Butylbenzene transparent anti-impact resin for casting extrusion sheet and preparation method thereof

Abstract

The invention relates to the technical field of casting extrusion materials, and particularly discloses butylbenzene transparent anti-impact resin for casting extrusion sheets and a preparation method of the butylbenzene transparent anti-impact resin. The styrene-butadiene resin is of a star-shaped structure, styrene and butadiene serve as raw materials, n-butyllithium serves as an initiator, n-butyllithium is added in a two-step mode, composite coupling agents are adopted as coupling agents, one coupling agent is divinyl benzene (DVB), and the other coupling agent X has the functionality larger than or equal to 2 and comprises dichlorodimethylsilane, silicon tetrachloride and the like. The resin has wide molecular weight distribution so as to improve the flowing property of a product and reduce the melt viscosity, and is particularly suitable for being used as an extrusion material to be applied to impact-resistant products.

Description

Technical Field

[0001] The present invention relates to the technical field of cast extrusion materials, and specifically discloses a styrene-butadiene transparent impact-resistant resin for cast extrusion sheets and a preparation method thereof. Background Art

[0002] In the field of cast extrusion materials, styrene-butadiene resin, as an important polymer material, is widely used in the production of various products such as sheets, films, and packaging materials due to its good transparency, impact resistance, and processing performance. However, traditional styrene-butadiene resins still have some deficiencies in practical applications, which limit their further development and application.

[0003] The molecular weight distribution of traditional styrene-butadiene resins is relatively narrow, which results in poor flowability and prone to problems such as processing difficulties and uneven shaping during the cast extrusion process. Especially when producing thick sheets or products with complex shapes, the insufficient fluidity of the resin will seriously affect production efficiency and product quality. In addition, the melt viscosity of traditional styrene-butadiene resins is relatively high, which not only increases processing energy consumption but also may cause defects on the surface of the product, such as weld lines and silver streaks, affecting the appearance and mechanical properties of the product. The high melt viscosity also limits the application of the resin in high-speed extrusion or thin sheet production, and it is difficult to meet the requirements of modern industry for efficient, energy-saving, and high-quality production.

[0004] To solve the above problems, researchers have conducted a large number of explorations and improvements. For example, methods such as adjusting the raw material ratio, optimizing the polymerization process, adding plasticizers or modifiers are used to improve the performance of styrene-butadiene resins. However, these methods often have certain limitations, such as complex processing technology, increased cost, environmental unfriendliness, or negative impacts on other properties of the resin.

[0005] Therefore, developing a styrene-butadiene resin with high fluidity, low melt viscosity, and excellent impact resistance is of great significance for meeting the requirements of the cast extrusion materials field. Based on this background, the present invention proposes a styrene-butadiene transparent impact-resistant resin for cast extrusion sheets and a preparation method thereof, aiming to overcome the deficiencies of the existing technology and provide a new type of styrene-butadiene resin material with excellent performance, convenient processing, and controllable cost. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the existing technology and provide a styrene-butadiene transparent impact-resistant resin for cast extrusion sheets and a preparation method thereof.

[0007] In the first aspect, the present invention discloses a styrene-butadiene transparent impact-resistant resin for cast extrusion sheets, adopting the following technical scheme:

[0008] A styrene-butadiene transparent impact-resistant resin for cast extrusion sheets, wherein the styrene-butadiene resin composition comprises a first styrene-butadiene block copolymer and a second styrene-butadiene block copolymer;

[0009] The structural formula of the first styrene-butadiene block copolymer includes: Am-X1;

[0010] The structural formula of the second styrene-butadiene block copolymer includes: An-X2;

[0011] wherein A is a styrene butadiene block copolymer, m and n are integers, m≥3, n≥2, X1 is a first coupling agent, and X2 is a residue of a second coupling agent, whose functionality is ≥2;

[0012] The A is prepared by reacting styrene, butadiene and an initiator, and the first coupling agent is divinylbenzene.

[0013] Preferably, in the first butadiene styrene block copolymer and the second butadiene styrene block copolymer, the mass percentage of the structural unit of styrene is 60%-75%, and the mass percentage of the structural unit of butadiene is 25%-40%.

