Thermoplastic acrylate copolymer as well as preparation method and application thereof

Abstract

The invention relates to a thermoplastic acrylate copolymer as well as a preparation method and application thereof. According to the invention, a proper proportion of the surface hydrophobic agent with excellent compatibility with the resin is added into the resin to improve the surface water contact angle after molding and maintain high light transmittance, so that the body fluid in the medical product has proper flowability and good detection light transmittance in the detection process to ensure the accuracy of the detection result. The thermoplastic acrylate copolymer resin has a proper surface water contact angle and excellent optical performance, and can be used for materials in the field of medical detection consumables with complex structures.

Description

TECHNICAL FIELD

[0001] The present application relates to a thermoplastic polymer material, in particular to a thermoplastic acrylate copolymer and its preparation method and use. BACKGROUND

[0002] The thermoplastic acrylate copolymer is a kind of thermoplastic polymer material polymerized by copolymerizable monomers. This kind of polymer material is widely used in automobile, optics, home appliance, medical, cosmetic packaging, lighting and other markets due to its special thermoplastic properties and excellent optical properties.

[0003] Among them, the main product form of the thermoplastic acrylate copolymer for medical detection is very complex and fine structure, which also includes many capillaries and small size channels, and the microfluidic chip for medical detection is particularly complex, so in order to ensure the good fluidity of the body fluid in the detection device, the surface of the product needs to be treated to be hydrophobic, and the general treatment method is coating, but it is obviously very difficult to realize the coating of the inner surface of such a fine and complex structure channel. At the same time, since the detection instrument realizes the analysis of the body fluid by light detection, the material also needs to have very high light transmittance.

[0004] The general transparent thermoplastic acrylate copolymer has a surface hydrophobic angle of only 60-65°, which indeed cannot meet the requirements of the body fluid fluidity of the medical detection device in the actual application process.

[0005] The CN116333440A patent mentions that the surface hydrophobicity is improved by adding an antistatic agent, and it mentions that the addition of such an additive will affect the optical transmittance and other properties, but most of the medical detection materials need high transmittance to realize online instrument detection, and the general requirement for 3mm transmittance is more than 92%, the highest transmittance of this patent is only 85%, and the maximum surface hydrophobic angle is only 60°, which cannot completely solve the requirements of the medical detection material for the body fluid fluidity and transmittance.

[0006] The CN115819863A patent mentions that a large amount of wax and organosiloxane, stearic acid compound, C10-C28 saturated alkyl acid, C10-C28 alkyl alcohol, C10-C28 alkyl amide, C8-C22 unsaturated alkyl acid or C8-C18 unsaturated alkyl acid amide hydrophobic agent is added, the purpose is to realize a large water contact angle, so that the material surface is not wet, but it is not realized that the too large water contact angle and the too low light transmittance of the optical detection material are not conducive to its actual use, and only qualitative test is carried out, and the specific range of the hydrophobic angle index is not directly specified. SUMMARY

[0007] To solve the above technical problems, the present application provides a thermoplastic acrylic ester copolymer, a preparation method and use thereof. The present application improves the surface hydrophobicity of the product by adding a surface hydrophobicity agent which is more compatible with the thermoplastic acrylic ester copolymer in the polymer, so that the product has excellent body fluid flowability and does not affect the optical properties of the resin itself.

[0008] To achieve the above-mentioned object, the technical scheme adopted by the present application is as follows:

[0009] A thermoplastic acrylic ester copolymer is prepared from the following raw materials:

[0010] I. First comonomer: methacrylate monomer, 65-99 parts by mass, preferably 83-98 parts by mass;

[0011] II. Second comonomer: vinyl monomer, 1-35 parts by mass, preferably 2-17 parts by mass;

[0012] III. Surface hydrophobic agent, 0.01-0.3 parts by mass, preferably 0.05-0.25 parts by mass, based on 100 parts by mass of the thermoplastic acrylic ester copolymer;

[0013] The surface water contact angle of the thermoplastic acrylic ester copolymer is controlled at 70-90°; the light transmittance of a 3mm thick standard optical sample is ≥92%, and the haze is ≤0.5%.

