Grafted latex for high impact high weathering asa resin and its preparation method and application

Abstract

The present application relates to a kind of grafting latex for high impact high weathering ASA resin and its preparation method and application.The preparation method of the grafting latex includes:1) polybutyl acrylate latex, and optionally emulsifier, chain transfer agent, complexing agent, reducing agent, reducing agent, water is added to reactor and stirred uniformly, then heated to polymerization temperature;2) copolymerization monomer, initiator, crosslinking agent are added dropwise to reactor and polymerization is carried out, wherein crosslinking agent is completed in the first 1 / 3 time period of polymerization reaction, and the grafting latex for ABS resin is prepared after reaction is completed.The present application adopts the mode that crosslinking agent is added in the early stage of polybutyl acrylate latex emulsion grafting, improves the integrity of grafting latex core-shell structure in subsequent SAN resin double screw mixing process, so that dispersed phase rubber particle regularity is kept.Thereby further improve the cavity effect of rubber dispersed phase particle, and promote the impact resistance of ASA resin.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of polymer preparation, and particularly relates to a polymerization method for preparing a grafting latex for preparing high-impact high-weather-resistance ASA resin. BACKGROUND

[0002] The ASA resin is also commonly known as weather-resistant ABS resin. Since the polyacrylate (mainly butyl ester) rubber is used to replace the polybutadiene rubber in the ABS resin, the ASA resin does not contain a large amount of C=C, and the weather resistance of the resin is significantly improved under ultraviolet light.

[0003] It is known that the above two resins both belong to two-phase structure polymers, and the design concept is to toughen the brittle SAN resin by using the dispersed phase rubber. Since the C-C connected with the C=C double bond has a lower internal rotation potential barrier, the ASA resin using the polyacrylate rubber is generally less flexible than the ABS resin using the polybutadiene rubber, and the toughening effect on the SAN resin is also poor. Therefore, how to improve the impact strength of the ASA resin while maintaining the weather resistance is the main product research direction in the industry.

[0004] At present, the impact strength of the ASA resin is mainly improved by the following methods:

[0005] 1) Adding a rubber with better impact performance as the toughening dispersed phase of the SAN matrix. For example, the patent CN101633769A improves the impact performance of the ASA resin by mixing the polydiene latex into the polybutyl acrylate latex, and mixing the powder nitrile rubber, powder styrene-butadiene rubber and powder polybutadiene rubber into the prepared graft copolymer. As described above, this method introduces unsaturated carbon-carbon double bonds, which will cause the weather resistance of the ASA resin to decrease.

[0006] 2) Developing a new two-phase structure according to the toughening mechanism. For example, the patent US4224419A uses a double-distributed particle size dispersed phase, i.e., polyacrylate rubber, to realize the dual improvement of the SAN resin toughness and coloring performance; generally, the dispersed phase with different particle sizes has different effects on the toughening mechanism of the matrix resin, and the large particle size tends to induce a silver line, and the small particle size tends to induce a shear band.

[0007] 3) Improving the core-shell structure of the rubber phase. For example, the patent CN105764943B uses a multi-layer core-shell structure (polybutyl acrylate-poly styrene-SAN) to improve the comprehensive mechanical properties of the ASA resin.

[0008] 4) Adjusting the cross-linking structure of the rubber phase. For example, the patents EP-A 0535456 and DE-A 4006643 propose that when DCPA is used as a cross-linking agent in the preparation of the rubber phase, the prepared resin has improved impact resistance.

[0009] 5) Introducing other monomers into the rubber phase to improve the copolymerization. For example, patent CN105008421B introduces N-vinyl monomers, and US5120788 introduces C atom number 8-20 acrylate monomers in the shell layer of the rubber phase to improve the impact resistance of the ASA resin.

