CN115536998A - Electromagnetic shielding heat conduction PBT/PET (polybutylene terephthalate/polyethylene terephthalate) based composite material and preparation method thereof - Google Patents
Electromagnetic shielding heat conduction PBT/PET (polybutylene terephthalate/polyethylene terephthalate) based composite material and preparation method thereof Download PDFInfo
- Publication number
- CN115536998A CN115536998A CN202211335682.2A CN202211335682A CN115536998A CN 115536998 A CN115536998 A CN 115536998A CN 202211335682 A CN202211335682 A CN 202211335682A CN 115536998 A CN115536998 A CN 115536998A
- Authority
- CN
- China
- Prior art keywords
- temperature
- zone
- pbt
- pet
- composite material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
- C08L67/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2296—Oxides; Hydroxides of metals of zinc
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/011—Nanostructured additives
Abstract
The invention discloses an electromagnetic shielding heat-conducting PBT/PET-based composite material and a preparation method thereof, wherein the electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials: PBT, PET, flake graphite, zinc oxide, barium ferrite, POE-g-GMA, gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, and beta- (4-hydroxyphenyl-3,5-di-tert-butyl) n-octadecyl propionate. The PBT/PET-based composite material has excellent electromagnetic shielding performance and heat conduction performance, and can be widely applied to the field of electronic components needing shielding and heat conduction functions.
Description
Technical Field
The invention belongs to the field of materials, and particularly relates to an electromagnetic shielding heat-conducting PBT/PET-based composite material and a preparation method thereof.
Background
Polybutylene terephthalate (PBT) and polyethylene terephthalate (PET) are two important thermoplastic engineering plastics, PBT has excellent mechanical strength, chemical corrosion resistance and thermal stability, and PET has the advantages of low cost, good rigidity and high thermal deformation temperature. The PBT/PET alloy can be prepared by melt blending of PBT and PET, combines the excellent performances of the PBT and the PET, and is widely applied to the fields of electronics and electrical appliance industry.
In recent years, with the development of the electronic and electrical industry, various devices provide high efficiency and convenience for production and life, and meanwhile, the problem of electromagnetic pollution is increasingly prominent. Electromagnetic interference can not only hinder the normal operation of equipment, cause information leakage, but also cause significant harm to human health. The electromagnetic shielding material realizes the shielding of electromagnetic waves through absorption or reflection loss, wherein materials mainly taking absorption loss are favored, and the materials convert the absorbed electromagnetic wave energy into joule heat energy, thereby effectively avoiding the problem of secondary pollution. Among electromagnetic shielding materials, conductive polymer composite materials have attracted much attention because of their advantages of light weight, corrosion resistance, easy processing, controllable performance, etc. Along with the update of electronic products, the power consumption of electronic and electrical equipment is continuously increased, the heat productivity of the equipment is rapidly increased, the temperature of the operating environment of the equipment is higher, and the adopted materials need to have excellent heat-conducting performance in order to ensure the normal operation of the equipment and maintain the service life of the equipment.
Currently, some studies on electromagnetic shielding PBT or PET are made in the prior art, such as: chinese patent CN 109135207A discloses a high-performance electromagnetic shielding PBT composite material and a preparation method thereof, wherein the composite material is prepared from the following components in parts by weight: 80 parts of PBT (polybutylene terephthalate) and 100 parts of PBT; the functionalized composite filler accounts for 10 parts and 20 parts; 0.1 part of antioxidant and 0.5 part of antioxidant; the functionalized composite filler is prepared by carrying out surface amino modification on fullerene and carrying out acidification treatment on PPTA fibers, and is of an interpenetrating network structure. Chinese patent CN 112940464A discloses a high-performance PBT/PET electromagnetic shielding composite material and a preparation method thereof. Push buttonThe paint comprises the following components in percentage by weight: 60 parts of polybutylene terephthalate, 20 parts of polyethylene terephthalate, 5 parts of compatilizer, 5 parts of carbon nano tube and 8 parts of Fe 3 O 4 5 parts of nano wires, 5 parts of stainless steel fibers, 0.6 part of surface treating agent and 0.5.0 part of antioxidant. Chinese patent CN 113621222A discloses a low-melting-point PBT electromagnetic shielding composite material and a preparation method thereof, wherein PBT base stock master batches, a graphene material and a dispersing agent are added into a high-speed stirrer to be stirred, then a compound compatilizer, an inorganic nano material, LCP fibers, flax fibers and carbon fibers are added to be continuously stirred, then the mixture is added into a double-screw extruder to be subjected to melt extrusion and granulation to obtain the modified PBT material. Chinese patent CN 111925630A discloses a high-strength electromagnetic shielding and heat conducting PBT/PET nano composite material and a preparation method thereof, wherein the nano composite material comprises the following components in parts by weight: 70 parts of polybutylene terephthalate, 20 parts of polyethylene terephthalate, 5 parts of toughening agent and Fe 3 O 4 5 parts of composite filler, 0.05 part of filler surface treating agent and 0.5.4 part of antioxidant. Chinese patent CN 103351584A discloses a heat-conducting PBT composite material with a shielding effect and a preparation method thereof, wherein the heat-conducting PBT composite material is prepared from the following raw materials in parts by weight: polybutylene terephthalate (PBT), aluminum powder, a toughening agent, a coupling agent, an antioxidant, a heat stabilizer and a lubricant. Chinese patent CN 107345051A discloses a heat-conducting PBT composite material with a shielding effect and a preparation method thereof. As can be seen from the above patents, in the prior art, the electromagnetic shielding function is mainly achieved by using carbon nano-filler such as graphene, or by using graphene Fe 3 O 4 The composite filler realizes electromagnetic shielding and heat conducting functions.
