Polymer composition for co-extruding with PS (polystyrene) or PE (polyethylene) plastic to form multi-layer structural body

Abstract

The present invention provides a polymer composition for co-extrusion with PS or PE plastic to form a multilayer structure, comprising a hydrogenated vinyl aromatic block copolymer having a first hydrogenated styrene-butadiene block copolymer, a second hydrogenated styrene-butadiene block copolymer, and a hydrogenated styrene-isoprene / butadiene block copolymer, the hydrogenated vinyl aromatic block copolymer in the polymer composition accounts for 70 wt% to 95 wt% of the total weight of the polymer composition. Wherein the content of a vinyl structure of a butadiene repeating unit before hydrogenation of the second hydrogenated styrene-butadiene block copolymer is greater than the content of a vinyl structure of a butadiene repeating unit before hydrogenation of the first hydrogenated styrene-butadiene block copolymer; the weight ratio of the first hydrogenated styrene-butadiene block copolymer to the second hydrogenated styrene-butadiene block copolymer is 0.9 to 7, and the content of the hydrogenated styrene-isoprene / butadiene block copolymer is 10 wt% to 30 wt% of the total weight of the polymer composition; and a non-hydrogenated styrene-butadiene block copolymer, the content of which is 5 wt%-10 wt% of the total weight of the polymer composition.

Description

Technical Field

[0001] This invention relates to the technical field of plastic co-extrusion, specifically to a polymer composition containing a hydrogenated ethylene aromatic block copolymer, particularly for co-extruding with PS or PE plastics into a multilayer structure. Background Technology

[0002] PS (polystyrene) sheets are typically transparent and rigid, widely used in food packaging, disposable tableware, advertising billboards, architectural decoration, and model making. While PS sheets are hard and rigid, they lack toughness and are easily scratched or even cracked upon impact, limiting their application in scenarios requiring high durability and impact resistance. PE (polyethylene) sheets, especially HDPE (high-density polyethylene) sheets, have a relatively flexible surface and good impact resistance and durability, often used for packaging flexible products. However, PE sheets have a softer surface and are easily scratched; therefore, both PS and PE sheets require surface reinforcement treatment to improve scratch resistance and overall lifespan.

[0003] Existing technologies include multilayer sheets co-extruded from TPU (thermoplastic polyurethane) and PS, which effectively improve the scratch resistance of PS surfaces. The soft and elastic properties of TPU contribute to the excellent scratch resistance of these sheets. However, while TPU technology solves the problem of PS surfaces being easily scratched, it introduces new challenges—the high surface friction coefficient of TPU-PS co-extruded sheets increases resistance when stacking or sliding, resulting in a noticeable stickiness during operation and affecting the feel and user experience. Summary of the Invention

[0004] In view of the above, this invention aims to replace TPU with hydrogenated ethylene aromatic block copolymers in co-extrusion with PS or PE plastics to form multilayer polymer compositions. Hydrogenated ethylene aromatic block copolymers are generally softer than TPU, have a dry surface feel, do not exhibit the "sticky" feel common in TPU, and are less expensive, making them more suitable for cost-sensitive consumer markets. Furthermore, this material exhibits better resistance to acids, alkalis, and polar solvents than TPU, possessing higher chemical stability. However, the inventors encountered many problems when attempting to co-extrude hydrogenated ethylene aromatic block copolymers (such as the commonly used SEBS) with PS or PE, such as insufficient compatibility with PS or PE leading to delamination, insufficient hardness, or poor processing flowability. Research revealed that these problems stem from the inherent differences in chemical properties between SEBS and PS or PE, and cannot be solved by simply adjusting processing parameters.

[0005] This invention unexpectedly discovered a special formulation comprising three hydrogenated ethylene aromatic block copolymers and one non-hydrogenated styrene-butadiene block copolymer. This formulation allows for co-extrusion with PS or PE to form a multilayer structure that protects the surface properties of PS or PE, exhibits good hardness and appropriate processing flow, and provides sufficient peel strength between the co-extruded layers to ensure strong interfacial bonding.

