, based on the total weight of the thermoplastic polymer composition.

[0017] Preferably, the thermoplastic polymer composition comprises: a. ≧65.0 wt. % and ≦69.0 wt. % of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers, and (ii) vinyl nitrile monomers, based on the total weight of the thermoplastic polymer composition; b. ≧31.0wt% and ≦35.0wt% of a rubber-modified thermoplastic polymer (E), based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg, of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, and further, the thermoplastic polymer composition may contain zero (0.0) wt. % of silicone oil, based on the total weight of the thermoplastic polymer composition.

[0018] Preferably, in some aspects of the present invention, the present invention relates to the use of the thermoplastic polymer composition of the present invention to improve the processability and mechanical properties of polymer compositions suitable for thermoplastic processing, which may include, for example, the processes of extrusion, injection molding, blow molding, and thermoforming.

[0019] Copolymer (A): The thermoplastic polymer composition may contain any suitable amount of copolymer (A), for example, the thermoplastic polymer composition has ≧50.0% and ≦70.0% by weight, preferably ≧60.0% and ≦69.0% by weight, preferably ≧65.0% and ≦69.0% by weight of copolymer (A) based on the total weight of the thermoplastic polymer composition.

[0020] Copolymer (A) may be selected to have suitable flow properties, for example. For example, copolymer (A) may have a melt flow rate of ≧7.0g / 10min and ≦20.0g / 10min, preferably ≧8.0g / 10min and ≦15.0g / 10min, preferably ≧9.0g / 10min and ≦11.0g / 10min, measured according to ISO1133 (2005) at 230°C and 1.2kg load. The inventors have found that if the melt flow rate of copolymer (A) is too high, the overall impact properties of the thermoplastic polymer composition may be adversely affected, while if the melt flow rate of copolymer (A) is too low, the desired flow properties of the thermoplastic polymer are not obtained, affecting the processability of the thermoplastic polymer.

[0021] Copolymer (A) may have a suitable molecular weight.For example, copolymer (A) has an average molecular weight (Mw) of ≧50,000g / mol and ≦100,000g / mol, preferably ≧80,000g / mol and ≦100,000g / mol, preferably ≧85,000g / mol and ≦98,000g / mol, preferably ≧93,000g / mol and ≦97,000g / mol, as measured by gel permeation chromatography according to ASTM D5296-11.For example, the molecular weight measurement is carried out by gel permeation chromatography according to ASTM D5296-11, using polystyrene-based calibration as a solvent in tetrahydrofuran (THF).

[0022] Preferably, the copolymer (A) is a. an average molecular weight (Mw) of ≧50,000 g / mol and ≦100,000 g / mol, preferably ≧80,000 g / mol and ≦100,000 g / mol, preferably ≧85,000 g / mol and ≦98,000 g / mol, preferably ≧93,000 g / mol and ≦97,000 g / mol, as measured by gel permeation chromatography according to ASTM D5296-11; b. ≧20.0% and ≦26.0% by weight, preferably ≧22.0% and ≦26.0% by weight, preferably ≧23.0% and ≦26.0% by weight, of polymer units derived from vinyl nitrile monomers, based on the total weight of the copolymer (A).

[0023] Copolymer (A) may, for example, be composed of polymer units derived from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers.

[0024] The vinyl aromatic monomer may be selected from, for example, styrene, α-methylstyrene, dibromostyrene, vinyltoluene, vinylxylene, butylstyrene, p-hydroxystyrene, methoxystyrene, or any combination thereof. Preferably, the vinyl aromatic monomer may be selected from styrene, α-methylstyrene, or any combination thereof. More preferably, the vinyl aromatic monomer may be styrene.

[0025] The vinyl nitrile monomer may be selected from, for example, acrylonitrile, α-chloroacrylonitrile, methacrylonitrile, ethacrylonitrile, or any combination thereof. Preferably, the vinyl nitrile monomer may be acrylonitrile. Preferably, the copolymer (A) has a suitable amount of polymer units derived from vinyl nitrile monomers. For example, the copolymer (A) has ≧20.0 wt% and ≦26.0 wt%, preferably ≧22.0 wt% and ≦26.0 wt%, preferably ≧23.0 wt% and ≦26.0 wt%, based on the total weight of the copolymer (A). Thus, the copolymer (A) has ≧74.0 wt% and ≦80.0 wt%, preferably ≧74.0 wt% and ≦78.0 wt%, preferably ≧74.0 wt% and ≦77.0 wt%, based on the total weight of the copolymer (A), of polymer units derived from vinyl aromatic monomers.

[0026] In some embodiments of the present invention, the copolymer (A) may be, for example, a terpolymer comprising polymer units derived from (i) a vinyl aromatic monomer, (ii) a vinyl nitrile monomer, and (iii) a (meth)acrylic monomer. The vinyl aromatic monomer and the vinyl nitrile monomer may be selected from the monomers defined herein. The (meth)acrylic monomer may be, for example, selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, and decyl methacrylate. Preferably, the (meth)acrylic monomer may be methyl methacrylate (MMA). Thus, the copolymer (A) may be, for example, a terpolymer comprising polymer units derived from styrene / acrylonitrile / methyl methacrylate, or alpha-methyl-styrene / acrylonitrile / methyl methacrylate.

[0027] Preferably, in some embodiments of the present invention, copolymer (A) is substantially free of polymer units derived from (meth)acrylic monomers. In a preferred embodiment of the present invention, copolymer (A) may contain ≦5.0 wt.%, preferably ≦2.0 wt.%, preferably ≦1.0 wt.%, preferably ≦0.5 wt.% of polymer units derived from (meth)acrylic monomers. Preferably, copolymer (A) contains ≧0.0 wt.% and ≦5.0 wt.%, preferably ≧0.0 wt.% and ≦2.0 wt.%, preferably ≧0.0 wt.% and ≦1.0 wt.%, preferably ≧0.0 wt.% and ≦0.5 wt.% of polymer units derived from (meth)acrylic monomers, based on the total weight of copolymer (A).

[0028] Thus, in some preferred embodiments of the present invention, copolymer (A) may be composed of polymer units derived only from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers. In some preferred embodiments of the present invention, copolymer (A) may comprise a styrene-acrylonitrile copolymer (SAN).

