阅读说明：本技术 一种sebs/at复合增韧剂及其制备方法、及高性能pet/pa6发泡材料 (SEBS/AT composite toughening agent, preparation method thereof and high-performance PET/PA6 foam material ) 是由 何顺伦 苗宗信 于 2021-08-06 设计创作，主要内容包括：本发明提供一种SEBS/AT复合增韧剂及其制备方法、及高性能PET/PA6发泡材料,所述SEBS/AT复合增韧剂的制备方法具体包括：在搅拌状态下对凹凸棒土(AT)进行干燥、分散至纳米态后,继续搅拌并向干燥的AT中加入偶联剂溶液并将偶联剂溶液和AT均匀混合进行偶联反应,将产物进行干燥除去溶剂,得到纳米级的活性AT,然后将SEBS、活性AT、引发剂和抗氧剂混合均匀,放入单螺杆挤出机挤出造粒得到具有核壳机构的,核层为活性AT,中间层为偶联剂,壳层为SEBS的具有多层结构的SEBS/AT复合增韧剂；将通过上述方法制备的SEBS/AT复合增韧剂加入到PET/PA6发泡材料中,能够在对发泡材料进行增韧的同时避免材料的刚性降低,制备出具有高刚性、高韧性的PET/PA6发泡材料。(The invention provides an SEBS/AT composite toughening agent, a preparation method thereof and a high-performance PET/PA6 foam material, wherein the preparation method of the SEBS/AT composite toughening agent specifically comprises the following steps: drying and dispersing Attapulgite (AT) to a nano state under a stirring state, continuously stirring, adding a coupling agent solution into the dried AT, uniformly mixing the coupling agent solution and the AT for coupling reaction, drying the product to remove a solvent to obtain nano-scale active AT, uniformly mixing SEBS, the active AT, an initiator and an antioxidant, putting the mixture into a single-screw extruder, and extruding and granulating to obtain the SEBS/AT composite toughening agent with a core-shell mechanism, wherein the core layer is the active AT, the middle layer is the coupling agent, and the shell layer is the SEBS; the SEBS/AT composite toughening agent prepared by the method is added into the PET/PA6 foaming material, so that the rigidity of the material can be prevented from being reduced while the foaming material is toughened, and the PET/PA6 foaming material with high rigidity and high toughness is prepared.)

1. The SEBS/AT composite toughening agent is characterized by having a core-shell structure formed by taking active AT as a core and SEBS as a shell, wherein the ratio of the particle size of the SEBS/AT composite toughening agent to the particle size of the active AT is 1000:3-1000: 11.

2. The SEBS/AT composite toughening agent according to claim 1, wherein in the SEBS/AT composite toughening agent, the particle size of the active AT serving as a core structure is 90-110 nm.

3. The SEBS/AT composite toughening agent according to claim 1, wherein the raw material ratio for preparing the SEBS/AT composite toughening agent is as follows:

SEBS：50％-80％；

active AT: 19.7% -49.7%;

initiator: 0.01-0.05 per mill;

antioxidant: 0.2 to 0.3 percent.

4. A preparation method of the SEBS/AT composite toughening agent is characterized by comprising the following steps:

s1, preparing active AT;

s2, preparing the SEBS/AT composite toughening agent with the core-shell structure by taking the active AT as the core and the SEBS as the shell.

5. The preparation method of the SEBS/AT composite toughening agent according to claim 4, wherein in the step S1, the active AT is obtained by the AT through a drying process, a mixing process of mixing with a coupling agent, a coupling reaction process and a solvent removal process.

6. The preparation method of the SEBS/AT composite toughening agent according to claim 5, wherein the drying process is: stirring AT AT 80-100 deg.C for 30-60min AT a first stirring speed;

the first stirring speed is 3000-.

7. The preparation method of the SEBS/AT composite toughening agent according to claim 5, wherein the mixing process is as follows: spraying the coupling agent solution into AT in a form of spray under stirring AT a second stirring speed;

the second stirring speed is 500-600 rpm;

preferably, the coupling agent solution is sprayed into the AT in three portions.

8. The preparation method of the SEBS/AT composite toughening agent according to claim 7, wherein the addition amount of the coupling agent solution is 6-8% of the AT mass;

the coupling agent solution comprises:

a silane coupling agent;

ethanol;

acetic acid aqueous solution;

the volume ratio of the silane coupling agent to the ethanol is 1: 5-8;

the concentration of the acetic acid aqueous solution is 10 percent; the adding mass of the acetic acid water solution is 3-15% of the mass of the ethanol solution of the silane coupling agent.

9. The preparation method of the SEBS/AT composite toughening agent according to claim 5, wherein the coupling reaction process is as follows: continuously stirring at the third stirring speed for 10-30 min;

the third stirring speed was 1800-.

10. The high-performance PET/PA6 foaming material is characterized in that the high-performance PET/PA6 foaming material comprises the following raw materials in percentage by weight:

PET：60％-70％；

PA6：10％-30％；

SEBS/AT composite toughening agent: 5% -8%;

SEBS-g-MA：1％-3％；

the raw materials are mixed and extruded to obtain a toughened PET/PA6 resin material, and the toughened PET/PA6 resin material is foamed to obtain the high-performance PET/PA6 foamed material;

the foaming agent used in the foaming process is liquid CO₂And cyclopentane.

