Preparation methods of MBS resin and MBS resin with improved weather resistance and impact resistance

Abstract

This invention belongs to the technical field of MBS resin preparation, specifically relating to MBS resin and a method for preparing MBS resin with improved weather resistance and impact resistance. The MBS resin of this invention comprises a core layer and a shell layer. The core layer is a butadiene-styrene rubber core, and the shell layer is a copolymer of methyl methacrylate and a weather-resistant functional agent. The raw material composition includes: butadiene, styrene, methyl methacrylate, the weather-resistant functional agent, a seed emulsifier, a graft emulsifier, an initiator, and a molecular weight regulator. The weather-resistant functional agent is a mixture of hydroxyethyl methacrylate, 1,3,5-triacryloyl-1,3,5-triazine, and isobornyl acrylate. The method for preparing MBS resin with improved weather resistance and impact resistance provided by this invention is simple, controllable, and easy for industrial production. The MBS resin prepared by this invention meets the requirements for outdoor high-temperature exposure and exhibits strong impact resistance.

Description

Technical Field

[0001] This invention belongs to the field of MBS resin preparation technology, specifically relating to MBS resin and a method for preparing MBS resin with improved weather resistance and impact resistance. Background Technology

[0002] MBS resin (methyl methacrylate-butadiene-styrene terpolymer), as a key core-shell structured polymer material, has become an indispensable component in transparent PVC products due to its excellent compatibility with matrix resins such as PVC in its shell layer, good transparency, and the outstanding energy absorption capacity of its core rubber phase. It is widely used in packaging, building materials, and optical devices. With the continuous expansion of outdoor applications, such as outdoor transparent sunshades and open-air fences, the market has placed higher demands on the comprehensive performance of MBS resin under harsh environments such as long-term high temperatures and ultraviolet radiation. However, the insufficient weather resistance of traditional MBS resin has become a core bottleneck restricting its high-end outdoor applications.

[0003] Under the combined effects of high outdoor temperatures and ultraviolet radiation, the molecular structure of traditional MBS resin is prone to oxidative degradation. This process directly leads to severe aging in modified products: on the one hand, the color of the products darkens significantly, with a rapid increase in the yellowing index, severely affecting the appearance quality; on the other hand, the material's toughness decreases, and the impact strength is greatly reduced, causing the products to become brittle and shorten their service life. Industry data shows that after several months of outdoor exposure, transparent PVC products modified with traditional MBS resin can have a yellowing index exceeding 15 and an impact strength decrease of more than 30%. Meanwhile, ideal transparent materials for outdoor use not only require high initial light transmittance but also the ability to maintain low haze and stable high light transmittance during aging, but traditional MBS resin often fails to meet these requirements.

[0004] To address these issues, the industry has proposed a method of physically blending various small-molecule additives (such as antioxidants and UV absorbers). While this method can improve weather resistance in the short term, the compatibility of these small-molecule additives with the resin matrix is ​​limited, leading to migration and precipitation during processing and use. This not only causes the weather resistance to rapidly decline with time and environmental exposure, but more seriously, the precipitated additives can form crystals or haze on the surface of the product, resulting in decreased light transmittance and a significant increase in haze, thus damaging the material's most valuable property: transparency.

[0005] Another technique involves introducing other monomers through copolymerization or crosslinking the rubber core to improve stability at the molecular structure level. For example, introducing acrylonitrile monomers into the shell layer attempts to enhance its resistance to photo-oxidation. However, the effect of such chemical modification is limited, providing insufficient improvement in anti-yellowing at high temperatures and potentially weakening interfacial compatibility with the PVC matrix, thus negatively impacting the material's impact resistance. On the other hand, while crosslinking the butadiene rubber core can improve its structural stability, excessive crosslinking severely sacrifices the elasticity of the rubber phase, directly leading to a significant decrease in the core function of MBS resin as an impact modifier—toughening effect. Impact strength may decrease by 20% to 30%, which contradicts the requirements for mechanical durability in outdoor applications. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the above-mentioned defects of the prior art and provide a method for preparing MBS resin with improved weather resistance and impact resistance. The process is simple and controllable and easy to industrialize. The MBS resin prepared by the present invention meets the requirements of outdoor high temperature exposure and has strong impact resistance.