[0010] However, the inventors of the present application found in experimental research that during the preparation of the ASA resin by blending the rubber dispersed phase with a core-shell structure and the SAN resin matrix, the above-mentioned schemes all have different degrees of dispersion phase fragmentation problems. Controlling the dispersion effect of the dispersed phase and the integrity after dispersion is the key to affecting the toughening efficiency of the SAN matrix.

[0011] Therefore, it is urgent to provide a method which can conveniently prepare an ASA resin with high impact resistance and high weather resistance. SUMMARY

[0012] Therefore, the purpose of the present application is to provide a grafting latex for high-impact and high-weather-resistance ASA resin and a preparation method thereof. The grafting latex is prepared by adding a crosslinking agent in the early stage (first 1 / 3 time) of the grafting polymerization reaction of polybutyl acrylate latex, so that the grafting latex has a shell layer with a gradient crosslinking structure. When further dispersed in the SAN matrix, the shell layer with the gradient crosslinking structure can realize the binding effect on the dispersed phase rubber, thereby avoiding the damage of the dispersed phase during the double-screw blending process and improving the impact resistance of the resin.

[0013] The purpose of the present application is also to provide a high-impact and high-weather-resistance ASA resin. The raw material is the above-mentioned grafting latex. During the subsequent preparation of the ASA resin by blending the SAN resin with the double-screw, the integrity of the rubber phase particles as the dispersed phase is maintained, the void effect of the rubber dispersed phase particles is not affected by the physical process of the double-screw blending, and the prepared ASA resin not only ensures high weather resistance but also has better impact strength.

[0014] To achieve the above-mentioned purposes, the technical solutions adopted by the present application are as follows:

[0015] In a first aspect, the present application provides a preparation method of a grafting latex for high-impact and high-weather-resistance ASA resin. The method is to mix polybutyl acrylate latex and a comonomer under the condition of a crosslinking agent and an initiator to perform a polymerization reaction, thereby obtaining an ASA grafting latex.

[0016] The crosslinking agent is added at the first 1 / 3 time of the polymerization reaction, for example, at the time points of 1 / 10, 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, 1 / 4, 1 / 3, etc. of the polymerization reaction. It can also be understood that the addition time of the crosslinking agent accounts for a certain proportion of the polymerization reaction time, and the crosslinking agent is usually added from the beginning of the polymerization reaction and the time is counted.

[0017] As a preferred embodiment of the present application, the crosslinking agent is added continuously, preferably dropwise; the crosslinking agent is added dropwise within the first 1 / 3 of the polymerization reaction, preferably within 1 / 5-1 / 3 of the beginning of the polymerization reaction.

[0018] As a preferred embodiment of the present application, the method for preparing the grafting latex for the high-impact high-weather-resistance ASA resin comprises the following steps:

[0019] 1) Base laying stage: the polybutyl acrylate latex, and optionally emulsifier, chain transfer agent, complexing agent, reducing agent, reducing agent, water are added to the reactor and stirred uniformly, and then heated to the polymerization temperature;

[0020] 2) Continuous dropwise polymerization stage: the comonomer and initiator are added dropwise to the reactor for polymerization, wherein the crosslinking agent is added within the first 1 / 3 of the polymerization reaction, and the grafting latex for the ABS resin is prepared after the reaction is completed.

[0021] As a preferred embodiment of the present application, in step 1), the polymerization temperature is 40-90℃, such as 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, etc., preferably 50-80℃.

[0022] As a preferred embodiment of the present application, in step 2), the comonomer and initiator can be added separately or mixed and added simultaneously; the comonomer and initiator are added dropwise, which is more conducive to forming a shell layer on the surface of the polybutyl acrylate latex by controlling the low concentration of the comonomer and initiator in the system; the dropwise addition time of the comonomer and initiator is 1-5h, such as 1h, 2h, 3h, 4h, 5h, etc.

