Hydrolysis-resistant agent, preparation method, hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin and preparation method of hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin

Abstract

The invention discloses a hydrolysis-resistant agent and a preparation method thereof. The hydrolysis-resistant agent is prepared by mixing an RAFT reagent containing macromolecular groups with a vinyl epoxy compound, an initiator and an organic solvent and reacting in a protective gas environment, the hydrolysis-resistant agent is used as the hydrolysis-resistant agent for modifying polybutylene terephthalate resin, and the hydrolysis resistance of the hydrolysis-resistant agent is improved on the basis of keeping the hydrolysis resistance of the hydrolysis-resistant agent. The mobility of the hydrolysis-resistant agent in a material matrix can be greatly improved. The invention also provides a hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin material, by adopting the hydrolysis-resistant agent, the hydrolysis problem in the processing process can be solved, the performance-maintaining low-cost modified PBT material can be simply and efficiently prepared, and the hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin material has a wide application prospect in the fields of automobiles / household appliances / electronic appliances.

Description

Technical Field

[0001] The invention relates to the field of modified thermoplastic resin materials, and more specifically to a hydrolysis resistant agent, a preparation method, and a hydrolysis resistant glass fiber reinforced polybutylene terephthalate resin material and a preparation method. Background Art

[0002] Polybutylene terephthalate resin, referred to as PBT, has shown its irreplaceable superior performance in some industrial applications. It has now become the fifth most common engineering plastic after PA, PC, POM (polyoxymethylene) and MPPO (modified polyphenylene ether).

[0003] PBT is a milky white, translucent to opaque, semi-crystalline thermoplastic polyester with high heat resistance and resistance to organic solvents. However, due to its inability to resist strong acids and alkalis, flammability, and decomposition at high temperatures, pure PBT resin often cannot meet the special application needs in some fields, and relying solely on improved processing cannot solve the problem. Therefore, most PBT resins are processed into compounding materials for use. After being modified with various additives, they can be blended with other resins to obtain good comprehensive properties such as heat resistance, flame retardancy, and electrical insulation, as well as good processing properties. They are widely used in industrial environments such as electrical appliances, automobiles, aircraft manufacturing, communications, home appliances, and transportation.

[0004] However, the PBT resin material modified by the above method will also encounter various difficulties in the actual processing process. Among them, material hydrolysis is the most common and difficult aspect. Because PBT resin contains ester chains, it has a strong tendency to absorb moisture. The water absorption rate is generally 0.2-0.3%. When processed in a hygroscopic state, the material chain segments are heated and the ester chains will hydrolyze, thereby degrading the material.

[0005] There are two main solutions in the market: (1) Drying is required before processing to reduce the moisture content to below 0.02%, with a drying temperature of 110-130°C and a drying time of about 4 hours. This method has a good effect on improving the performance of the final modified PBT material, but its operation convenience and timeliness are poor and it is not suitable for current large-scale production line factories; (2) During the processing of PBT materials, a hydrolysis-resistant agent is added for physical blending. For this method, the type of hydrolysis agent has a greater impact on the final modified PBT material. Monomeric carbodiimide, isocyanate, oxazoline compounds, epoxy and other materials have a low density of reactive groups and have poor improvement in hydrolysis effects. Increasing their number will pose a risk of precipitation. Polymeric compounds can improve this phenomenon, but there are currently fewer types of materials to choose from, and they are basically all polymeric carbodiimide compounds, which will greatly increase material costs.

[0006] Therefore, how to reduce material costs and enrich the types of additives while ensuring the performance and processing efficiency of PBT materials is a challenging direction, and it is also a direction to greatly expand the application field of modified PBT materials. Summary of the invention

[0007] In view of this, one of the purposes of the present invention is to provide a hydrolysis resistant agent and a preparation method thereof, wherein the hydrolysis resistant agent is an epoxy monomer polymer with a macromolecular group at the end group. The present invention adopts a RAFT polymerization method, selects a RAFT agent with a macromolecular end group, and directionally designs a high molecular polymer, and finally obtains a polyepoxy hydrolysis resistant agent material with a macromolecular end group. The hydrolysis resistant agent can be applied to the field of modified PBT resin.