[0007] The MBS resin of this invention comprises a core layer and a shell layer. The core layer is a butadiene-styrene rubber core, and the shell layer is a copolymer of methyl methacrylate and a weather-resistant functional agent. Based on the total weight of raw materials, the raw material composition includes: 20-40 parts butadiene, 10-20 parts styrene, 30-50 parts methyl methacrylate, 5-15 parts weather-resistant functional agent, 0.5-2 parts seed emulsifier, 0.3-1.5 parts graft emulsifier, 0.2-1 part initiator, and 0.1-0.8 parts molecular weight regulator.

[0008] The weather-resistant functional component is a mixture of 1-3 parts of hydroxyethyl methacrylate, 2-4 parts of 1,3,5-triacryloyl-1,3,5-triazine, and 8-12 parts of isoborneol acrylate.

[0009] The seed emulsifier is a compound of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether, with a weight ratio of 1:0.5~2.

[0010] The grafting emulsifier is sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether, the initiator is one or a mixture of two of ammonium persulfate and benzoyl peroxide, and the molecular weight regulator is one or a mixture of two of dodecyl mercaptan and tert-dodecyl mercaptan.

[0011] The raw materials also include, by weight, 100-200 parts of water, preferably deionized water. All the weight percentages mentioned above are based on the entire system of the MBS resin core and shell layers.

[0012] The method for preparing the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0013] S1: Preparation of butadiene-styrene rubber core emulsion: Water and seed emulsifier are added to the reaction vessel, the temperature is raised to 60~70℃, butadiene, styrene, part of the initiator and part of the molecular weight regulator are added, and the reaction is carried out to obtain butadiene-styrene rubber core emulsion;

[0014] S2: Grafted polymerized core-shell MBS emulsion: Cool the rubber core emulsion obtained in step S1 to 50~60℃, add graft emulsifier, then add methyl methacrylate and weather-resistant functional body dropwise, and simultaneously add the remaining initiator and remaining molecular weight regulator. After the addition is completed, raise the temperature to 65~75℃ and keep the reaction at the temperature to obtain the core-shell MBS emulsion.

[0015] S3: Post-treatment: Cool the core-shell MBS emulsion obtained in step S2 to room temperature, adjust the pH to 2-3, allow it to stand and separate into layers, collect the precipitate, wash and dry it to obtain MBS resin with improved weather resistance and impact resistance.

[0016] In S1, the amount of initiator added is 30-50% of the total initiator weight, and the amount of molecular weight regulator added is 40-60% of the total molecular weight regulator weight.

[0017] After adding butadiene, styrene, some initiator and some molecular weight regulator to S1, the mixture is stirred at 200~300 r / min for 4~6 h.

[0018] The remaining initiator and molecular weight regulator in S2 are added dropwise over a period of 2 to 4 hours. After the addition is complete, the temperature is raised to 65 to 75°C and the reaction is maintained at this temperature for 3 to 5 hours.

[0019] While adding the remaining initiator and molecular weight regulator in S2, stir at a speed of 300-400 r / min.

[0020] In S3, the pH is adjusted using hydrochloric acid with a mass fraction of 5-10%, washing is done with deionized water, and drying is carried out at 60-80℃ and a vacuum degree of -0.08--0.1MPa for 8-12 hours.