[0023] As a preferred embodiment of the present application, in step 2), the polymerization time is 1-5h, such as 1h, 2h, 3h, 4h, 5h, etc., preferably 2-4h;

[0024] Preferably, the polymerization reaction is considered to be completed when the total conversion rate of the comonomer is >95%, such as 95.1%, 96%, 97%, 98%, 99%, 100%, etc.

[0025] As a preferred embodiment of the present application, in step 1), the polybutyl acrylate latex has a particle size of 400-600nm, such as 400nm, 450nm, 500nm, 550nm, 600nm, etc., and a solid content of 30-50wt%, such as 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, etc.

[0026] The polybutyl acrylate latex is a product available in the market, and can be a common commercially available product or can be prepared by itself. The preparation method is a known process in the prior art, and the present application does not make specific limitations. For example, the technical solution disclosed in patent GB1293791A can be referred to for preparation, and will not be described here.

[0027] As a preferred embodiment of the present application, in step 2), the comonomer is selected from a mixture of a vinyl cyanide and an aromatic vinyl compound; preferably, the vinyl cyanide is acrylonitrile, and the aromatic vinyl compound is styrene.

[0028] Preferably, in the mixture, the mass ratio of the vinyl cyanide to the aromatic vinyl compound is 1:2-5, such as 1:2, 1:3, 1:4, 1:5, etc.

[0029] As a preferred embodiment of the present application, in step 2), the initiator is selected from one or more of C3-C18 organic peroxides, such as C3, C5, C8, C10, C15, C18, etc. organic peroxides, preferably one or more of dicumyl peroxide, cumyl hydroperoxide, t-butyl hydroperoxide.

[0030] As a preferred embodiment of the present application, in step 2), the crosslinking agent is selected from one or more of aromatic compounds having two vinyl groups, acrylate compounds, preferably one or more of divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate.

[0031] As a specific embodiment of the present application, in step 1), the raw material further includes an optional emulsifier, a chain transfer agent, a complexing agent, a reducing agent, a reducing agent, water, all of which are conventionally selected in the art, and the present application does not have specific requirements.

[0032] Preferably, the emulsifier is selected from one or more of alkyl sulfate, alkyl sulfonate, alkyl benzene sulfonate, alkyl naphthalene sulfonate;

[0033] Preferably, the chain transfer agent is selected from one or more of n-dodecyl mercaptan, t-dodecyl mercaptan, n-octyl mercaptan, iso-octyl mercaptan;

[0034] Preferably, the complexing agent is selected from one or more of trisodium nitrilotriacetate, disodium ethylenediaminetetraacetate, tetrasodium ethylenediaminetetraacetate, sodium pyrophosphate, sodium hexametaphosphate, preferably disodium ethylenediaminetetraacetate;

[0035] Preferably, the reducing agent is selected from one or more of ferrous sulfate, ferrous chloride, sodium bisulfite, preferably ferrous sulfate;

[0036] Preferably, the co-reductant is selected from one or more of sodium hydrosulfite, sodium formaldehyde sulfoxylate, erythorbic acid, glucose, lactose, preferably sodium formaldehyde sulfoxylate.

[0037] As a preferred embodiment of the present application, the amount of the co-monomer is 50-200% of the dry weight of the polybutyl acrylate latex;

[0038] Preferably, the mass ratio of the co-monomer, crosslinking agent, initiator, emulsifier, chain transfer agent, complexing agent, reducing agent, co-reductant, water is 100:(0.5-5):(0.1-1):(0-5):(0-1):(0-1):(0-0.01):(0-1):(0-200), for example 100:(0.5, 1, 2, 3, 4, 5, etc):(0.1, 0.3, 0.5, 0.7, 1, etc):(0, 0.1, 0.5, 1, 2, 3, 4, 5, etc):(0, 0.1, 0.3, 0.5, 0.7, 1, etc):(0, 0.1, 0.3, 0.5, 0.7, 1, etc):(0, 0.001, 0.003, 0.005, 0.007, 0.01, etc):(0, 0.1, 0.3, 0.5, 0.7, 1, etc):(0, 1, 10, 50, 100, 150, 200, etc), more preferably 100:(0.5-5):(0.1-1):(1-5):(0.1-1):(0.1-1):(0.001-0.01):(0.1-1):(80-200).