Disclosure of Invention
Based on the above, one of the purposes of the invention is to provide an electromagnetic shielding and heat conducting PBT/PET-based composite material, which has excellent electromagnetic shielding and heat conducting properties and can be widely applied to the field of electronic components requiring shielding and heat conducting functions.
The specific technical scheme for realizing the aim of the invention comprises the following steps:
the electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the barium ferrite is BaFe 12 O 19 Belongs to double complex dielectric materials; the POE-g-GMA is ethylene and octene copolymer grafted glycidyl methacrylate.
In some embodiments, the electromagnetic shielding and heat conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
in some embodiments, the electromagnetic shielding and heat conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
in some of these embodiments, the PBT has a number average relative molecular mass of from 25000 to 33000g/mol; the number-average relative molecular mass of the PET is 21000-29000 g/mol;
in some of these embodiments, the flake graphite has a particle size of 0.5 to 1 μm; the grain size of the zinc oxide is 25-35 nm.
In some of these examples, the POE-g-GMA has a glycidyl methacrylate grafting ratio of 1 to 1.4%.
In some embodiments, the barium ferrite is prepared by the following method:
(1) FeCl in molar ratio 3 ·6H 2 O：BaCl 2 ·2H 2 O = 11-11.6, weighing a certain amount of FeCl 3 ·6H 2 O and BaCl 2 ·2H 2 Adding O into deionized water for dissolving, and then transferring the mixed salt solution into a burette A for later use; in molar ratio of Na 2 CO 3 ：BaCl 2 ·2H 2 O =8 to 9, and Na 2 CO 3 : naOH = 4.5-5.5, respectively, and Na is calculated 2 CO 3 Adding NaOH and the mixed alkali solution into deionized water by weight parts for dissolving, and transferring the obtained mixed alkali solution into a burette B for later use;
(2) And under the condition of continuously and continuously stirring, simultaneously dripping the burette A and the burette B into a beaker, controlling the pH value of the solution in the beaker to be 8-8.5, standing for 8-12 h after titration, washing and drying by using ethanol and deionized water respectively after suction filtration, calcining for 4-6 h at 700-800 ℃, and grinding to obtain the barium ferrite.
The invention also aims to provide a preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material.
The specific technical scheme for realizing the aim of the invention comprises the following steps:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100-115 ℃ for 2-4 hours, cooling, and adding the cooled PBT, the PET, the POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 95-105 ℃, stirring for 0.5-1 h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.5-1 h, and cooling to room temperature;
(3) Adding the mixed material obtained in the step (1) into a parallel double-screw extruder through a feeder, adding the mixed material obtained in the step (2) into the parallel double-screw extruder (totally eight zones) (for example, a third zone) in the lateral direction (for example) for melt extrusion and granulation, wherein the process parameters comprise: the temperature of the first zone is 240-260 ℃, the temperature of the second zone is 245-265 ℃, the temperature of the third zone is 250-270 ℃, the temperature of the fourth zone is 255-275 ℃, the temperature of the fifth zone is 255-275 ℃, the temperature of the sixth zone is 255-275 ℃, the temperature of the seventh zone is 255-275 ℃, the temperature of the eighth zone is 250-270 ℃, the temperature of the die head is 250-270 ℃ and the rotating speed of the screw is 350-650 rpm.
In some embodiments, the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 105-110 ℃ for 2.5-3.5 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) n-octadecyl propionate into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 97-103 ℃, stirring for 0.6-0.9 h, adding the gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 0.6-0.9 h, and cooling to room temperature;
(3) Adding the mixed material obtained in the step (1) into a parallel double-screw extruder through a feeder, adding the mixed material obtained in the step (2) into the parallel double-screw extruder (totally eight zones) (for example, a third zone) in the lateral direction (for example) for melt extrusion and granulation, wherein the process parameters comprise: the temperature of the first zone is 245-255 ℃, the temperature of the second zone is 250-260 ℃, the temperature of the third zone is 255-265 ℃, the temperature of the fourth zone is 260-270 ℃, the temperature of the fifth zone is 260-270 ℃, the temperature of the sixth zone is 260-270 ℃, the temperature of the seventh zone is 260-270 ℃, the temperature of the eighth zone is 255-265 ℃, the temperature of the die head is 255-265 ℃ and the rotating speed of the screw is 400-600 rpm.
In some of these embodiments, the screw shape of the parallel twin screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D of the screw is 35-55; the screw is provided with more than 1 (including 1) meshing block area and more than 1 (including 1) reverse thread area.
In some of these embodiments, the ratio L/D of the length L of the screw to the diameter D is between 40 and 50; and 2 meshing block areas and 1 reverse thread area are arranged on the screw rod.
In some embodiments, in step (1) and/or step (2), the agitator is a high-speed agitator and the rotation speed is 500-1500 rpm.