[0014] The thermoplastic acrylic ester copolymer of the present application has excellent demolding performance and excellent liquid flowability while maintaining excellent light transmittance, significantly improving the problems of poor molding of medical detection devices, liquid backflow, and poor optical detection.

[0015] As a preferred scheme of the present application, the weight average molecular weight of the thermoplastic acrylic ester copolymer is 50,000-200,000, preferably 100,000-150,000.

[0016] As a preferred scheme of the present application, the amount of methacrylate monomer in the raw materials of the thermoplastic acrylic ester copolymer is 65-99 parts by mass, preferably 83-98 parts by mass; the amount of vinyl monomer is 1-35 parts by mass, preferably 2-17 parts by mass, based on the total mass of the two monomers being 100 parts by mass.

[0017] As a preferred scheme of the present application, the methacrylate monomer is selected from one or more of methyl methacrylate, ethyl methacrylate, and butyl methacrylate, preferably methyl methacrylate.

[0018] As a preferred scheme of the present application, the vinyl monomer is selected from one or more of acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, styrene, a-methyl styrene, preferably methyl acrylate and / or styrene.

[0019] As a preferred scheme of the present application, the surface hydrophobicity aid is selected from one or more of C10-C20 alkyl acid, C10-C20 alkyl alcohol and C10-C20 alkyl ester, including one or more of hexadecanoic acid, octadecanoic acid, methyl hexadecanoate, methyl octadecanoate, butyl octadecanoate, stearyl alcohol phosphate; particularly preferably one or more of methyl hexadecanoate, methyl octadecanoate, butyl octadecanoate, stearyl alcohol phosphate. Methyl hexadecanoate, methyl octadecanoate, butyl octadecanoate and stearyl alcohol phosphate have ester bonds closer to the molecular structure of PMMA, better compatibility and less impact on optical properties.

[0020] The polymerization process of the thermoplastic acrylic copolymer described in the present application can be any one of bulk polymerization, solution polymerization and suspension polymerization. From the perspective of product performance and process matching, intermittent or continuous bulk polymerization is preferred, and continuous bulk polymerization is more preferred.

[0021] A preparation method of a thermoplastic acrylic copolymer, comprising the following steps:

[0022] S1: mixing methacrylate monomer, vinyl monomer, initiator and chain transfer agent to prepare reaction liquid A, and performing polymerization reaction to prepare slurry A;

[0023] S2: adding a surface hydrophobic agent to the slurry A to prepare slurry B;

[0024] S3: performing devolatilization and extrusion on the slurry B.

[0025] As a preferred scheme, in step S2, the surface hydrophobic agent is added to the slurry A after being heated and melted.

[0026] As a preferred scheme, the initiator in S1 includes one or more of dibenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxyisobutyrate, tert-butyl peroxyacetate, dicumyl peroxide, 1,1-bis-(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-butyl peroxybenzoate, tert-butyl hydroperoxide, cumene hydroperoxide and tert-butyl hydroperoxide; preferably tert-butyl peroxy-3,5,5-trimethylhexanoate and / or dicumyl peroxide, more preferably dicumyl peroxide.

[0027] As a preferred embodiment, in S1, the amount of initiator added is 0.001-0.1 parts by mass, preferably 0.01-0.03 parts by mass, based on the sum of the masses of the two monomers being 100 parts by mass.

[0028] As a preferred embodiment, in S1, the chain transfer agent includes one or more of n-butanethiol, tert-butanethiol, n-octanethiol, isooctanethiol, n-dodecylthiol, and tert-dodecylthiol, preferably n-octanethiol.

[0029] As a preferred embodiment, in S1, the amount of chain transfer agent added is 0.03-0.7 parts by mass, preferably 0.2-0.5 parts by mass, based on the sum of the masses of the two monomers being 100 parts by mass.