Technical Field

The invention belongs to the technical field of foaming materials, and particularly relates to an SEBS/AT composite toughening agent, a preparation method thereof and a high-performance PET/PA6 foaming material.

Background

The PET foam material is a typical structural foam material, has the highest strength in common plastic foam products under the same condition, has good heat resistance, fatigue resistance and Young modulus, can be recycled, and has good environmental protection performance; however, the PET foam material has serious defects of poor impact resistance and low temperature resistance, low elongation at break, serious post-crystallization phenomenon, and easy warpage of thick products (such as plates), thereby limiting the application of the PET foam material in some structural parts.

PA6 is an important thermoplastic engineering plastic, has high crystallization speed and excellent mechanical property, is sensitive to temperature and moisture, reduces the mechanical property along with the increase of temperature and humidity, and has influenced stability, thereby limiting the application of the PA6 in various fields.

In the prior art, PET and PA6 are blended to make up for respective application defects of PET and PA6 to obtain a composite material with high chemical stability, thermal stability, strength and processability, but PET and PA6 are incompatible crystal/crystal blending systems, the compatibility is poor, a compatilizer needs to be added, and meanwhile, in order to prevent the material from warping in the process of processing and forming, a toughening agent is added into the system to improve the toughness of the material.

The Chinese patent with the application number of CN201110347339.5 discloses a high-toughness low-warpage low-mold-temperature glass fiber reinforced PET/PA6 alloy and a preparation method thereof, wherein the alloy comprises PET, PA6, a toughening agent, a mineral filler, glass fibers, a compatilizer, a composite nucleating agent, a coupling agent and an antioxidant. By adding the compatilizer, the toughening agent and the glass fiber, the material has higher stability, higher impact strength and higher heat distortion temperature, and the warping of the material is reduced; however, the scheme adds more glass fibers and auxiliaries, which may result in that the components cannot be sufficiently and uniformly mixed, and the glass fibers and the inorganic powder can seriously interfere with the foaming process, so that the cell size is increased, and serious merging and perforation phenomena occur, thereby sharply reducing the consistency and uniformity of the performance and the overall performance of the material after molding.

The present invention has been made in view of this situation.

Disclosure of Invention

One of the objectives of the present invention is to provide an SEBS/AT composite toughening agent, which has a core-shell structure with active AT as a core and SEBS as a shell.

Another objective of the present invention is to provide a method for preparing an SEBS/AT composite toughening agent, in which after the surface activation treatment is performed on AT, the active AT and the SEBS are mixed and added with a coupling agent to form a composite toughening agent with a core-shell structure.

The invention further aims to provide a high-performance PET/PA6 foam material aiming AT the defects of the prior art, and the SEBS/AT composite toughening agent is used to improve the crystallization rate of the material, reduce the warping property and enable the material to have better stability and consistency.

In order to solve the problems in the prior art, the invention provides an SEBS/AT composite toughening agent in a first aspect, wherein the SEBS/AT composite toughening agent has a core-shell structure formed by taking active AT as a core and SEBS as a shell, and the ratio of the particle size of the SEBS/AT composite toughening agent to the particle size of the active AT is 1000:3-1000: 11.

The particle size ratio in the scheme is a more preferable ratio range obtained by technicians on the basis of a large number of experiments, because in the preparation process of the SEBS/AT composite toughening agent, the active AT can be depolymerized to form a nano-rod body, the SEBS is coated on the surface of the nano-active AT to obtain the SEBS/AT composite toughening agent, the ratio range can stably control the particle size of the SEBS/AT composite toughening agent in the more preferable range, and if the ratio is more than 1000:11, the particle size of the toughening agent is possibly smaller, and the toughening effect on the composite material is not obvious; if the ratio is less than 1000:3, the grain size of the toughening agent is possibly too large, more toughening agents are required to be added to achieve the same toughening effect, the production cost is increased, and the rigidity of the material is reduced.

Furthermore, in the SEBS/AT composite toughening agent, the particle size of the active AT serving as a core structure is 90-110 nm.

Further, the SEBS/AT composite toughening agent is prepared from the following raw materials in parts by weight:

SEBS：50％-80％；

active AT: 19.7% -49.7%;

initiator: 0.01-0.05 per mill;

antioxidant: 0.2% -0.3%;

and uniformly mixing the raw materials, and extruding and granulating to obtain the SEBS/AT composite toughening agent.

In the scheme, the methoxy group of the silane coupling agent KH570 is coupled through condensation reaction of a chemical bond and hydroxyl on the surface of AT, under the action of an initiator DCP, a double bond of the silane coupling agent KH can form a free radical and SEBS for graft reaction, the SEBS is a nonpolar substance and preferentially gathers on the surface of AT which is strong in polarity and is combined with KH570 by the chemical bond, and finally, an AT with a tough surface layer and a rigid core and a core-shell structure toughening system with a silane coupling agent are formed.

Preferably, the SEBS/AT composite toughening agent comprises the following raw materials in a preferable ratio:

SEBS：65％-70％；

active AT: 29.7% -34.7%;

initiator: 0.01-0.03 per mill;

antioxidant: 0.2 to 0.3 percent.

Further, the initiator in the scheme is DCP; the antioxidant is B225.

