CN114230963B - Oil-resistant high-impact ABS/PBT composite material and preparation method thereof - Google Patents

Abstract

An oil-resistant high-impact ABS/PBT composite material comprises the following raw materials; ABS, modified PBT, a microencapsulated flame retardant, a compatilizer and an antioxidant, wherein the modified PBT is prepared by carrying out esterification polycondensation reaction on terephthalic acid, alcohol-terminated hydroxyl fluorosilicone oil and butanediol. The composite material comprises PBT prepared by copolymerization modification of fluorosilicone oil, and as fluorocarbon bond energy is large, bond length is short, carbon atoms are protected by fluorine atoms, other atoms are not easy to invade, carbon chains become firmer, and the modified PBT has higher heat resistance and better oil resistance; the composite material is also provided with a polymer microencapsulated flame retardant, so that the composite material is endowed with good flame retardance, and the surface of the composite material is coated with a polymer with good interface binding capacity with ABS and PBT, so that the composite material is uniformly dispersed and has a reinforcing effect, and the microencapsulated flame retardant has the effect of improving the thermal deformation temperature of the composite material by synergistically modifying PBT.

Description

Oil-resistant high-impact ABS/PBT composite material and preparation method thereof

Technical Field

The invention belongs to the technical field of ABS (acrylonitrile butadiene styrene) alloys, and particularly relates to an oil-resistant high-impact-resistance ABS composite material and a preparation method thereof.

Background

In recent years, under the influence of resource and environmental problems, new energy automobiles gradually replace traditional fuel automobiles, and high-energy storage new energy storage batteries become a research and development hotspot, wherein the research and development of storage battery shells with good mechanical properties, good heat resistance and high oil resistance is the primary technical problem to be solved in the research and development process of storage batteries. Acrylonitrile-butadiene-styrene (ABS) is a nonpolar thermoplastic elastomer with good heat resistance, high surface hardness, high chemical stability, and excellent low-temperature impact resistance, and is also the first choice material for battery case materials of storage batteries, but its brittle, poor weather resistance, low thermal deformation temperature, and poor oil resistance properties limit its application in this field to some extent, and further improvement is needed.

Because the ABS alloy has simple preparation process and lower required cost, in order to better meet the market demand, some resins with complementary properties are often added into the ABS to prepare alloy materials, which can effectively improve the defects of the ABS in performance, for example, Chinese patent CN201911408528.1 discloses an ABS/polyester alloy composition and a preparation method thereof, the composition comprises the following components: 30-80 parts of styrene-butadiene-acrylonitrile resin; 5-30 parts of a toughening agent; 10-65 parts of polyester resin; 10-40 parts of degradable polyester resin. According to the invention, the polyester and the degradable polyester are simultaneously introduced into the ABS system, so that the alloy material with high fluidity, ultrahigh toughness and degradable property can be obtained. Patent CN201810146427.0 discloses an ASA/polyester alloy material, a preparation method and application thereof, comprising the following components: 50-80 parts of acrylonitrile-styrene-acrylate resin; 10-65 parts of polyester resin; high damping elastomer: 1.0-15 parts. According to the invention, polyester and high-damping rubber are introduced into an ASA system, so that the prepared ASA/polyester alloy material has a noise reduction effect and excellent environmental stress cracking resistance and light aging resistance. The above techniques are all the improvement of ABS performance by using physical blending alloy technology, and although the mechanical property and weather resistance are improved, the thermal deformation temperature and oil resistance are still poor, and the technique cannot adapt to the possible environments of high temperature, multi-engine oil and the like of the battery case of the storage battery.

Therefore, in summary, there is a need to develop an ABS alloy material with good toughness, high heat distortion temperature and oil resistance.