[0029] In some preferred embodiments of the present invention, the copolymer (A) has ≧20.0 wt.% and ≦26.0 wt.%, preferably ≧22.0 wt.% and ≦26.0 wt.%, preferably ≧23.0 wt.% and ≦26.0 wt.%, based on the total weight of the copolymer (A). The styrene-acrylonitrile copolymer (SAN) can be selected to have a melt flow rate of ≧7.0 g / 10 min and ≦20.0 g / 10 min, preferably ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, measured according to ISO 1133 (2005) at 230 ° C and a load of 1.2 kg.

[0030] Rubber modified thermoplastic polymer (E): The thermoplastic polymer composition may contain a suitable amount of the rubber-modified thermoplastic polymer (E). For example, the thermoplastic polymer composition has ≧30.0 wt% and ≦50.0 wt%, preferably ≧31.0 wt% and ≦40.0 wt%, preferably ≧31.0 wt% and ≦35.0 wt% of the rubber-modified thermoplastic polymer (E) based on the total weight of the thermoplastic polymer composition.

[0031] The rubber modified thermoplastic polymer (E) comprises a polymer rubber grafted with a graft thermoplastic copolymer (C). In some embodiments of the present invention, the polymer rubber may be a discontinuous elastomeric phase dispersed throughout a continuous rigid thermoplastic phase comprising the graft thermoplastic copolymer (C), where at least a portion of the rigid thermoplastic phase is grafted to the elastomeric phase. The polymer rubber may, for example, have a suitable particle-based morphology. For example, the polymer rubber may be in the form of rubber particles and may have a broad monomodal particle size distribution. The polymer rubber may, for example, have an average particle size of ≧50 nanometers (nm) and ≦1000 nanometers (nm), preferably ≧200 nanometers (nm) and ≦500 nanometers (nm).

[0032] The polymeric rubber may, for example, comprise polymeric units derived from conjugated dienes and, optionally, polymeric units derived from one or more monomers selected from vinyl aromatic monomers and / or vinyl nitrile monomers. For example, the polymeric rubber may comprise ≧90.0% and ≦100% by weight, preferably ≧95.0% and ≦100% by weight, based on the total weight of the polymeric rubber, of polymeric units derived from conjugated dienes, and may optionally comprise ≧0.0% and ≦10.0% by weight, preferably ≧0.0% and ≦5.0% by weight, based on the total weight of the polymeric rubber, of polymeric units derived from vinyl aromatic monomers and / or vinyl nitrile monomers.

[0033] The rubber-modified thermoplastic polymer (E) is, for example, a. A polymeric rubber, i. ≧90.0wt% and ≦100wt%, preferably ≧95.0wt% and ≦100wt%, based on the total weight of the polymer rubber, of polymer units derived from conjugated dienes, the conjugated dienes being selected from 1,3-butadiene, isoprene, 1,3-heptadiene, methyl-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, or any combination thereof, preferably the conjugated diene being selected from 1,3-butadiene, isoprene, or any combination thereof, more preferably the conjugated diene is 1,3-butadiene; ii. a polymeric rubber comprising ≧0.0 wt.% and ≦10.0 wt.%, preferably ≧0.0 wt.% and ≦5.0 wt.%, based on the total weight of the polymeric rubber, of polymeric units derived from vinyl aromatic monomers and / or vinyl nitrile monomers, the vinyl aromatic monomers being selected from styrene, α-methylstyrene, or any combination thereof, and the vinyl nitrile monomer being acrylonitrile; b. a graft thermoplastic copolymer (C), the graft thermoplastic copolymer (C) being grafted to a polymer rubber, the graft thermoplastic copolymer (C) being i. a vinyl aromatic monomer selected from styrene, α-methylstyrene, dibromostyrene, vinyl toluene, vinyl xylene, butyl styrene, p-hydroxystyrene, methoxystyrene, or any combination thereof, preferably, the vinyl aromatic monomer is styrene; ii. a vinyl nitrile monomer selected from acrylonitrile, methacrylonitrile, ethacrylonitrile, or a combination thereof, preferably, the vinyl nitrile monomer is acrylonitrile; and iii. optionally a (meth)acrylic monomer selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, and decyl methacrylate, preferably the (meth)acrylic monomer is methyl methacrylate (MMA); and a graft thermoplastic copolymer (C) comprising polymer units derived from Furthermore, the rubber-modified thermoplastic polymer (E) has a polymer rubber content of ≧55.0% and ≦75.0% by weight, preferably ≧57.0% and ≦70.0% by weight, preferably ≧60.0% and ≦65.0% by weight, preferably ≧60.0% and ≦63.0% by weight, based on the total weight of the rubber-modified thermoplastic polymer (E). The polymer rubber content may be measured, for example, using Fourier Transform Infrared Micro-Spectroscopy (FT-IR).

[0034] In some embodiments of the present invention, the polymeric rubber may comprise polymeric units derived from only conjugated dienes, such as only 1,3-butadiene to form polybutadiene. Thus, in some embodiments of the present invention, the polymeric rubber is polybutadiene. In some embodiments of the present invention, the polymeric rubber comprises an elastomeric copolymer derived from a conjugated diene and a vinyl aromatic monomer. For example, in some embodiments of the present invention, the polymeric rubber may be an elastomeric copolymer comprising polymeric units derived from 1,3 butadiene and styrene.

[0035] In some other embodiments of the present invention, the polymeric rubber comprises an elastomeric copolymer derived from conjugated diene and vinyl nitrile monomers. For example, in some embodiments of the present invention, the polymeric rubber is an elastomeric copolymer comprising polymeric units derived from 1,3 butadiene and acrylonitrile.

[0036] In some other embodiments of the present invention, the polymeric rubber comprises an elastomeric terpolymer derived from a conjugated diene, a vinyl aromatic monomer, and a vinyl nitrile monomer. For example, in some embodiments of the present invention, the polymeric rubber is an elastomeric terpolymer comprising polymeric units derived from a styrene, 1,3 butadiene, and acrylonitrile copolymer.