[0006] In one embodiment, the present invention provides a polymer composition for co-extruded with PS or PE plastics into a multilayer structure, comprising a hydrogenated ethylene aromatic block copolymer having a first hydrogenated styrene-butadiene block copolymer, a second hydrogenated styrene-butadiene block copolymer, and a hydrogenated styrene-isoprene / butadiene block copolymer, wherein the hydrogenated ethylene aromatic block copolymer accounts for 70 wt% to 95 wt% of the total weight of the polymer composition, wherein the second hydrogenated styrene-butadiene block copolymer contains butadiene repeating units before hydrogenation. The content of the vinyl structure is greater than the content of the vinyl structure of the butadiene repeating unit before hydrogenation of the first hydrogenated styrene-butadiene block copolymer; the weight ratio of the first hydrogenated styrene-butadiene block copolymer to the second hydrogenated styrene-butadiene block copolymer is 0.9 to 7; the content of the hydrogenated styrene-isoprene / butadiene block copolymer is 10 wt% to 30 wt% of the total weight of the polymer composition; and the content of the non-hydrogenated styrene-butadiene block copolymer is 5 wt% to 10 wt% of the total weight of the polymer composition.

[0007] The first and second hydrogenated styrene-butadiene block copolymers referred to in this article have only styrene and butadiene as monomers before hydrogenation. The hydrogenated styrene-isoprene / butadiene block copolymers referred to in this article have at least styrene and isoprene as monomers before hydrogenation, and selectively include butadiene.

[0008] In one embodiment, the present invention provides a polymer composition as described above, characterized in that the hydrogenated ethylene aromatic block copolymer comprises only the first hydrogenated styrene-butadiene block copolymer, the second hydrogenated styrene-butadiene block copolymer, and the hydrogenated styrene-isoprene / butadiene block copolymer.

[0009] In one embodiment, the present invention provides a polymer composition as described above, characterized in that the first hydrogenated styrene-butadiene block copolymer and the second hydrogenated styrene-butadiene block copolymer of the polymer composition are free of blocks with controlled distribution of ethylene aromatics and conjugated dienes.

[0010] On the other hand, the present invention provides a multilayer structure comprising a layer formed of a polymer composition as described in any of the preceding claims.

[0011] In one embodiment, the present invention provides a multilayer structure as described above, characterized in that the multilayer structure includes a PE plastic layer or a PS plastic layer, the layer covering the PE plastic layer or the PS plastic layer.

[0012] In one embodiment, the present invention does not use SEBS-g-MAH (maleic anhydride-grafted styrene-ethylene-butene-styrene block copolymer) or tackifying resin, because sheets using SEBS-g-MAH or tackifying resin may lose their original transparency, and tackifying resin will increase the stickiness of the sheet surface, affecting the user experience or stacking and storage performance of the sheet.

[0013] The details of various aspects of the present invention will be described in detail below. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a multilayer structure of the present invention, taking a sheet containing three layers as an example.

[0015] Explanation of reference numerals in the attached figures:

[0016] 100 Three-layer sheet

[0017] 110 Outer layer

[0018] 120 Intermediate Layer

[0019] 130 Inner Layer Detailed Implementation

[0020] The following will illustrate the implementation of the present invention through specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. It should be understood that these different embodiments or examples are merely illustrative and not intended to limit the present invention. The present invention can be implemented or applied through other different embodiments. Those skilled in the art can modify and / or change the specific embodiments based on different implementation methods and applications to carry out the present invention without departing from its spirit and scope.

[0021] Methods for measuring physical properties

[0022] Vinyl structure content (wt%) of hydrogenated ethylene aromatic block copolymer: measured using a nuclear magnetic resonance analyzer, a measurement method well known to those skilled in the art.

[0023] Vinyl aromatic content (wt%) of hydrogenated ethylene aromatic block copolymers: measured using a nuclear magnetic resonance analyzer, a measurement method well known to those skilled in the art.

[0024] Weight-average molecular weight (Mw) of hydrogenated ethylene aromatic block copolymers: gel permeation chromatography is a method commonly used by those skilled in the art.

[0025] Shore hardness (HS): Measured according to ASTM D2240 standard.