[0030] As a preferred option, in S1 and S2, the reactor is a fully mixed-flow high-pressure reactor.

[0031] As a preferred option, the reaction temperature in S1 and S2 is 120-150℃.

[0032] As a preferred embodiment, in S3, the devolatilization employs a static devolatilizer and / or a screw extrusion devolatilizer, preferably a screw extrusion devolatilizer.

[0033] Preferably, in step S3, the devolatilization temperature is controlled at 230-260℃; the vacuum degree is controlled at 2-20KPa to remove most of the methacrylate monomers and vinyl monomers, and the resulting product contains 100-3000ppm of surface hydrophobic additives.

[0034] The thermoplastic acrylate copolymers described in this invention are used in the field of medical testing, such as medical testing consumables, microfluidic chips, blood collection vessels, and other medical materials with complex structures that require good fluid flowability and ultra-high light transmittance. Detailed Implementation

[0035] The present invention will be further illustrated below with specific embodiments. These embodiments are merely illustrative and do not limit the scope of the invention.

[0036] Unless otherwise specified, the raw materials and reagents used in the following embodiments of the present invention were all purchased from commercial sources. The main raw material information is shown in Table 1:

[0037] Table 1 Information on Main Raw Materials

[0038] Raw material name Other name or abbreviation Grade Supplier Methyl methacrylate MMA Industrial grade Wanhua Methyl acrylate MA Industrial grade Wanhua Styrene SM Industrial grade Wanhua Tert-butyl peroxy-3,5,5-trimethylhexanoate TBPMH Industrial grade Guo Yao N-octyl mercaptan NOM Industrial grade Chevron Palmitic acid / Industrial grade Lianlong Methyl palmitate / Industrial grade Lianlong Methyl stearate / Industrial grade Lianlong Microcrystalline paraffin wax / Industrial grade Lianlong

[0039] The following are the methods for testing the structure and properties of polymers:

[0040] Molecular weight determination: Molecular weight was determined by gel electrophoresis (GPC) with tetrahydrofuran (THF) as the mobile phase and a parallax refractive index detector. Monodisperse PMMA was used as the standard sample. Instrument manufacturer: Agilent Technologies; Instrument model: 1260 Infinity; Test standard: GB / T 21863-2008.

[0041] Transmittance / Haze: The optical properties of a 3mm standard optical film, obtained through injection molding, can be measured using a colorimeter, including total light transmittance and haze. Instrument model: Hunterlab VIS; Test standards: Haze ISO 14782, transmittance ISO13148.

[0042] Surface hydrophobicity angle test: The surface hydrophobicity angle of a standard 3mm optical film, produced by injection molding, is measured using a contact angle tester (instrument model: German). DSA100, test standard ASTM D7334.

[0043] Example 1

[0044] S1. Add 95 kg of methyl methacrylate, 5 kg of methyl acrylate, 10 g of initiator TBPMH and 150 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0045] S2. Add 250g of hexadecanoic acid to mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B.

[0046] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0047] Example 2

[0048] S1. Add 90 kg of methyl methacrylate, 10 kg of methyl acrylate, 8 g of initiator TBPMH and 160 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0049] S2. Add 200g of methyl palmitate to mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B.

[0050] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0051] Example 3

[0052] S1. Add 75 kg of methyl methacrylate, 25 kg of methyl acrylate, 6 g of initiator TBPMH and 180 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0053] S2. Add 80g of methyl stearate to mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B;

[0054] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0055] Example 4

[0056] S1. Add 95 kg of methyl methacrylate, 5 kg of styrene, 10 g of initiator TBPMH and 150 g of n-octyl mercaptan to the mixing tank A and mix to prepare reaction solution A; add reaction solution A to the reaction vessel A to carry out the polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h, and obtain slurry A.

[0057] S2. Add 250g of hexadecanoic acid and 30g of methyl octadecanoate to mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B.