[0008] The second object of the present invention is to provide a hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin and a preparation method thereof. The use of the above-mentioned polyepoxy hydrolysis-resistant agent with macromolecular end groups can solve the hydrolysis problem in the processing process and simply and efficiently obtain a low-cost modified PBT material that maintains performance.

[0009] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0010] In a first aspect, the present invention provides a method for preparing a hydrolysis resistance agent, comprising the following steps:

[0011] The RAFT agent containing a macromolecular group is mixed with a vinyl epoxy compound, an initiator and an organic solvent, and reacted in a protective gas environment to obtain the hydrolysis-resistant agent.

[0012] In one embodiment, the RAFT agent containing a macromolecular group of the present invention, wherein the RAFT agent is a reverse addition-fragmentation chain transfer agent, has a branched chain structure, and includes a thioester compound, wherein the macromolecular group contained is one or more of a group derived from a dithioester, a dithiocarbamate, a xanthate, and a trithiocarbonate, preferably a group derived from a dithioester;

[0013] Preferably, the RAFT agent containing a macromolecular group is one or more of benzyl dithiobenzoate, butyl dithiobenzoate, and isobutyl dithiobenzoate.

[0014] In one embodiment, the vinyl epoxy compound of the present invention is selected from one or more of vinyl methane oxide, vinyl butylene oxide, vinyl ethylene oxide, etc., preferably one or more of vinyl ethylene oxide and vinyl butylene oxide.

[0015] In one embodiment, the organic solvent of the present invention is selected from one or more of furans, alcohols, and halogenated alkane compounds, preferably one or more of tetrahydrofuran (THF), methanol, ethanol, dichloromethane, etc., more preferably one or more of THF and ethanol.

[0016] In one embodiment, the initiator of the present invention is selected from azo compounds, preferably azobisisobutyronitrile (AIBN), azobisisovaleronitrile (AMBN), azobisisoheptanenitrile (ABVN), azobiscyclohexylcarbonitrile (ACCN), more preferably one or more of AIBN and ABVN.

[0017] In one embodiment, the mass ratio of the RAFT agent containing a macromolecular group to the vinyl epoxy compound of the present invention is 1:0.1-1000, which can be 1:0.1, 1:5, 1:10, 1:30, 1:50, 1:70, 1:90, 1:100, 1:120, 1:140, 1:160, 1:180, 1:200, 1:220, 1:240, 1:260, 1:280, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:700, 1:800, 1:900, 1:1000 or a range consisting of any two thereof;

[0018] The mass ratio of the initiator to the vinyl epoxy compound is 1:10-1000, which can be 1:10, 1:50, 1:100, 1:150, 1:200, 1:250, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:650, 1:700, 1:750, 1:800, 1:850, 1:900, 1:950, 1:1000 or a range consisting of any two thereof;

[0019] The amount of the organic solvent is 1-100 times the mass of the vinyl epoxy compound, and can be 1 time, 5 times, 10 times, 15 times, 20 times, 30 times, 40 times, 50 times, 60 times, 70 times, 80 times, 90 times, 100 times or a range consisting of any two thereof.

[0020] In one embodiment, the reaction of the present invention, the temperature is 70-100 ° C, the time is 24-120h, specifically, the temperature can be 70 ° C, 75 ° C, 80 ° C, 85 ° C, 90 ° C, 95 ° C, 100 ° C or a range consisting of any two thereof, the time can be 24h, 30h, 35h, 40h, 45h, 50h, 55h, 60h, 65h, 70h, 75h, 80h, 85h, 90h, 100h, 110h, 120h or a range consisting of any two thereof;

[0021] The reaction is carried out in a protective gas environment. In the present invention, the protective gas refers to a gas that is inert in the reaction, such as nitrogen, argon, etc.;

[0022] Generally, the reaction is carried out under stirring, and the stirring speed can be selected according to actual needs, such as 200-800 rpm / min.