[0014] Preferably, the structural formula of the first butadiene-styrene block copolymer includes: (St1-L1-Bd1-L2-Bd2 / St2-Bd3)-DVB, wherein St1 is a polystyrene segment, Bd1 and Bd3 are polybutadiene segments, and Bd2 / St2 is a segment of random blocks of butadiene and styrene.

[0015] Preferably, the second coupling agent includes dimethyldichlorosilane or silicon tetrachloride; the structural formula of the second styrene-butadiene block copolymer includes: (St1-L1-Bd1-L2-Bd2 / St2-Bd3) n -X 2 , wherein St1 is a polystyrene segment, Bd1 and Bd3 are polybutadiene segments, and Bd2 / St2 are segments of random blocks of butadiene and styrene.

[0016] Preferably, the number average molecular weight of the first butadiene styrene block copolymer and the second butadiene styrene block copolymer is 30,000 to 200,000 g / mol.

[0017] Preferably, the styrene-butadiene resin composition further comprises an antioxidant and a lubricant; the lubricant comprises microcrystalline wax and / or zinc stearate.

[0018] Preferably, the styrene-butadiene resin composition further comprises an auxiliary agent.

[0019] Preferably, the auxiliary agents include antioxidants, lubricants and antioxidants.

[0020] Preferably, the lubricant comprises microcrystalline wax and / or zinc stearate.

[0021] In a second aspect, the present invention discloses a method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets, which adopts the following technical scheme:

[0022] A method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets comprises the following steps:

[0023] (1) mixing styrene, butadiene and an initiator, and reacting them to obtain a styrene butadiene block copolymer;

[0024] (2) mixing the styrene butadiene block copolymer obtained in step (1), the first coupling agent and the second coupling agent, reacting them, and adding a terminator to obtain the styrene butadiene resin composition.

[0025] Preferably, the step (1) comprises the following steps:

[0026] (S1) mixing a solvent, a regulator, a portion of styrene and a portion of an initiator, and reacting them to obtain a product a;

[0027] (S2) mixing the product a obtained in step (S1) with a portion of butadiene, and reacting them to obtain a product b;

[0028] (S3) mixing the product b obtained in step (S2) with the remaining initiator, part of butadiene and the remaining styrene, and reacting them to obtain a product c;

[0029] (S4) mixing the product c obtained in step (S3) and the remaining butadiene, and reacting them to obtain a product d;

[0030] (S5) mixing the product d obtained in step (S4) with the first coupling agent and the second coupling agent to react to obtain the styrene butadiene block copolymer.

[0031] Preferably, the solvent includes any one of cyclohexane, n-hexane or toluene, or a combination of at least two of them.

[0032] Preferably, the regulator comprises any one of tetrahydrofuran, tetramethylethylenediamine or diethanol dimethyl ether, or a combination of at least two thereof.

[0033] Preferably, the initiator comprises n-butyllithium.

[0034] Preferably, the molar amount of divinylbenzene DVB / molar amount of initiator is 0.1-20, preferably 0.5-5.

[0035] Preferably, the molar amount of the second coupling agent / the molar amount of the initiator is 0.05 to 1, preferably 0.1 to 0.5.

[0036] Preferably, based on the total mass of styrene being 100%, in step (S1), the mass percentage of the styrene in the part is 60-80%.

[0037] Preferably, based on the total mass of the initiator being 100%, in step (S1), the mass percentage of the initiator of the portion is 20 to 75%.

[0038] Preferably, based on the total mass of styrene being 100%, in step (S3), the mass percentage of the styrene in the part is 20-40%.

[0039] Preferably, based on 100% of the total mass of butadiene, in step (S2), the mass percentage of the butadiene in the portion is 10-25%.

[0040] Preferably, based on 100% of the total mass of butadiene, in step (S3), the mass percentage of the styrene in the portion is 40-70%.

[0041] Preferably, based on 100% of the total mass of butadiene, in step (S4), the mass percentage of the butadiene in the portion is 5-50%.

[0042] Preferably, the reactions in step (S1), step (S2), step (S3) and step (S4) are each independently carried out to a conversion rate ≥ 99%.