Disclosure of Invention

The invention aims to solve the technical problems and provides an oil-resistant high-impact ABS composite material and a preparation method thereof, wherein the composite material comprises PBT prepared by copolymerization modification of fluorosilicone oil, and as fluorocarbon bond energy is large, bond length is short, carbon atoms are protected by fluorine atoms, other atoms are not easy to invade, carbon chains are firmer, and the modified PBT has higher heat resistance and better oil resistance; the composite material is also provided with a polymer microencapsulated flame retardant, which not only endows the composite material with good flame retardance, but also has the function of enhancing because the surface is coated with a polymer with better interface binding capacity with ABS and PBT, and the dispersion is uniform.

In order to achieve the purpose, the invention adopts the following specific technical scheme:

an oil-resistant high-impact ABS/PBT composite material comprises the following raw materials; ABS, modified PBT, a microencapsulated flame retardant, a compatilizer and an antioxidant, wherein the modified PBT is prepared by carrying out esterification polycondensation reaction on terephthalic acid, alcohol-terminated hydroxyl fluorosilicone oil and butanediol.

An oil-resistant high-impact ABS composite material comprises the following raw materials in parts by weight: 30-60 parts of ABS, 30-60 parts of modified PBT, 15-25 parts of microencapsulated flame retardant, 1-10 parts of compatilizer and 0.5-1 part of antioxidant, wherein the weight ratio of the terephthalic acid, the alcohol-terminated hydroxyl fluorosilicone oil and the butanediol is 32:5-10: 20-24.

The structural formula of the alcohol hydroxyl terminated fluorosilicone oil is as follows:

wherein n is an integer of 3 to 9, R₁Is C1-C5 alkylene, the R₂、R₃Independently at least one of C1-C3 alkyl groups and C1-C4 hydroxyl-terminated alkyl siloxane groups.

Preferably, said R is₂、R₃Independently is a C1-C3 alkyl group.

The alcohol hydroxyl terminated fluorosilicone oil is prepared by firstly carrying out alkoxy hydrolysis reaction on halogenated siloxane under an acidic condition, condensing a hydrolysate and polymethyl (3,3, 3-trifluoropropyl) siloxane, and carrying out hydrolysis reaction on a halogenated alkane on a condensation product under alkaline catalysis.

The molar ratio of the polymethyl (3,3, 3-trifluoropropyl) siloxane to the halogenated siloxane is 1: 2.10-2.25.

The structural formula of the halogenated siloxane is as follows:

the R is₂、R₃The same or different, independently C1-C3 alkyl; the R is₄Is C1-C4 terminal alkyl alcohol.

Polymethyl (3,3, 3-trifluoropropyl) siloxane is a silicon hydroxyl terminated oligomer, has the characteristics of high and low temperature resistance and fuel oil resistance of common fluorine-silicon polymers, has great chemical activity, and can generate condensation reaction with other silicon hydroxyl substances to generate polysiloxane.

The halogenated siloxane is selected from at least one of chloromethyl (dimethyl) methoxy silane, chloromethyl ethoxy dimethyl silane, chloromethyl dimethyl isopropoxy phenyl silane, chloromethyl (dimethyl) tert-butyl oxy silane, chloromethyl (dimethyl) isobutyl oxy silane, chloromethyl (dimethyl) butyl oxy silane, chloromethyl (dimethyl) propoxy silane, chloromethyl (dimethyl) isopentoxy silane and chloromethyl (dimethyl) pentoxy silane.

The alcohol hydroxyl-terminated fluorosilicone oil is prepared by a preparation method comprising the following steps:

1) hydrolytic condensation reaction

Under the condition of room temperature acid catalysis, mixing halogenated siloxane and water, hydrolyzing, adding polymethyl (3,3, 3-trifluoropropyl) siloxane when a hydrolysis reaction system is changed into a transparent phase from two phases (visible layering by naked eyes), stirring uniformly, heating for continuous reaction, and after the reaction is stopped, placing the mixture under the condition of high temperature and negative pressure to remove impurities to obtain a viscous substance;

2) alkyl halide hydrolysis reaction

Adding alkali liquor and zeolite into the substance obtained in the step 1), heating to a boiling reflux state for reaction, cooling, adding acid liquor for neutralization to neutrality, repeatedly washing with water and separating liquid until no chloride ions exist in the mixture, and carrying out reduced pressure distillation to obtain viscous alcohol hydroxyl fluorosilicone oil.