The electromagnetic shielding heat-conducting PBT/PET-based composite material has the following functions of the raw materials:
the thermal conductivity of the PBT/PET-based composite material is improved by compounding the crystalline flake graphite and the zinc oxide, and a thermal conduction channel is constructed by utilizing the layered structure of the crystalline flake graphite to perform the intercalation or bridging action on the zinc oxide, so that the damage of the high filling amount of a single thermal conduction filler to the mechanical property of a thermal conduction material is reduced. The flake graphite is of a flake structure, and the flake graphite is independently used as a heat conducting filler, so that the flake graphite is difficult to contact with each other if layers of the flake graphite are not contacted with each other due to certain orientation of the flake graphite in contact; the zinc oxide is of a spherical structure, and when the zinc oxide is independently adopted as the heat-conducting filler, gaps are easily formed due to small contact surfaces among particles. The flake graphite and the zinc oxide are compounded to be used as the heat conducting filler, so that the flake graphite can form intercalation and bridging among zinc oxide particles, and the framework of a heat conducting channel is facilitated, and the heat conducting coefficient of the material is improved.
Barium ferrite (BaFe) 12 O 19 ) The material is a double-complex dielectric material, has higher natural resonance frequency, and the hexagonal sheet structure can realize good absorption of microwave band electromagnetic waves. The main wave absorption loss mechanism of barium ferrite is natural resonance loss, and under the condition of not adding external magnetic field, the changing magnetic field of incident electromagnetic wave can be matched with magnetocrystalline anisotropy field H of material A Interaction occurs and precession resonance is generated, but when the frequency f of the electromagnetic field and the eigenfrequency f of the crystal are changed by incident electromagnetic wave m Meanwhile, the ferrite crystal absorbs a great deal of energy of the electromagnetic wave, thereby achieving the effect of wave absorption.
POE-g-GMA is ethylene and octene copolymer grafted glycidyl methacrylate, and the grafting rate of the glycidyl methacrylate is 1-1.4%. The epoxy group of the POE-g-GMA can react with the terminal hydroxyl and the terminal carboxyl of PBT and PET, so that the compatibility and the interface adhesion of the POE-g-GMA and PBT and PET base material resin are improved, and the sensitivity of the polyester material to the notch strength is effectively improved.
Gamma- (2,3-epoxypropoxy) propyl trimethoxy silane is an epoxy functional silane. By coating gamma- (2,3-epoxy propoxy) propyl trimethoxy silane on the crystalline flake graphite, the zinc oxide and the barium ferrite, epoxy groups of the crystalline flake graphite, the zinc oxide and the barium ferrite can react with terminal hydroxyl and terminal carboxyl of PBT and PET, the dispersibility and compatibility of the crystalline flake graphite, the zinc oxide and the barium ferrite in PBT and PET base material resin are effectively improved, and thus the heat-conducting property and the electromagnetic shielding property of the PBT/PET-based composite material are improved.
The beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester is a phenol lipidated compound with excellent performance, and has the advantages of no smell, good compatibility with polymer resin, high extraction resistance, high oxygen resistance, difficult coloring, small volatility, no pollution, washing resistance and the like.
Compared with the prior art, the electromagnetic shielding heat conduction PBT/PET base composite material and the preparation method thereof provided by the invention have the following beneficial effects:
1. the invention improves the heat-conducting property of the PBT/PET-based composite material by compounding the flake graphite and the zinc oxide, improves the electromagnetic shielding property of the PBT/PET-based composite material by using the double-dielectric material barium ferrite, adopts POE-g-GMA to toughen the PBT/PET-based composite material, and improves the dispersity and compatibility of the flake graphite, the zinc oxide and the barium ferrite in PBT and PET base material resin by coating the flake graphite, the zinc oxide and the barium ferrite with gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, thereby improving the heat-conducting property and the electromagnetic shielding property of the PBT/PET-based composite material.
2. The preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material has the advantages of simple process, easiness in control and low requirement on equipment, all used equipment are general polymer processing equipment, the investment is low, and the industrial production is facilitated.
Drawings
FIG. 1 is a flow chart of a preparation process of the electromagnetic shielding heat-conducting PBT/PET-based composite material.
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
The reaction mechanism of the electromagnetic shielding heat-conducting PBT/PET-based composite material is as follows (see a preparation process flow chart in figure 1):
wherein R1 is POE-g-GMA or gamma- (2,3-epoxy propoxy) propyl trimethoxy silane coated crystalline flake graphite, zinc oxide and barium ferrite; r2 is PBT or PET.
Mechanism of reaction
According to the reaction formula, epoxy groups of POE-g-GMA and gamma- (2,3-epoxypropoxy) propyl trimethoxy silane coated crystalline flake graphite, zinc oxide and barium ferrite can react with terminal hydroxyl and terminal carboxyl of PBT and PET, so that the compatibility and interface cohesiveness of POE-g-GMA, PBT and PET base material resin are improved, the sensitivity of a polyester material to notch strength is effectively improved, and the dispersity and compatibility of crystalline flake graphite, zinc oxide and barium ferrite in PBT and PET base material resin are effectively improved, so that the heat conducting property and the electromagnetic shielding property of the PBT/PET base composite material are improved.
The raw materials used in the examples and comparative examples of the present invention were as follows:
PBT, with a number average molecular weight of 29000g/mol, was purchased from Catharan petrochemical Co., ltd, taiwan.
PET, number average molecular weight 25000g/mol, available from Huarun composites, inc., changzhou.
Flake graphite, particle size 0.8 μm, was purchased from Ningbo Haiyingding Industriage chemical Co.