[0023] In one embodiment, after the reaction of the present invention is completed, the method further comprises placing the reaction solution to stand for precipitation treatment, filtering to obtain a precipitate, and drying to obtain the anti-hydrolysis agent;

[0024] Wherein, the precipitation treatment has no special requirements on the temperature, for example, it can be carried out at room temperature, and the precipitation time is 12-72 hours, which can be 12 hours, 15 hours, 20 hours, 25 hours, 30 hours, 35 hours, 40 hours, 45 hours, 50 hours, 55 hours, 60 hours, 65 hours, 70 hours, 72 hours or a range consisting of any two thereof;

[0025] Wherein, the drying is vacuum drying, the drying temperature is 70-100°C, and the drying time is 12-72h. Specifically, the drying temperature can be 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C or a range consisting of any two thereof, and the drying time can be 12h, 15h, 20h, 25h, 30h, 35h, 40h, 45h, 50h, 55h, 60h, 65h, 70h, 72h or a range consisting of any two thereof.

[0026] In a second aspect, the present invention provides a hydrolysis-resistant agent prepared by the above method.

[0027] Specifically, the anti-hydrolysis agent is an epoxy monomer polymer with a macromolecular group at the end, and the molecular weight is 10000-100000, which can be 10000, 20000, 30000, 40000, 50000, 60000, 70000, 80000, 90000, 100000 or a range consisting of any two thereof.

[0028] In a third aspect, the present invention provides a use of the anti-hydrolysis agent described above.

[0029] The anti-hydrolysis agent of the present invention has the advantages of low cost, precipitation resistance and the like, and can be used in the fields of thermoplastic modified plastic processing and the like, and is particularly suitable for preparing modified PBT, TPU, PLA and the like.

[0030] In a fourth aspect, the present invention provides a hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin, which comprises the hydrolysis-resistant agent described above in the present invention, and is specifically prepared from components comprising the following mass percentages:

[0031] Polybutylene terephthalate resin 35-90%,

[0032] Glass fiber 10-50%,

[0033] Toughener 3-20%,

[0034] Lubricant 0.1-1%,

[0035] Antioxidant 0.1-2%,

[0036] Hydrolysis resistant agent 0.1-5%,

[0037] Masterbatch 1-5%.

[0038] Specifically, the glass fiber reinforced polybutylene terephthalate resin is prepared from the following components in percentage by weight:

[0039] The polybutylene terephthalate resin may be 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% or a range consisting of any two thereof;

[0040] The glass fiber may be 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% or a range consisting of any two thereof;

[0041] The toughening agent may be 3%, 5%, 7%, 9%, 10%, 12%, 14%, 16%, 18%, 20% or a range consisting of any two thereof;

[0042] The lubricant may be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1% or a range consisting of any two thereof;

[0043] The antioxidant may be 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.2%, 1.4%, 1.6%, 1.8%, 2% or a range consisting of any two thereof;

[0044] The anti-hydrolysis agent may be 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5% or a range consisting of any two thereof;

[0045] The masterbatch may be 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5% or a range consisting of any two thereof.

[0046] In one embodiment, the polybutylene terephthalate resin has a melt flow index at 250°C and 2.16 kg of 5-60 g / min, which may be 5 g / min, 10 g / min, 20 g / min, 30 g / min, 40 g / min, 50 g / min, 60 g / min, or a range consisting of any two thereof, specifically tested in accordance with ISO 1133 standard.

[0047] In one embodiment, the glass fiber is an alkali-free chopped glass fiber; preferably, the fiber diameter is 10-15um, and the fiber length is 1-5mm. Specifically, the fiber diameter can be 10um, 11um, 12um, 13um, 14um, 15um, or a range between any two thereof, and the fiber length can be 1mm, 2mm, 3mm, 4mm, 5mm, or a range between any two thereof;

[0048] Preferably, the glass fiber is one or more of ECS13-4.5-T438H, ECS13-4.5-T438R, and TLD-CS-T436S.