[0021] Specifically, the preparation method of the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0022] S1: Preparation of butadiene-styrene rubber core emulsion: Deionized water and seed emulsifier are added to the reaction vessel, the temperature is raised to 60~70℃, nitrogen is introduced to replace the air in the vessel 3~5 times, then butadiene, styrene, part of the initiator and molecular weight regulator are added, and the reaction is carried out at a constant temperature of 200~300r / min for 4~6h to obtain butadiene-styrene rubber core emulsion;

[0023] S2: Grafted polymerized core-shell MBS emulsion: Cool the rubber core emulsion obtained in step S1 to 50~60℃, add graft emulsifier, stir evenly, then add methyl methacrylate and weather-resistant functional body dropwise, stir at 300~400r / min, and simultaneously add the remaining initiator and remaining molecular weight regulator dropwise for 2~4h. After the dropwise addition is complete, raise the temperature to 65~75℃ and keep the reaction at this temperature for 3~5h to obtain the core-shell MBS emulsion;

[0024] S3: Post-treatment: Cool the core-shell MBS emulsion obtained in step S2 to room temperature, adjust the pH to 2-3 with 5-10% hydrochloric acid, allow it to stand and separate into layers, collect the precipitate, wash it with deionized water until neutral, and then vacuum dry it at 60-80℃ and -0.08--0.1MPa for 8-12 hours to obtain MBS resin with improved weather resistance and impact resistance.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] (1) The present invention uses specific compounded weather-resistant functional components to participate in copolymerization, which significantly improves the resin’s resistance to ultraviolet radiation and yellowing from the molecular structure, and avoids the migration and precipitation of small molecule additives, thus maintaining high light transmittance and low haze for a long time.

[0027] (2) While enhancing weather resistance, the present invention optimizes the monomer structure and polymerization process to maintain good elasticity of the rubber core, thereby achieving a synergistic improvement in weather resistance and impact resistance.

[0028] (3) The preparation process of this invention is simple and controllable. It adopts stepwise emulsion polymerization and mild post-treatment, resulting in high product purity and easy industrial production. Detailed Implementation

[0029] The present invention will be further described below with reference to specific embodiments.

[0030] All raw materials and additives used below are commercially available products, unless otherwise specified.

[0031] Isoborneol acrylate: Aladdin Reagent (Shanghai) Co., Ltd.

[0032] Sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether: Maclean's reagent.

[0033] Sodium dodecylbenzenesulfonate: Aladdin Reagent (Shanghai) Co., Ltd.

[0034] Fatty alcohol polyoxyethylene ether: Aladdin Reagent (Shanghai) Co., Ltd.

[0035] 1,3,5-Triacryloyl-1,3,5-triazine: Guangdong Yuanfeng Chemical Reagent Co., Ltd.

[0036] Hydroxyethyl methacrylate: Aladdin Reagent (Shanghai) Co., Ltd.

[0037] Example 1

[0038] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 2 parts hydroxyethyl methacrylate, 3 parts 1,3,5-triacryloyl-1,3,5-triazine, 10 parts isobornyl acrylate, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a weight ratio of 1:1), 0.8 parts graft emulsifier (sodium α-sulfo-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water.

[0039] The method for preparing the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0040] S1: Preparation of butadiene-styrene rubber core emulsion: 150 parts of deionized water and 1.2 parts of seed emulsifier were added to the reaction vessel, the temperature was raised to 65℃, nitrogen gas was introduced to replace the air in the vessel 4 times, and then 30 parts of butadiene, 15 parts of styrene, 0.24 parts of initiator and 0.16 parts of molecular weight regulator were added. The reaction was carried out at a constant temperature and stirred for 5 hours at a stirring speed of 250 r / min to obtain the rubber core emulsion.

[0041] S2: Grafted polymerized core-shell emulsion: The rubber core emulsion obtained in step S1 was cooled to 55°C, and 0.8 parts of graft emulsifier were added. After stirring evenly, 40 parts of methyl methacrylate, 2 parts of hydroxyethyl methacrylate, 3 parts of 1,3,5-triacryloyl-1,3,5-triazine, and 10 parts of isobornyl acrylate were added dropwise. At the same time, the remaining 0.36 parts of initiator and the remaining 0.24 parts of molecular weight regulator were added dropwise. The dropwise addition time was 3 hours, and the stirring speed during the dropwise addition was 350 r / min. After the dropwise addition was completed, the temperature was raised to 70°C and the reaction was maintained for 4 hours to obtain a core-shell structured MBS emulsion.