Zinc oxide, particle size 30nm, was purchased from Xuancheng Crystal-Rui New Material Co.
FeCl 3 ·6H 2 O, available from Dou Ke Longman chemical plant.
BaCl 2 ·2H 2 O, available from Dou Ke Longman chemical industry reagent works.
Na 2 CO 3 From chemical reagents of the national drug group, ltd.
NaOH, available from the national pharmaceutical group Chemicals, inc.
Ethanol, available from national pharmaceutical group chemical agents, ltd.
Deionized water, purchased from national pharmaceutical group chemical agents, ltd.
POE-g-GMA, a glycidyl methacrylate graft of 1.2%, was purchased from Shenyang Ketong plastics Co., ltd.
Gamma- (2,3-epoxypropoxy) propyltrimethoxysilane, available from changda new materials science and technology ltd.
N-octadecyl beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionate, available from Hubei Xin run chemical Co., ltd.
The barium ferrite used in the following examples and comparative examples was prepared by a method comprising the steps of:
(1) FeCl in molar ratio 3 ·6H 2 O：BaCl 2 ·2H 2 O =11.3, 305.3g of FeCl was weighed out 3 ·6H 2 O and 24.4g of BaCl 2 ·2H 2 Adding O into 1000mL of deionized water for dissolving, and then transferring the mixed salt solution into a burette A for later use; in molar ratio of Na 2 CO 3 ：BaCl 2 ·2H 2 O =8.5, and Na 2 CO 3 : naOH =5, and 90.1g of Na was added to each of the solutions 2 CO 3 Adding 6.8g of NaOH into 500mL of deionized water for dissolving, and then transferring the obtained mixed alkali solution into a burette B for later use;
(2) And under the condition of continuously and continuously stirring, simultaneously dripping the burette A and the burette B into a beaker, controlling the pH value of the solution in the beaker to be 8.2, standing for 10 hours after titration, washing and drying by using ethanol and deionized water respectively after suction filtration, calcining for 5 hours at 750 ℃, and grinding to obtain the barium ferrite.
The present invention will be described in detail with reference to specific examples.
Embodiment 1 electromagnetic shielding heat-conducting PBT/PET-based composite material and preparation method thereof
The electromagnetic shielding heat conduction PBT/PET base composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 4 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 95 ℃, stirring for 1h, adding the gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 1h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 240 ℃, the temperature in the second zone was 245 ℃, the temperature in the third zone was 250 ℃, the temperature in the fourth zone was 255 ℃, the temperature in the fifth zone was 255 ℃, the temperature in the sixth zone was 255 ℃, the temperature in the seventh zone was 250 ℃, the temperature in the eighth zone was 250 ℃, and the screw speed was 350rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 35; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 500 revolutions per minute.
Embodiment 2 electromagnetic shielding heat conduction PBT/PET base composite material and preparation method thereof
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 115 ℃ for 2 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 105 ℃, stirring for 0.5h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.5h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (a third zone) for melt extrusion, and granulating, wherein the process parameters comprise: the temperature in the first zone was 260 deg.C, the temperature in the second zone was 265 deg.C, the temperature in the third zone was 270 deg.C, the temperature in the fourth zone was 275 deg.C, the temperature in the fifth zone was 275 deg.C, the temperature in the sixth zone was 275 deg.C, the temperature in the seventh zone was 275 deg.C, the temperature in the eighth zone was 270 deg.C, the temperature in the die head was 270 deg.C, and the screw speed was 650rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 55; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1500 rpm.
Embodiment 3 electromagnetic shielding heat conduction PBT/PET base composite material and preparation method thereof
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat conduction PBT/PET base composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 105 ℃ for 3.5 hours, cooling, and adding the cooled PBT, the PET, the POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 97 ℃, stirring for 0.9h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.9h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 245 ℃, the temperature in the second zone was 250 ℃, the temperature in the third zone was 255 ℃, the temperature in the fourth zone was 260 ℃, the temperature in the fifth zone was 260 ℃, the temperature in the sixth zone was 260 ℃, the temperature in the seventh zone was 260 ℃, the temperature in the eighth zone was 255 ℃, the temperature in the die head was 255 ℃ and the screw speed was 400rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 40; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 500 revolutions per minute.
Embodiment 4 electromagnetic shielding heat conduction PBT/PET base composite material and preparation method thereof
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (a third zone) for melt extrusion, and granulating, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Embodiment 5 electromagnetic shielding heat conduction PBT/PET base composite material and preparation method thereof
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 110 ℃ for 2.5 hours, cooling, and adding the cooled PBT, the PET, the POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 103 ℃, stirring for 0.6h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.6h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 255 ℃, the temperature in the second zone was 260 ℃, the temperature in the third zone was 265 ℃, the temperature in the fourth zone was 270 ℃, the temperature in the fifth zone was 270 ℃, the temperature in the sixth zone was 270 ℃, the temperature in the seventh zone was 270 ℃, the temperature in the eighth zone was 265 ℃, the temperature in the die head was 265 ℃ and the screw speed was 600rpm.
The shape of the screw of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D of the screw is 50; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1500 rpm.