[0037] Preferably, the polymeric rubber may be selected from polybutadiene, elastomeric copolymers comprising butadiene and styrene, elastomeric copolymers comprising butadiene and acrylonitrile, and elastomeric terpolymers comprising styrene-butadiene-acrylonitrile. Preferably, the polymeric rubber is polybutadiene.

[0038] The polymeric rubber can be prepared using known polymerization processes, such as bulk polymerization processes, solution polymerization processes, or emulsion polymerization processes. In some non-limiting embodiments of the present invention, the polymeric rubber can be prepared by an aqueous emulsion polymerization process in the presence of a free radical initiator, such as an azonitrile initiator, an organic peroxide initiator, a persulfate initiator, or a redox initiator system, and optionally in the presence of a chain transfer agent, such as an alkyl mercaptan.

[0039] In some embodiments of the present invention, the graft thermoplastic copolymer (C) is, for example, i. a vinyl aromatic monomer selected from styrene, α-methylstyrene, dibromostyrene, vinyl toluene, vinyl xylene, butyl styrene, p-hydroxystyrene, methoxystyrene, or any combination thereof, preferably, the vinyl aromatic monomer is styrene; ii. a vinyl nitrile monomer selected from acrylonitrile, methacrylonitrile, ethacrylonitrile, or a combination thereof, preferably, the vinyl nitrile monomer is acrylonitrile; and iii. A (meth)acrylic monomer selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, and decyl methacrylate, preferably, the (meth)acrylic monomer is methyl methacrylate (MMA).

[0040] The graft thermoplastic copolymer (C) may be selected, for example, from styrene / acrylonitrile copolymer, alpha-methylstyrene / acrylonitrile copolymer, styrene / methyl methacrylate / acrylonitrile / copolymer, and alpha-methylstyrene / acrylonitrile / methyl methacrylate copolymer, preferably the graft thermoplastic copolymer (C) may be a styrene / methyl methacrylate / acrylonitrile / copolymer.

[0041] Thus, the rubber-modified thermoplastic polymer (E) is a graft thermoplastic copolymer (C) selected from styrene / acrylonitrile copolymer, alpha-methylstyrene / acrylonitrile copolymer, styrene / methyl methacrylate / acrylonitrile / copolymer, and alpha-methylstyrene / acrylonitrile / methyl methacrylate copolymer, preferably the graft thermoplastic copolymer (C) is styrene / methyl methacrylate / acrylonitrile / copolymer; and a polymeric rubber selected from polybutadiene, elastomeric copolymers comprising polymeric units derived from 1,3-butadiene and styrene, elastomeric copolymers comprising polymeric units derived from butadiene and acrylonitrile, and elastomeric terpolymers comprising polymeric units derived from styrene butadiene and acrylonitrile, preferably the polymeric rubber is selected from polybutadiene, elastomeric copolymers comprising polymeric units derived from 1,3-butadiene and styrene, elastomeric copolymers comprising polymeric units derived from butadiene and acrylonitrile, more preferably the polymeric rubber is polybutadiene.

[0042] Preferably, the graft thermoplastic copolymer (C) is a styrene / methyl methacrylate / acrylonitrile / copolymer and the polymer rubber is polybutadiene.

[0043] Preferably, the rubber modified thermoplastic polymer (E) is a polybutadiene grafted with styrene / methyl methacrylate / acrylonitrile / copolymer.

[0044] Preferably, the rubber-modified thermoplastic polymer (E) may comprise ≧55.0 wt.% and ≦75.0 wt.%, preferably ≧57.0 wt.% and ≦70.0 wt.%, preferably ≧60.0 wt.% and ≦65.0 wt.%, preferably ≧60.0 wt.% and ≦63.0 wt.% of polymer units derived from conjugated dienes selected from 1,3-butadiene, isoprene, 1,3-heptadiene, methyl-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, or any combination thereof, based on the total weight of the rubber-modified thermoplastic polymer (E). Preferably, the conjugated diene is 1,3-butadiene.

[0045] The rubber-modified thermoplastic polymer (E) is, based on the total weight of the rubber-modified thermoplastic polymer (E), a. ≧55.0% and ≦75.0% by weight, preferably ≧57.0% and ≦73.0% by weight, preferably ≧60.0% and ≦65.0% by weight, preferably ≧60.0% and ≦63.0% by weight of polymeric units derived from conjugated dienes selected from 1,3-butadiene, isoprene, 1,3-heptadiene, methyl-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, or any combination thereof; b. ≧19.0% and ≦30.0% by weight, preferably ≧20.0% and ≦29.0% by weight, of polymeric units derived from vinyl aromatic monomers; c. ≧5.0% and ≦12.0% by weight, preferably ≧6.0% and ≦10.0% by weight, of polymeric units derived from vinyl nitrile monomers; d. ≧1.0% and ≦5.0, preferably ≧1.0% and ≦3.0% by weight of polymer units derived from (meth)acrylic monomers.

[0046] Preferably, the rubber modified thermoplastic polymer (E) is, based on the total weight of the rubber modified thermoplastic polymer (E), a. ≧55.0% and ≦75.0% by weight, preferably ≧57.0% and ≦73.0% by weight, preferably ≧60.0% and ≦65.0% by weight, preferably ≧60.0% and ≦63.0% by weight of polymer units derived from 1,3-butadiene; b. ≧19.0% and ≦30.0% by weight, preferably ≧20.0% and ≦29.0% by weight, of polymer units derived from styrene; c. ≧5.0% and ≦12.0% by weight, preferably ≧6.0% and ≦10.0% by weight, of polymer units derived from acrylonitrile; d. ≧1.0% and ≦5.0, preferably ≧1.0% and ≦3.0% by weight of polymer units derived from methyl methacrylate (MMA).

[0047] The copolymer (A) and the grafted thermoplastic copolymer (C) can be prepared according to any known polymerization process, such as bulk polymerization, emulsion polymerization, suspension polymerization, or a combination thereof. Furthermore, during the preparation of the rubber-modified thermoplastic polymer (E), the grafted thermoplastic copolymer (C) can be chemically bonded, i.e., "grafted" to the polymer rubber, via reaction with unsaturated sites present in the polymer rubber. The grafting reaction can be carried out in a batch, continuous, or semi-continuous process.