[0049] In one embodiment, the anti-hydrolysis agent is the anti-hydrolysis agent described above in the present invention, and may also include an existing known anti-hydrolysis agent, such as being mixed with one or more of ADR4468 and S9000, with the mixing ratio not exceeding 50wt%.

[0050] The raw materials of the resin of the present invention also include conventional additives in the fields of toughening agents, lubricants, antioxidants, anti-light agents, masterbatches, etc. In some specific examples, the following raw material selections can be used:

[0051] The toughening agent is selected from one or more of polyolefin elastomer, EPDM rubber, ethylene-acrylate, glycidyl methacrylate, etc., preferably one or more of random terpolymers of ethylene-acrylate and glycidyl methacrylate (such as AX8900, PTW), etc.;

[0052] The lubricant is one or more of pentaerythritol stearate (PETS), zinc stearate (ZNST), polyethylene wax, etc.;

[0053] The antioxidant is one or more of SUNSHOW 1010, SUNSHOW 168, SUNSHOW 5585, etc.;

[0054] The masterbatch is one or more of UN6269, XP6621A, 3600 and the like.

[0055] In a fifth aspect, the present invention also provides a method for preparing the hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin, which can be prepared by conventional modification methods in the art, and the specific operations and parameters can be selected according to actual conditions, and the present invention has no special requirements;

[0056] Specifically, a method for preparing a hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin comprises the following steps:

[0057] The raw materials except glass fiber are mixed and added to the main feeding port of the twin-screw extruder, and the glass fiber is added to the side feeding port, and extruded into granules to obtain hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin.

[0058] Wherein, the twin-screw extruder has a temperature setting of 220-245°C and a screw speed of 200-500 rpm. Specifically, the temperature may be 220°C, 225°C, 230°C, 235°C, 240°C, 245°C or a range consisting of any two thereof, and the screw speed may be 200 rpm, 300 rpm, 400 rpm, 500 rpm or a range consisting of any two thereof.

[0059] Wherein, in the extrusion granulation, the cooling water temperature is 10-50°C, and the pelletizer speed is 10-100 rpm. Specifically, the temperature can be 10°C, 20°C, 30°C, 40°C, 50°C or a range between any two thereof, and the screw speed can be 10 rpm, 30 rpm, 50 rpm, 70 rpm, 90 rpm, 100 rpm or a range between any two thereof.

[0060] In the above method, the raw materials entering the main feeding port are mixed by a high-speed mixer until they are uniformly dispersed; and all the raw materials do not require pre-processing and can be used directly under the premise of keeping them dry.

[0061] Compared with the prior art, the advantages of the technical solution of the present invention are:

[0062] The present invention utilizes RAFT active polymerization design to obtain an epoxy monomer polymer with a macromolecular group at the end group for use as a hydrolysis resistant agent, and utilizes the "fixing effect" of the macromolecular end group to limit the migration effect of the hydrolysis resistant agent in the matrix resin, thereby improving the disadvantage of its easy precipitation. The use of the polymer for modifying PBT materials can solve the hydrolysis problem in the processing process, and obtain a hydrolysis resistant glass fiber reinforced polybutylene terephthalate resin material with simple processing and controllable cost. DETAILED DESCRIPTION

[0063] The following examples will further illustrate the method provided by the present invention, but the present invention is not limited to the listed examples, and should also include any other known changes within the scope of the rights claimed by the present invention.

[0064] Unless otherwise specified, the reagents, materials and instruments used in the following examples are conventional reagents, conventional materials and conventional instruments in the art and can be obtained commercially. The reagents involved can also be synthesized by conventional methods in the art.