Embodiment 6 electromagnetic shielding heat conduction PBT/PET base composite material and preparation method thereof
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, the PET, the POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) n-octadecyl propionate into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Embodiment 7 electromagnetic shielding heat conduction PBT/PET base composite material and preparation method thereof
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Comparative example 1
The electromagnetic shielding heat conduction PBT/PET base composite material of the comparative example is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Comparative example 2
The electromagnetic shielding heat conduction PBT/PET based composite material of the comparative example is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite and zinc oxide into a stirrer, heating to 100 ℃, stirring for 0.75h, adding gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Comparative example 3
The electromagnetic shielding heat conduction PBT/PET based composite material of the comparative example is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT and PET and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Comparative example 4
The electromagnetic shielding heat conduction PBT/PET based composite material of the comparative example is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat conduction PBT/PET base composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 1.5h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Comparative example 5
The electromagnetic shielding heat conduction PBT/PET base composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The screw shape of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
Comparative example 6
The electromagnetic shielding heat-conducting PBT/PET-based composite material is prepared from the following raw materials in parts by weight:
the preparation method of the electromagnetic shielding heat-conducting PBT/PET-based composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 100 ℃ for 3 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the zinc oxide and the barium ferrite into a stirrer, heating to 100 ℃, stirring for 0.75h, adding the gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 0.75h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder (totally eight zones) in the lateral direction (third zone) for melt extrusion and granulation, wherein the process parameters comprise: the temperature in the first zone was 250 ℃, the temperature in the second zone was 255 ℃, the temperature in the third zone was 260 ℃, the temperature in the fourth zone was 265 ℃, the temperature in the fifth zone was 265 ℃, the temperature in the sixth zone was 265 ℃, the temperature in the seventh zone was 265 ℃, the temperature in the eighth zone was 260 ℃, the temperature in the die head was 260 ℃ and the screw speed was 500rpm.
The shape of the screw of the parallel double-screw extruder is a single thread; the ratio L/D of the length L of the screw to the diameter D is 45; 2 meshing block areas and 1 reverse thread area are arranged on the screw rod; in the step (1) and the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 1000 revolutions per minute.
The following is a summary of the raw material compositions of examples 1-7 and comparative examples 1-6.
TABLE 1 summary of the raw material compositions of examples 1-7 and comparative examples 1-6
Examples 1 to 7 were prepared by adjusting the addition amounts of PBT, PET, flake graphite, zinc oxide, barium ferrite, POE-g-GMA, γ - (2,3-glycidoxy) propyltrimethoxysilane, and β - (4-hydroxyphenyl-3,5-di-tert-butyl) n-octadecyl propionate to prepare an electromagnetic shielding and heat conducting PBT/PET-based composite material, comparative example 1 was prepared by preparing an electromagnetic shielding and heat conducting PBT/PET-based composite material without adding flake graphite and zinc oxide, comparative example 2 was prepared by preparing an electromagnetic shielding and heat conducting PBT/PET-based composite material without adding barium ferrite, comparative example 3 was prepared by preparing a heat conducting and electromagnetic shielding PBT/PET-based composite material without adding POE-g-GMA, comparative example 4 was prepared by preparing an electromagnetic shielding and heat conducting PBT/PET-based composite material without adding γ - (2,3-glycidoxy) propyltrimethoxysilane, comparative example 5 was entirely flake graphite, and comparative example 6 was entirely zinc oxide.
The electromagnetic shielding and heat conducting PBT/PET base composite material prepared by the above examples and comparative examples is subjected to the following performance tests:
tensile strength: the tensile rate is 50mm/min according to the test of GB/T1040-2006 standard.
Notched impact strength: testing according to GB/T1843-2008 standard.
Electromagnetic shielding performance: cutting a sheet made of the electromagnetic shielding heat-conducting PBT/PET-based composite material into a sample with the size of 23 × 10 × 0.5mm, and testing the electromagnetic shielding performance of the material by using a vector network analyzer (model AGILENT N5244A PNA-X), wherein the testing method is a waveguide method, and the testing wave band is an X wave band of 8-12 GHz; the larger the test value, the better the electromagnetic shielding performance.
Heat conductivity: cutting a sheet made of the electromagnetic shielding heat-conducting PBT/PET-based composite material into a sample with the size of 20 x 0.5mm, and testing the heat-conducting performance of the material by using a heat conductivity tester (model NETZSCH LFA 457); the larger the test value, the better the heat conductivity.
The results of the performance tests are shown in table 2.
TABLE 2 Properties of electromagnetic shielding and thermal conductive PBT/PET based composites of examples 1-7 and comparative examples 1-6
As can be seen from table 2:
as the addition amount of PET increases, the tensile strength and notched impact strength of the PBT/PET-based composite material decrease. This is because PET is a polymer that is difficult to crystallize, and an increase in the content thereof gradually decreases the crystallization rate of the composite material, and the crystallinity after cooling also decreases, and thus the system tensile strength decreases. Meanwhile, the PET soft chain segment has shorter fatty chain and poorer flexibility than PBT chain segment, so the notch impact strength of the system is reduced.
With the reduction of the addition amount of barium ferrite, the maximum value of the electromagnetic shielding performance of the PBT/PET-based composite material is reduced. This is because barium ferrite (BaFe) 12 O 19 ) The material is a double-complex dielectric material, has higher natural resonance frequency, and the hexagonal sheet structure can realize good absorption of microwave band electromagnetic waves. The main wave absorption loss mechanism of barium ferrite is natural resonance loss, and under the condition of not adding external magnetic field, the changing magnetic field of incident electromagnetic wave can be matched with magnetocrystalline anisotropy field H of material A Interaction occurs and precession resonance is generated, but when the frequency f of the electromagnetic field and the eigenfrequency f of the crystal are changed by incident electromagnetic wave m Meanwhile, the ferrite crystal absorbs a great deal of energy of the electromagnetic wave, thereby achieving the effect of wave absorption.