[0048] The rubber-modified thermoplastic polymer (E) may contain a portion of the grafted thermoplastic copolymer (C) that is not chemically grafted to the polymer rubber. The portion of the grafted thermoplastic copolymer (C) that is not chemically grafted to the polymer rubber may be referred to as "free thermoplastic copolymer (C)". For example, the rubber-modified thermoplastic polymer (E) may contain ≦15.0 wt%, preferably ≦10.0 wt%, preferably ≦5.0 wt%, preferably ≦2.0 wt% of the grafted thermoplastic copolymer (C) that is not chemically grafted to the polymer rubber "free thermoplastic copolymer (C)".

[0049] Thus, in some embodiments of the present invention, the rubber-modified thermoplastic polymer (E) may be, for example, based on the total weight of the rubber-modified thermoplastic polymer (E): a. ≧55.0wt% and ≦75.0wt%, preferably ≧57.0wt% and ≦73.0wt%, preferably ≧60.0wt% and ≦65.0wt%, preferably ≧60.0wt% and ≦63.0wt% of a polymer rubber; b. ≧25.0wt% and ≦35.0wt%, preferably ≧25.0wt% and ≦30.0wt% of a graft thermoplastic copolymer (C); c. ≧0.0% and ≦15.0% by weight, preferably ≧5.0% and ≦10.0% by weight, of free thermoplastic copolymer (C).

[0050] Thermoplastic polymer composition: The thermoplastic polymer composition of the present invention has a suitable content of polymer units derived from conjugated dienes to form polymeric rubber present in the thermoplastic polymer composition.For example, the thermoplastic polymer composition may contain ≧17.1wt% and ≦38.0wt%, preferably ≧17.1wt% and ≦36.0wt%, preferably ≧17.1wt% and ≦30.0wt%, preferably ≧17.1wt% and ≦23.0wt%, preferably ≧18.0wt% and ≦23.0wt% of polymer units derived from conjugated dienes selected from 1,3-butadiene, isoprene, 1,3-heptadiene, methyl-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, or any combination thereof, based on the total weight of the thermoplastic polymer composition.Preferably, the conjugated diene is 1,3-butadiene.

[0051] Preferably, the thermoplastic polymer composition may comprise ≧17.1 wt.-% and ≦38.0 wt.-%, preferably ≧17.1 wt.-% and ≦36.0 wt.-%, preferably ≧17.1 wt.-% and ≦30.0 wt.-%, preferably ≧17.1 wt.-% and ≦23.0 wt.-%, preferably ≧18.0 wt.-% and ≦23.0 wt.-%, based on the total weight of the thermoplastic polymer composition, of polymer units derived from 1,3-butadiene.

[0052] Preferably, the thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. ≧17.1% and ≦38.0% by weight, preferably ≧17.1% and ≦36.0% by weight, preferably ≧17.1% and ≦30.0% by weight, preferably ≧17.1% and ≦23.0% by weight, preferably ≧18.0% and ≦23.0% by weight of polymer units derived from 1,3-butadiene; b. ≧55.0% and ≦65.0% by weight, preferably ≧55.0% and ≦63.0% by weight, of polymer units derived from styrene; c. ≧5.0% and ≦22.0% by weight, preferably ≧7.0% and ≦22.0% by weight, preferably ≧10.0% and ≦22.0% by weight, preferably ≧15.0% and ≦22.0% by weight of polymer units derived from acrylonitrile; d. >0.0% and ≦1.0% by weight, preferably >0.0% and ≦0.8% by weight, of polymer units derived from methyl methacrylate (MMA).

[0053] The content of polymeric units of the thermoplastic polymer composition and / or the rubber-modified thermoplastic polymer (E) can be measured, for example, by Fourier transform infrared spectroscopy (FT-IR). Fourier transform infrared spectroscopy can be performed, for example, according to ASTM E168-99.

[0054] The thermoplastic polymer composition may include one or more stabilizing additives, such as acid scavengers, lubricants, antioxidants, processing stabilizers, and combinations thereof. Preferably, the stabilizing additive may be a combination of an acid scavenger and a lubricant.

[0055] The stabilizing additive may be present in the thermoplastic polymer composition in an appropriate proportion, for example. The thermoplastic polymer composition may comprise, for example, a stabilizing additive selected from magnesium oxide (MgO), wax, stabilizer, colorant, processing stabilizer, or any combination thereof, with ≦1.2 wt%, preferably ≦1.0 wt%, preferably ≦0.8 wt%, based on the total weight of the thermoplastic polymer composition, and preferably the stabilizing additive is a combination of magnesium oxide (MgO) and wax. Preferably, the thermoplastic polymer composition may comprise a stabilizing additive in an amount of ≧0.0 wt% and 1.0 wt%, preferably ≧0.0 wt% and 0.8 wt%, based on the total weight of the thermoplastic polymer composition.

[0056] The magnesium oxide may be present, for example, in an amount of ≧0.01 wt.% and ≦0.2 wt.%, preferably ≧0.08 wt.% and ≦0.18 wt.%, preferably ≧0.1 wt.% and ≦0.15 wt.%, based on the total weight of the thermoplastic polymer composition. The wax may be present, for example, in an amount of ≧0.10 wt.% and ≦1.0 wt.%, preferably ≧0.3 wt.% and ≦0.5 wt.%, preferably ≧0.4 wt.% and ≦0.5 wt.%, based on the total weight of the thermoplastic polymer composition. The wax may be, for example, ethylene bis stearamide (EBS) wax.

[0057] In some embodiments of the present invention, the thermoplastic polymer composition may be, for example, substantially free of silicone oil.Preferably, the thermoplastic polymer composition may comprise ≦0.001 wt%, preferably ≦0.0001 wt%, preferably zero (0.0) wt% silicone oil, based on the total weight of the thermoplastic polymer composition.The silicone oil may, for example, comprise any compound that comprises one or more siloxane repeat units.Non-limiting examples of silicone oil may include, for example, polydimethylsiloxane, methylhydrogenpolysiloxane, and polymethylphenylsiloxane, and any derivative thereof.