[0039] In a second aspect, the present application provides a grafting latex for high impact high weather resistance ASA resin prepared according to the method described above.

[0040] In a third aspect, the present application provides use of the emulsion for high impact high weather resistance ASA resin in the preparation of ASA resin.

[0041] Illustratively, the present application provides a high impact high weather resistance ASA resin, which is prepared by coagulation and demulsification of the grafting latex for high impact high weather resistance ASA resin to obtain ASA rubber powder, and then by blending and extrusion with SAN resin.

[0042] As a preferred embodiment of the present application, the SAN resin is selected from styrene-acrylonitrile copolymer with acrylonitrile copolymerization mass ratio of 23-25%;

[0043] Preferably, the SAN resin has a weight average molecular weight of 100-140 thousand, for example 100, 110, 120, 130, 140 thousand.

[0044] The SAN resin of the present application can be prepared by any known method (such as bulk polymerization method), or can be directly purchased from commercially available products (for example, LG80HF, DQ SAN327, CHIME IPN128), without any limitation.

[0045] The method of coagulating and demulsifying the ASA resin with grafted latex is known to those skilled in the art, and can be operated according to the existing method, which is not specifically limited in the present application. For example, as one of the preferred methods, the ASA resin is mixed with inorganic salt (especially one or more of IIA main group element salts, such as magnesium sulfate, calcium chloride, barium chloride, etc.; the inorganic salt is preferably added in an amount of 2-5 wt% based on the latex), and then high-temperature curing (for example, curing at 65-95℃ for 1-5h), followed by filtration and drying to obtain ASA rubber powder.

[0046] As a preferred embodiment of the present application, the mass ratio of the ASA rubber powder and the SAN resin mixed is (30-50):(40-80).

[0047] As a preferred embodiment of the present application, the temperature used in the blending and extrusion is 220-260℃, and then cooling and granulation to obtain high-impact high-weather-resistance ASA resin.

[0048] Compared with the prior art, the technical scheme of the present application has the beneficial effects that:

[0049] By adding crosslinking agent in the early stage of grafting polymerization reaction of polybutyl acrylate latex emulsion, the integrity of the core-shell structure of the grafted latex in the subsequent blending and extrusion process with SAN resin is improved, so that the regularity of the dispersed phase rubber particles is maintained, thereby improving the cavity effect of the dispersed phase rubber particles when the resin is subjected to external impact, and further improving the impact resistance of the resin. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 is an electron microscope image of the ASA resin prepared by using the ASA grafted latex provided in Example 1 as raw material;

[0051] Figure 2 is an electron microscope image of the ASA resin prepared by using the ASA grafted latex provided in Comparative Example 1 as raw material. DETAILED DESCRIPTION

[0052] The present application will be further described below through specific examples, which are only used to illustrate the present application and do not limit the scope of the present application.

[0053] Unless otherwise specified, the raw materials used in the following specific embodiments of the present application can be obtained by commercial means, wherein:

[0054] Polybutyl acrylate latex: prepared according to the method disclosed in patent GB1293791A, particle size 427 nm, solid content 43.2%;

[0055] SAN resin: brand 80HF, purchased from LG Chemical, weight average molecular weight 123,000;

[0056] Other reagents are purchased from Aladdin, Merck, and pharmaceutical manufacturers such as National Pharmaceutical.