With the reduction of the addition of the crystalline flake graphite and the zinc oxide, the heat-conducting property of the PBT/PET-based composite material is reduced. The thermal conductivity of the PBT/PET-based composite material is improved by compounding the flake graphite and the zinc oxide, and a thermal conduction channel is constructed by utilizing the intercalation or bridging effect of the flake graphite on the zinc oxide, so that the damage of the high filling amount of the single thermal conductive filler on the mechanical property of the thermal conductive material is reduced. The flake graphite is of a flake structure, and the flake graphite is independently used as a heat-conducting filler, and because the flake graphite has certain orientation in contact with each other, the flake graphite is not easy to contact with each other layer by layer; the zinc oxide is of a spherical structure, and when the zinc oxide is independently used as a heat-conducting filler, gaps are easily formed due to small contact surfaces among particles. The flake graphite and the zinc oxide are compounded to be used as the heat conducting filler, so that the flake graphite can form intercalation and bridging among zinc oxide particles, and the framework of a heat conducting channel is facilitated, and the heat conducting coefficient of the material is improved.
In conclusion, by adjusting the addition amounts of PBT, PET, crystalline flake graphite, zinc oxide, barium ferrite, POE-g-GMA, gamma- (2,3-epoxypropoxy) propyltrimethoxysilane and beta- (4-hydroxyphenyl-3,5-di-tert-butyl) n-octadecyl propionate, the electromagnetic shielding and heat conducting PBT/PET base composite material with excellent electromagnetic shielding performance, heat conducting performance and price advantage can be obtained under the synergistic cooperation of all the additives.
Compared with the embodiment 4, the comparative example 1 is the electromagnetic shielding heat conduction PBT/PET base composite material prepared without adding the crystalline flake graphite and the zinc oxide, and the crystalline flake graphite and the zinc oxide can form intercalation and bridging among zinc oxide particles by using the crystalline flake graphite as the heat conduction filler, so that the framework of a heat conduction channel is facilitated, the heat conduction coefficient of the material is improved, and the heat conduction performance of the comparative example 1 is inferior to that of the embodiment 4.
In comparison with example 4, comparative example 2 was a PBT/PET-based composite material having electromagnetic shielding and heat conducting properties prepared without adding barium ferrite due to barium ferrite (BaFe) 12 O 19 ) The material is a double-complex dielectric material, has higher natural resonance frequency, and the hexagonal sheet structure can realize good absorption of electromagnetic waves in a microwave band, so the maximum value of the electromagnetic shielding performance of the comparative example 2 is inferior to that of the example 4.
Compared with the embodiment 4, the comparative example 3 is that the electromagnetic shielding and heat conducting PBT/PET base composite material is prepared without adding POE-g-GMA, because POE-g-GMA is ethylene and octene copolymer grafted glycidyl methacrylate, the grafting rate of the glycidyl methacrylate is 1-1.4%. The epoxy group of the POE-g-GMA can react with the terminal hydroxyl and the terminal carboxyl of PBT and PET, so that the compatibility and the interface adhesion of the POE-g-GMA and PBT and PET base material resin are improved, and the sensitivity of the polyester material to the notch strength is effectively improved. Therefore, the notched impact strength of comparative example 3 is inferior to that of example 4.
Compared with example 4, comparative example 4 is the PBT/PET-based composite material with electromagnetic shielding and heat conduction prepared without adding gamma- (2,3-epoxy propoxy) propyl trimethoxy silane. Because gamma- (2,3-epoxy propoxy) propyl trimethoxy silane is epoxy functional group silane, the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane coats the crystalline flake graphite, the zinc oxide and the barium ferrite, and the epoxy group can react with the terminal hydroxyl and the terminal carboxyl of PBT and PET, the dispersibility and the compatibility of the crystalline flake graphite, the zinc oxide and the barium ferrite in PBT and PET base material resin are effectively improved, and the heat conducting property and the electromagnetic shielding property of the PBT/PET base composite material are improved. Therefore, comparative example 4 is inferior to example 4 in tensile strength, notched impact strength, maximum value of electromagnetic shielding property and heat conductive property.
Compared with example 4, comparative example 5 is that the heat conductive fillers are all flake graphite, and comparative example 6 is that the heat conductive fillers are all zinc oxide. Because the flake graphite is of a flake structure and the flake graphite is independently used as the heat conducting filler, the flake graphite has certain orientation in contact with each other, and if the flake graphite is not easy to contact with each other layer by layer; the zinc oxide is of a spherical structure, and when the zinc oxide is independently used as a heat-conducting filler, gaps are easily formed due to small contact surfaces among particles. The flake graphite and the zinc oxide are compounded to be used as the heat conducting filler, so that the flake graphite can form intercalation and bridging among zinc oxide particles, and the framework of a heat conducting channel is facilitated, and the heat conducting coefficient of the material is improved. Therefore, the thermal conductivity of comparative example 5 and comparative example 6 was inferior to that of example 4.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. The electromagnetic shielding heat-conducting PBT/PET-based composite material is characterized by being prepared from the following raw materials in parts by weight:
the barium ferrite is BaFe 12 O 19 Belongs to double complex dielectric materials; the POE-g-GMA is ethylene and octene copolymer grafted glycidyl methacrylate.