[0058] Preferably, the thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. ≧50.0wt% and ≦70.0wt%, preferably ≧60.0wt% and ≦69.0wt%, preferably ≧65.0wt% and ≦69.0wt%, of a styrene-acrylonitrile copolymer; b. ≧30.0wt% and≦50.0wt%, preferably ≧31.0wt% and≦40.0wt%, preferably ≧31.0wt% and≦35.0wt% of a styrene / methyl methacrylate / acrylonitrile / copolymer grafted polybutadiene; c. ≧0.0% and ≦1.0% by weight, preferably ≧0.0% and 0.8% by weight of a stabilizing additive.

[0059] Preferably, the thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. a copolymer (A) of ≧50.0% and ≦68.89% by weight, preferably ≧60.0% and ≦68.89% by weight, preferably ≧65.0% and ≦68.89% by weight, wherein the copolymer (A) comprises a styrene-acrylonitrile copolymer (SAN); b. ≧31.0wt% and ≦48.8wt%, preferably ≧31.0wt% and ≦39.0wt%, preferably ≧31.0wt% and ≦34.0wt% of a rubber-modified thermoplastic polymer (E), preferably the rubber-modified thermoplastic polymer (E) comprises a polybutadiene grafted with a styrene / methyl methacrylate / acrylonitrile / copolymer; c. Magnesium oxide (MgO) of ≧0.01% and ≦0.2%, preferably ≧0.08% and ≦0.18%, preferably ≧0.1% and ≦0.15%, by weight; d. ≧0.10% and ≦1.0%, preferably ≧0.3% and ≦0.5%, preferably ≧0.4% and ≦0.5% by weight of wax.

[0060] Preferably, the thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. ≧50.0% and ≦68.89% by weight of copolymer (A), the copolymer (A) comprising styrene-acrylonitrile copolymer (SAN); b. ≧31.0 wt.% and ≦48.8 wt.% of a rubber-modified thermoplastic polymer (E), the rubber-modified thermoplastic polymer (E) comprising polybutadiene grafted with styrene / methyl methacrylate / acrylonitrile / copolymer; c. ≧0.01% and ≦0.2% by weight of magnesium oxide (MgO); d. ≧0.10% by weight and ≦1.0% by weight of a wax; The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg, of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, and further, the thermoplastic polymer composition may contain zero (0.0) wt. % of silicone oil, based on the total weight of the thermoplastic polymer composition.

[0061] Preferably, the thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. ≧60.0% and ≦68.0% by weight of copolymer (A), the copolymer (A) comprising styrene-acrylonitrile copolymer (SAN); b. ≧31.0 wt.% and ≦39.0 wt.% of a rubber-modified thermoplastic polymer (E), the rubber-modified thermoplastic polymer (E) comprising polybutadiene grafted with styrene / methyl methacrylate / acrylonitrile / copolymer; c. ≧0.08% and ≦0.18% by weight of magnesium oxide (MgO); d. ≧0.3% by weight and ≦0.5% by weight of wax; The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg, of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, and further, the thermoplastic polymer composition may contain zero (0.0) wt. % of silicone oil, based on the total weight of the thermoplastic polymer composition.

[0062] Preferably, the thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. ≧65.35% and ≦68.0% by weight of copolymer (A), the copolymer (A) comprising styrene-acrylonitrile copolymer (SAN); b. ≧31.5 wt.% and ≦34.0 wt.% of a rubber-modified thermoplastic polymer (E), the rubber-modified thermoplastic polymer (E) comprising polybutadiene grafted with styrene / methyl methacrylate / acrylonitrile / copolymer; c. ≧0.1% and ≦0.15% by weight of magnesium oxide (MgO); d. ≧0.4% by weight and ≦0.5% by weight of wax; The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg, of ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min, and further, the thermoplastic polymer composition may contain zero (0.0) wt. % of silicone oil, based on the total weight of the thermoplastic polymer composition.

[0063] Properties of the thermoplastic polymer composition: In some aspects of the present invention, the thermoplastic polymer composition achieves a desired balance of flow and impact properties. Advantageously, in some aspects of the present invention, the thermoplastic polymer composition of the present invention is substantially free of silicone oil, yet achieves a desired balance of flow and impact properties. For example, in some embodiments of the present invention, the thermoplastic polymer of the present invention is a. a melt flow rate, measured according to ISO 1133 (2005) at 220°C using a load of 10.0 kg, of ≧25.0 g / 10 min and ≦50.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦50.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦40.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦35.0 g / 10 min; b. ≥ 15.0 KJ / m, measured at 23°C according to ISO180 (2006) 2 And ≦30.0KJ / m 2 , preferably ≧18.0 KJ / m 2 And ≦25.0KJ / m 2 , preferably ≧20.0KJ / m 2 And ≦23.0KJ / m 2 and the Izod notched impact strength.

[0064] Alternatively, the flow properties of a polymer composition may be evaluated based on its melt volume flow rate (MVR) property. For example, a thermoplastic polymer should have a melt volume flow rate (MVR) of ≥ 22.0 cm3, measured at 220°C using a load of 10.0 kg, according to ISO 1133 (2005). 3 / 10 minutes or less than 40.0cm 3 / 10 min, preferably ≥ 25.0 cm 3 / 10 minutes or less than 35.0cm 3 / 10 min, preferably ≥ 27.0 cm 3 / 10 minutes or less than 30.0 cm 3 / 10min melt volume flow rate.

[0065] In one embodiment of the present invention, the thermoplastic polymer composition has a suitable mechanical property of tensile strain at break, which indicates the resistance of the polymeric material to deformation under the influence of an external force. For example, the thermoplastic polymer exhibits a tensile strain at break of ≧20.0% and ≦30.0, preferably ≧21.0% and ≦27.0%, preferably ≧21.0% and ≦25.0%, as measured according to ISO527-1(2019).