[0043] Preferably, in step (S1), step (S2), step (S3), step (S4) and step (S5), the reaction temperature is independently 40-95°C.

[0044] Preferably, in step (S1), step (S2), step (S3), step (S4) and step (S5), the reaction time is independently 20 min to 40 min.

[0045] Preferably, the terminator includes any one of methanol, isopropanol or water, or a combination of at least two of them.

[0046] Preferably, the process further comprises adding an auxiliary agent into the system after adding the terminator.

[0047] In a third aspect, the present invention discloses an application of a styrene-butadiene resin composition in impact-resistant products.

[0048] Compared with the prior art, the present invention has at least the following beneficial effects:

[0049] The styrene butadiene resin of the invention has a star-shaped structure, takes styrene and butadiene as raw materials, adopts a two-step adding method for the initiator, adopts a composite coupling agent for the coupling agent, one of which is divinylbenzene (DVB), and the other coupling agent has a functionality of X≥2. The styrene butadiene resin has a wide molecular weight distribution to improve the flowability of the product and reduce the melt viscosity, and is particularly suitable for the material of cast extrusion. DETAILED DESCRIPTION

[0050] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with specific implementation methods.

[0051] Example 1

[0052] A transparent butadiene-styrene impact-resistant resin for cast extrusion sheets and a preparation method thereof:

[0053] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, and then 787.5g of styrene was added, and 4.1g of butyl lithium was added at 45°C. 67.5g of butadiene was added 10min after the peak temperature of the reaction. After the polymerization reaction was completed, 10.5g of butyl lithium was added, and then 270g of butadiene and 262.5g of styrene were added at the same time. 20min after the peak temperature of the polymerization reaction, 112.5g of butadiene was added, and after the reaction was complete, 5.5g of divinylbenzene and 2.16g of silicon tetrachloride were added at the same time. 5g of isopropanol was added after 30min, and then an antioxidant was added to obtain a butadiene-styrene resin composition.

[0054] Example 2

[0055] A transparent butadiene-styrene impact-resistant resin for cast extrusion sheets and a preparation method thereof:

[0056] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, and then 787.5g of styrene was added, and 4.1g of butyl lithium was added at 45°C. 67.5g of butadiene was added 10min after the peak temperature of the reaction. After the polymerization reaction was completed, 10.5g of butyl lithium was added, and then 270g of butadiene and 262.5g of styrene were added at the same time. 20min after the peak temperature of the polymerization reaction, 112.5g of butadiene was added, and after the reaction was complete, 7.5g of divinylbenzene and 1.16g of silicon tetrachloride were added at the same time. 5g of isopropanol was added after 30min, and then an antioxidant was added to obtain a butadiene-styrene resin composition.

[0057] Example 3

[0058] A transparent butadiene-styrene impact-resistant resin for cast extrusion sheets and a preparation method thereof:

[0059] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, and then 787.5g of styrene was added, and 4.1g of butyl lithium was added at 45°C. 67.5g of butadiene was added 10min after the peak temperature of the reaction. After the polymerization reaction was completed, 10.5g of butyl lithium was added, and then 270g of butadiene and 262.5g of styrene were added at the same time. 20min after the peak temperature of the polymerization reaction, 112.5g of butadiene was added, and after the reaction was complete, 4.5g of divinylbenzene and 3.16g of silicon tetrachloride were added at the same time. 5g of isopropanol was added after 30min, and then an antioxidant was added to obtain a butadiene-styrene resin composition.

[0060] Example 4

[0061] The invention discloses an application of a styrene-butadiene resin composition in impact-resistant products, such as impact-resistant bottles, impact-resistant plates, etc.

[0062] Comparative Example 1

[0063] A styrene-butadiene resin and a preparation method thereof:

[0064] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, followed by 787.5g of styrene, 4.1g of butyl lithium was added at 45°C, 67.5g of butadiene was added 10min after the peak temperature of the reaction, 10.5g of butyl lithium was added after the polymerization reaction was completed, and then 270g of butadiene and 262.5g of styrene were added at the same time, 112.5g of butadiene was added 20min after the peak temperature of the polymerization reaction, and after the reaction was complete, 2.16g of silicon tetrachloride was added to obtain a butadiene-styrene resin composition.