In the scheme, the dosage of the initiator is within the dosage range obtained by technicians on the basis of a large number of experiments, when the dosage of the initiator exceeds 0.05 per mill, gel is easily generated in the reaction process, and the toughening efficiency of the composite toughening agent is influenced, and if the dosage of the initiator is less than 0.01 per mill, the grafting rate is influenced, so that the yield of the composite toughening agent with the core-shell structure is reduced, and the toughening effect is influenced.

The second aspect of the invention provides a preparation method of an SEBS/AT composite toughening agent, which comprises the following steps:

s1, preparing active AT;

s2, preparing the SEBS/AT composite toughening agent with the core-shell structure by taking the active AT as the core and the SEBS as the shell.

Further, in step S1, the active AT is obtained through a drying process, a depolymerization process, a mixing process of mixing with a coupling agent, a coupling reaction process, and a solvent removal process.

Further, the drying process is as follows: stirring AT AT 80-100 deg.C for 30-60min AT a first stirring speed;

the first stirring speed is 3000-.

Further, the particle diameter of AT AT the time of proceeding to step S1 is 2 to 8 μm, and the aspect ratio is 15 to 30.

The temperature and the first stirring speed in the drying process are more preferable parameters obtained by technicians on the basis of a great amount of experiments, and the AT can be dried in a shorter time by stirring AT 80-100 ℃ and AT a stirring speed of 3000-4000 rpm.

Furthermore, the drying process also comprises a depolymerization process of AT, and more than 90 percent of AT is depolymerized to form nanorods with the diameter of 90-110nm and the length-diameter ratio of more than 80 in the depolymerization process.

In the process, the nanorod obtained through depolymerization is used as the core of the SEBS/AT composite toughening agent, the particle size of the SEBS/AT composite toughening agent can be accurately controlled, and the phenomenon that the diameter of the SEBS/AT composite toughening agent is too large to cause an unobvious toughening effect or the addition amount of the toughening agent is increased when the same toughening effect is achieved due to too small diameter is avoided, so that the cost is increased.

Further, when the AT is dried to be in a fluffy state, the drying process is finished, and the mixing process is started.

In the scheme, the fluffy AT has lower density, can be more easily mixed with the coupling agent, and improves the mixing uniformity and the coupling reaction rate of the coupling agent and the AT.

Further, the mixing process is as follows: spraying the coupling agent solution into AT in a form of spray under stirring AT a second stirring speed;

the second stirring speed is 500-600 rpm.

The second stirring speed in the above scheme is a more preferable parameter obtained by a skilled person on the basis of a large number of experiments, and AT a stirring speed of 500-600rpm, the coupling agent can be fully mixed with the AT, and meanwhile, the coupling agent is prepared into a solution which is sprayed into the AT in a spraying manner to be fully mixed with the AT, and the atomized coupling agent solution has a smaller weight and can be uniformly attached to the AT, so that the mixing uniformity of the AT and the coupling agent is further improved.

Preferably, the coupling agent solution is sprayed into the AT in three portions.

Among the above-mentioned preferred scheme, because the coupling agent solution quality of atomizing is less, also can not be even under the stirring state with the AT intensive mixing of bottom, through in spraying the AT with the coupling agent solution in the stirring for three times, can make coupling agent and AT mixing uniformity fast more, improved mixing efficiency.

Further, the addition amount of the coupling agent solution is 6-8% of the AT mass.

Further, the coupling agent solution comprises:

a silane coupling agent;

ethanol;

acetic acid aqueous solution;

the volume ratio of the silane coupling agent to the ethanol is 1: 5-8;

the concentration of the acetic acid aqueous solution is 10 percent; the adding mass of the acetic acid water solution is 3-15% of the mass of the ethanol solution of the silane coupling agent.

Further, the silane coupling agent is KH 570.

In the scheme, the silane coupling agent can be dissolved in an aqueous solution of ethanol, and acetic acid is added to adjust the pH value of the system to be weakly acidic, so that the hydrolysis of the coupling agent is accelerated, and the coupling reaction speed of the coupling agent and the surface of the powder is improved; KH570 is selected because its molecular structure contains unsaturated double bonds, and can generate free radicals under the action of initiator to cross-link with the unsaturated bonds in SEBS.

Further, the coupling reaction process comprises the following steps: continuously stirring the mixture of AT and the coupling agent AT a third stirring speed for 10-30 min;

the third stirring speed was 1200-2200 rpm.

In the above reaction, the third stirring speed is a preferable stirring speed obtained by a skilled person based on a lot of experiments, the coupling reaction can be performed more rapidly at the above stirring speed, the conventional coupling reaction generally takes a long time, and the time of the coupling reaction is greatly shortened by controlling the stirring speed.

Further, the solvent removal process comprises the following steps: and drying the mixture subjected to the coupling reaction process AT 80-100 ℃ for 1-2h to obtain the active AT.

Further, in the step S2, the SEBS/AT composite toughening agent is prepared from the following raw materials:

SEBS：50％-80％；

active AT: 19.7% -49.7%;

initiator: 0.01-0.05 per mill;

antioxidant: 0.2% -0.3%;

and uniformly mixing the raw materials, and extruding and granulating to obtain the SEBS/AT composite toughening agent.