Step 1), acid catalysis is to use 30-40 wt% hydrochloric acid solution to make the pH of a hydrolysis reaction system be 2-4, and the molar ratio of the halogenated siloxane to water is 1: 0.3-0.5; the temperature is raised to 50-80 ℃, and the reaction time is 1-5 h; the high temperature is 100 ℃ and 150 ℃, and the negative pressure is 0.05-0.1 MPa.

Step 2), the concentration of the alkali liquor is 5-15 wt%, the volume of the alkali liquor is 1/4-3/4 of the volume of the hydrolyzed substance, the type of the alkali liquor is not particularly limited, and the alkali liquor comprises at least one of sodium hydroxide solution and potassium hydroxide solution; the reaction time is 30-120 min.

The preparation method of the modified PBT comprises the following steps:

esterification reaction of T1: under the inert atmosphere, adding terephthalic acid, alcohol-terminated hydroxyl fluorosilicone oil, butanediol and a catalyst into a reaction kettle, uniformly mixing, keeping stirring, heating for the first time, reacting at normal pressure, then reducing pressure, heating for the second time, continuing the reaction, and collecting distillate to obtain an esterified substance for later use;

t2 polycondensation reaction: and (3) depressurizing the reaction system of the step T1 for the first time, keeping constant temperature and stirring, carrying out pre-polycondensation on the esterified substance obtained in the step T1, depressurizing again for polycondensation, collecting distillate, and naturally cooling to room temperature to obtain the modified PBT.

In the step T1, the catalyst is Ti catalyst, specifically at least one of tetraisopropyl titanate and tetrabutyl titanate, and the dosage of the catalyst is 0.04-0.07 wt% of terephthalic acid; the first temperature rise is up to 230 ℃ and the normal pressure reaction time is 50-150min, the pressure reduction is down to 0.3-0.5atm, the second temperature rise is up to 240 ℃ and 260 ℃ and the second temperature rise reaction time is 30-50 min.

The first decompression of step T2 is reduced to 0.01-0.03atm, the pre-polycondensation time is 20-50min, the second decompression is reduced to 0.005-0.001atm, and the polycondensation reaction time is 1-5 h.

The compatilizer is at least one selected from styrene-maleic anhydride copolymer (SMA), styrene-acrylonitrile-glycidyl methacrylate copolymer (SAG) and methyl methacrylate-butadiene-styrene terpolymer (MBS).

The antioxidant comprises at least one of hindered phenol, phosphite ester and thiodipropionate antioxidant.

The wall material of the microencapsulated flame retardant is a polymer with good compatibility with ABS and PBT, such as at least one of polystyrene, polystyrene derivatives, polyethylene derivatives, polybutadiene and polybutadiene derivatives; the core material is a flame retardant, and in a specific embodiment of the invention, the flame retardant comprises at least one of aluminum hydroxide and magnesium hydroxide, and the particle size is 100-500 nm.

The mass ratio of the core material to the wall material of the microencapsulated flame retardant is 1: 0.9-1.4.

Microencapsulation of the flame retardant aims at improving the compatibility of the flame retardant and resin, so that the flame retardant is dispersed in the resin more uniformly and is not easy to precipitate, and a better flame retardant effect is obtained.

Preferably, the wall material polymer is a polystyrene derivative, and the polystyrene derivative comprises the following monomers of styrene, ethylene glycol dimethacrylate and maleimide.

The mol ratio of the styrene to the maleimide to the ethylene glycol dimethacrylate is 4:1-2: 0.1-0.3.