[0065] Comparative Example 2

[0066] A styrene-butadiene resin and a preparation method thereof:

[0067] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, and then 787.5g of styrene was added, and 4.1g of butyl lithium was added at 45°C. 67.5g of butadiene was added 10min after the peak temperature of the reaction. After the polymerization reaction was completed, 10.5g of butyl lithium was added, and then 270g of butadiene and 262.5g of styrene were added at the same time. 20min after the peak temperature of the polymerization reaction, 112.5g of butadiene was added. After the reaction was complete, 5.5g of divinylbenzene DVB was added to obtain a butadiene-styrene resin composition.

[0068] Comparative Example 3

[0069] Compared with Example 1, the first coupling agent uses dichlorodimethylsilane instead of divinylbenzene DVB

[0070] A styrene-butadiene resin and a preparation method thereof:

[0071] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, and then 787.5g of styrene was added, and 4.1g of butyl lithium was added at 45°C. 67.5g of butadiene was added 10min after the peak temperature of the reaction. After the polymerization reaction was completed, 10.5g of butyl lithium was added, and then 270g of butadiene and 262.5g of styrene were added at the same time. 20min after the peak temperature of the polymerization reaction, 112.5g of butadiene was added, and after the reaction was complete, 2.0g of dichlorodimethylsilane and 3.16g of silicon tetrachloride were added at the same time. 5g of isopropanol was added after 30min, and then an antioxidant was added to obtain a butadiene-styrene resin composition.

[0072] Comparative Example 4

[0073] Compared with Example 1, the second coupling agent uses trimethylchlorosilane instead of silicon tetrachloride.

[0074] A styrene-butadiene resin and a preparation method thereof:

[0075] In a 10L stainless steel reactor with stirring, 4500g of cyclohexane was added, and then 787.5g of styrene was added, and 4.1g of butyl lithium was added at 45°C. 67.5g of butadiene was added 10min after the peak temperature of the reaction. After the polymerization reaction was completed, 10.5g of butyl lithium was added, and then 270g of butadiene and 262.5g of styrene were added at the same time. 20min after the peak temperature of the polymerization reaction, 112.5g of butadiene was added, and after the reaction was complete, 4.5g of divinylbenzene and 1.5g of trimethylsilyl chloride were added at the same time. 5g of isopropanol was added after 30min, and then an antioxidant was added to obtain a butadiene-styrene resin composition.

[0076] Performance Testing

[0077] The styrene-butadiene resin compositions prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to various performance tests, and the test results are as follows:

[0078]

[0079] It can be seen from the above test results that comparative examples 1-4 are not as ideal as example 1 in terms of flow properties and melt viscosity. The butadiene-styrene resin compositions of examples 1-3 have high flow properties and low melt viscosity, and are particularly suitable for use as cast extrusion materials. This indicates that the simultaneous use of the first coupling agent of divinylbenzene and the second coupling agent with a functionality ≥ 2 of the present invention has a significant impact on the performance of the butadiene-styrene resin composition.

[0080] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A transparent butadiene-styrene impact-resistant resin for cast extrusion sheets, characterized in that: The styrene-butadiene resin composition comprises a first styrene-butadiene block copolymer and a second styrene-butadiene block copolymer; The structural formula of the first styrene-butadiene block copolymer includes: Am-X1; The structural formula of the second styrene-butadiene block copolymer includes: An-X2; wherein A is a styrene butadiene block copolymer, m and n are integers, m≥3, n≥2, X1 is a first coupling agent, and X2 is a residue of a second coupling agent, whose functionality is ≥2; The A is prepared by reacting styrene, butadiene and an initiator, and the first coupling agent is divinylbenzene.