Further, the preparation process of the SEBS/AT composite toughening agent specifically comprises the following steps:

measuring all raw materials of the SEBS/AT composite toughening agent, uniformly mixing, and then putting the mixture into an extruder for extrusion and granulation to obtain the SEBS/AT composite toughening agent;

the temperature parameters of the extruder in the above process were as follows:

charging section	Mixing section	Metering section	Machine head
				100～120℃	160～180℃	180～190℃	160～170℃

The third aspect of the invention also provides a high-performance PET/PA6 foam material, which comprises the following raw materials in parts by weight:

PET：60％-70％；

PA6：20％-30％；

SEBS/AT composite toughening agent: 5% -8%;

SEBS-g-MA：1％-3％。

further, the raw materials are mixed and extruded to obtain a toughened PET/PA6 resin material, the toughened PET/PA6 resin material is foamed to obtain the high-performance PET/PA6 foamed material, and a foaming agent used in the foaming process is liquid CO₂And cyclopentane.

Furthermore, the high-performance PET/PA6 foaming material also comprises,

a volume aid: 0.5 to 1.5 percent.

Further, the compatibilizer is MDI.

In the scheme, the compatibilizer can perform chain extension reaction with PET and PA6 while improving the compatibility of the PET and PA6, so that the melt strength of the resin material is further improved.

Further, the specific process for preparing the toughened PET/PA6 resin material comprises the following steps:

after metering, all the raw materials are uniformly mixed and then sent into a double-screw extruder for extrusion and granulation, and the temperature of each temperature zone of the double-screw extruder is as follows:

further, the compatibilizer is fed into the extruder from three zones.

The beneficial effects of the above technical scheme are:

the composite toughening agent with the core-shell structure is prepared by compounding the SEBS and the active AT, so that the crystallization rate of the PET/PA6 foam material can be effectively improved, the warping property during molding is reduced, and the stability and consistency of the material are improved; drying AT AT a first stirring speed can realize full drying of AT in a short time, so that AT is dried to be fluffy and can be better and uniformly mixed with a coupling agent; the coupling agent is added into the AT in a spraying mode for three times AT a second stirring speed, so that the AT and the coupling agent are mixed more uniformly, the mixing time is shortened, and the mixing efficiency is improved; the third stirring speed can improve the speed of the coupling reaction between the AT and the coupling agent, and the preparation efficiency of the SEBS/AT composite toughening agent is improved; using a silane coupling agent KH570 as a coupling agent, wherein unsaturated double bonds on the KH570 can generate a crosslinking reaction with unsaturated bonds on SEBS (styrene-ethylene-butylene-styrene) forming a shell structure, so as to form the SEBS/AT composite toughening agent with a core-shell structure; in the process of preparing the SEBS/AT composite toughening agent, the dosage of the initiator is within the dosage range obtained by technicians on the basis of a large number of experiments, and when the dosage of the initiator is not within the range, the production efficiency and the toughening effect of the produced composite toughening agent are reduced.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention to the right. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a flow chart of preparation of active AT in the SEBS/AT composite toughening agent of the present invention.

FIG. 2 is a flow chart of the preparation of the high-performance PET/PA6 foam material of the present invention.

Detailed Description

To make the objects, technical solutions and advantages of the present invention clearer and more fully described below with reference to some examples, it will be understood by those skilled in the art that the following embodiments are only used for explaining the technical principles of the present invention and are not intended to limit the scope of the present invention. For example, although the present application describes the steps of the method of the invention in a particular order, these orders are not limiting, and one skilled in the art can perform the steps in a different order without departing from the underlying principles of the invention.

The invention discloses a preparation method of an SEBS/AT composite toughening agent, which comprises the following steps:

s1, preparing active AT;

s2, preparing the SEBS/AT composite toughening agent by taking the active AT prepared in the step S1 as a raw material.

The SEBS/AT composite toughening agent with the core-shell structure is formed by taking the active AT as the core and the SEBS as the shell, so that the crystallization rate of PET can be effectively improved, the stability and consistency of the PET/PA6 foam material are improved, and the warping property of the material is reduced.

Example one

As an embodiment of the present invention, this embodiment provides an SEBS/AT composite toughening agent, which comprises the following raw materials in parts by weight:

SEBS：50％；

active AT: 49.7 percent;

initiator: 0.01 per mill;

antioxidant: 0.3 percent;

the initiator is DCP, and the antioxidant is B225;

the ratio of the grain diameter of the prepared SEBS/AT composite toughening agent to the grain diameter of the active AT is 1000: 7.

Further, the diameter of the single active AT in the radial direction is about 110nm, and the diameter of the core formed by AT compounding is about 35 μm, so that the diameter of the prepared SEBS/AT composite toughening agent is 200 μm, namely, the active AT can be agglomerated due to the existence of huge surface energy in the process of forming the hard core, and the following examples are also not described again.

In the scheme, the methoxy group of the silane coupling agent KH570 is coupled through condensation reaction of a chemical bond and hydroxyl on the surface of AT, under the action of an initiator DCP, a double bond of the silane coupling agent KH can form a free radical and SEBS for graft reaction, the SEBS is a nonpolar substance and preferentially gathers on the surface of AT which is strong in polarity and is combined with KH570 by the chemical bond, and finally, an AT with a tough surface layer and a rigid core and a core-shell structure toughening system with a silane coupling agent are formed.