[0026] Melt Flow Index (MFI): The particles are placed in a melt flow indexing machine. Test standard: ASTM D1238.

[0027] Peel strength (gf / inch): The test method for peel strength of adhesive tapes (GB / T 2792-2014) was used to simulate the self-adhesive unwinding force between the outer and inner layers of the wound film. First, the film was manually unwound, and six film samples (25mm wide x 350mm long) were prepared. One outer layer was overlapped on top of the area of ​​another inner layer, resulting in three sets of film samples. The overlapping film samples were then pressed against a steel cylindrical roller. The roller was covered with approximately 6mm thick rubber with a hardness of 80±5 Shore A and a mass of 2±0.1 kg. The roller speed was fixed at 300 mm / min. Each set of film samples underwent two back-and-forth roller presses. After 3 hours, a peel tester clamped both ends of the film sample, with a peel angle of 180 degrees and a machine speed set to 300 mm / min. The test was then started, and the peel strength data of the film sample was read by the instrument software.

[0028] Polymer Composition

[0029] As described above, this invention discloses a formulation (hereinafter referred to as a polymer composition) in which hydrogenated ethylene aromatic block copolymers account for 70 wt% to 95 wt% of the total weight of the polymer composition. The polymer composition comprises three hydrogenated ethylene aromatic block copolymers and one non-hydrogenated styrene-butadiene block copolymer. This formulation allows for co-extrusion with PS or PE to form a multilayer structure that protects the surface properties of PS or PE. The three hydrogenated ethylene aromatic block copolymers are a first hydrogenated styrene-butadiene block copolymer, a second hydrogenated styrene-butadiene block copolymer, and a hydrogenated styrene-isoprene / butadiene block copolymer. The weight ratio of the first hydrogenated styrene-butadiene block copolymer to the second hydrogenated styrene-butadiene block copolymer is 0.9 to 7, while the content of the hydrogenated styrene-isoprene / butadiene block copolymer is 10 wt% to 30 wt% of the total weight of the polymer composition. The content of the non-hydrogenated styrene-butadiene block copolymer is 5 wt% to 10 wt% of the total weight of the polymer composition. In a preferred embodiment, the content of the first hydrogenated styrene-butadiene block copolymer is 20 wt% to 70 wt% of the total weight of the polymer composition, and the content of the second hydrogenated styrene-butadiene block copolymer is 10 wt% to 30 wt% of the total weight of the polymer composition.

[0030] Hydrogenated ethylene aromatic block copolymer

[0031] Hydrogenated ethylene aromatic block copolymers refer to block copolymers containing hydrogenated ethylene aromatic monomers and conjugated diene monomers. Specific examples of ethylene aromatic monomers suitable for use in this invention include styrene, 4-tert-butylstyrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, vinyl naphthalene, N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-aminoethylstyrene, and mixtures thereof. Styrene is a preferred choice. The conjugated diene monomers applicable to this invention may be conjugated dienes containing 4 to 12 carbon atoms, specific examples including 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, and mixtures thereof, wherein 1,3-butadiene and isoprene are preferred choices. The first hydrogenated styrene-butadiene block copolymer, the second hydrogenated styrene-butadiene block copolymer, and the hydrogenated styrene-isoprene / butadiene block copolymer are all individually classified as hydrogenated ethylene aromatic block copolymers.

[0032] First hydrogenated styrene-butadiene block copolymer and second hydrogenated styrene-butadiene block copolymer