[0042] S3: Post-treatment: Cool the MBS emulsion obtained in step S2 to room temperature, adjust the pH to 2.5 with 8% hydrochloric acid, allow it to stand and separate into layers, collect the precipitate, wash it with deionized water until neutral, and then vacuum dry it for 10 hours at 70℃ and a vacuum degree of -0.09MPa. After pulverizing, a high weather-resistant MBS resin is obtained.

[0043] Example 2

[0044] The MBS resin, by weight, comprises the following raw materials: 40 parts butadiene, 20 parts styrene, 50 parts methyl methacrylate, 2 parts hydroxyethyl methacrylate, 3 parts 1,3,5-triacryloyl-1,3,5-triazine, 10 parts isobornyl acrylate, 2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a weight ratio of 1:2), 1.5 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 1 part initiator (ammonium persulfate), 0.8 parts molecular weight regulator (tert-dodecyl mercaptan), and 200 parts deionized water.

[0045] The method for preparing the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0046] S1: Preparation of butadiene-styrene rubber core emulsion: 200 parts of deionized water and 2 parts of seed emulsifier were added to the reaction vessel, heated to 70°C, and nitrogen gas was introduced to replace the air in the vessel 5 times. Then, 40 parts of butadiene, 20 parts of styrene, 0.5 parts of initiator and 0.48 parts of molecular weight regulator were added, and the reaction was carried out at a constant temperature and stirred for 6 hours at a stirring speed of 300 r / min to obtain the rubber core emulsion.

[0047] S2: Grafted polymerized core-shell MBS emulsion: The rubber core emulsion obtained in step S1 was cooled to 60℃, 1.5 parts of graft emulsifier were added, and after stirring evenly, 50 parts of methyl methacrylate, 2 parts of hydroxyethyl methacrylate, 3 parts of 1,3,5-triacryloyl-1,3,5-triazine, and 10 parts of isobornyl acrylate were added dropwise. At the same time, the remaining 0.5 parts of initiator and the remaining 0.32 parts of molecular weight regulator were added dropwise. The dropwise addition time was 4h, and the stirring speed during the dropwise addition was 400r / min. After the dropwise addition was completed, the temperature was raised to 75℃ and the reaction was maintained for 5h to obtain a core-shell MBS emulsion.

[0048] S3: Post-treatment: Cool the MBS emulsion obtained in step S2 to room temperature, adjust the pH to 3 with 10% hydrochloric acid, allow it to stand and separate into layers, collect the precipitate, wash it with deionized water until neutral, and then vacuum dry it for 12 hours at 80℃ and a vacuum degree of -0.1MPa. After pulverizing, high weather-resistant MBS resin is obtained.

[0049] Example 3

[0050] The MBS resin, by weight, comprises the following raw materials: 25 parts butadiene, 12 parts styrene, 35 parts methyl methacrylate, 2 parts hydroxyethyl methacrylate, 3 parts 1,3,5-triacryloyl-1,3,5-triazine, 10 parts isobornyl acrylate, 0.8 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a weight ratio of 1:0.8), 0.5 parts graft emulsifier (sodium α-sulfo-ω-nonylphenoxy polyoxyethylene ether), 0.4 parts initiator (ammonium persulfate and benzoyl peroxide in a weight ratio of 1:1), 0.3 parts molecular weight regulator (dodecyl mercaptan and tert-dodecyl mercaptan in a weight ratio of 1:1), and 120 parts deionized water.