2. The transparent styrene-butadiene impact-resistant resin for cast extrusion sheets according to claim 1, characterized in that: In the first styrene-butadiene block copolymer and the second styrene-butadiene block copolymer, the mass percentage of the structural unit of styrene is 60% to 75%, and the mass percentage of the structural unit of butadiene is 25% to 40%; The structural formula of the first styrene-butadiene block copolymer includes: (St1-L1-Bd1-L2-Bd2 / St2-Bd3)-DVB, wherein St1 is a polystyrene segment, Bd1 and Bd3 are polybutadiene segments, and Bd2 / St2 are segments of random blocks of butadiene and styrene; The second coupling agent includes dimethyldichlorosilane or silicon tetrachloride; the structural formula of the second butadiene-styrene block copolymer includes: (St1-L1-Bd1-L2-Bd2 / St2-Bd3)n-X2, wherein St1 is a polystyrene segment, Bd1 and Bd3 are polybutadiene segments, and Bd2 / St2 is a segment of random blocks of butadiene and styrene.

3. The transparent butadiene-styrene impact-resistant resin for cast extrusion sheets according to claim 1, characterized in that: The number average molecular weight of the first butadiene styrene block copolymer and the second butadiene styrene block copolymer is 30,000 to 200,000 g / mol.

4. The transparent styrene-butadiene impact-resistant resin for cast extrusion sheets according to any one of claims 1 to 3, characterized in that: The styrene-butadiene resin composition also includes an antioxidant, a lubricant, and an anti-aging agent; the lubricant includes microcrystalline wax and / or zinc stearate.

5. A method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets as claimed in any one of claims 1 to 4, characterized in that: The preparation method comprises the following steps: (1) mixing styrene, butadiene and an initiator, and reacting them to obtain a styrene butadiene block copolymer; (2) mixing the styrene butadiene block copolymer obtained in step (1), the first coupling agent and the second coupling agent, reacting them, and adding a terminator to obtain the styrene butadiene resin composition.

6. The method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets according to claim 5, characterized in that: The step (1) comprises the following steps: (S1) mixing a solvent, a regulator, a portion of styrene and a portion of an initiator, and reacting them to obtain a product a; (S2) mixing the product a obtained in step (S1) with a portion of butadiene, and reacting them to obtain a product b; (S3) mixing the product b obtained in step (S2) with the remaining initiator, part of butadiene and the remaining styrene, and reacting them to obtain a product c; (S4) mixing the product c obtained in step (S3) and the remaining butadiene, and reacting them to obtain a product d; (S5) mixing the product d obtained in step (S4) with the first coupling agent and the second coupling agent to react to obtain the styrene butadiene block copolymer.

7. The method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets according to claim 6, characterized in that: The solvent includes any one of cyclohexane, n-hexane or toluene, or a combination of at least two thereof; The regulator includes any one of tetrahydrofuran, tetramethylethylenediamine or diethanol dimethyl ether or a combination of at least two thereof; The initiator includes n-butyl lithium; the molar amount of the divinylbenzene DVB / the molar amount of the initiator is 0.1 to 20; the molar amount of the second coupling agent / the molar amount of the initiator is 0.05 to 1; Based on the total mass of styrene being 100%, in step (S1), the mass percentage of the styrene in the part is 60 to 80%; Taking the total mass of the initiator as 100%, in step (S1), the mass percentage of the initiator of the part is 20 to 75%; Based on the total mass of styrene being 100%, in step (S3), the mass percentage of the styrene in the part is 20 to 40%; Based on the total mass of butadiene being 100%, in step (S2), the mass percentage of butadiene in the portion is 10 to 25%; Based on the total mass of butadiene being 100%, in step (S3), the mass percentage of the styrene in the part is 40 to 70%; Based on the total mass of butadiene being 100%, in step (S4), the mass percentage of the butadiene in the portion is 5 to 50%; The reactions of step (S1), step (S2), step (S3) and step (S4) are each independently carried out to a conversion rate of ≥ 99%; In step (S1), step (S2), step (S3), step (S4) and step (S5), the reaction temperature is independently 40 to 95° C.; In step (S1), step (S2), step (S3), step (S4) and step (S5), the reaction time is independently 20 min to 40 min.

8. The method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets according to claim 5, characterized in that: The terminator includes any one of methanol, isopropanol or water, or a combination of at least two of them.

9. The method for preparing a transparent butadiene-styrene impact-resistant resin for cast extrusion sheets according to claim 5, characterized in that: The method further comprises adding an auxiliary agent into the system after adding the terminator.

10. Use of the styrene-butadiene resin composition according to any one of claims 1 to 4 in impact-resistant products.

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