Further, when the wall material polymer is a copolymer of styrene, ethylene glycol dimethacrylate and maleimide, the preparation method of the microencapsulated flame retardant comprises the following steps:

1) preparing an aqueous phase: adding water, a flame retardant and a dispersing agent into a container, and stirring at constant temperature until the mixture is uniform;

2) preparing an oil phase: adding styrene, glycidyl methacrylate, maleimide and an initiator into a reaction kettle, and reacting at constant temperature;

3) and adding the water phase into the oil phase, uniformly stirring, heating for reaction, stopping heating, naturally cooling to room temperature under the stirring condition, performing suction filtration, washing, drying and screening to obtain the microencapsulated flame retardant.

The dispersing agent in the step 1) comprises at least one of polyvinyl alcohol and polyvinylpyrrolidone; the constant temperature is 30-60 ℃.

The initiator in step 2) is commonly used in the field, and includes but is not limited to azobisisobutyronitrile, benzoyl peroxide; the constant temperature reaction temperature is 30-80 ℃, and the reaction time is 10-40 min.

Step 3), heating to 60-100 ℃, wherein the reaction time is 1-5 h; the sieve is 800-1250 mesh sieve.

The invention also provides a preparation method of the oil-resistant high-impact ABS composite material, which comprises the following steps:

and uniformly mixing ABS, modified PBT, the microencapsulated flame retardant, the compatilizer and the antioxidant, and adding the mixture into a feeder of a double-screw extruder for extrusion granulation to obtain the ABS composite material.

The length-diameter ratio of the double-screw extruder is 35-44:1, the screw rotation speed is 80-1000r/min, the extrusion temperature is 180-.

Compared with the prior art, the invention has the beneficial effects that:

the composite material comprises PBT prepared by copolymerization modification of fluorosilicone oil, and as fluorocarbon bond energy is large, bond length is short, carbon atoms are protected by fluorine atoms, other atoms are not easy to invade, carbon chains become firmer, and the modified PBT has higher heat resistance and better oil resistance; the composite material is also provided with a polymer microencapsulated flame retardant, which not only endows the composite material with good flame retardance, but also has the function of enhancing because the surface is coated with a polymer with better interface binding capacity with ABS and PBT, and the dispersion is uniform.

The invention unexpectedly discovers that the microencapsulated flame retardant has the effect of improving the heat distortion temperature of the composite material by synergistically modifying PBT.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to the descriptions in the following. Unless otherwise specified, "parts" in the examples of the present invention are parts by weight. All reagents used are commercially available in the art.

Polymethyl (3,3, 3-trifluoropropyl) siloxane was purchased from Shanghai Michelle chemical technology, Inc. with a number average molecular weight of 1200.

Aluminum hydroxide was purchased from tencapone new materials, llc of hangzhou.

ABS was purchased from landlocked petrochemical company.

Preparation example a preparation of microencapsulated flame retardant

Preparation a1

1) Preparing an aqueous phase: adding 650g of water, 60g of aluminum hydroxide with the average particle size of 190nm and 1.3g of polyvinyl alcohol into a container, and stirring at the constant temperature of 60 ℃ until the mixture is uniform;

2) preparing an oil phase: adding 0.4mol of styrene, 0.02mol of ethylene glycol dimethacrylate, 0.2mol of maleimide and 0.1g of benzoyl peroxide into a reaction kettle, and reacting for 30min at the constant temperature of 60 ℃;

3) and adding the water phase into the oil phase, uniformly stirring, heating to 80 ℃, reacting for 3 hours to obtain milky white liquid, stopping heating, naturally cooling to room temperature under the condition of stirring, carrying out suction filtration, washing, drying, sieving with an 800-mesh sieve, and thus obtaining the microencapsulated flame retardant.

Preparation a2

The other conditions and operations are the same as in preparation a1, except that no ethylene glycol dimethacrylate was added in step 2).

Preparation a3

The other conditions and operations were the same as in preparation a1, except that no maleimide was added in step 2).