The preparation method of the SEBS/AT composite toughening agent comprises the following steps:

s1, preparing active AT;

s2, preparing the SEBS/AT composite toughening agent by taking the active AT prepared in the step S1 as a raw material;

in this embodiment, the AT is subjected to a drying process, a mixing process of mixing with a coupling agent, a coupling reaction process, and a solvent removal process to obtain active AT, and then the active AT is mixed with SEBS, an initiator is added, and extrusion granulation is performed by an extruder to obtain the SEBS/AT composite toughening agent.

Further, the amount of the coupling agent added is 6% by mass of AT.

Further, the steps for preparing active AT are as follows:

and (3) drying: AT is stirred AT a first stirring speed of 3000rpm in this example AT 100 ℃ for 60min until AT is dried to a fluffy state.

Drying AT the stirring speed of 3000rpm can be faster with the moisture in the AT deviate from, and the AT of drying to fluffy state can be better with coupling agent mix, has improved the mixed effect.

Mixing process: the coupling agent solution was sprayed in a spray form three times into AT for mixing while stirring AT a second stirring speed of 500 rpm.

Further, the drying process also comprises a depolymerization process of AT, wherein more than 90 percent of AT with the particle size of 2-8 μm and the length-diameter ratio of 15-30 is depolymerized to form nanorods with the diameter of 90-110nm and the length-diameter ratio of more than 80.

Further, in the above mixing process, the coupling agent solution includes,

a silane coupling agent;

ethanol;

acetic acid aqueous solution;

the volume ratio of the silane coupling agent to the ethanol is 1: 8;

the concentration of the acetic acid aqueous solution is 10 percent; the mass of the acetic acid aqueous solution added is 3% of that of the ethanol solution of the silane coupling agent.

The silane coupling agent can be dissolved in an aqueous solution of ethanol, and acetic acid is added to adjust the pH value of the system to be weakly acidic, so that the hydrolysis of the coupling agent is accelerated, and the coupling reaction speed of the coupling agent and the surface of the powder is improved.

The coupling agent is added into AT in a spraying mode for three times, the mixture is stirred AT the stirring speed of 500rpm, the coupling agent added into AT is mixed with AT while stirring, part of AT which is not sprayed to the coupling agent is turned up, and the coupling agent is sprayed again, so that the mixing uniformity is further improved, and the AT and the coupling agent are fully mixed by the scheme.

The coupling reaction process comprises the following steps: the mixture of AT and coupling agent was continuously stirred AT a third stirring speed of 1800rpm for 30 min.

And (3) solvent removal process: drying the mixture after the coupling reaction process is completed AT 100 ℃ for 2h until no ethanol smell can be generated in the mixture to obtain the active AT.

Furthermore, the coupling agent in the above scheme is a silane coupling agent KH570, and the reason why KH570 is used as the coupling agent is that the molecular structure of KH570 contains unsaturated double bonds, which can generate free radicals under the action of an initiator to perform a crosslinking reaction with unsaturated bonds in the toughening agent SEBS.

Further, in step S2, the raw materials are metered and mixed uniformly, and then added into a single-screw extruder for extrusion granulation, wherein the parameters of the extruder at temperature ranges are as follows:

charging section	Mixing section	Metering section	Machine head
				120℃	160℃	190℃	160℃

In the extrusion process, the methoxy group of the silane coupling agent KH570 is coupled through condensation reaction of a chemical bond and hydroxyl on the surface of AT, under the action of an initiator DCP, a free radical and SEBS can be formed on a double bond of the silane coupling agent KH, the double bond of the silane coupling agent KH can be grafted with the SEBS, the SEBS is a nonpolar substance and preferentially gathers on the surface of the AT with strong polarity, and finally, a core-shell structure toughening system with a tough SEBS surface layer, a rigid AT core and a silane coupling agent transition layer is formed.

Example two

As another embodiment of the present invention, this embodiment provides an SEBS/AT composite toughening agent, which comprises the following raw materials in parts by weight:

SEBS：80％；

active AT: 19.8 percent;

initiator: 0.05 per mill;

antioxidant: 0.2 percent;

the initiator is DCP, and the antioxidant is B225;

the ratio of the grain diameter of the prepared SEBS/AT composite toughening agent to the grain diameter of the active AT is 1000: 11.

Furthermore, the diameter of the active AT in the radial direction is 90nm, and the diameter of the prepared SEBS/AT composite toughening agent is 300 mu m.

The preparation method of the SEBS/AT composite toughening agent is the same as that of the first embodiment, except that in the embodiment, the addition amount of the coupling agent solution is 8% of the AT mass.

The procedure for the preparation of active AT is as follows:

and (3) drying: AT was stirred AT 80 ℃ for 60min AT a first stirring speed, which in this example was 4000rpm, until AT was dried to a fluffy state.

The drying is carried out AT the stirring speed of 2200rpm, so that the water in the AT can be removed more quickly, the AT dried to be in a fluffy state can be better mixed with the coupling agent, and the mixing effect is improved.

Mixing process: the coupling agent solution was sprayed in a spray form three times into AT for mixing while stirring AT a second stirring speed of 600 rpm.