[0033] The difference between the first hydrogenated styrene-butadiene block copolymer and the second hydrogenated styrene-butadiene block copolymer lies in the fact that the vinyl content of the butadiene repeating unit before hydrogenation in the second hydrogenated styrene-butadiene block copolymer is greater than that in the first hydrogenated styrene-butadiene block copolymer. In a preferred embodiment, both the first and second hydrogenated styrene-butadiene block copolymers are selected from SEBS (styrene-ethylene-butene-styrene block copolymer) or SEB (styrene-ethylene-butene block copolymer). In a preferred embodiment, the vinyl content of the butadiene repeating unit before hydrogenation in the first hydrogenated styrene-butadiene block copolymer is 32 wt% to 50 wt%, and the vinyl content of the butadiene repeating unit before hydrogenation in the second hydrogenated styrene-butadiene block copolymer is 60 wt% to 80 wt%. In a preferred embodiment, the styrene content in the first hydrogenated styrene-butadiene block copolymer is 16 wt% to 28 wt%; the styrene content in the second hydrogenated styrene-butadiene block copolymer is 10 wt% to 20 wt%. In a preferred embodiment, the weight-average molecular weight of the second hydrogenated styrene-butadiene block copolymer is greater than that of the first hydrogenated styrene-butadiene block copolymer. In a preferred embodiment, the weight-average molecular weight of the first hydrogenated styrene-butadiene block copolymer ranges from 50,000 to 100,000, preferably from 60,000 to 80,000. In a preferred embodiment, the weight-average molecular weight of the second hydrogenated styrene-butadiene block copolymer ranges from 150,000 to 250,000, preferably from 180,000 to 210,000. In a preferred embodiment, the melt flow index of the first hydrogenated styrene-butadiene block copolymer is 20 to 60 g / 10 min (230°C, 2.16 kg), preferably 30 to 50 g / 10 min (230°C, 2.16 kg). In a preferred embodiment, the melt flow index of the second hydrogenated styrene-butadiene block copolymer is 2 to 5 g / 10 min (190°C, 2.16 kg). In a particularly preferred embodiment, both the first and second hydrogenated styrene-butadiene block copolymers are SEBS (styrene-ethylene-butene-styrene block copolymers).

[0034] Hydrogenated styrene-isoprene / butadiene block copolymer

[0035] In a preferred embodiment, the hydrogenated styrene-isoprene / butadiene block copolymer is selected from SEEPS (styrene-ethylene-ethylene-propylene-styrene block copolymer), SEPS (styrene-ethylene-propylene-styrene block copolymer), or SEP (styrene-ethylene-propylene block copolymer). In a preferred embodiment, the vinyl content of the isoprene repeating units and butadiene repeating units in the hydrogenated styrene-isoprene / butadiene block copolymer before hydrogenation is 30 wt% to 50 wt%. More specifically, the vinyl content of the hydrogenated styrene-isoprene / butadiene block copolymer before hydrogenation is 30 wt% to 50 wt% of the isoprene repeating units in the absence of butadiene, and 30 wt% to 50 wt% of both the isoprene and butadiene repeating units in the presence of butadiene. In a preferred embodiment, the styrene content in the hydrogenated styrene-isoprene / butadiene block copolymer is 30 wt% to 40 wt%. In a preferred embodiment, the weight-average molecular weight of the hydrogenated styrene-isoprene / butadiene block copolymer ranges from 70,000 to 140,000, preferably from 90,000 to 110,000. In a particularly preferred embodiment, the hydrogenated styrene-isoprene / butadiene block copolymer is specifically SEEPS (styrene-ethylene-ethylene-propylene-styrene block copolymer). In a preferred embodiment, Zhejiang Zhongli SEEPS-8533 is used. Non-hydrogenated styrene-butadiene block copolymer.

[0036] In a preferred embodiment, the non-hydrogenated styrene-butadiene block copolymer has a Shore hardness (D) of 60 to 70, a melt flow index (MFI) of 5 to 15 g / 10 min (200°C, 5 kg), and a weight-average molecular weight of 11,000 to 150,000. In a preferred embodiment, Chi Mei Corporation's PB-5903Q adhesive is used.

[0037] Other additives

[0038] The polymer composition of the present invention may be without processing oil, or may selectively contain processing oil, with the content being no more than 5 wt% of the total weight of the polymer composition. In one embodiment, the processing oil may, for example, comprise naphthenic oil, paraffinic oil, aromatic oil, natural oil, or derivatives thereof; however, the present invention is not limited thereto. In a preferred embodiment, the kinematic viscosity of the processing oil at 40°C is in the range of 30 to 40, and its paraffinic hydrocarbon carbon atom content is 60% to 70%, and its naphthenic hydrocarbon carbon atom content is 30% to 40%. In addition to processing oil, in other embodiments, the polymer composition of the present invention may contain other functional agents as needed, such as compatibilizers, antifogging agents, wear-resistant agents, internal lubricants, etc.