[0051] The method for preparing the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0052] S1: Preparation of butadiene-styrene rubber core emulsion: 120 parts of deionized water and 0.8 parts of seed emulsifier were added to the reaction vessel, the temperature was raised to 62℃, nitrogen gas was introduced to replace the air in the vessel 3 times, and then 25 parts of butadiene, 12 parts of styrene, 0.16 parts of initiator and 0.12 parts of molecular weight regulator were added. The reaction was carried out at a constant temperature and stirred for 4.5 h at a stirring speed of 220 r / min to obtain the rubber core emulsion.

[0053] S2: Grafted Polymerized Core-Shell MBS Emulsion: The rubber core emulsion obtained in step S1 was cooled to 52℃, and 0.5 parts of graft emulsifier were added. After stirring evenly, 35 parts of methyl methacrylate, 2 parts of hydroxyethyl methacrylate, 3 parts of 1,3,5-triacryloyl-1,3,5-triazine, and 10 parts of isobornyl acrylate were added dropwise. Simultaneously, the remaining 0.24 parts of initiator and the remaining 0.18 parts of molecular weight regulator were added dropwise over a period of 2.5 hours, with a stirring speed of 320 r / min. After the addition was complete, the temperature was raised to 68℃ and the reaction was maintained for 3.5 hours to obtain a core-shell MBS emulsion.

[0054] S3: Post-treatment: Cool the MBS emulsion obtained in step S2 to room temperature, adjust the pH to 2.2 with 6% hydrochloric acid, allow it to stand and separate into layers, collect the precipitate, wash it with deionized water until neutral, and then vacuum dry it at 65℃ and a vacuum degree of -0.085MPa for 9 hours. After pulverizing, a high weather-resistant MBS resin is obtained.

[0055] Example 4

[0056] The MBS resin, by weight, comprises the following raw materials: 35 parts butadiene, 18 parts styrene, 45 parts methyl methacrylate, 2 parts hydroxyethyl methacrylate, 3 parts 1,3,5-triacryloyl-1,3,5-triazine, 10 parts isobornyl acrylate, 1.5 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a weight ratio of 1:1.5), 1.2 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.8 parts initiator (benzoyl peroxide), 0.6 parts molecular weight regulator (tert-dodecyl mercaptan), and 180 parts deionized water.

[0057] The method for preparing the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0058] S1: Preparation of butadiene-styrene rubber core emulsion: 180 parts of deionized water and 1.5 parts of seed emulsifier were added to the reaction vessel, the temperature was raised to 68℃, nitrogen gas was introduced to replace the air in the vessel 5 times, and then 35 parts of butadiene, 18 parts of styrene, 0.32 parts of initiator and 0.24 parts of molecular weight regulator were added. The reaction was carried out at a constant temperature and stirred for 5.5 h at a stirring speed of 280 r / min to obtain the rubber core emulsion.

[0059] S2: Grafted polymerized core-shell MBS emulsion: The rubber core emulsion obtained in step S1 was cooled to 58℃, 1.2 parts of graft emulsifier were added, and after stirring evenly, 45 parts of methyl methacrylate, 2 parts of hydroxyethyl methacrylate, 3 parts of 1,3,5-triacryloyl-1,3,5-triazine, and 10 parts of isobornyl acrylate were added dropwise. At the same time, the remaining 0.48 parts of initiator and the remaining 0.36 parts of molecular weight regulator were added dropwise. The dropwise addition time was 3.5h, and the stirring speed during the dropwise addition was 380r / min. After the dropwise addition was completed, the temperature was raised to 72℃ and the reaction was maintained for 4.5h to obtain a core-shell MBS emulsion.

[0060] S3: Post-treatment: Cool the MBS emulsion obtained in step S2 to room temperature, adjust the pH value to 2.8 with 9% hydrochloric acid, allow it to stand and separate into layers, collect the precipitate, wash it with deionized water until neutral, and then vacuum dry it for 11 hours at 75℃ and a vacuum degree of -0.095MPa. After pulverizing, a high weather-resistant MBS resin is obtained.