[0057] The main analysis methods used in the following specific embodiments of the present application are as follows:

[0058] (1) Latex particle size: 1 g of latex is mixed with 100 g of deionized water, and the average particle size is measured according to the dynamic laser scattering method using a Malvern Mastersizer laser particle size analyzer;

[0059] (2) Latex solid content / conversion rate: 2 g of grafted latex is dried at 180℃ using a Mettler HC103 moisture analyzer to obtain the solid content; the grafting process conversion rate can be calculated according to the feed formula, or the grafting process conversion rate can be calculated using gas chromatography to test the residual comonomer;

[0060] (3) Impact performance test: the prepared ASA resin is sampled and impact performance tested according to GB / T1043 hard plastic simple beam impact test method;

[0061] (4) Resin weather resistance: ASA resin samples are tested for ultraviolet aging acceleration test according to ASTM G154 method, and the color difference ΔE of the resin under 60℃, 500h ultraviolet light (0.89W / m 2 , 340nm) irradiation is compared to compare the weather resistance of the sample;

[0062] (5) Electron microscope test: the injection molded ASA resin is sliced after being frozen in liquid nitrogen, and is observed under a transmission electron microscope after being stained with ruthenium tetroxide.

[0063] Example 1

[0064] Preparation of grafted latex for high impact high weather resistance ASA resin:

[0065] 1) Base laying stage

[0066] Polybutyl acrylate latex 118 parts (dry basis 50 parts, particle size 427 nm, solid content 43.2%), sodium dodecyl sulfate 1 part, tertiary dodecyl mercaptan 0.25 parts, ethylenediaminetetraacetic acid disodium 0.3 parts, ferrous sulfate 0.002 parts, sodium formaldehyde sulfoxylate 0.4 parts, deionized water 40 parts are added into the reaction kettle, and stirred and mixed uniformly, and heated to 65℃;

[0067] 2) Continuous polymerization stage

[0068] Maintain 65 ℃ constant temperature, respectively, to the reaction system uniform speed drop 50 parts of the copolymer mixture (styrene 38 parts, acrylonitrile 12 parts), 0.3 parts of cumene hydroperoxide, 1 parts of divinylbenzene, start the polymerization reaction; wherein the copolymer and cumene hydroperoxide 3h drop is completed, divinylbenzene 1h drop is completed; drop is completed after constant temperature reaction, sampling monitoring system copolymer conversion rate is 97.3% when stop reaction, the polymerization reaction time is 5h (crosslinking agent in the polymerization reaction of the first 1 / 5 period of time drop is completed), cooling get ASA resin with grafting latex.

[0069] Example 2

[0070] Preparation of high impact high weathering ASA resin with grafting latex:

[0071] 1) bottom stage

[0072] The polybutyl acrylate latex 118 parts (dry base 50 parts, particle size 427nm, solid content 43.2%), sodium dodecyl benzene sulfonate 0.4 parts, n-octyl mercaptan 0.05 parts, trisodium nitrilotriacetate 0.1 parts, ferrous chloride 0.001 parts, sodium hyposulfite 0.2 parts, deionized water 15 parts were added into the reaction kettle, stirred and mixed uniformly, heated to 75℃;

[0073] 2) continuous drop polymerization stage

[0074] Maintain 75 ℃ constant temperature, respectively, to the reaction system uniform speed drop 30 parts of the copolymer mixture (styrene 20 parts, acrylonitrile 10 parts), 0.2 parts of tert-butyl hydroperoxide, 0.6 parts of ethylene glycol diacrylate, start the polymerization reaction; wherein the copolymer and tert-butyl hydroperoxide 2h drop is completed, ethylene glycol diacrylate 1h drop is completed; drop is completed after constant temperature reaction, sampling monitoring system copolymer conversion rate is 97.83% when stop reaction, the polymerization reaction time is 4h (crosslinking agent in the polymerization reaction of the first 1 / 4 period of time drop is completed), cooling get ASA resin with grafting latex.