[0058] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0059] Example 5

[0060] S1. Add 95 kg of methyl methacrylate, 5 kg of methyl acrylate, 10 g of initiator TBPMH and 150 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0061] S2. Add 250g of hexadecanoic acid and 50g of methyl hexadecanoate into mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B.

[0062] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0063] Comparative Example 1

[0064] S1. Add 95 kg of methyl methacrylate, 5 kg of methyl acrylate, 10 g of initiator TBPMH and 150 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0065] S2. Add 450g of hexadecanoic acid to mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B.

[0066] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0067] Comparative Example 2

[0068] S1. Add 95 kg of methyl methacrylate, 5 kg of methyl acrylate, 10 g of initiator TBPMH and 150 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0069] S2. Add slurry A to the extruder and devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product by extrusion and granulation.

[0070] Comparative Example 3

[0071] S1. Add 95 kg of methyl methacrylate, 5 kg of methyl acrylate, 10 g of initiator TBPMH and 150 g of n-octyl mercaptan into mixing tank A and mix to prepare reaction solution A; add reaction solution A into reactor A to carry out polymerization reaction, control the polymerization temperature at 135℃ and the residence time at 2 h to obtain slurry A.

[0072] S2. Add 100g of microcrystalline wax to mixing tank B, maintain the temperature inside the tank at 90-110℃ and fully melt and mix to prepare auxiliary agent solution A; mix slurry A and auxiliary agent solution A to obtain slurry B.

[0073] S3. Add slurry B to the extruder devolatilizer, control the devolatilization temperature at 250℃, the vacuum degree at 2.5KPa, and the residence time at 5min, and obtain the product through extrusion and granulation.

[0074] The copolymers prepared in each embodiment and comparative example were tested for molecular weight, molecular weight distribution, transmittance, haze, and hydrophobic angle. The test results are shown in Table 2.

[0075] Table 2 Performance Test Results

[0076] Test item Mw PDI Transmittance Haze Hydrophobic angle Unit / / ％ ％ Degree Example 1 11.2 million 1.81 92.60 0.1 79.5 Example 2 11.4 million 1.83 92.70 0.08 84.6 Example 3 11.3 million 1.91 92.70 0.07 75.9 Example 4 11.6 million 1.84 92.50 0.12 81.2 Example 5 11.1 million 1.79 92.50 0.1 75.6 Comparative example 1 12.0 million 1.87 92.00 0.67 105 Comparative example 2 11.2 million 1.81 92.70 0.06 61 Comparative example 3 11.5 million 1.83 75.00 15.4 89

[0077] The test results of the thermoplastic acrylate copolymers with good optical properties and surface hydrophobicity prepared by Examples 1-5 show that the method of the present invention can realize the preparation of thermoplastic acrylate copolymers for medical testing, and have better optical properties and optimal surface hydrophobicity.

[0078] Comparing Comparative Example 1 with Example 1, the amount of hexadecanoic acid added in Comparative Example 1 was increased from 250g to 450g, and the hydrophobic angle of the product surface was increased to 105°. The excessively large hydrophobic angle caused the liquid to flow too fast and could not fill the detection holes along the flow path, resulting in invalid detection. At the same time, the transmittance and haze both deteriorated, which affected the detection light signal of the detection instrument and caused a large deviation in the detection results.

[0079] Comparing Comparative Example 2 with Examples 1-5, Comparative Example 2 did not add any hydrophobic agent, and the hydrophobic angle was reduced to 61°, resulting in a slow liquid flow rate. When the detection cavity was filled, severe backflow occurred, causing mutual contamination of the detection liquids and affecting the detection results.

[0080] By comparing Comparative Example 3 with Examples 1-5, although the hydrophobic angle of Comparative Example 3 was increased to 89° by adding a small amount of microcrystalline wax, the light transmittance and haze were severely reduced, and it was basically impossible to pass through the detection light of the detection instrument, making it unusable.