[0066] In a preferred aspect of the present invention, the thermoplastic polymer composition exhibits an excellent combination of mechanical and flow properties. Preferably, in some embodiments of the present invention, the thermoplastic polymer composition comprises: a. a melt flow rate, measured according to ISO 1133 (2005) at 220°C using a load of 10.0 kg, of ≧25.0 g / 10 min and ≦50.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦50.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦40.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦35.0 g / 10 min; b. ≥ 15.0 KJ / m, measured at 23°C according to ISO180 (2006) 2 And ≦30.0KJ / m 2 , preferably ≧18.0 KJ / m 2 And ≦25.0KJ / m 2 , preferably ≧20.0KJ / m 2 And ≦23.0KJ / m 2 and the Izod notched impact strength of c. ≥ 22.0 cm, measured at 220°C using a load of 10.0 kg, in accordance with ISO 1133 (2005) 3 / 10 minutes or less than 40.0cm 3 / 10 min, preferably ≥ 25.0 cm 3 / 10 minutes or less than 35.0cm 3 / 10 min, preferably ≥ 27.0 cm 3 / 10 minutes or less than 30.0 cm 3 / 10 min melt volume flow rate and d. A tensile strain at break, measured according to ISO 527-1 (2019), of ≧20.0% and ≦30.0, preferably ≧21.0% and ≦27.0%, preferably ≧21.0% and ≦25.0%.

[0067] Evaluations of the Izod notched impact strength and tensile strain at break of the thermoplastic polymer compositions may be determined, for example, using injection molded test samples comprising the thermoplastic polymer compositions according to embodiments of the present invention.

[0068] Process for preparing a thermoplastic polymer composition: In some aspects of the present invention, the present invention is directed to a method for preparing the thermoplastic polymer composition of the present invention. The method for preparing the thermoplastic polymer composition may, for example, include a) melt-kneading a set of components including copolymer (A), rubber-modified thermoplastic polymer (E), and optionally one or more stabilizing additives in an extruder to form a precursor composition, and then b) extruding the precursor composition at a melt temperature of ≦300°C, preferably ≦280°C, to form a thermoplastic polymer composition. Preferably, the one or more stabilizing additives is a combination of magnesium oxide (MgO) and wax. The extrusion process may, for example, include extruding the precursor composition through different extrusion zones operating at a melt temperature of ≦300°C, preferably ≦280°C.

[0069] The process including melt blending and extrusion can be carried out using a single screw extruder, a twin screw extruder, and a Banbury mixer. A twin screw extruder is preferably used for the melt blending and extrusion process according to one embodiment of the present invention. In one aspect of the present invention, the precursor composition is mixed homogeneously and then extruded using a twin screw extruder to obtain a thermoplastic polymer composition in the form of pellets.

[0070] In one aspect of the present invention, the present invention is directed to an article comprising the thermoplastic polymer composition comprising the thermoplastic polymer composition of the present invention.Preferably, the article is an injection molded article.Preferably, such an article may comprise ≧90.0 wt%, preferably ≧95.0 wt%, preferably ≧99.0 wt%, preferably 100.0 wt%, based on the total weight of the article.Non-limiting examples of such injection molded articles may include automotive parts, electrical products, consumer goods, and sporting goods.

[0071] Preferably, the present invention is directed to an article comprising a thermoplastic polymer composition comprising: a. ≧50.0wt% and ≦70.0wt%, preferably ≧60.0wt% and ≦69.0wt%, preferably ≧65.0wt% and ≦69.0wt%, based on the total weight of the thermoplastic polymer composition, of a copolymer (A) comprising polymeric units derived from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers; b. ≧30.0wt% and ≦50.0wt%, preferably ≧31.0wt% and ≦40.0wt%, preferably ≧31.0wt% and ≦35.0wt% of a rubber-modified thermoplastic polymer (E), based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0wt%, preferably ≧57.0wt%, based on the total weight of the rubber-modified thermoplastic polymer (E).

[0072] Preferably, the copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. and a load of 1.2 kg, of ≧7.0 g / 10 min and ≦20.0 g / 10 min, preferably ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min.

[0073] Specific examples illustrating some of the embodiments of the present invention are provided below. These examples are for illustrative purposes only and are not intended to limit the present invention. It should be understood that the embodiments and aspects disclosed herein are not mutually exclusive, and such aspects and embodiments can be combined in any manner. Those skilled in the art will readily recognize parameters that can be changed or modified to produce essentially the same results. EXAMPLES

[0074] Purpose: For the purpose of illustrating the present invention, four different thermoplastic compositions were prepared. The samples labeled "IE" represent inventive thermoplastic polymers according to embodiments of the present invention, and the samples labeled "CE1", "CE2", and "CE3" are comparative thermoplastic polymer compositions.

[0075] Materials: The following materials were used: [Table 1]

[0076] The copolymer (A) and the rubber modified thermoplastic polymer (E) were mixed together through the process of melt mixing and extrusion. The general process steps include melt mixing the copolymer (A), the rubber modified thermoplastic polymer (E), and the stabilizing additives including magnesium oxide (MgO) and EBS wax in a twin screw extruder to form the resulting precursor composition. Silicone oil was added to sample CE1 along with other ingredients. The precursor composition was then extruded to obtain a thermoplastic polymer composition in the form of pellets. The process included a 133 mm twin screw extruder equipped with an automatic screen changer, a strand die head, a water slide system, a pelletizer, a pellet drying system, and a pellet screener system.

[0077] During the extrusion process, the polymer melt is forced through a die hole, pulled through a water slide system for proper cooling and hardening, and then passed to a pelletizer to form pellets. The polymer pellets are subsequently dried in a pellet drying system and then discharged onto a rotary motion screen to remove undersized and oversized pellets.

[0078] The conditions for extrusion and melt-kneading were as follows. [Table 2]

[0079] The resulting thermoplastic polymer compositions are classified below in terms of inventive compositions (IE) and comparative compositions (CE1, CE2, and CE3). [Table 3]

[0080] The resulting samples were evaluated for flow properties and mechanical properties of impact and tensile break strain. The following test parameters were used:

[0081] The melt flow rates (MFR) of the samples obtained from (IE and CE1–CE3) were measured at 220 °C using a load of 10.0 kg according to ISO 1133 (2005).

[0082] The melt volume-flow rates (MVRs) of the samples obtained from (IE and CE1–CE3) were measured at 220 °C using a load of 10.0 kg according to ISO 1133 (2005).

[0083] Izod notched impact strength was measured at 23°C according to ISO180 (2006). For Izod notched impact strength testing, samples (sample dimensions 80x10x4.0mm) were prepared by injection molding pellets containing thermoplastic polymer compositions (IE and CE1-CE3). During the injection molding process, the temperature profile was maintained at 220°C, 230°C, 230°C, and 230°C (Zone 1-Zone 4). The temperatures of the feed zone, nozzle, and mold section were maintained at 30°C, 230°C, and 60°C, respectively.