[0075] Example 3

[0076] Preparation of high impact high weathering ASA resin with grafting latex:

[0077] 1) bottom stage

[0078] The polybutyl acrylate latex 118 parts (dry base 50 parts, particle size 427nm, solid content 43.2%), sodium dodecyl naphthalene sulfonate 3 parts, n-dodecyl mercaptan 0.5 parts, sodium hexametaphosphate 0.6 parts, sodium bisulfite 0.007 parts, erythorbic acid 0.2 parts, deionized water 100 parts were added into the reaction kettle, stirred and mixed uniformly, heated to 55℃;

[0079] 2) Continuous dropwise addition polymerization stage

[0080] Maintain 55°C constant temperature, respectively, to the reaction system uniform speed drop 70 parts of the copolymer mixture (styrene 50 parts, acrylonitrile 20 parts), 0.5 parts of dicumyl peroxide, 1 parts of 1, 4-butanediol dimethyl acrylate, start polymerization reaction; wherein the copolymer and dicumyl peroxide 3h dropwise complete, 1, 4-butanediol dimethyl acrylate 1.5h dropwise complete; dropwise complete constant temperature reaction, sampling monitoring system copolymer conversion rate 97.7% when stopped reaction, the polymerization reaction time is 5h (crosslinking agent in the polymerization reaction of the first 1 / 3.3 period complete dropwise charging), cooling get ASA resin grafting latex.

[0081] Example 4

[0082] Preparation of high impact high weathering ASA resin grafting latex:

[0083] 1) Paving stage

[0084] The polybutyl acrylate latex 118 parts (dry base 50 parts, particle size 427nm, solid content 43.2%), sodium dodecyl sulfate 1.5 parts, tertiary dodecyl mercaptan 0.3 parts, ethylenediaminetetraacetic acid disodium 0.3 parts, ferrous sulfate 0.001 parts, glucose 0.2 parts, deionized water 50 parts into the reaction kettle, stirring and mixing uniformly, heated to 65°C;

[0085] 2) Continuous dropwise addition polymerization stage

[0086] Maintain 65°C constant temperature, respectively, to the reaction system uniform speed drop 60 parts of the copolymer mixture (styrene 40 parts, acrylonitrile 20 parts), 0.3 parts of hydrogen peroxide cumene, 1 parts of ethylene glycol dimethyl acrylate, start polymerization reaction; wherein the copolymer and hydrogen peroxide cumene 3h dropwise complete, ethylene glycol dimethyl acrylate 1h dropwise complete; dropwise complete constant temperature reaction, sampling monitoring system copolymer conversion rate 97.5% when stopped reaction, the polymerization reaction time is 5h (crosslinking agent in the polymerization reaction of the first 1 / 5 period complete dropwise charging), cooling get ASA resin grafting latex.

[0087] Example 5

[0088] Preparation of high impact high weathering ASA resin grafting latex:

[0089] 1) Paving stage

[0090] Polybutyl acrylate latex 118 parts (dry base 50 parts, particle size 427 nm, solid content 43.2%), sodium dodecyl sulfate 0.5 parts, tertiary dodecyl mercaptan 0.2 parts, ethylenediaminetetraacetic acid disodium 0.1 parts, ferrous sulfate 0.001 parts, sodium formaldehyde sulfoxylate 0.1 parts, deionized water 27 parts were added to the reaction kettle, stirred and mixed uniformly, heated to 70°C;

[0091] 2) Continuous dropwise addition of polymerization stage

[0092] The temperature was maintained at 70°C, and 30 parts of a comonomer mixture (20 parts of α-methylstyrene, 10 parts of acrylonitrile), 0.2 parts of cumene hydroperoxide, and 0.3 parts of 1,6-hexanediol dimethacrylate were added to the reaction system at a uniform rate, and the polymerization reaction was started; the comonomer and cumene hydroperoxide were added dropwise for 4 h, and the 1,6-hexanediol dimethacrylate was added dropwise for 1 h; after the dropwise addition was completed, the temperature was maintained, and the reaction was stopped when the comonomer conversion rate of the system was 97.9% as monitored by sampling; the total polymerization reaction time was 5 h (the crosslinking agent was added dropwise and charged in the first 1 / 5 of the polymerization reaction time), and the ASA resin grafting latex was obtained after cooling.