Preparation example b preparation of a modified PBT

Preparation b1

Firstly, preparing alcohol-terminated hydroxyl fluorosilicone oil

1) Hydrolytic condensation reaction

Under the condition of stirring at room temperature, dripping 35 wt% hydrochloric acid solution into a mixture of 2.1mol of chloromethyl (dimethyl) methoxysilane and 1.05mol of water, wherein the pH value of a hydrolysis reaction system is 3.5 within 18min, the mixed system is changed into a transparent phase from two phases when the hydrolysis reaction system is carried out for 78min, adding 1mol of polymethyl (3,3, 3-trifluoropropyl) siloxane, stirring uniformly, heating to 60 ℃, continuing to react for 3h, stopping the reaction, and then placing the mixture at the high temperature of 110 ℃ under the condition of negative pressure of 0.06MPa to remove impurities to obtain a viscous substance;

2) alkyl halide hydrolysis reaction

Adding 150ml of 10 wt% sodium hydroxide solution and zeolite into 200ml of viscous substance prepared according to the step 1), heating to a boiling reflux state, reacting for 60min, cooling to room temperature, dropwise adding 10 wt% hydrochloric acid solution for neutralizing to be neutral, washing and separating by deionized water, repeating the steps for 4 times, detecting that no chlorine ion exists in the mixture by using silver nitrate solution, and distilling under reduced pressure to obtain viscous alcohol-terminated hydroxyl fluorosilicone oil.

Mw of 1390 was determined by GPC (toluene as the mobile phase, flow rate 1.0ml/min, styrene as standard).

Secondly, preparing the modified PBT

Esterification reaction of T1: under the nitrogen atmosphere, adding 32 parts of terephthalic acid, 10 parts of the prepared alcohol-terminated hydroxyl fluorosilicone oil, 20 parts of butanediol and 0.016 part of tetraisopropyl titanate into a reaction kettle, uniformly mixing, keeping stirring, firstly heating to 220 ℃, reacting for 60min under normal pressure, then reducing the pressure to 0.03atm, secondly heating to 240 ℃, continuing to react for 50min, and collecting distillate to obtain an esterified substance for later use;

t2 polycondensation reaction: and (3) firstly reducing the pressure of the reaction system in the step T1 to 0.01atm, keeping constant-temperature stirring, carrying out pre-polycondensation on the esterified substance obtained in the step T1 for 30min, reducing the pressure to 0.002atm again, carrying out polycondensation reaction for 3h, collecting distillate, and naturally cooling to room temperature to obtain the modified PBT.

Preparation b2

The procedure was as in example 1 except that chloromethyl (dimethyl) methoxysilane was used in an amount of 2.25mol and water was used in an amount of 1.125mol in the first step of the preparation of fluorosilicone oil.

Mw was 1382 by GPC (toluene as the mobile phase, flow rate 1.0ml/min, styrene as a standard).

Preparation b3

The rest is the same as the example 1, except that the amount of the alcohol terminated hydroxy fluorosilicone oil used in the second step, step T1 of preparing the modified PBT is 5 parts.

Preparation b4

The process is otherwise the same as in example 1, except that in step two, step T1 of the modified PBT, 24 parts of butanediol are used.

Preparation b5

The rest is the same as the example 1, except that the amount of the alcohol terminated hydroxy fluorosilicone oil used in the second step, step T1 of preparing the modified PBT is 3 parts.

Preparation b6

The rest is the same as the example 1, except that the amount of the alcohol terminated hydroxy fluorosilicone oil used in the second step, step T1 of preparing the modified PBT is 15 parts.

Comparative preparation b1

The process is the same as example 1 except that no alcohol-terminated hydroxyfluorosilicone oil is used in step two, step T1 for preparing the modified PBT, and the amount of butanediol used is 22 parts.