[0084] Tensile strain at break was measured on injection molded samples containing the thermoplastic polymer composition at a test speed of 50 mm / min according to ISO 527-1 (2019).

[0085] Results: The test results of the samples are shown in the table below. [Table 4]

[0086] From the data obtained from the above table, it is clear that only when the copolymer (A) and the rubber-modified thermoplastic polymer (E) according to the embodiment of the present invention are combined in a purposeful manner, a polymer composition having a desired balance between flow properties and mechanical properties is obtained. For example, it is clear that the composition of the present invention (IE) and the comparative composition (CE1) use the same copolymer (A) (sample SAN581) and the same rubber-modified thermoplastic polymer (E), but the ratios of these components are different, which play a role in imparting the desired balance between impact properties and flow properties. Specifically, it is observed that the composition of the present invention IE exhibits higher impact properties and tensile strain properties compared to the comparative compound CE1, while still maintaining sufficiently high flow properties. Furthermore, compared to the comparative composition CE1, the composition of the present invention IE can improve the balance between flow properties and mechanical properties without adding silicone oil.

[0087] The improved balance between flow and mechanical properties of the composition IE according to the invention is also evident from the corresponding data obtained for comparative compositions CE2 and CE3. Furthermore, the composition IE according to the invention shows improvements in both mechanical properties (impact and tensile strain) and flow properties (melt flow rate and melt volume flow rate) compared to the comparative composition CE2.

[0088] Thus, thermoplastic compositions IE having one or more characteristics according to embodiments of the present invention exhibit a desirable balance of mechanical and flow properties when compared to comparative samples CE1-CE3. The improved flow properties impart better processability to the polymer, while the mechanical properties of the polymer impart desirable impact and tensile properties to articles prepared from such compositions.

Claims

1. 1. A thermoplastic polymer composition comprising: a. a copolymer (A) comprising ≧50.0 wt.% and ≦70.0 wt.%, preferably ≧60.0 wt.% and ≦69.0 wt.%, preferably ≧65.0 wt.% and ≦69.0 wt.%, based on the total weight of the thermoplastic polymer composition, of polymeric units derived from (i) vinyl aromatic monomers and (ii) vinyl nitrile monomers; b. A rubber-modified thermoplastic polymer (E) of ≧30.0 wt% and ≦50.0 wt%, preferably ≧31.0 wt% and ≦40.0 wt%, preferably ≧31.0 wt% and ≦35.0 wt%, based on the total weight of the thermoplastic polymer composition, the rubber-modified thermoplastic polymer (E) having a polymer rubber content of ≧55.0 wt%, preferably ≧57.0 wt%, based on the total weight of the rubber-modified thermoplastic polymer (E); The copolymer (A) has a melt flow rate, measured according to ISO 1133 (2005) at 230° C. under a load of 1.2 kg, of ≧7.0 g / 10 min and ≦20.0 g / 10 min, preferably ≧8.0 g / 10 min and ≦15.0 g / 10 min, preferably ≧9.0 g / 10 min and ≦11.0 g / 10 min.

2. The copolymer (A) is a. an average molecular weight (Mw) of ≧50,000 g / mol and ≦100,000 g / mol, preferably ≧80,000 g / mol and ≦100,000 g / mol, preferably ≧85,000 g / mol and ≦98,000 g / mol, preferably ≧93,000 g / mol and ≦97,000 g / mol, as measured by gel permeation chromatography according to ASTM D5296-11; b) ≧20.0wt% and ≦26.0wt%, preferably ≧22.0wt% and ≦26.0wt%, preferably ≧23.0wt% and ≦26.0wt%, of polymer units derived from vinyl nitrile monomers, based on the total weight of the copolymer (A).

3. 3. The thermoplastic polymer composition of claim 1 or 2, wherein the vinyl aromatic monomer is selected from styrene, alpha-methylstyrene, dibromostyrene, vinyl toluene, vinyl xylene, butylstyrene, p-hydroxystyrene, methoxystyrene, or any combination thereof, preferably, the vinyl aromatic monomer is selected from styrene, alpha-methylstyrene, or a combination thereof, more preferably, the vinyl aromatic monomer is styrene.

4. 4. The thermoplastic polymer composition of any one of claims 1 to 3, wherein the vinyl nitrile monomer is selected from acrylonitrile, alpha-chloroacrylonitrile, methacrylonitrile, ethacrylonitrile, or a combination thereof, preferably, the vinyl nitrile monomer is acrylonitrile.

5. The thermoplastic polymer composition according to any one of claims 1 to 4, wherein the copolymer (A) comprises a styrene-acrylonitrile copolymer (SAN).

6. The rubber-modified thermoplastic polymer (E) is a. a polymeric rubber, i. ≧90.0wt% and ≦100wt%, preferably ≧95.0wt% and ≦100wt%, based on the total weight of the polymer rubber, of polymer units derived from conjugated dienes, said conjugated dienes being selected from 1,3-butadiene, isoprene, 1,3-heptadiene, methyl-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, or any combination thereof, preferably said conjugated diene being selected from 1,3-butadiene, isoprene, or any combination thereof, more preferably said conjugated diene being 1,3-butadiene; ii. a polymeric rubber comprising ≧0.0 wt.% and ≦10.0 wt.%, preferably ≧0.0 wt.% and ≦5.0 wt.%, based on the total weight of the polymeric rubber, of polymeric units derived from vinyl aromatic monomers and / or vinyl nitrile monomers, wherein the vinyl aromatic monomers are selected from styrene, α-methylstyrene, or any combination thereof, and the vinyl nitrile monomer is acrylonitrile; b. a graft thermoplastic copolymer (C), said graft thermoplastic copolymer (C) being grafted to said polymer rubber, said graft thermoplastic copolymer (C) comprising: i. a vinyl aromatic monomer selected from styrene, α-methylstyrene, dibromostyrene, vinyl toluene, vinyl xylene, butyl styrene, p-hydroxystyrene, methoxystyrene, or any combination thereof, preferably, said vinyl aromatic monomer is styrene; ii. a vinyl nitrile monomer selected from acrylonitrile, methacrylonitrile, ethacrylonitrile, or a combination thereof, preferably, the vinyl nitrile monomer is acrylonitrile; iii. a graft thermoplastic copolymer (C) comprising polymer units derived from a (meth)acrylic monomer, optionally selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, decyl methacrylate, preferably said (meth)acrylic monomer being methyl methacrylate (MMA); 2. The thermoplastic polymer composition of claim 1, further comprising a polymer rubber content of ≧55.0 wt.% and ≦75.0 wt.%, preferably ≧57.0 wt.% and ≦70.0 wt.%, preferably ≧60.0 wt.% and ≦65.0 wt.%, preferably ≧60.0 wt.% and ≦63.0 wt.%, based on the total weight of the rubber modified thermoplastic polymer (E).