[0061] Example 5

[0062] The MBS resin, by weight, comprises the following raw materials: 32 parts butadiene, 16 parts styrene, 42 parts methyl methacrylate, 3 parts hydroxyethyl methacrylate, 4 parts 1,3,5-triacryloyl-1,3,5-triazine, 8 parts isobornyl acrylate, 1.7 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a weight ratio of 1:1.8), 1.0 part graft emulsifier (sodium α-sulfo-ω-nonylphenoxy polyoxyethylene ether), 0.7 parts initiator (ammonium persulfate), 0.5 parts molecular weight regulator (dodecyl mercaptan), and 160 parts deionized water.

[0063] The method for preparing the MBS resin with improved weather resistance and impact resistance includes the following steps:

[0064] S1: Preparation of butadiene-styrene rubber core emulsion: 160 parts of deionized water and 1.7 parts of seed emulsifier were added to the reaction vessel, the temperature was raised to 66℃, nitrogen gas was introduced to replace the air in the vessel 4 times, and then 32 parts of butadiene, 16 parts of styrene, 0.28 parts of initiator and 0.25 parts of molecular weight regulator were added. The reaction was carried out at a constant temperature and stirred for 5.2 h at a stirring speed of 260 r / min to obtain the rubber core emulsion.

[0065] S2: Grafted polymerized core-shell MBS emulsion: The rubber core emulsion obtained in step S1 was cooled to 56℃, 1.0 part of graft emulsifier was added, and after stirring evenly, 42 parts of methyl methacrylate, 3 parts of hydroxyethyl methacrylate, 4 parts of 1,3,5-triacryloyl-1,3,5-triazine, and 12 parts of isobornyl acrylate were added dropwise. At the same time, the remaining 0.42 parts of initiator and the remaining 0.25 parts of molecular weight regulator were added dropwise. The dropwise addition time was 3.2h, and the stirring speed during the dropwise addition was 360r / min. After the dropwise addition was completed, the temperature was raised to 71℃ and the reaction was maintained for 4.2h to obtain a core-shell MBS emulsion.

[0066] S3: Post-treatment: Cool the MBS emulsion obtained in step S2 to room temperature, adjust the pH value to 2.6 with 7% hydrochloric acid, allow it to stand and separate into layers, collect the precipitate, wash it with deionized water until neutral, and then vacuum dry it for 10.5 h at 68℃ and a vacuum degree of -0.092 MPa. After pulverizing, a high weather-resistant MBS resin is obtained.

[0067] Comparative Example 1

[0068] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a weight ratio of 1:1), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water.

[0069] The preparation method is the same as in Example 1, except that no weather-resistant functional ingredients are added.

[0070] Comparative Example 2

[0071] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 15 parts hydroxyethyl methacrylate, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a 1:1 weight ratio), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water. The weather-resistant functional body is prepared by adding only hydroxyethyl methacrylate; the remaining steps are the same as in Example 1.

[0072] Comparative Example 3

[0073] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 15 parts 1,3,5-triacryloyl-1,3,5-triazine, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a 1:1 weight ratio), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water. The weather-resistant functional body is prepared by adding only 1,3,5-triacryloyl-1,3,5-triazine; the remaining steps are the same as in Example 1.

[0074] Comparative Example 4

[0075] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 15 parts isoborneol acrylate, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a 1:1 weight ratio), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water. The weather-resistant functional body is prepared by adding only isoborneol acrylate; the remaining steps are the same as in Example 1.

[0076] Comparative Example 5

[0077] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 7 parts hydroxyethyl methacrylate, 8 parts isoborneol acrylate, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a 1:1 weight ratio), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water. The weather-resistant functional body is prepared by adding only hydroxyethyl methacrylate and isoborneol acrylate; the remaining steps are the same as in Example 1.

[0078] Comparative Example 6

[0079] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 2 parts hydroxyethyl methacrylate, 3 parts 1,3,5-triacryloyl-1,3,5-triazine, 10 parts isobornyl acrylate, 1.2 parts seed emulsifier (sodium dodecylbenzenesulfonate), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water. The seed emulsifier in the preparation method only adds sodium dodecylbenzenesulfonate; the remaining steps are the same as in Example 1.