[0039] Multi-layer structure and its components

[0040] like Figure 1 As shown, the multilayer structure 100 of the present invention includes an outer layer 110, an inner layer 130, and an intermediate layer 120 located between the inner layer 130 and the outer layer 110. The thickness of the outer layer 110 ranges from 0.2 mm to 1 mm, the thickness of the inner layer 130 ranges from 0.2 mm to 1 mm, and the thickness of the intermediate layer 120 ranges from 1 mm to 2 mm. The sheet is one type of multilayer structure. In another embodiment, the multilayer structure may consist only of the outer layer 110 and the intermediate layer 120. The multilayer structure 100 can be used in any suitable application field of sheets made of PS (polystyrene) or PE (polyethylene) plastics. In a preferred embodiment, the admixtures of the outer layer 110 and the inner layer 130 are both the aforementioned polymer composition, and the intermediate layer 120 is PS or PE plastic. The multilayer structure 100 is formed by co-extrusion of the aforementioned polymer composition and PS / PE. The multilayer structure 100 of the specific embodiment of the present invention has the following characteristics: Shore hardness range of 75 to 90A, melt flow index (MFI) range of 10 to 35 g / 10min (200℃, 5Kg), and peel strength of not less than 5 kgf / mm.

[0041] In a preferred embodiment, the polystyrene used in this invention is general-purpose polystyrene (GPPS) or high-impact polystyrene (HIPS). General-purpose polystyrene is transparent and rigid, and typical grades include... 143E (melt flow index of 5 g / 10 min (200℃, 5 kg) and 666D (melt flow index of 8 g / 10 min (200℃, 5 kg)). Impact-resistant polystyrene is usually polystyrene with added rubber toughening agents to improve its toughness. It has higher toughness and impact resistance. Typical grades include... 158K (melt flow index of 3g / 10min (200℃, 5Kg)) 615C (melt flow index of 4 g / 10 min (200℃, 5 kg)). General-purpose polystyrene (GPPS) is a preferred embodiment of the present invention.

[0042] Polyethylene plastic

[0043] In preferred embodiments, the polyethylene types suitable for the sheets of this invention include linear low-density polyethylene (LLDPE), used for stretch films and industrial packaging films, with typical grades such as SABIC LLDPE 218W (melt flow index approximately 2 g / 10 min (190°C, 2.16 kg)) and LLDPE 7047 (melt flow index approximately 1 g / 10 min (190°C, 2.16 kg)); and high-density polyethylene (HDPE), which has better rigidity and chemical resistance, used for rigid sheets, with typical grades including HHM5502BN (melt flow index approximately 0.4 g / 10 min (190°C, 2.16 kg)). High-density polyethylene (HDPE) is a particularly preferred embodiment of this invention. Specific Implementation

[0045] The multilayer structure 100 of the specific embodiment of the present invention has the following characteristics: Shore hardness range of 75 to 90A, melt flow index (MFI) range of 10 to 35 g / 10min (200℃, 5Kg), and peel strength of not less than 5 kgf / mm.

[0046] Examples of the first hydrogenated styrene-butadiene block copolymer (SEBS-1)

[0047] In a 100-liter reactor, 48 kg of cyclohexane and 120 g of THF (tetrahydrofuran) were added. Then, 9.50 g of NBL (n-butyllithium) was added, followed by 690 g of styrene monomer to initiate the reaction. After the styrene monomer polymerization was complete, 4.89 kg of butadiene monomer was added. After the butadiene monomer polymerization was complete, another 690 g of styrene monomer was added. Once the styrene monomer polymerization was complete, an SBS triblock copolymer was formed. The polymerization of this polymer was terminated with methanol. 1000 g of the polymer solution of the SBS triblock copolymer prepared above was placed in a pressure-resistant hydrogenation reactor and maintained in a nitrogen atmosphere. At room temperature, 0.11 mmol of stabilizer was dissolved in 10 ml of cyclohexane; 0.055 mmol of bis(cyclopentadienyl)titanium dichloride was dispersed in 10 ml of cyclohexane; and 0.33 mmol of triisobutylaluminum was dissolved in 10 ml of cyclohexane. The above solutions were added to the SBS triblock copolymer, and hydrogen was injected at a pressure of 25 kg / cm², followed by hydrogenation at 80 °C until more than 95% of the butadiene double bonds were saturated. The resulting polymer was precipitated in water to form particles, which were then dried to obtain the product, designated SEBS-1. The measured vinyl content was 40.4 wt%, the styrene content was 23.6 wt%, the weight-average molecular weight was 68,000, and the melt flow index was 44.4 g / 10 min (230 °C, 2.16 kg).