Preparation of ABS composite material

Application example 1

60 parts of ABS, 60 parts of modified PBT prepared in preparation example b1, 25 parts of microencapsulated flame retardant prepared in preparation example a1, 2 parts of styrene-maleic anhydride copolymer, 2 parts of styrene-acrylonitrile-glycidyl methacrylate copolymer, 1 part of methyl methacrylate-butadiene-styrene terpolymer and 1 part of antioxidant CHEMNOX1010 are uniformly mixed in a high-speed mixer, added into a double screw with the length-diameter ratio of 44:1, and extruded and granulated at the rotating speed of 100r/min, wherein the extrusion temperature is 190 ℃, 210 ℃, 220 ℃, 210 ℃ and 200 ℃.

Application example 2

The rest is the same as the application example 1, except that the amount of the modified PBT is 30 parts.

Application example 3

The rest of the process was the same as in application example 1, except that the amount of ABS was 30 parts.

Application example 4

The rest of the test piece was the same as in application example 1, except that the amount of the microencapsulated flame retardant was 15 parts.

Application examples 5 to 9, comparative application example 1

The rest is the same as in application example 1, except that the modified PBT used corresponds to that of preparation b2-6 and comparative preparation b1, respectively.

Application examples 10 to 11

The rest was the same as in application example 1, except that the microencapsulated flame retardant was prepared in preparation example a 2-preparation example a3

Comparative application example 2

The rest was the same as in application example 1 except that the flame retardant used was not microencapsulated.

The ABS composite material prepared by the application example and the comparative application example is subjected to the following performance tests:

heat distortion temperature: the test was carried out according to the standard ASTM D1525, equipment Vicat temperature tester, load 5kg, heating rate 50 ℃/h.

Notched impact strength: the test was performed with reference to the standard GB/T12672-.

Oil resistance: coating Mobil brake fluid DOT4 on the surface of a tensile sample strip, fixing the tensile sample strip on an arc-shaped die with an angle of 76 degrees by using three-point rotating screws, wherein the size of the arc-shaped die is 16.0cm multiplied by 3.8cm multiplied by 7.0cm, then putting the sample strip die into an oven together, and observing the cracking condition of the tensile sample strip at the temperature of 60 ℃, wherein the size of the tensile sample strip is prepared according to the standard GB/T12672-2009.

Flame retardant property: with reference to the Standard GB/T2508-1996 test methods for Plastic burning Performance-horizontal and vertical, the dimensions of the specimen are 125mm × 12.5mm × 3.2 mm.

TABLE 1

As can be seen from the experimental results in the table above: the PBT prepared by copolymerization modification of the alcohol-terminated hydroxyl fluorosilicone oil and blending with the ABS has good heat resistance and better oil resistance; the flame retardant after the polymer microencapsulation not only can endow the composite material with good flame retardance, but also has the function of enhancing because the surface is coated with the polymer with better interface binding capacity with ABS and PBT, and the dispersion is uniform.

The comparison of the application example and the comparative application example shows that the microencapsulated flame retardant has the effect of synergistically modifying the PBT to improve the thermal deformation temperature of the composite material, and the microencapsulated flame retardant is supposed to play the role of a nucleating agent in a molten state, so that the crystallization performance of the composite material can be improved, and the high-temperature resistance of the composite material can be further improved.

The above detailed description is specific to one possible embodiment of the present invention, and the embodiment is not intended to limit the scope of the present invention, and all equivalent implementations or modifications without departing from the scope of the present invention should be included in the technical scope of the present invention.

Claims (8)

1. The oil-resistant high-impact ABS/PBT composite material is characterized by comprising the following raw materials in parts by weight: 30-60 parts of ABS, 30-60 parts of modified PBT, 15-25 parts of microencapsulated flame retardant, 1-10 parts of compatilizer and 0.5-1 part of antioxidant, wherein the modified PBT is prepared by the polycondensation reaction of terephthalic acid, alcohol-terminated hydroxyl fluorosilicone oil and butanediol; the weight ratio of the terephthalic acid to the alcohol-terminated hydroxyl fluorosilicone oil to the butanediol is 32:5-10: 20-24;

the structural formula of the alcohol hydroxyl terminated fluorosilicone oil is as follows:

wherein n is an integer of 3 to 9, R₁Is C1-C5 alkylene, R₂、R₃Independently is a C1-C3 alkyl group;

the microencapsulated flame retardant comprises a wall material and a core material, wherein the wall material is a copolymer of styrene, ethylene glycol dimethacrylate and maleimide, the core material is a flame retardant, and the mass ratio of the core material to the wall material is 1: 0.9-1.4.