Further, the drying process also comprises a depolymerization process of AT, wherein more than 90 percent of AT with the particle size of 2-8 μm and the length-diameter ratio of 15-30 is depolymerized to form nanorods with the diameter of 90-110nm and the length-diameter ratio of more than 80.

Further, in the above mixing process, the coupling agent solution includes,

a silane coupling agent;

ethanol;

acetic acid aqueous solution;

the volume ratio of the silane coupling agent to the ethanol is 1: 5;

the concentration of the acetic acid aqueous solution is 10 percent; the mass of the acetic acid aqueous solution added is 15% of the mass of the ethanol solution of the silane coupling agent.

The silane coupling agent can be dissolved in an aqueous solution of ethanol, and acetic acid is added to adjust the pH value of the system to be weakly acidic, so that the hydrolysis of the coupling agent is accelerated, and the coupling reaction speed of the coupling agent and the surface of the powder is improved.

The coupling agent is added into AT in a spraying mode for three times, the mixture is stirred AT the stirring speed of 600rpm, the coupling agent added into AT is mixed with AT while stirring, part of AT which is not sprayed to the coupling agent is turned up, and the coupling agent is sprayed again, so that the mixing uniformity is further improved, and the AT and the coupling agent are fully mixed by the scheme.

The coupling reaction process comprises the following steps: the mixture of AT and coupling agent was continuously stirred AT a third stirring speed of 2200rpm for 30 min.

And (3) solvent removal process: drying the mixture subjected to the coupling reaction process AT 80 deg.C for 1h until no ethanol smell can be generated in the mixture to obtain the active AT.

Furthermore, the coupling agent in the above scheme is a silane coupling agent KH570, and the reason why KH570 is used as the coupling agent is that the molecular structure of KH570 contains unsaturated double bonds, which can generate free radicals under the action of an initiator to perform a crosslinking reaction with unsaturated bonds in the toughening agent SEBS.

Further, the raw materials are metered and uniformly mixed and then added into a single-screw extruder for extrusion granulation, and the parameters of the temperature section of the extruder are as follows:

charging section	Mixing section	Metering section	Machine head
				120℃	160℃	190℃	160℃

In the extrusion process, the methoxy group of the silane coupling agent KH570 is coupled through condensation reaction of a chemical bond and hydroxyl on the surface of AT, under the action of an initiator DCP, a free radical and SEBS can be formed on a double bond of the silane coupling agent KH, the double bond of the silane coupling agent KH can be grafted with the SEBS, the SEBS is a nonpolar substance and preferentially gathers on the surface of the AT with strong polarity, and finally, a core-shell structure toughening system with a tough SEBS surface layer, a rigid AT core and a silane coupling agent transition layer is formed.

EXAMPLE III

As another embodiment of the present invention, this embodiment provides an SEBS/AT composite toughening agent, which comprises the following raw materials in parts by weight:

SEBS：65％；

active AT: 34.7 percent;

initiator: 0.03 per mill;

antioxidant: 0.3 percent;

the initiator is DCP, and the antioxidant is B225;

the ratio of the grain diameter of the prepared SEBS/AT composite toughening agent to the grain diameter of the active AT is 1000: 3.

Furthermore, the diameter of the active AT in the radial direction is 100nm, and the diameter of the prepared SEBS/AT composite toughening agent is 220 μm.

The preparation method of the SEBS/AT composite toughening agent is the same as that of the first embodiment, except that in the embodiment, the addition amount of the coupling agent solution is 7% of the AT mass.

The procedure for the preparation of active AT is as follows:

and (3) drying: AT was stirred AT 90 ℃ for 50min AT a first stirring speed, which in this example was 4000rpm, until AT was dried to a fluffy state.

The drying is carried out AT the stirring speed of 4000rpm, so that the water in the AT can be removed more quickly, the AT dried to be in a fluffy state can be better mixed with the coupling agent, and the mixing effect is improved.

Mixing process: the coupling agent solution was sprayed in a spray form three times to AT with stirring AT a second stirring speed of 550rpm for mixing.

Further, the drying process also comprises a depolymerization process of AT, wherein more than 90 percent of AT with the particle size of 2-8 μm and the length-diameter ratio of 15-30 is depolymerized to form nanorods with the diameter of 90-110nm and the length-diameter ratio of more than 80.

Further, in the above mixing process, the coupling agent solution includes,

a silane coupling agent;

ethanol;

acetic acid aqueous solution;

the volume ratio of the silane coupling agent to the ethanol is 1: 7;

the concentration of the acetic acid aqueous solution is 10 percent; the mass of the acetic acid aqueous solution added is 9% of the mass of the ethanol solution of the silane coupling agent.

The silane coupling agent can be dissolved in an aqueous solution of ethanol, and acetic acid is added to adjust the pH value of the system to be weakly acidic, so that the hydrolysis of the coupling agent is accelerated, and the coupling reaction speed of the coupling agent and the surface of the powder is improved.

The coupling agent is added into AT in a spraying mode for three times, the mixture is stirred AT the stirring speed of 550rpm, the coupling agent added into AT is mixed with AT while stirring, part of AT which is not sprayed to the coupling agent is turned up, and the coupling agent is sprayed again, so that the mixing uniformity is further improved, and the AT and the coupling agent are fully mixed by the scheme.