[0048] Examples of second hydrogenated styrene-butadiene block copolymer (SEBS-2)

[0049] In a 100-liter reactor, 48 kg of cyclohexane and 50 g of ethylene glycol diethyl ether were added. 6 g of NBL (n-butyllithium) was then added, followed by 425 g of styrene monomer to initiate the reaction. After the styrene monomer polymerization was complete, 5.7 kg of butadiene monomer was added. After the butadiene monomer polymerization was complete, another 425 g of styrene monomer was added. Once the styrene monomer polymerization was complete, an SBS triblock copolymer was formed. The polymerization of this polymer was terminated with methanol. 1000 g of the polymer solution of the SBS triblock copolymer prepared above was placed in a pressure-resistant hydrogenation reactor and maintained in a nitrogen atmosphere. At room temperature, 0.11 mmol of stabilizer was dissolved in 10 ml of cyclohexane; 0.055 mmol of bis(cyclopentadienyl)titanium dichloride was dispersed in 10 ml of cyclohexane; and 0.33 mmol of triisobutylaluminum was dissolved in 10 ml of cyclohexane. The above solutions were added to the SBS triblock copolymer, and hydrogen was injected at a pressure of 25 kg / cm², followed by hydrogenation at 80 °C until more than 95% of the butadiene double bonds were saturated. The resulting polymer was precipitated in water to form particles, which were then dried to obtain the product, designated SEBS-2. The measured vinyl content was 77 wt%, the styrene content was 13 wt%, the weight-average molecular weight was 180,000, and the melt flow index was 3 g / 10 min (190 °C, 2.16 kg).

[0050] The proportions of the components in the above embodiments can be varied to formulate SEBS with various properties that meet the requirements.

[0051] Examples of fabricated multi-layer structures.

[0052] Example 1

[0053] Take 27 wt% SEBS-1, 30 wt% SEBS-2, and 30 wt% SEEPS-8533 (vinyl structure content 30-50 wt%, styrene content 30-35 wt%, weight average molecular weight 90,000-110,000, melt flow index <0.1 g / 10 min (230℃, 2.16 kg), Zhejiang Zhongli), and add 5 wt% paraffin oil. After mixing and standing for 4 hours, add 8 wt% PB-5903Q glue (weight average molecular weight 130,000, Chi Mei Industrial). Use a twin-screw extruder to mix and extrude pellets at 120-190℃ (i.e., polymer composition 1). Place the pellets at the injection molding machine feed inlet, set the temperature to 170-185℃, cool for 30 seconds, and then remove the molded specimens to test the physical properties. The particles of polymer composition 1 were placed at the feed inlet of a single-screw extruder, and the temperature was set to 200-280℃. They were then reacted with PS particles (…). 143E (melting point approximately 95℃, melt flow index 5g / 10min (200℃, 5Kg)) and PE particles (HHM5502BN, melting point approximately 132℃, melt flow index approximately 0.4g / 10min (190℃, 2.16Kg)) were co-extruded together to form a sheet. The material used in this case was used as the top layer, and PS / PE as the middle layer. Test pieces were cut into dumbbell shapes and stacked to a thickness of approximately 6mm. These were then tested on a hardness tester for HS (ASTM D2240), and then on cut strips for MFI (ASTM D1238) testing. The three-layer co-extruded sheet was then tested on an electronic tensile testing machine for peel strength. Other embodiments and comparative examples of this invention can be performed following the procedure in Example 1. The amounts of each component and the characteristics of the co-extruded sheets in each embodiment and comparative example are detailed in Tables 1 to 4. Values ​​in parentheses in the tables indicate that the standard requirements were not met.