2. The composite material of claim 1, wherein the alcoholic hydroxyl group-terminated fluorosilicone oil is prepared by firstly carrying out alkoxy hydrolysis reaction on halogenated siloxane under an acidic condition, condensing a hydrolysate with polymethyl (3,3, 3-trifluoropropyl) siloxane, and then carrying out hydrolysis reaction on alkyl halide on the condensation product under alkaline catalysis; the molar ratio of the polymethyl (3,3, 3-trifluoropropyl) siloxane to the halogenated siloxane is 1: 2.10-2.25.

3. The composite material of claim 2, wherein the halosiloxane has the formula:

the R is₂、R₃The same or different, independently C1-C3 alkyl; the R is₄Is C1-C4 terminal alkyl alcohol.

4. The composite material of claim 2, wherein the halogenated siloxane is at least one member selected from the group consisting of chloromethyldimethylmethoxysilane, chloromethylethoxydimethylsilane, chloromethyldimethylisopropoxyphenylsilane, chloromethyldimethyl-t-butyloxysilane, chloromethyldimethyl-isobutyloxysilane, chloromethyldimethyl-propoxysilane, chloromethyldimethyl-isopentoxysilane, and chloromethyldimethyl-pentyloxysilane.

5. The composite material of claim 1, wherein the alcohol hydroxyl terminated fluorosilicone oil is prepared by a preparation method comprising the following steps:

1) hydrolytic condensation reaction

Mixing halogenated siloxane and water under the condition of room temperature acid catalysis, hydrolyzing, adding polymethyl (3,3, 3-trifluoropropyl) siloxane when a hydrolysis reaction system is changed from two phases into a transparent phase, stirring uniformly, heating to continue reacting, and placing the mixture under the condition of high temperature and negative pressure after the reaction is stopped to remove impurities to obtain a viscous substance;

2) alkyl halide hydrolysis reaction

Adding alkali liquor and zeolite into the substance obtained in the step 1), heating to a boiling reflux state for reaction, cooling, adding acid liquor for neutralization to neutrality, repeatedly washing with water and separating liquid until no chloride ions exist in the mixture, and carrying out reduced pressure distillation to obtain viscous alcohol hydroxyl fluorosilicone oil.

6. The composite material of claim 1, wherein the preparation method of the modified PBT comprises the following steps:

esterification reaction of T1: under the inert atmosphere, adding terephthalic acid, alcohol-terminated hydroxyl fluorosilicone oil, butanediol and a catalyst into a reaction kettle, uniformly mixing, keeping stirring, heating for the first time, reacting at normal pressure, then reducing pressure, heating for the second time, continuing the reaction, and collecting distillate to obtain an esterified substance for later use;

t2 polycondensation reaction: and (3) depressurizing the reaction system of the step T1 for the first time, keeping constant temperature and stirring, carrying out pre-polycondensation on the esterified substance obtained in the step T1, depressurizing again for polycondensation, collecting distillate, and naturally cooling to room temperature to obtain the modified PBT.

7. The composite material of claim 1, wherein the styrene, maleimide, and ethylene glycol dimethacrylate are present in a molar ratio of from 4:1 to 2:0.1 to 0.3.

8. A preparation method of the oil-resistant high-impact ABS/PBT composite material of any one of claims 1-7, which comprises the following steps:

and uniformly mixing ABS, modified PBT, the microencapsulated flame retardant, the compatilizer and the antioxidant, and adding the mixture into a feeder of a double-screw extruder for extrusion granulation to obtain the ABS composite material.