[0093] Comparative Example 1

[0094] ASA resin grafting latex was prepared according to the method of Example 1, except that the divinylbenzene, the comonomer, and the cumene hydroperoxide were all added dropwise simultaneously for 3 h, and the other operations and conditions were unchanged; the total polymerization reaction time was 5 h (the crosslinking agent was added dropwise and charged in the first 3 / 5 of the polymerization reaction time).

[0095] Comparative Example 2

[0096] ASA resin grafting latex was prepared according to the method of Example 2, except that the ethylene glycol diacrylate, the comonomer, and the tert-butyl hydroperoxide were all added dropwise simultaneously for 2 h, and the other operations and conditions were unchanged; the total polymerization reaction time was 4 h (the crosslinking agent was added dropwise and charged in the first 1 / 2 of the polymerization reaction time).

[0097] Comparative Example 3

[0098] ASA resin grafting latex was prepared according to the method of Example 3, except that the 1,4-butanediol dimethacrylate comonomer and the dicumyl peroxide were all added dropwise simultaneously for 1.7 h, and the other operations and conditions were unchanged; the total polymerization reaction time was 5 h (the crosslinking agent was added dropwise and charged in the first 1 / 2.9 of the polymerization reaction time).

[0099] The particle size and solid content of the ASA resin grafting latex prepared in each example and comparative example were tested (see Table 1), and ASA resin was prepared according to the following method using the above ASA resin grafting latex as the raw material, respectively.

[0100] (1) Coagulation / drying: 100 parts of ASA grafting latex emulsion was added into a reactor, heated to 90°C, 4 parts of MgSO4 and 40 parts of deionized water were gradually added thereto, and uniformly stirred for 1 h. The obtained coagulation emulsion was filtered with 200 mesh stainless steel filter cloth to obtain wet ASA glue powder, which was dried in a fluidized bed dryer at 65°C for 1 h to obtain ASA glue powder with water content <1 wt%;

[0101] (2) Blending: a twin-screw extruder was used to blend SAN resin (80HF) with the above ASA glue powder at a mass ratio of 60:40 at 240°C, and then cooled and granulated to obtain the ASA resin.

[0102] The impact strength and weather resistance of each ASA resin were tested, and the test results are shown in Table 1.

[0103] Table 1, performance test results

[0104]

[0105] Comparative example test data and attached Figure 1 、 2 The electron microscope photos of Comparative Example and Example show that the integrity of the dispersed phase rubber particles of the ASA resin prepared by the present application is maintained, and there is no large-scale damage, so that the impact resistance of the resin is significantly improved while ensuring high weather resistance.

Claims

1. A method for preparing a graft latex for a high-impact high-weathering ASA resin, characterized by, The polybutyl acrylate latex is mixed with a comonomer under the condition of a crosslinking agent and an initiator to perform a polymerization reaction, thereby obtaining an ASA grafted latex; The crosslinking agent is added dropwise in the first 1 / 3 period of the polymerization reaction.

2. The production method according to claim 1, characterized by, The crosslinking agent is added dropwise in the first 1 / 5-1 / 3 period of the polymerization reaction.

3. The method of claim 1, wherein step It comprises: 1) bottoming stage: the polybutyl acrylate latex, and optionally emulsifier, chain transfer agent, complexing agent, reducing agent, reducing agent, water are added into the reactor and stirred uniformly, and then heated to the polymerization temperature; 2) continuous dropwise polymerization stage: the comonomer, initiator and crosslinking agent are added dropwise into the reactor to perform a polymerization reaction, wherein the crosslinking agent is added in the first 1 / 3 period of the polymerization reaction, and the ASA resin grafted latex is prepared after the reaction is completed.