[0065] Preparation example of hydrolysis resistant agent:

[0066] The sources of the main raw materials used in the preparation process are as follows:

[0067] THF: Shanghai MacLean Biochemical Technology Co., Ltd.;

[0068] 2-vinyl oxirane monomer: Shanghai Jixiang Biotechnology Co., Ltd.;

[0069] 2-vinyl butane oxide monomer: Shanghai Jixiang Biotechnology Co., Ltd.;

[0070] Macromolecular end group RAFT agents: benzyl dithiobenzoate, butyl dithiobenzoate, Hubei Jianchu Biopharmaceutical Company;

[0071] Initiator Monomer: AIBN: Aladdin.

[0072] Preparation Example 1 (hydrolysis resistant agent S-1):

[0073] 1000gTHF solvent was added to a round-bottom flask, and then 4g of RAFT agent benzyl dithiobenzoate was added. After stirring for 20min, the RAFT agent was completely dissolved, and then 1g of initiator monomer AIBN and 500g of 2-vinyl oxirane monomer were added to react. During the reaction, argon was continuously introduced for deoxygenation. The reaction conditions were 70°C, the stirring speed was 250rpm / min, and the reaction time was 72h. The product was then allowed to stand for 72h to precipitate, and then filtered to obtain a precipitate. The precipitate was dried in a vacuum oven at 100°C for 24h to finally obtain a hydrolysis-resistant agent S-1 with a molecular weight of approximately 19267.

[0074] Preparation Example 2 (hydrolysis resistant agent S-2):

[0075] 10000g of ethanol solvent was added to a round-bottom flask, and then 4g of RAFT agent butyl dithiobenzoate was added. After stirring for 20min, the RAFT agent was completely dissolved, and then 1g of initiator monomer ABVN was added, and then 1000g of 2-vinyl butylene oxide monomer was added to react. Nitrogen was continuously introduced during the reaction for deoxygenation. The reaction conditions were 70°C, the stirring speed was 8000rpm / min, and the reaction time was 36h. The product was then allowed to stand for 72h to precipitate, and then filtered to obtain a precipitate. The precipitate was dried in a vacuum oven at 100°C for 24h to finally obtain a hydrolysis-resistant agent S-2 with a molecular weight of approximately 37568.

[0076] Preparation Example 3 (hydrolysis resistant agent S-3):

[0077] 10000g THF solvent was added to a round-bottom flask, and then 10g RAFT agent benzyl dithiobenzoate was added. After stirring for 20 minutes, the RAFT agent was completely dissolved, and then 1g initiator monomer ABVN and 100g 2-vinyl oxirane monomer were added to react. Nitrogen was continuously introduced during the reaction for deoxygenation. The reaction conditions were 90°C, the stirring speed was 200rpm / min, and the reaction time was 24h. The product was then allowed to stand for 72h to precipitate, and then filtered to obtain a precipitate. The precipitate was dried in a vacuum oven at 100°C for 24h to finally obtain a hydrolysis-resistant agent S-3 with a molecular weight of approximately 10798.

[0078] Below, the above-mentioned hydrolysis resistant agent is provided for preparing an example of a hydrolysis resistant glass fiber reinforced polybutylene terephthalate resin.

[0079] Example 1

[0080] The main raw materials used in the preparation process of this embodiment are as follows:

[0081] The polybutylene terephthalate resin is 1100-211S with a melt flow index of 12 g / min. The test conditions are in accordance with ISO 1133 standard: 250°C, 2.16 kg. It is produced by Changchun Chemical (Jiangsu) Co., Ltd.

[0082] The glass fiber is ECS13-4.5-T438H, produced by Taishan Fiberglass, with a fiber diameter of 13um and a fiber length of 4.5mm;

[0083] The toughening agent is a random terpolymer of glycidyl methacrylate, with the brand name PTW, produced by DuPont;

[0084] The lubricant was zinc stearate (ZnST), produced by Faji Co., Ltd.