[0054] Table 1

[0055]

[0056] Table 1 shows that Example 1 met the standards for hardness, melt flow rate, and peel strength, demonstrating that a polymer composition containing SEBS-1, SEBS-2, SEEPS-8533, and Q-adhesive-PB5903 can produce PS / PE co-extruded sheets with specifications meeting the standard requirements. Comparative Examples 1 to 7 lacked certain key components, resulting in performance failures to meet the standards.

[0057] Table 2

[0058]

[0059] As can be seen from Table 2, all physical properties of Examples 1 to 5 met the requirements, while the results of Comparative Examples 7 and 8 failed to meet the requirements. The SEBS-1 content range for achieving good performance is approximately 20-70 wt%, the SEBS-2 content range is 10-30 wt%, and the SEEPS content range is 10-30 wt%.

[0060] Table 3

[0061]

[0062] As shown in Table 3, the physical properties of Examples 4 and 6 met the standards, while Comparative Examples 9, 10, and 11 did not. The content of Q-adhesive-PB5903 significantly affected the physical properties of the sheet, with the standard content range being 5-10 wt%. Within this range, the sheet exhibited good hardness, melt flow rate, and peel strength. However, excessively low (e.g., Comparative Examples 9 and 10) or excessively high (e.g., Comparative Example 11) Q-adhesive-PB5903 content led to a decrease in peel strength, failing to meet the standard, indicating that an appropriate amount of Q-adhesive-PB5903 needs to be added to optimize the sheet performance.

[0063] Table 4

[0064]

[0065] As shown in Table 4, the physical properties of Examples 4, 7, and 8 all met the standards, while the results of Comparative Examples 12 and 13 failed to meet the requirements. The content of processing oil affects the physical properties of the sheets, and the content range that meets the standards is 0-5 wt%. When the content of processing oil is too high (such as 10 wt% and 20 wt% in Comparative Examples 12 and 13, respectively), the hardness decreases significantly, the melt flow rate is too high, and the peel strength is insufficient, thus failing to meet the standards.

[0066] The above description of specific embodiments is merely illustrative, and various formulations can be modified according to specific needs without departing from the scope of the invention. These specific embodiments are intended to illustrate, and not to limit, the invention disclosed herein. Therefore, it will be apparent to those skilled in the art that certain modifications can be made to the described torso device without departing from the scope of the appended claims.

Claims

1. A polymeric composition for co-extruded with PS or PE plastic into a multilayer structure, comprising: The hydrogenated ethylene aromatic block copolymer comprises a first hydrogenated styrene-butadiene block copolymer, a second hydrogenated styrene-butadiene block copolymer, and a hydrogenated styrene-isoprene / butadiene block copolymer, wherein the hydrogenated ethylene aromatic block copolymer accounts for 70 wt% to 95 wt% of the total weight of the polymer composition, wherein the vinyl content of the butadiene repeating unit before hydrogenation of the second hydrogenated styrene-butadiene block copolymer is greater than the vinyl content of the butadiene repeating unit before hydrogenation of the first hydrogenated styrene-butadiene block copolymer, the weight ratio of the first hydrogenated styrene-butadiene block copolymer to the second hydrogenated styrene-butadiene block copolymer is 0.9 to 7, and the content of the hydrogenated styrene-isoprene / butadiene block copolymer is 10 wt% to 30 wt% of the total weight of the polymer composition; and a non-hydrogenated styrene-butadiene block copolymer, the content of which is 5 wt% to 10 wt% of the total weight of the polymer composition.

2. The polymer composition as described in claim 1, characterized in that, The first hydrogenated styrene-butadiene block copolymer and the second hydrogenated styrene-butadiene block copolymer are selected from SEBS (styrene-ethylene-butene-styrene block copolymer) or SEB (styrene-ethylene-butene block copolymer), while the hydrogenated styrene-isoprene / butadiene block copolymer is selected from SEEPS (styrene-ethylene-ethylene-propylene-styrene block copolymer), SEPS (styrene-ethylene-propylene-styrene block copolymer), or SEP (styrene-ethylene-propylene block copolymer).