The coupling reaction process comprises the following steps: the mixture of AT and coupling agent was continuously stirred AT a third stirring speed of 2000rpm for 30 min.

And (3) solvent removal process: the mixture after completing the coupling reaction process was dried AT 95 ℃ for 1.5h until no ethanol smell appeared in the mixture to obtain the active AT.

Furthermore, the coupling agent in the above scheme is a silane coupling agent KH570, and the reason why KH570 is used as the coupling agent is that the molecular structure of KH570 contains unsaturated double bonds, which can generate free radicals under the action of an initiator to perform a crosslinking reaction with unsaturated bonds in the toughening agent SEBS.

Further, the raw materials are metered and uniformly mixed and then added into a single-screw extruder for extrusion granulation, and the parameters of the temperature section of the extruder are as follows:

charging section	Mixing section	Metering section	Machine head
				110℃	180℃	190℃	170℃

In the extrusion process, the methoxy group of the silane coupling agent KH570 is coupled through condensation reaction of a chemical bond and hydroxyl on the surface of AT, under the action of an initiator DCP, a free radical and SEBS can be formed on a double bond of the silane coupling agent KH, the double bond of the silane coupling agent KH can be grafted with the SEBS, the SEBS is a nonpolar substance and preferentially gathers on the surface of the AT with strong polarity, and finally, a core-shell structure toughening system with a tough SEBS surface layer, a rigid AT core and a silane coupling agent transition layer is formed.

Example four

As another embodiment of the present invention, this embodiment provides an SEBS/AT composite toughening agent, which has the same raw material ratio and preparation method as those of the first embodiment, except that the coupling agent solution is an acetic acid aqueous solution of a silane coupling agent.

In this example, the concentration of the acetic acid aqueous solution was 10%; the amount of silane coupling agent and aqueous acetic acid in the coupling agent solution was exactly the same as in example one.

On the other hand, the invention provides a high-performance PET/PA6 foam material, which uses the SEBS/AT composite toughening agent described in the above embodiment, and specifically comprises the following components:

EXAMPLE five

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which is prepared by using the SEBS/AT composite toughening agent described in the first embodiment as a raw material.

In this embodiment, the raw material ratio of the high-performance PET/PA6 foam material is as follows:

PET：60％；

PA6：30％；

SEBS/AT composite toughening agent: 8 percent;

SEBS-g-MA：1.5％；

a volume aid: 0.5 percent.

Further, the compatibilizer is MDI.

Further, the raw materials are mixed and extruded to obtain a toughened PET/PA6 resin material, and the toughened PET/PA6 resin material is foamed to obtain the high-performance PET/PA6 foamThe foaming agent used in the foaming process is liquid CO₂And cyclopentane.

In the scheme, the compatibilizer MDI can perform chain extension reaction with PET and PA6 while improving the compatibility of the PET and PA6, so that the melt strength of the resin material is further improved.

Further, the specific process for preparing the toughened PET/PA6 resin material comprises the following steps:

after metering, all the raw materials are uniformly mixed and then sent into a double-screw extruder for extrusion and granulation, and the temperature of each temperature zone of the double-screw extruder is as follows:

further, the compatibilizer is fed into the extruder from three zones.

EXAMPLE six

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which has the same preparation method as in the fifth embodiment, except that the SEBS/AT composite toughening agent described in the second embodiment is used as a raw material.

EXAMPLE seven

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which has the same preparation method as that of the fifth embodiment, except that the SEBS/AT composite toughening agent described in the third embodiment is used as a raw material.

Example eight

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which has the same preparation method as in the fifth embodiment, except that the SEBS/AT composite toughening agent described in the fourth embodiment is used as a raw material.

Example nine

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which has the same preparation method as the fifth embodiment, except that in this embodiment, the raw material ratio of the high performance PET/PA6 foam material is as follows:

PET：70％；

PA6：20.5％；

SEBS/AT composite toughening agent: 5 percent;

SEBS-g-MA：3％；

a volume aid: 1.5 percent.

Example ten

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which has the same preparation method as the fifth embodiment, except that in this embodiment, the raw material ratio of the high performance PET/PA6 foam material is as follows:

PET：69％；

PA6：20％；

SEBS/AT composite toughening agent: 8 percent;

SEBS-g-MA：2％；

a volume aid: 1 percent.

EXAMPLE eleven

As another embodiment of the present invention, this embodiment provides a high performance PET/PA6 foam material, which has the same preparation method as the fifth embodiment, except that in this embodiment, the raw material ratio of the high performance PET/PA6 foam material is as follows:

PET：60.5％；

PA6：30％；

SEBS/AT composite toughening agent: 8 percent;

SEBS-g-MA：1.5％。

comparative example 1

The comparative example provides a PET foam without the addition of PA6, toughening agent, and compatibilizer.

Comparative example No. two

The comparative example provides a PA6 foam without the addition of PET, toughening agent and compatibilizer.

Comparative example No. three

The comparative example provides a PET/PA6 foam, wherein the ratio of the mass components of PET and PA6 is 7: 3, no other auxiliary agent is added.

Comparative example No. four

The comparative example provides a PET/PA6 foam material, the preparation method is the same as the fourth example, and the raw material ratio is as follows:

PET：62％；

PA6：30％；

SEBS/AT composite toughening agent: 8 percent.