[0085] The antioxidants were SUNSHOW 168 and SUNSHOW 1010, produced by Xinxiu Chemical Co., Ltd.

[0086] The masterbatch is XP6621A, produced by Cabot Co., Ltd.

[0087] The anti-hydrolysis agent is the anti-hydrolysis agent S-1 of the above-mentioned Preparation Example 1.

[0088] According to the formula in Table 1 below, weigh each raw material (wt%), add the raw materials except glass fiber into a high mixing pot, add them into a twin-screw extruder through the main feed port after 5 minutes of high-speed mixing, add the glass fiber raw material into the side feed port, and finally granulate through twin-screw extrusion to obtain the product. The extrusion process is as follows: Zone 1 235°C, Zone 2 235°C, Zone 3 240°C, Zone 4 240°C, Zone 5 240°C, Zone 6 240°C, Zone 7 240°C, Zone 8 240°C, Zone 9 240°C, Zone 10 230°C; extruder screw speed 250 rpm; cooling water temperature 20°C, pelletizer speed 100 rpm.

[0089] Example 2

[0090] The main raw materials used in the preparation process of this embodiment are as follows:

[0091] The polybutylene terephthalate resin is 1100-211M, and its melt flow index is 30g / min. The test conditions are in accordance with ISO 1133 standard: 250°C, 2.16Kg; produced by Changchun Chemical (Jiangsu) Co., Ltd.;

[0092] The toughening agent is a random terpolymer of glycidyl methacrylate, with the brand name AX8900, produced by Arkema;

[0093] The glass fiber is ECS13-4.5-T438R, produced by Taishan Fiberglass, with a fiber diameter of 13um and a fiber length of 4.5mm;

[0094] The lubricant was zinc stearate (ZnST), produced by Faji Co., Ltd.

[0095] The antioxidants were SUNSHOW 168 and SUNSHOW 1010, produced by Xinxiu Chemical Co., Ltd.

[0096] The masterbatch is UN6269, produced by Cabot Co., Ltd.

[0097] The anti-hydrolysis agent is the anti-hydrolysis agent S-2 of the above-mentioned Preparation Example 1.

[0098] According to the formula in Table 1 below, weigh each raw material (wt%), add the raw materials except glass fiber into a high mixing pot, add them into a twin-screw extruder through the main feed port after 5 minutes of high-speed mixing, add the glass fiber raw material into the side feed port, and finally granulate through twin-screw extrusion to obtain the product. The extrusion process is as follows: Zone 1 235°C, Zone 2 235°C, Zone 3 240°C, Zone 4 240°C, Zone 5 240°C, Zone 6 240°C, Zone 7 240°C, Zone 8 240°C, Zone 9 240°C, Zone 10 230°C; extruder screw speed 400 rpm; cooling water temperature 30°C, pelletizer speed 20 rpm.

[0099] Embodiment 3 (hydrolysis resistant agent S-3):

[0100] The anti-hydrolysis agent used in the preparation process of this embodiment is the anti-hydrolysis agent S-3 of the above-mentioned Preparation Example 1, and the selection and source information of other main raw materials refer to Example 1.

[0101] According to the formula in Table 1 below, weigh each raw material (wt%), add the raw materials except glass fiber into a high mixing pot, add them into a twin-screw extruder through the main feed port after 5 minutes of high-speed mixing, add the glass fiber raw material into the side feed port, and finally granulate through twin-screw extrusion to obtain the product. The extrusion process is as follows: Zone 1 220°C, Zone 2 230°C, Zone 3 240°C, Zone 4 240°C, Zone 5 240°C, Zone 6 240°C, Zone 7 245°C, Zone 8 240°C, Zone 9 240°C, Zone 10 230°C; extruder screw speed 300 rpm; cooling water temperature 50°C, pelletizer speed 50 rpm.

[0102] Comparative Example 1-1:

[0103] The modified PBT was obtained by following the method of Example 1 except that the anti-hydrolysis agent S-1 was not added to the raw materials and other operations and conditions remained unchanged.