3. The polymer composition as described in claim 1, characterized in that, The vinyl content of the butadiene repeating unit in the first hydrogenated styrene-butadiene block copolymer before hydrogenation is 32wt% to 50wt%, and the vinyl content of the butadiene repeating unit in the second hydrogenated styrene-butadiene block copolymer before hydrogenation is 60wt% to 80wt%.

4. The polymer composition according to claim 1, characterized in that, The first hydrogenated styrene-butadiene block copolymer contains 16 wt% to 28 wt% styrene; the second hydrogenated styrene-butadiene block copolymer contains 10 wt% to 20 wt% styrene.

5. The polymer composition as described in claim 1, characterized in that, The vinyl content of the hydrogenated styrene-isoprene / butadiene block copolymer before hydrogenation is 30wt% to 50wt% of the isoprene repeating unit when butadiene is not present, and 30wt% to 50wt% of both the isoprene repeating unit and the butadiene repeating unit when butadiene is present.

6. The polymer composition according to claim 1, characterized in that, The styrene content in this hydrogenated styrene-isoprene / butadiene block copolymer is 30wt% to 40wt%.

7. The polymer composition according to claim 1, characterized in that, The weight-average molecular weight of the second hydrogenated styrene-butadiene block copolymer is greater than that of the first hydrogenated styrene-butadiene block copolymer.

8. The polymer composition as described in claim 1, characterized in that, The weight-average molecular weight of the first hydrogenated styrene-butadiene block copolymer ranges from 50,000 to 100,000.

9. The polymer composition according to claim 1, characterized in that, The weight-average molecular weight of the second hydrogenated styrene-butadiene block copolymer ranges from 150,000 to 250,000.

10. The polymer composition according to claim 1, characterized in that, The weight-average molecular weight of the hydrogenated styrene-isoprene / butadiene block copolymer ranges from 70,000 to 140,000.

11. The polymer composition according to claim 1, characterized in that, The content of the first hydrogenated styrene-butadiene block copolymer is 20wt% to 70wt% of the total weight of the polymer composition, and the content of the second hydrogenated styrene-butadiene block copolymer is 10wt% to 30wt% of the total weight of the polymer composition.

12. The polymer composition according to claim 1, characterized in that, The polymer composition further contains processing oil, which accounts for no more than 5 wt% of the total weight of the polymer composition.

13. The polymer composition according to claim 1, characterized in that, This polymer composition does not contain tackifying resins.

14. The polymer composition according to claim 1, characterized in that, The hydrogenated ethylene aromatic block copolymer contains only the first hydrogenated styrene-butadiene block copolymer, the second hydrogenated styrene-butadiene block copolymer, and the hydrogenated styrene-isoprene / butadiene block copolymer.

15. The polymer composition according to claim 1, characterized in that, The first hydrogenated styrene-butadiene block copolymer or the second hydrogenated styrene-butadiene block copolymer of the polymer composition is free of blocks with controlled distribution of ethylene aromatics and conjugated dienes.

16. The polymer composition according to claim 1, characterized in that, The non-hydrogenated styrene-butadiene block copolymer has a hardness range of Shore hardness D 60 to 70 and a melt flow index (MFI) range of 5 to 15 g / 10 min (200℃, 5Kg).

17. The polymer composition according to claim 12, characterized in that, The processing oil has a kinematic viscosity range of 30 to 40 at 40°C, and its paraffinic hydrocarbon carbon atom content is 60% to 70%, while its cycloalkanes carbon atom content is 30% to 40%.

18. A multilayer structure comprising a layer formed of a polymeric composition according to any one of claims 1 to 17.

19. The multilayer structure as described in claim 18, characterized in that, The multi-layer structure includes a PE plastic layer or a PS plastic layer, which covers the PE plastic layer or the PS plastic layer.

20. The multilayer structure as described in claim 18, characterized in that, The multilayer structure has a Shore hardness range of 75 to 90A, a melt flow index (MFI) range of 10 to 35 g / 10 min (200℃, 5Kg), and a peel strength of not less than 5 kgf / mm.

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