[0080] Comparative Example 7

[0081] The MBS resin, by weight, comprises the following raw materials: 30 parts butadiene, 15 parts styrene, 40 parts methyl methacrylate, 2 parts hydroxyethyl methacrylate, 3 parts 1,3,5-triacryloyl-1,3,5-triazine, 10 parts isobornyl acrylate, 1.2 parts seed emulsifier (fatty alcohol polyoxyethylene ether), 0.8 parts graft emulsifier (sodium α-sulfonyl-ω-nonylphenoxy polyoxyethylene ether), 0.6 parts initiator (ammonium persulfate), 0.4 parts molecular weight regulator (dodecyl mercaptan), and 150 parts deionized water. The seed emulsifier in the preparation method only adds fatty alcohol polyoxyethylene ether; the remaining steps are the same as in Example 1.

[0082] Comparative Example 8

[0083] The composition of the MBS resin raw materials in this comparative example is exactly the same as that in Example 1, but the specific steps of the preparation method are as follows:

[0084] S1: Add 150 parts of deionized water and 1.2 parts of seed emulsifier to the reactor, heat to 55°C, purge the air in the reactor with nitrogen four times, then add 30 parts of butadiene, 15 parts of styrene, 0.6 parts of initiator and 0.4 parts of molecular weight regulator, followed by the addition of 40 parts of methyl methacrylate, 2 parts of hydroxyethyl methacrylate, 3 parts of 1,3,5-triacryloyl-1,3,5-triazine and 10 parts of isobornyl acrylate. Stir at 350 r / min, heat to 70°C, maintain the temperature for 4 h, cool to room temperature, adjust the pH to 2.5 with 8% hydrochloric acid, allow to stand and separate into layers, collect the precipitate, wash with deionized water until neutral, then vacuum dry at 70°C and -0.09 MPa for 10 h, and pulverize to obtain high weather-resistant MBS resin.

[0085] Performance Testing: Impact test specimens were prepared from the MBS resins used in the examples and comparative examples. By weight, 100 parts PVC (SG-5), 1 part processing aid (organotin catalyst T-12), 5 parts titanium dioxide (R-105), 15 parts calcium powder (lightweight), 5 parts MBS resin (examples and comparative examples), and 0.2 parts stearic acid 1801 were mixed evenly and placed in a two-roll mill at 180°C for 2 minutes to form sheets. After cutting, the sheets were placed in a flat vulcanizing machine and preheated at 190°C for 2 minutes for vulcanization. The sheets were then cooled to form plates. Five specimens (10mm wide, 8cm long, and 4mm thick) were prepared using a universal milling machine. Notches (8mm wide) were then made using a notch-making machine. The specimens were placed in an 80°C oven for 1 hour to relieve stress, then kept at a constant temperature for 3 hours. Notched impact strength and other tests were performed using a simply supported beam. The test items included impact strength (tested according to GB / T1843-2008), light transmittance and haze (tested according to GB / T2410-2008), and yellowing index (tested according to GB / T2409-2008, artificial accelerated aging conditions: xenon lamp aging for 720 hours). The test results are shown in Table 1 below:

[0086] Table 1 Test Results

[0087]

[0088] As shown in Table 1, this invention incorporates hydroxyethyl methacrylate, 1,3,5-triacryloyl-1,3,5-triazine, and isobornyl acrylate as weather-resistant functional agents into the MBS resin formulation. The combination of these three agents significantly enhances the core properties of weather resistance, impact resistance, and optical performance, surpassing the effects of single or two monomer combinations. Furthermore, the formulated emulsifier precisely controls the rubber core particle size distribution, improving emulsion stability and grafting efficiency, which is superior to single emulsifier systems. This invention employs a two-step process, achieving an ordered structure of the rubber core and shell through stepwise core-shell polymerization, avoiding the structural chaos problems associated with one-step processes.