[0104] Comparative Example 1-2:

[0105] The modified PBT was prepared according to the method of Example 1, except that the anti-hydrolysis agent S-1 in the raw material was replaced by the anti-hydrolysis agent S9000 (Shanghai Langyi Co., Ltd.), and other operations and conditions remained unchanged.

[0106] Comparative Example 2-1:

[0107] The method of Example 2 is followed, except that no hydrolysis resistance agent S-2 is added to the raw materials, and all raw materials are post-baked at 110° C. for 4 hours before processing; other operations and conditions remain unchanged to obtain modified PBT.

[0108] Comparative Example 2-2:

[0109] The modified PBT was prepared according to the method of Example 2, except that the hydrolysis resistance agent S-2 in the raw material was replaced by ADR4468 (BASF), and other operations and conditions remained unchanged.

[0110] Comparative Example 3-1:

[0111] The modified PBT was obtained by following the method of Example 3, except that the anti-hydrolysis agent S-3 was not added to the raw materials, and other operations and conditions remained unchanged.

[0112] A total of 8 groups were included: 3 examples and 5 corresponding control groups.

[0113] Table 1 Raw material formula of examples and comparative examples

[0114]

[0115] The modified polybutylene terephthalate resin products prepared in the examples and comparative examples were tested for their properties using the following method:

[0116] Melt index: ISO 1133;

[0117] Density: ISO 1183;

[0118] Tensile strength: ISO 527;

[0119] Flexural strength: ISO 178;

[0120] Flexural modulus: ISO 178;

[0121] Simple supported beam unnotched impact: ISO 179;

[0122] Xenon lamp aging: Q / BYDQ-A1901.800.

[0123] Specifically, the hydrolysis resistance during the processing is comprehensively judged based on the melt index and mechanical properties data after modification: 1. The larger the melt index, the greater the degree of hydrolysis; 2. The worse the mechanical properties, the greater the degree of hydrolysis.

[0124] The mechanical properties of the embodiments and comparative examples are shown in Table 2:

[0125] Table 2 Performance of Examples and Comparative Examples

[0126]

[0127] It can be seen from the melt index and mechanical properties data in Table 2 that the macromolecular end-group anti-hydrolysis agent prepared by the present invention can well inhibit the hydrolysis during the processing of PBT, and on the basis of controlling the cost, well maintain the performance of the material, achieving the same performance as the purchased anti-hydrolysis agent (carbodiimide polymer). From the xenon lamp aging results, it is known that the macromolecular end-group anti-hydrolysis agent prepared by the present invention has a better xenon lamp aging resistance effect than the conventional anti-hydrolysis agent, and is better than the materials currently sold on the market.

Claims

1. A method for preparing a hydrolysis resistant agent, characterized in that: The following steps are involved: The RAFT agent containing a macromolecular group is mixed with a vinyl epoxy compound, an initiator and an organic solvent, and reacted in a protective gas environment to obtain the hydrolysis-resistant agent.

2. The preparation method according to claim 1, characterized in that: The RAFT agent containing a macromolecular group, wherein the macromolecular group contained is one or more of a group derived from dithioester, dithiocarbamate, xanthate, and trithiocarbonate, preferably a group derived from dithioester; Preferably, the RAFT agent containing a macromolecular group is one or more of benzyl dithiobenzoate, butyl dithiobenzoate, and isobutyl dithiobenzoate; and / or The vinyl epoxy compound is selected from one or more of vinyl methane oxide, vinyl butylene oxide and vinyl ethylene oxide, preferably one or more of vinyl ethylene oxide and vinyl butylene oxide; and / or The organic solvent is selected from one or more of furan, alcohol, and halogenated alkane compounds, preferably one or more of tetrahydrofuran (THF), methanol, ethanol, and dichloromethane, more preferably one or more of THF and ethanol; and / or The initiator is selected from azo compounds, preferably one or more of azobisisobutyronitrile (AIBN), azobisisovaleronitrile (AMBN), azobisisoheptanenitrile (ABVN), azobiscyclohexylcarbonitrile (ACCN), more preferably one or more of AIBN and ABVN; and / or The mass ratio of the RAFT agent containing a macromolecular group to the vinyl epoxy compound is 1:0.1-1000; and / or The mass ratio of the initiator to the vinyl epoxy compound is 1:10-1000; and / or The amount of the organic solvent is 1-100 times the mass of the vinyl epoxy compound.