Comparative example five

The comparative example provides an SEBS/AT composite toughening agent, the preparation method is the same as the first example, and the difference is that the raw materials are in the following ratio:

SEBS：86％；

active AT: 13.7 percent;

initiator: 0.05 per mill;

antioxidant: 0.3 percent.

The prepared SEBS/AT composite toughening agent is prepared into the PET/PA6 foaming material by the same proportion and preparation method as the fifth embodiment.

Comparative example six

The comparative example provides an SEBS/AT composite toughening agent, the preparation method is the same as the first example, and the difference is that the raw materials are in the following ratio:

SEBS：44％；

active AT: 55.8 percent;

initiator: 0.05 per mill;

antioxidant: 0.2 percent.

The prepared SEBS/AT composite toughening agent is prepared into the PET/PA6 foaming material by the same proportion and preparation method as the fifth embodiment.

Experimental example 1

The purpose of this experimental example is to compare the toughening effect of the SEBS/AT composite toughening agent obtained by different preparation methods on the PET/PA6 foam material, and the comparison results are shown in the following table:

in the above results, the SEBS/AT composite toughening agent described in the fourth example is used to toughen the PET/PA6 foam material in the eighth example, and the SEBS/AT composite toughening agent described in the first example is used in the fifth exampleThe PET/PA6 foam material is toughened, and the comparison result shows that the PET/PA6 foam material prepared in the fifth example has the toughness tensile strength of 44MPa, the bending strength of 51MPa and the notch impact strength of 15.1KJ/m²While the PET/PA6 foam prepared in example eight had a tensile strength of 51MPa, a flexural strength of 62MPa, and a notched impact strength of 20.7KJ/m²The tensile strength, the bending strength and the notched impact strength of the PET/PA6 foam material prepared in the fifth embodiment are significantly higher than those of the PET/PA6 foam material prepared in the eighth embodiment, which shows that better toughening effect can be obtained by toughening the PET/PA6 foam material with the SEBS/AT composite toughening agent described in the first embodiment.

Secondly, as can be seen from the comparison results, the molding shrinkage of the PET/PA6 foam material prepared in example five is 1.51%, while the molding shrinkage of the PET/PA6 foam material prepared in example eight is 1.69%, which is significantly higher than that of example five, which illustrates that the warpage performance of the material can be significantly reduced while the PET/PA6 foam material is toughened by the SEBS/AT composite toughening agent described in example one. Can obtain better toughening effect

Experimental example two

The purpose of this experimental example was to test the mechanical properties of a PET/PA6 foam without toughening agent and a PET/PA6 foam with different toughening agents, the results of which are shown in the following table:

the test results were as follows:

from the above results, it can be seen that the notch impact strength and melt strength of the high-performance PET/PA6 foam materials prepared by using the SEBS/AT composite toughening agent in the fifth and tenth examples are significantly improved, and the molding shrinkage is significantly reduced, compared with the first, second, third and fourth comparative examples, which indicates that the high-performance PET/PA6 foam materials prepared by using the SEBS/AT composite toughening agent disclosed in the present application have better mechanical properties, higher stability, lower warpage and significant toughening effect.

Secondly, in comparative example four, the SEBS/AT composite toughening agent disclosed in the application is used for preparing the PET/PA6 foam material, while in comparative example three, the PET/PA6 foam material is prepared by only compounding the PET and the PA6, and the PET/PA6 foam material prepared in comparative example three has the notch impact strength of 8.7KJ/m²The melt strength is 2.56 mN; while the notched impact strength of the foamed material prepared in comparative example four was 12.7KJ/m²The melt strength is 12.5 mN; as can be seen from the comparison result of the third comparative example and the fourth comparative example, the SEBS/AT composite toughening agent has a remarkable toughening effect on the PET/PA6 foam material, and can remarkably improve the toughness of the material.

Meanwhile, from the comparison of the third comparative example and the fourth comparative example, the molding shrinkage of the PET/PA6 foam material prepared in the third comparative example is 2.23%; and the molding shrinkage of the foamed material prepared in comparative example four was 2.10%; the fourth comparative example shows that the shrinkage rate of the PET/PA6 foam material prepared by using the SEBS/AT composite toughening agent is low, so that the warpage of the material is low, and the dimensional stability and the morphology stability of the material are correspondingly improved by using a mold for molding.

Furthermore, as can be seen from the comparison of the data in the fifth embodiment and the tenth embodiment, the high-performance PET/PA6 foam material added with the compatibilizer in the fifth embodiment has improved properties, wherein the notch impact strength, melt strength and molding shrinkage are improved most obviously, which indicates that when MDI is used as the compatibilizer, the compatibility between PET and PA6 is improved significantly, and the uniformity of the system is improved; meanwhile, MDI can also carry out chain extension reaction with PET and PA6, so that the melt strength of the system is greatly improved, the crystallization rate of PET is further improved, and the molding shrinkage of the material is reduced.

The above embodiments are only preferred embodiments of the present invention, and not intended to limit the present invention in any way, and although the present invention has been disclosed by the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make various changes and modifications to the equivalent embodiments by using the technical contents disclosed above without departing from the technical scope of the present invention, and the embodiments in the above embodiments can be further combined or replaced, but any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention still fall within the technical scope of the present invention.