Claims

1. An MBS resin characterized by: The core layer is a butadiene-styrene rubber core, and the shell layer is a copolymer of methyl methacrylate and a weather-resistant functional body, and the raw materials include, by weight parts of the total raw materials: butadiene 20-40 parts, styrene 10-20 parts, methyl methacrylate 30-50 parts, weather-resistant functional body 5-15 parts, seed emulsifier 0.5-2 parts, grafting emulsifier 0.3-1.5 parts, initiator 0.2-1 part, molecular weight regulator 0.1-0.8 part; The weather-resistant functional body is a mixture of hydroxyethyl methacrylate, 1,3,5-triacryloyl-1,3,5-triazine, and isobornyl acrylate; The seed emulsifier is a compound of sodium dodecyl benzene sulfonate and fatty alcohol polyoxyethylene ether; The preparation method of the MBS resin comprises the following steps: S1: preparing a butadiene-styrene rubber core emulsion: adding water and a seed emulsifier to a reaction container, heating to 60-70℃, adding butadiene, styrene, part of the initiator and part of the molecular weight regulator, and reacting to obtain a butadiene-styrene rubber core emulsion; S2: grafting and polymerizing the core-shell MBS emulsion: cooling the rubber core emulsion obtained in step S1 to 50-60℃, adding a grafting emulsifier, then adding methyl methacrylate and a weather-resistant functional body dropwise, while adding the remaining initiator and the remaining molecular weight regulator, after the dropwise addition is completed, heating to 65-75℃, and reacting to obtain a core-shell MBS emulsion; S3: post-treatment: cooling the core-shell MBS emulsion obtained in step S2 to room temperature, adjusting the pH to 2-3, standing and separating, collecting the precipitate, washing and drying to obtain an MBS resin with improved weather resistance and impact resistance.

2. The MBS resin according to claim 1, characterized in that: The weight ratio of the sodium dodecyl benzene sulfonate to the fatty alcohol polyoxyethylene ether is 1:0.5-2.

3. The MBS resin according to claim 1, characterized in that: The grafting emulsifier is alpha-sulfo-omega-nonyl phenoxy polyoxyethylene ether sodium salt, the initiator is one or a mixture of both of ammonium persulfate and benzoyl peroxide, and the molecular weight regulator is one or a mixture of both of dodecanethiol and tertiary dodecanethiol.

4. The MBS resin according to claim 1, characterized by: The raw materials further include, by weight parts of the total raw materials: water 100-200 parts; and the weather-resistant functional body: a mixture of hydroxyethyl methacrylate 1-3 parts, 1,3,5-triacryloyl-1,3,5-triazine 2-4 parts, and isobornyl acrylate 8-12 parts.

5. The MBS resin according to claim 1, characterized in that: The amount of the part of the initiator added in S1 is 30-50% of the total weight of the initiator, and the amount of the part of the molecular weight regulator added is 40-60% of the total weight of the molecular weight regulator.

6. The MBS resin according to claim 5, characterized in that: After adding butadiene, styrene, the part of the initiator and the part of the molecular weight regulator in S1, the reaction is stirred at 200-300 r / min for 4-6 h.

7. The MBS resin according to claim 1, characterized in that: In S2, the dropwise addition of the remaining initiator and the remaining molecular weight regulator is performed for 2-4 h, after the dropwise addition is completed, the temperature is raised to 65-75℃, and the reaction is maintained for 3-5 h.

8. The MBS resin according to claim 7, characterized by: In S2, the dropwise addition of the remaining initiator and the remaining molecular weight regulator is performed while stirring, and the stirring speed is 300-400 r / min.

9. The MBS resin according to claim 1, characterized in that: In S3, the pH is adjusted by using hydrochloric acid with a mass fraction of 5-10%, the washing is performed by using deionized water, and the drying is performed at 60-80 DEG C under a vacuum degree of-0.08 to-0.1 MPa for 8-12 h.

Images