4. The production method according to claim 3, characterized by, In step 1), the polymerization temperature is 40-90℃; and / or In step 2), the dropwise adding time of the comonomer and initiator is 1-5h; and / or In step 2), the polymerization time is 1-5h.

5. The production method according to claim 4, characterized by, In step 1), the polymerization temperature is 50-80℃.

6. The preparation method according to claim 4, characterized in that, In step 2), the polymerization time is 2-4h.

7. The preparation method according to claim 4, characterized in that, In step 2), the polymerization reaction is considered to be completed when the total conversion rate of the comonomer is >95%.

8. The preparation method according to claim 3, characterized in that, In step 1), the polybutyl acrylate latex has a particle size of 400-600nm and a solid content of 30-50wt%; and / or In step 2), the comonomer is selected from a mixture of vinyl cyanide and aromatic vinyl compound; and / or In step 2), the initiator is selected from C3-C18 organic peroxide; and / or In step 2), the crosslinking agent is selected from one or more of aromatic compounds having two vinyl groups, acrylate compounds.

9. The production method according to claim 8, characterized by, The vinyl cyanide is acrylonitrile, and the aromatic vinyl compound is styrene.

10. The preparation method according to claim 8, characterized in that, In the mixture, the mass ratio of the vinyl cyanide to the aromatic vinyl compound is 1:2-5.

11. The preparation method according to claim 8, characterized in that, The initiator is selected from one or more of dicumyl peroxide, cumene hydroperoxide, and tert-butyl hydroperoxide.

12. The preparation method according to claim 8, characterized in that, The crosslinking agent is selected from one or more of divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, and 1,6-hexanediol dimethacrylate.

13. The preparation method according to claim 3, characterized in that, In step 1), the emulsifier is selected from one or more of alkyl sulfate, alkyl sulfonate, alkyl benzene sulfonate, and alkyl naphthalene sulfonate; and / or The chain transfer agent is selected from one or more of n-dodecyl mercaptan, tert-dodecyl mercaptan, n-octyl mercaptan, and iso-octyl mercaptan; and / or The complexing agent is selected from one or more of trisodium nitrilotriacetate, disodium ethylenediaminetetraacetate, tetrasodium ethylenediaminetetraacetate, sodium pyrophosphate, and sodium hexametaphosphate; and / or The reducing agent is selected from one or more of ferrous sulfate, ferrous chloride, and sodium bisulfite; and / or The reducing agent is selected from one or more of sodium dithionite, sodium formaldehyde sulfoxylate, erythorbic acid, glucose, and lactose.

14. The method of claim 3, wherein, The amount of the comonomer is 50-200% of the dry weight of the polybutyl acrylate latex.

15. The preparation method according to claim 3, characterized in that, The mass ratio of the comonomer, crosslinking agent, initiator, emulsifier, chain transfer agent, complexing agent, reducing agent, reducing aid, water is 100: (0.5-5): (0.1-1): (0-5): (0-1): (0-1): (0-0.01): (0-1): (0-200).

16. The method of claim 15, wherein, The mass ratio of the comonomer, crosslinking agent, initiator, emulsifier, chain transfer agent, complexing agent, reducing agent, reducing aid, water is 100: (0.5-5): (0.1-1): (1-5): (0.1-1): (0.1-1): (0.001-0.01): (0.1-1): (80-200).

17. A graft latex for high impact high weathering ASA resin prepared by the method of any one of claims 1-16.

18. Use of the emulsion for high impact high weathering ASA resin prepared by the method of any one of claims 1-16 in the preparation of an ASA resin.

19. A high impact high weathering ASA resin characterized in that, The graft latex for high impact high weathering ASA resin prepared by the method of any one of claims 1-16 is coagulated to break the emulsion to prepare an ASA powder, which is then blended and extruded with a SAN resin to prepare.

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