7. a. the graft thermoplastic copolymer (C) is selected from styrene / acrylonitrile copolymer, alpha-methylstyrene / acrylonitrile copolymer, styrene / methyl methacrylate / acrylonitrile copolymer, and alpha-methylstyrene / acrylonitrile / methyl methacrylate copolymer, preferably, the graft thermoplastic copolymer (C) is styrene / methyl methacrylate / acrylonitrile copolymer; The thermoplastic polymer composition according to claim 1 or 6, wherein the polymeric rubber is selected from polybutadiene, elastomeric copolymers comprising polymeric units derived from 1,3 butadiene and styrene, elastomeric copolymers comprising polymeric units derived from butadiene and acrylonitrile, and elastomeric terpolymers comprising polymeric units derived from styrene butadiene and acrylonitrile, preferably the polymeric rubber is selected from polybutadiene, elastomeric copolymers comprising polymeric units derived from 1,3 butadiene and styrene, elastomeric copolymers comprising polymeric units derived from butadiene and acrylonitrile, more preferably the polymeric rubber is polybutadiene.

8. 8. The thermoplastic polymer composition according to any one of claims 1 to 7, wherein the thermoplastic polymer composition comprises ≧17.1 wt.-% and ≦38.0 wt.-%, preferably ≧17.1 wt.-% and ≦36.0 wt.-%, preferably ≧17.1 wt.-% and ≦30.0 wt.-%, preferably ≧17.1 wt.-% and ≦23.0 wt.-%, preferably ≧18.0 wt.-% and ≦23.0 wt.-%, based on the total weight of the thermoplastic polymer composition, of polymer units derived from a conjugated diene selected from 1,3-butadiene, isoprene, 1,3-heptadiene, methyl-1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, or any combination thereof, preferably wherein the conjugated diene is 1,3-butadiene.

9. 9. The thermoplastic polymer composition according to any one of claims 1 to 8, wherein the thermoplastic polymer composition further comprises ≦1.2 wt.-%, preferably ≦1.0 wt.-%, preferably ≦0.8 wt.-%, of a stabilizing additive selected from magnesium oxide (MgO), a wax, a stabilizer, a colorant, a processing stabilizer, or any combination thereof, based on the total weight of the thermoplastic polymer composition, preferably the stabilizing additive is a combination of magnesium oxide (MgO) and a wax.

10. The thermoplastic polymer composition comprises, based on the total weight of the thermoplastic polymer composition: a. ≧50.0wt% and ≦68.89wt%, preferably ≧60.0wt% and ≦68.89wt%, preferably ≧65.0wt% and ≦68.89wt%, of said copolymer (A), preferably said copolymer (A) comprising styrene-acrylonitrile copolymer (SAN); b. ≧31.0wt% and ≦48.8wt%, preferably ≧31.0wt% and ≦39.0wt%, preferably ≧31.0wt% and ≦34.0wt% of the rubber-modified thermoplastic polymer (E), preferably ≧31.0wt% and ≦48.8wt%, preferably ≧31.0wt% and ≦39.0wt%, preferably ≧31.0wt% and ≦34.0wt% of a styrene / methyl methacrylate / acrylonitrile / copolymer-grafted polybutadiene; c. Magnesium oxide (MgO) of ≧0.01 wt. % and ≦0.2 wt. %, preferably ≧0.08 wt. % and ≦0.18 wt. %, preferably ≧0.1 wt. % and ≦0.15 wt. %; d. ≧0.10wt% and ≦1.0wt%, preferably ≧0.3wt% and ≦0.5wt%, preferably ≧0.4wt% and ≦0.5wt% of a wax.

11. 11. The thermoplastic polymer composition according to any one of claims 1 to 10, wherein the thermoplastic polymer composition further comprises ≦0.001 wt.-%, preferably ≦0.0001 wt.-%, preferably zero (0.0) wt.-% of a silicone oil, relative to the total weight of the thermoplastic polymer composition.

12. The thermoplastic polymer is a melt flow rate according to ISO 1133 (2005) of ≧25.0 g / 10 min and ≦50.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦50.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦40.0 g / 10 min, preferably ≧30.0 g / 10 min and ≦35.0 g / 10 min, measured at 220° C. using a load of 10.0 kg; b. ≥ 15.0 kJ / m, measured at 23°C according to ISO 180 (2006) ２ And ≦30.0 kJ / m ２ , preferably ≧18.0 kJ / m ２ And ≦25.0 kJ / m ２ , preferably ≧20.0 kJ / m ２ And ≦23.0 kJ / m ２ and an Izod notched impact strength of 0.1 to 0.5% by mass of the thermoplastic polymer composition of any one of claims 1 to 11.

13. A method for preparing a thermoplastic polymer composition according to any one of claims 1 to 12, said method comprising the steps of: a. melt-blending a set of ingredients comprising the copolymer (A), the rubber-modified thermoplastic polymer (E), and optionally one or more stabilizing additives in an extruder to form a precursor composition; b) extruding said precursor composition at a melt temperature of ≦300° C., preferably ≦280° C. to form said thermoplastic polymer composition.

14. An article comprising the thermoplastic polymer composition according to any one of claims 1 to 12, preferably said article being an injection moulded article.

15. Use of the thermoplastic polymer composition according to any one of claims 1 to 12 for improving the processability and mechanical properties of a polymer composition suitable for thermoplastic processing.

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