2. The electromagnetic shielding and heat conducting PBT/PET based composite material of claim 1 is characterized by being prepared from the following raw materials in parts by weight:
3. the electromagnetic shielding and heat conducting PBT/PET based composite material of claim 2 is characterized by being prepared from the following raw materials in parts by weight:
4. the electromagnetic shielding and heat conducting PBT/PET matrix composite material as claimed in claim 1, wherein the number-average relative molecular mass of the PBT is 25000-33000 g/mol; the number-average relative molecular mass of the PET is 21000-29000 g/mol.
5. The electromagnetic shielding and heat conducting PBT/PET matrix composite material of claim 1, wherein the crystalline flake graphite has a particle size of 0.5-1 μm; the particle size of the zinc oxide is 25-35 nm; the grafting rate of the POE-g-GMA glycidyl methacrylate is 1-1.4%.
6. The electromagnetic shielding and heat conducting PBT/PET matrix composite material as claimed in claim 1, wherein the preparation method of the barium ferrite is as follows:
(1) FeCl in molar ratio 3 ·6H 2 O：BaCl 2 ·2H 2 O = 11-11.6, weighing a certain amount of FeCl 3 ·6H 2 O and BaCl 2 ·2H 2 Adding O into deionized water for dissolving, and then transferring the mixed salt solution into a burette A for later use; in molar ratio of Na 2 CO 3 ：BaCl 2 ·2H 2 O =8 to 9, and Na 2 CO 3 : naOH = 4.5-5.5, respectively, and Na is calculated 2 CO 3 Adding NaOH and the mixed alkali solution into deionized water by weight parts for dissolving, and transferring the obtained mixed alkali solution into a burette B for later use;
(2) Under the condition of continuous and continuous stirring, the burette A and the burette B are simultaneously dripped into a beaker, the pH value of the solution in the beaker is controlled to be 8-8.5, the solution is kept stand for 8-12 h after titration, washed and dried by ethanol and deionized water respectively after suction filtration, calcined for 4-6 h at 700-800 ℃, and ground to obtain the barium ferrite.
7. A method for preparing the PBT/PET matrix composite material with electromagnetic shielding and heat conduction functions as claimed in any one of claims 1 to 6, characterized by comprising the following steps:
(1) Drying the PBT and the PET at the temperature of 100-115 ℃ for 2-4 hours, cooling, and adding the cooled PBT, the PET, the POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) propionic acid n-octadecyl ester into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 95-105 ℃, stirring for 0.5-1 h, adding the gamma- (2,3-epoxy propoxy) propyl trimethoxy silane, stirring for 0.5-1 h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder in the lateral direction, performing melt extrusion, and granulating, wherein the process parameters comprise: the temperature of the first zone is 240-260 ℃, the temperature of the second zone is 245-265 ℃, the temperature of the third zone is 250-270 ℃, the temperature of the fourth zone is 255-275 ℃, the temperature of the fifth zone is 255-275 ℃, the temperature of the sixth zone is 255-275 ℃, the temperature of the seventh zone is 255-275 ℃, the temperature of the eighth zone is 250-270 ℃, the temperature of the die head is 250-270 ℃ and the rotating speed of the screw is 350-650 rpm.
8. The preparation method of claim 7, wherein the preparation method of the electromagnetic shielding and heat conducting PBT/PET matrix composite material comprises the following steps:
(1) Drying the PBT and the PET at the temperature of 105-110 ℃ for 2.5-3.5 hours, cooling, and adding the cooled PBT, PET, POE-g-GMA and the beta- (4-hydroxyphenyl-3,5-di-tert-butyl) n-octadecyl propionate into a stirrer for mixing;
(2) Adding the crystalline flake graphite, the zinc oxide and the barium ferrite into a stirrer, heating to 97-103 ℃, stirring for 0.6-0.9 h, adding the gamma- (2,3-epoxypropoxy) propyl trimethoxy silane, stirring for 0.6-0.9 h, and cooling to room temperature;
(3) Adding the mixture mixed in the step (1) into a parallel double-screw extruder through a feeder, adding the mixture mixed in the step (2) into the parallel double-screw extruder in the lateral direction, performing melt extrusion, and granulating, wherein the process parameters comprise: the temperature of the first zone is 245-255 ℃, the temperature of the second zone is 250-260 ℃, the temperature of the third zone is 255-265 ℃, the temperature of the fourth zone is 260-270 ℃, the temperature of the fifth zone is 260-270 ℃, the temperature of the sixth zone is 260-270 ℃, the temperature of the seventh zone is 260-270 ℃, the temperature of the eighth zone is 255-265 ℃, the temperature of the die head is 255-265 ℃ and the rotating speed of the screw is 400-600 rpm.
9. The production method according to any one of claims 7 to 8, wherein the screw shape of the parallel twin-screw extruder is a single-screw thread; and/or the ratio L/D of the length L and the diameter D of the screw of the parallel double-screw extruder is 35-55; and/or more than 1 meshing block area and more than 1 reverse thread area are arranged on the screw of the parallel double-screw extruder; in the step (1) and/or the step (2), the stirrer is a high-speed stirrer, and the rotating speed is 500-1500 rpm.