3. The preparation method according to claim 1, characterized in that: The reaction temperature is 70-100°C and the reaction time is 24-120h; and / or The protective gas refers to a gas that is inert in the reaction, preferably nitrogen or argon; and / or After the reaction is completed, the reaction solution is allowed to stand for precipitation treatment, and then filtered to obtain a precipitate, and dried to obtain the anti-hydrolysis agent; preferably, the precipitation treatment is carried out for a precipitation time of 12-72 hours; preferably, the drying is vacuum drying, the drying temperature is 70-100°C, and the drying time is 12-72 hours.

4. A hydrolysis-resistant agent prepared by the method according to any one of claims 1 to 3; Preferably, the molecular weight of the anti-hydrolysis agent is 10,000-100,000.

5. An application of the anti-hydrolysis agent according to claim 4, characterized in that: It can be used in the field of thermoplastics processing, especially for the preparation of modified PBT, TPU and PLA.

6. A hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin, characterized in that: The anti-hydrolysis agent prepared by the method according to any one of claims 1 to 3 or the anti-hydrolysis agent according to claim 4 is specifically prepared from components containing the following mass percentages: Polybutylene terephthalate resin 35-90%, Glass fiber 10-50%, Toughener 3-20%, Lubricant 0.1-1%, Antioxidant 0.1-2%, Hydrolysis resistant agent 0.1-5%, Masterbatch 1-5%.

7. The glass fiber reinforced polybutylene terephthalate resin according to claim 6, characterized in that: The polybutylene terephthalate resin has a melt flow index of 5-60 g / min at 250° C. and 2.16 kg; and / or The glass fiber is an alkali-free chopped glass fiber; preferably, the fiber diameter is 10-15um and the fiber length is 1-5mm; Preferably, the glass fiber is one or more of ECS13-4.5-T438H, ECS13-4.5-T438R, TLD-CS-T436S; and / or The anti-hydrolysis agent is the anti-hydrolysis agent prepared by the method according to any one of claims 1 to 3 or the anti-hydrolysis agent according to claim 4, and may also contain existing known anti-hydrolysis agents, such as one or more of ADR4468 and S9000, and the blending ratio does not exceed 50wt%; and / or The toughening agent is selected from one or more of polyolefin elastomer, EPDM rubber, ethylene-acrylate, glycidyl methacrylate, preferably one or more of random terpolymers of ethylene-acrylate and glycidyl methacrylate (such as AX8900, PTW); and / or The lubricant is one or more of pentaerythritol stearate (PETS), zinc stearate (ZNST), polyethylene wax; and / or The antioxidant is one or more of SUNSHOW 1010, SUNSHOW 168, and SUNSHOW 5585; and / or The masterbatch is one or more of UN6269, XP6621A and 3600.

8. A method for preparing the hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin according to claim 6 or 7, characterized in that the steps include: The raw materials except glass fiber are mixed and added to the main feeding port of the twin-screw extruder, and the glass fiber is added to the side feeding port, and extruded into granules to obtain hydrolysis-resistant glass fiber reinforced polybutylene terephthalate resin.

9. The preparation method according to claim 8, characterized in that: The twin-screw extruder is set at a temperature of 220-245° C. and a screw speed of 200-500 rpm; and / or In the extrusion granulation, the cooling water temperature is 10-50° C. and the pelletizer speed is 10-100 rpm.

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