Claims

1. A thermoplastic acrylate copolymer, comprising the following raw materials: I. a first comonomer: a methacrylate monomer, 65-99 parts by mass, preferably 83-98 parts by mass; II. a second comonomer: a vinyl monomer, 1-35 parts by mass, preferably 2-17 parts by mass; III. a surface hydrophobic agent, 0.01-0.3 parts by mass, preferably 0.05-0.25 parts by mass, based on 100 parts by mass of the thermoplastic acrylate copolymer; the surface water contact angle of the thermoplastic acrylate copolymer is controlled at 70-90°; the light transmittance of a 3mm-thick standard optical sample is ≥92%, and the haze is ≤0.5%. The weight average molecular weight of the thermoplastic acrylate copolymer is 50,000-200,000, preferably 100,000-150,000. The amount of the methacrylate monomer is 65-99 parts by mass, preferably 83-98 parts by mass; the amount of the vinyl monomer is 1-35 parts by mass, preferably 2-17 parts by mass, based on the total mass of the two monomers as 100 parts by mass. The methacrylate monomer is selected from one or more of methyl methacrylate, ethyl methacrylate, and butyl methacrylate, preferably methyl methacrylate. The vinyl monomer is selected from one or more of acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, styrene, and α-methyl styrene, preferably methyl acrylate and / or styrene.

2. The thermoplastic acrylate copolymer according to claim 1, characterized in that, The surface hydrophobic agent is selected from one or more of C10-C20 alkyl acids, C10-C20 alkyl alcohols, and C10-C20 alkyl esters, such as one or more of hexadecanoic acid, octadecanoic acid, methyl hexadecanoate, methyl octadecanoate, butyl octadecanoate, and stearyl alcohol phosphate; preferably one or more of methyl hexadecanoate, methyl octadecanoate, butyl octadecanoate, and stearyl alcohol phosphate.

3. The thermoplastic acrylate copolymer of claim 1, wherein, 7.A method for preparing the thermoplastic acrylate copolymer of any one of claims 1-6, comprising the following steps: S1: mixing a methacrylate monomer, a vinyl monomer, an initiator, and a chain transfer agent to prepare a reaction solution A, and performing a polymerization reaction to prepare a slurry A; S2: adding a surface hydrophobic agent to the slurry A to prepare a slurry B; and S3: performing devolatilization and extrusion on the slurry B.

4. The thermoplastic acrylate copolymer of claim 1, wherein, The initiator in S1 includes one or more of dibenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxy-isobutyrate, tert-butyl peroxy-acetate, dicumyl peroxide, 1,1-bis-(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-butyl peroxy-benzoate, tert-butyl hydroperoxide, cumene hydroperoxide, and tert-butyl hydroperoxide; preferably tert-butyl peroxy-3,5,5-trimethylhexanoate and / or dicumyl peroxide, more preferably dicumyl peroxide; and / or, the amount of the initiator is 0.001-0.1 parts by mass, preferably 0.01-0.03 parts by mass, based on 100 parts by mass of the total mass of the two monomers.

5. The thermoplastic acrylate copolymer of claim 1, wherein ​ 6. The thermoplastic acrylate copolymer of claim 1, wherein ​ ​ ​ ​ ​ 8. The method of claim 7, wherein, ​ 9. The method of claim 7, wherein, The S1 chain transfer agent includes one or more of n-butyl mercaptan, t-butyl mercaptan, n-octyl mercaptan, iso-octyl mercaptan, n-dodecyl mercaptan and t-dodecyl mercaptan, preferably n-octyl mercaptan; and / or, the chain transfer agent is added in an amount of 0.03-0.7 parts by mass, preferably 0.2-0.5 parts by mass, based on 100 parts by mass of the two monomers.

10. Use of the thermoplastic acrylate copolymer of any one of claims 1 to 6 or the thermoplastic acrylate copolymer prepared by the process of any one of claims 7 to 9 in the field of medical diagnostics, preferably medical diagnostic consumables, microfluidic chips, bloodware.