10. The production method according to claim 9, wherein the parallel twin-screw extruder has a ratio L/D of a screw length L to a diameter D of 40 to 50; and/or the screw of the parallel double-screw extruder is provided with 2 meshing block areas and 1 reverse thread area.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211335682.2A CN115536998B (en) | 2022-10-28 | 2022-10-28 | Electromagnetic shielding heat conduction PBT/PET (polybutylene terephthalate/polyethylene terephthalate) based composite material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211335682.2A CN115536998B (en) | 2022-10-28 | 2022-10-28 | Electromagnetic shielding heat conduction PBT/PET (polybutylene terephthalate/polyethylene terephthalate) based composite material and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115536998A true CN115536998A (en) | 2022-12-30 |
| CN115536998B CN115536998B (en) | 2023-09-15 |
Family
ID=84717693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211335682.2A Active CN115536998B (en) | 2022-10-28 | 2022-10-28 | Electromagnetic shielding heat conduction PBT/PET (polybutylene terephthalate/polyethylene terephthalate) based composite material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115536998B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105273689A (en) * | 2014-07-18 | 2016-01-27 | 广东工业大学 | Novel multi-element structure composite conductive filling material |
| US20160152823A1 (en) * | 2013-07-01 | 2016-06-02 | Kaneka Corporation | High thermal conductivity thermoplastic resin composition with excellent injection moldability |
| CN111925630A (en) * | 2020-07-21 | 2020-11-13 | 浙江大学 | High-strength electromagnetic shielding and heat conducting PBT/PET nano composite material and preparation method thereof |
-
2022
- 2022-10-28 CN CN202211335682.2A patent/CN115536998B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160152823A1 (en) * | 2013-07-01 | 2016-06-02 | Kaneka Corporation | High thermal conductivity thermoplastic resin composition with excellent injection moldability |
| CN105273689A (en) * | 2014-07-18 | 2016-01-27 | 广东工业大学 | Novel multi-element structure composite conductive filling material |
| CN111925630A (en) * | 2020-07-21 | 2020-11-13 | 浙江大学 | High-strength electromagnetic shielding and heat conducting PBT/PET nano composite material and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| XING SUN: "Three-dimensional (3D) reduced graphene oxide (RGO)/zinc oxide (ZnO)/barium ferrite nanocomposites for electromagnetic absorption", 《 JOURNAL OF MATERIALS SCIENCE: MATERIALS IN ELECTRONICS》, vol. 28, no. 17, pages 12900 - 12908, XP036300823, DOI: 10.1007/s10854-017-7120-2 * |
| 王化宁: "棒状氧化锌/氧化石墨烯复合材料的制备及其吸附放射性铀性能研究", 《广东化工》, vol. 46, no. 8, pages 7 - 9 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115536998B (en) | 2023-09-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102719932B (en) | Preparation method of functional polyester fibers | |
| WO2017066937A1 (en) | Method for preparing graphene-polyester nanocomposite fiber | |
| CN100405886C (en) | Polyethylene composite film for shielding wideband electromagnetic wave and its preparing method | |
| CN105754278B (en) | A kind of nano inorganic mother particles of antibacterial plastics and preparation method thereof | |
| CN101469109A (en) | Polyester / metal fibre conductive, heat conducting and fast crystallization composite material and preparation thereof | |
| CN111925630B (en) | High-strength electromagnetic shielding and heat conducting PBT/PET nano composite material and preparation method thereof | |
| CN105002595A (en) | Polymer composite function fibers containing partial graphene, and preparation method thereof | |
| CN106936031A (en) | Electromagnetic shielding material, shielding shell for connector and cable | |
| CN105542447A (en) | Thermal conductive insulation plastic with low viscosity and high thermal conductivity and preparation method thereof | |
| CN114316577B (en) | Wave-absorbing polyamide composite material and preparation method thereof | |
| CN101205640A (en) | Method for producing skin-core structural micro-wave screening functional fibre by melt direct spinning | |
| CN109722022B (en) | Extrusion and blow molding grade glass fiber reinforced nylon material and preparation method thereof | |
| CN105385070A (en) | Wire and cable sheath processing technology based on nano calcium carbonate | |
| CN114907696A (en) | High CTI polyphenylene sulfide composite material and preparation method thereof | |
| CN115536998B (en) | Electromagnetic shielding heat conduction PBT/PET (polybutylene terephthalate/polyethylene terephthalate) based composite material and preparation method thereof | |
| JP2004143270A (en) | Liquid-crystal polyester resin composition | |
| CN102382468B (en) | Carbon nano tube reinforced polyphenylene sulfide material and preparation method thereof | |
| CN112663167A (en) | Flame-retardant polyester fiber and preparation method thereof | |
| CN115558285B (en) | Polyamide composite material and preparation method thereof | |
| CN104725812A (en) | Filling-reinforced PC/PET alloy and preparation method thereof | |
| CN103589144A (en) | Lightproof infrared-ray transmitting nylon PA12 material for automobile connectors | |
| CN104974423A (en) | Diatomite/polypropylene composite material and preparation method thereof | |
| CN105199564A (en) | Thermoset electromagnetic shielding powder coating | |
| CN104419179A (en) | Inorganic particle enhanced PC (polycarbonate) composite material and preparation method thereof | |
| CN107603137A (en) | A kind of semiconductive Polyether-ether-ketocable cable material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |