CN114836017A

CN114836017A - PBT-PC composite material and preparation method and application thereof

Info

Publication number: CN114836017A
Application number: CN202210423695.9A
Authority: CN
Inventors: 刘春艳; 王慧珊
Original assignee: Shanghai Zhonglei New Material Science Co ltd
Current assignee: Shanghai Zhonglei New Material Science Co ltd
Priority date: 2022-04-21
Filing date: 2022-04-21
Publication date: 2022-08-02

Abstract

The invention provides a PBT-PC composite material, a preparation method and an application thereof, wherein the PBT-PC composite material comprises the following components in parts by weight: 20-60 parts of PBT-graphene oxide composite material, 5-40 parts of PC resin, 5-20 parts of flame retardant and 5-40 parts of glass fiber; the PBT-graphene oxide composite material comprises the following components in parts by weight: 80-100 parts of PBT resin and 0.2-5 parts of graphene oxide. By compounding the PBT-graphene oxide composite material with specific components, the PC resin, the flame retardant and the glass fiber, the overall comprehensive performance of the composite material is greatly improved, the problems of warping and the like caused by nonuniform heated PBT are fundamentally solved, and the provided PBT-PC composite material has excellent crystallization performance, heat resistance, impact toughness, dimensional stability and flame retardance and can fully meet the performance requirements of peripheral parts of electrical equipment and engines on the material.

Description

PBT-PC composite material and preparation method and application thereof

Technical Field

The invention belongs to the technical field of polymer materials, and particularly relates to a PBT-PC composite material and a preparation method and application thereof.

Background

Polybutylene terephthalate (PBT) prepared from phthalic acid andthe 1, 4-butanediol is obtained by polycondensation, is a semi-crystalline engineering plastic with a relatively high crystallization rate, contains a benzene ring rigid chain in a molecular structure, endows the semi-crystalline engineering plastic with good solvent resistance, weather resistance and the like, and has good melt fluidity, good heat resistance, self lubrication, low water absorption and the like due to 4 methylene structures. However, the glass transition temperature T of PBT _g Low, only about 45 ℃, large molding shrinkage of the product, about 1.7-2.3 percent, strong notch sensitivity and poor impact toughness. Meanwhile, the problems of uneven size, warpage and the like occur due to uneven temperature and different oriented and crystallized directions in the crystallization process. Therefore, the modification of PBT material to improve its impact toughness and dimensional stability is an important research direction for its wide application in electronic and electric appliances, automobile engine periphery and precision products.

Polycarbonate (PC) has a combination of toughness, excellent creep resistance, heat resistance, and good dielectric properties, is one of five general-purpose engineering plastics, and is widely used in the fields of automobiles, electronics, machinery, and the like. The PC is added into the PBT matrix to prepare the polymer alloy material, so that the mechanical property, especially the impact toughness, of the material can be effectively improved, and the polymer alloy material is an effective means for modifying the PBT; but the PC and the PBT material are easy to generate ester exchange reaction, thereby influencing the crystallization property of the PBT material and reducing the heat resistance.

At present, the main method for improving the specific alloy material is to inhibit the ester exchange reaction of PC and PBT and control the addition amount of PC. For example, CN108342056A discloses a PC/PBT alloy and its products, the PC/PBT alloy includes the following components: 20-35 parts of PC resin, 5-80 parts of PBT resin and 0.1-2 parts of ester exchange inhibitor; the ester exchange inhibitor is prepared by compounding two or more of sodium dihydrogen phosphate, triphenyl phosphite, tetraethoxysilane, sodium dihydrogen phosphate, diethyl sulfate and diisooctyl phosphate. The alloy can slow down the ester exchange reaction in the processing process by adding the ester exchange inhibitor; but the crystallinity of the material is still low, so that the alloy product has serious warpage and poor dimensional stability. CN111286163A discloses a reinforced flame-retardant low-warpage PBT alloy material, which comprises: 35-50 parts of polybutylene terephthalate, 5-15 parts of polycarbonate, 15-30 parts of glass fiber and 5-15 parts of inorganic filler; 5-20 parts of compound flame retardant, 5-10 parts of toughening agent, 0.2-0.4 part of compound antioxidant, 0.1-0.3 part of lubricant, 0.1-0.3 part of ester exchange inhibitor and 0.1-0.3 part of anti-dripping agent. The amorphous polymer PC is introduced into the alloy material to reduce the crystallinity of the system, but the notch impact property of the material is lower, and the problem of heat resistance is not effectively solved, so that the application of the amorphous polymer PC to heat-resistant components such as the periphery of an engine is influenced.

In addition, the PBT-PC alloy is usually used for electronic equipment and automobile engine periphery, and is required to have good heat resistance and flame retardant property, and the common bromine and antimony compound is compounded to realize synergistic flame retardant, namely a bromine flame retardant and antimony white (Sb) ₂ O ₃ ) The flame retardant is compounded, has large addition amount, releases toxic gas during combustion, has hidden danger of environmental protection, and has great damage to human bodies. The conventional inorganic phosphorus-containing flame retardant is easy to generate micromolecule migration, so that the flame retardant performance is reduced, and the use requirement cannot be met.

Therefore, the development of a PBT-PC alloy material with good dimensional stability, heat resistance, toughness and flame retardance is a problem to be solved in the field.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a PBT-PC composite material and a preparation method and application thereof.

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

in a first aspect, the invention provides a PBT-PC composite material, which comprises the following components in parts by weight:

the PBT-graphene oxide composite material comprises the following components in parts by weight: 80-100 parts of PBT resin and 0.2-5 parts of graphene oxide.

In the PBT-PC composite material provided by the invention, the PBT resin and the graphene oxide form the composite material, the oxygen-containing functional group of the graphene oxide and the PBT resin are firstly reacted and compounded to construct heterogeneous nucleation points, and meanwhile, the graphene oxide is partially reduced in the compounding process to form an electric and heat conducting network, so that the phonon conduction rate is enhanced, the heat conductivity of the material is improved, the temperature conduction rate of the whole material is accelerated, uniform crystallization is promoted, and the conditions of warping and the like caused by nonuniform heating of the PBT are improved. The PBT-graphene oxide composite material and the PC resin are compounded and toughened, part of PBT ester exchange reaction groups react with graphene oxide, active sites are few, and ester exchange reaction with the PC resin is greatly reduced, so that the respective characteristics of the material are kept to a great extent, and the compatibility of two phases can be effectively improved by a small amount of residual reaction groups. Meanwhile, the introduction of the glass fiber realizes the enhancement of the composite material, and has the function of heterogeneous nucleation, thereby further improving the crystallization rate and the crystallinity; the flame retardant is coated by the graphene sheet layer again in the composite material system, meanwhile, the molecular gap is reduced due to the enhancement of the compatibility of two phases, the multi-layer constraint effectively prevents the migration of the flame retardant, and the effectiveness of the flame retardant is maintained. Therefore, the PBT-PC composite material greatly improves the integral crystallinity, heat resistance, impact toughness, dimensional stability and flame retardance of the material by compounding the specific PBT-graphene oxide composite material, the PC resin, the flame retardant and the glass fiber.

In the present invention, the PBT-graphene oxide composite material is 20-60 parts by weight, for example, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts, 38 parts, 40 parts, 42 parts, 45 parts, 48 parts, 50 parts, 52 parts, 55 parts or 58 parts by weight, and specific values therebetween are not limited to space and for the sake of brevity, and the present invention does not exhaustive list the specific values included in the range, preferably 30-50 parts by weight.

The PC resin is present in 5-40 parts by weight, for example, 6, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35 or 38 parts by weight, and specific values therebetween, which are not intended to be limiting in terms of space and simplicity, and are not exhaustive, and preferably 10-30 parts.

The flame retardant is present in an amount of 5 to 20 parts by weight, for example 6, 8, 10, 11, 13, 15, 17 or 19 parts by weight, and the ranges between these values are not exhaustive, and for reasons of brevity and clarity, the invention is not intended to be limited to the ranges specifically included, preferably 5 to 15 parts.

The glass fiber is 5-40 parts by weight, for example, 6 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts or 38 parts by weight, and specific values therebetween are not exhaustive for the sake of brevity and clarity.

In the PBT-graphene oxide composite material, the PBT resin is 80-100 parts, for example, 81 parts, 83 parts, 85 parts, 87 parts, 89 parts, 90 parts, 91 parts, 93 parts, 95 parts, 97 parts or 99 parts, and the specific values therebetween are limited by space and for the sake of brevity, and the specific values included in the range are not exhaustive.

The graphene oxide is 0.2 to 5 parts, for example, 0.3 part, 0.5 part, 0.8 part, 1 part, 1.5 part, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific values therebetween are not exhaustive, and for brevity, the invention does not include the specific values included in the range, preferably 0.5 to 5 parts.

Preferably, the mass percentage of the graphene oxide in the PBT-graphene oxide composite material is 0.5-5 parts and is less than or equal to 6%, for example, 0.1%, 0.2%, 0.5%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, and more preferably less than or equal to 2%; if the amount of the graphene oxide is too much, the dispersion difficulty of the graphene oxide is high, and the graphene oxide is agglomerated in a PBT resin matrix and a PBT-PC composite material, so that the performance of the PBT-PC composite material is influenced.

Preferably, the PBT resin has an intrinsic viscosity of 0.5-2.5dL/g, such as 0.8dL/g, 1dL/g, 1.2dL/g, 1.5dL/g, 1.8dL/g, 2dL/g, 2.2dL/g, or 2.4dL/g, and specific values therebetween, not to be limited by space and for the sake of brevity, the invention is not exhaustive of the specific values included in the ranges.

Preferably, the graphene oxide contains an oxygen-containing functional group including any one of a hydroxyl group, a carboxyl group, a carbonyl group, or an epoxy group, or a combination of at least two thereof.

Preferably, the graphene oxide is a thin layer graphene oxide, and the number of layers is 1 to 5, and may be, for example, 1 layer, 2 layers, 3 layers, 4 layers, or 5 layers.

Preferably, the graphene oxide has a size (sheet diameter ) in the order of micrometers, and is commercially available.

Preferably, the graphene oxide has a sheet diameter of 10-200 μm, for example, 20 μm, 50 μm, 80 μm, 100 μm, 110 μm, 130 μm, 150 μm, 170 μm or 190 μm, and specific values therebetween are not exhaustive, and for brevity and clarity, the invention is not limited to the specific values included in the range.

Preferably, the PBT-graphene oxide composite further includes 0.01-5 parts by weight of a coupling agent, for example, the coupling agent may be 0.05 part, 0.1 part, 0.2 part, 0.4 part, 0.5 part, 0.7 part, 0.9 part, 1 part, 1.5 part, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific point values therebetween are limited to space and for simplicity, and the invention does not exhaust the specific point values included in the range, and further preferably 0.1-1 part.

Preferably, the coupling agent comprises a silane coupling agent.

Preferably, the silane coupling agent includes any one of an amino-containing silane coupling agent, an alkenyl-containing silane coupling agent, or an epoxy-containing silane coupling agent, or a combination of at least two thereof.

Preferably, the silane coupling agent includes any one or a combination of at least two of gamma-aminopropyltriethoxysilane (KH550), gamma-glycidoxypropyltrimethoxysilane (KH560), gamma-methacryloxypropyltrimethoxysilane (KH570), N- (beta-aminoethyl) -gamma-aminopropyltrimethoxysilane (KH792), gamma-glycidoxypropyltriethoxysilane, N-aminoethyl-gamma-aminopropyltriethoxysilane, gamma-aminopropylmethyldiethoxysilane, N- (beta-aminoethyl) -gamma-aminopropyltriethoxysilane, or anilinomethyltrimethoxysilane.

Preferably, the PBT-graphene oxide composite further includes 0.01-0.5 parts by weight of an antioxidant, for example, the antioxidant may be 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts or 0.45 parts, and specific points therebetween are limited by space and for brevity, and the invention is not exhaustive list of the specific points included in the range.

Preferably, the PBT-graphene oxide composite material comprises, in parts by weight: 80-100 parts of PBT resin, 0.5-5 parts of graphene oxide, 0.01-5 parts of silane coupling agent and 0.01-0.5 part of antioxidant.

Preferably, the PBT-graphene oxide composite is prepared by a method comprising: and mixing PBT resin with graphene oxide, reacting and extruding to obtain the PBT-graphene oxide composite material.

Preferably, the reaction temperature is 210-.

Preferably, the reaction is carried out in a screw extruder.

Preferably, the screw speed of the screw extruder is 350-750rpm, for example, 400rpm, 450rpm, 500rpm, 550rpm, 600rpm, 650rpm or 700rpm, and specific values therebetween, for reasons of brevity and clarity, are not exhaustive and are not included in the scope of the invention.

Preferably, the mixing is performed in a blender mixer, which is intended to maintain homogeneity from the initial mixing of the materials.

Preferably, the mixing speed is 500-900rpm, such as 550rpm, 600rpm, 650rpm, 700rpm, 750rpm, 800rpm or 850rpm, and the specific values therebetween are limited for the sake of brevity and brevity, and the invention is not intended to be exhaustive of the specific values included in the ranges.

Preferably, the mixing time is 3-15min, for example 4min, 5min, 6min, 8min, 10min, 12min or 14min, and the specific values therebetween are limited for space and simplicity, and the invention is not intended to be exhaustive.

Preferably, the mixed material further comprises a coupling agent and/or an antioxidant.

Preferably, the PBT resin is pre-baked at 100-120 ℃ before mixing.

Preferably, the extrusion is followed by cooling, drying and pelletizing steps.

In the invention, the PBT-graphene oxide composite material is obtained by melt co-extrusion and reaction of PBT resin and Graphene Oxide (GO); the surface of GO contains a large number of oxygen-containing functional groups, such as hydroxyl (-OH), carbonyl (C (-O), carboxyl (-COOH) or epoxy (C-O-C), and the like, which are adsorbed with polar groups of a PBT resin molecular chain to form a 'physical cross-linking point', which becomes a heterogeneous nucleation point of PBT, promotes crystallization, and can simultaneously perform esterification reaction with ester groups on the PBT structure, thereby effectively enhancing the substrate binding property; the PBT-graphene oxide composite material is used as master batches to be melted and blended with a PC resin and other base materials again, so that the dispersity of GO can be further improved through shearing, the PBT resin is uniformly crystallized for the second time, meanwhile, the GO is partially reduced in the heating melting processing process, an excellent heat conduction network is formed due to the large specific surface area of the GO, the in-plane temperature of the material is uniform, and the warping problem caused by the nonuniform temperature of the PBT is substantially improved. In addition, during the compounding process of the PBT resin and the GO, the GO can be reduced to a certain degree, so that the overall physical properties of the material, such as the thermal conductivity, the dielectric property and the like, are further improved.

Further, the PBT-graphene oxide composite material is compounded with PC resin, and the PC resin effectively toughens the PBT; due to the addition of GO in the PBT-graphene oxide composite material, a large number of oxygen-containing functional groups on the surface of the composite material are firstly adsorbed and reacted with PBT, and the filler and the matrix have thermodynamic compatibility and can consume a large number of ester groups on the main chain of the PBT; ester groups on the PBT structure are consumed, so that the ester exchange reaction between PBT and PC in the PBT-PC composite material is avoided, the crystallization of PBT is effectively maintained, the PBT-PC composite material has good oil resistance and chemical resistance, and simultaneously good thermal property and dimensional stability are maintained, the Vicat softening temperature is higher than 130 ℃, and can reach 187 ℃ at most, so that the PBT-PC composite material is completely suitable for related parts around electrical equipment and engines.

Preferably, the PC resin comprises bisphenol a polycarbonate.

Preferably, the PC resin has a melt index of 5-40g/10min, such as 8g/10min, 10g/10min, 15g/10min, 20g/10min, 25g/10min, 30g/10min, 35g/10min or 38g/10min at 300 ℃ and 1.2kg, and specific values therebetween, which are not intended to be exhaustive for the purpose of disclosure and brevity.

Preferably, the mass ratio of the PC resin to the PBT-graphene oxide composite material is 1 (1.5-2.5), and may be, for example, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.1, 1:2.2, 1:2.3, or 1: 2.4.

Preferably, the flame retardant comprises a phosphorus-based flame retardant.

Preferably, the phosphorus-based flame retardant comprises any one or a combination of at least two of resorcinol bis (phenyl phosphate) (RDP), bisphenol a bis (diphenyl phosphate) (BDP), tris (2, 2-dibromomethyl-3-bromopropyl phosphonate), ammonium polyphosphate (APP), aluminum phosphinate (AHP), pentaerythritol phosphate (PEPA, 1-oxo-4-hydroxymethyl-1-phospha-2, 6, 7-trioxabicyclo [2,2,2] octane), triphenyl phosphate, tricresyl phosphate, tris (2, 6-dimethylphenyl) phosphine, brominated aromatic phosphate, red phosphorus or a phosphorus nitrogen built flame retardant, and further preferably triphenyl phosphate.

Preferably, the phosphorus-containing flame retardant comprises a phosphorus-containing polymer flame retardant, and the molecular weight of the phosphorus-containing polymer flame retardant is more than or equal to 20000.

Preferably, the phosphorus-nitrogen compounded flame retardant comprises a phosphorus-nitrogen intumescent flame retardant.

Preferably, the flame retardant further comprises an inorganic filler flame retardant.

Preferably, the inorganic filler flame retardant comprises any one or a combination of at least two of talc, calcium carbonate, mica, silica lime, glass beads, montmorillonite, kaolin, aluminum hydroxide or magnesium hydroxide, and further preferably talc.

Preferably, the flame retardant comprises a combination of a phosphorus flame retardant and an inorganic filler flame retardant, namely a phosphorus-inorganic compound flame retardant.

The mass ratio of the phosphorus-based flame retardant to the inorganic filler flame retardant is preferably (1 to 10):1, and may be, for example, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, or 9.5: 1.

As a preferable technical scheme of the invention, the flame retardant comprises a combination of a phosphorus flame retardant and an inorganic filler flame retardant (phosphorus-inorganic compound flame retardant), which is compounded with glass fiber, PC resin and a PBT-graphene oxide composite material, the inorganic filler flame retardant, the glass fiber and the graphene oxide have heterogeneous nucleation effect on the PBT resin, so that the crystallization rate of the material is greatly improved, meanwhile, the graphene oxide has a larger specific surface area, a good lamellar heat conduction network is constructed with physical adsorption and esterification reaction of the PBT resin, secondary constraint on the flame retardant is also formed, so that the problem of flame retardant precipitation is solved, meanwhile, the graphene oxide is subjected to graphitization reaction in the combustion process, the inorganic flame retardant promotes condensed phase flame retardance in the combustion process, a compact carbon layer is formed together, so that the flame retardance of the PBT-PC composite material is remarkably improved, can reach the flame retardant grade of 0.8mm V-0.

Preferably, the glass fibers comprise any one of or a combination of at least two of glass roving, chopped fibrils, continuous long fibers, alkali-free glass fibers or flat glass fibers.

Preferably, the PBT-PC composite material contains 5-40 parts of glass fiber, and the glass fiber is compounded with other components, so that the PBT-PC composite material has a reinforcing effect, has a heterogeneous nucleation effect on PBT resin, and is beneficial to improving the crystallization rate of the composite material.

The mass percentage of the glass fiber in the PBT-PC composite material is 5-40%, for example, 6%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35% or 38%, and the specific values therebetween, which are limited by space and for brevity, the invention is not exhaustive list of the specific values included in the range, preferably 20-30%.

Preferably, the PBT-PC composite further includes 0.01-0.5 parts by weight of a transesterification inhibitor, for example, the transesterification inhibitor may be 0.03 parts, 0.05 parts, 0.08 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts or 0.45 parts, and specific points therebetween are not exhaustive, and for brevity, the invention is not exhaustive list of the specific points included in the range.

Preferably, the transesterification inhibitor is a phosphorus-containing compound.

Preferably, the transesterification inhibitor comprises any one of sodium dihydrogen phosphate, ammonium hypophosphite, sodium acid pyrophosphate, ammonium phosphite, triphenyl phosphite or triphenyl phosphate, or a combination of at least two thereof.

Preferably, the PBT-PC composite further includes 0.05 to 1.5 parts by weight of an anti-dripping agent, for example, the anti-dripping agent may be 0.1 part, 0.3 part, 0.5 part, 0.8 part, 1 part, 1.2 part or 1.4 part, and specific values therebetween, and the invention is not exhaustive list of the specific values included in the range for brevity and conciseness.

Preferably, the anti-drip agent comprises amorphous Polytetrafluoroethylene (PTFE).

Preferably, the amorphous polytetrafluoroethylene has a particle size of 0.5-300nm, such as 1nm, 5nm, 10nm, 30nm, 50nm, 80nm, 100nm, 120nm, 150nm, 180nm, 200nm, 220nm, 250nm or 280nm, and specific values therebetween, which is not exhaustive for the invention and for the sake of brevity.

Preferably, the PBT-PC composite further includes 0.1-5 parts by weight of a compatibilizer, for example, the compatibilizer can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, or 4.5 parts, and specific points therebetween are not intended to be exhaustive for purposes of brevity and conciseness, and the invention is not intended to be limited to the specific points included in the scope.

Preferably, the compatibilizing agent comprises any one of a vinyl copolymer, a maleic anhydride polymer, or a maleimide polymer, or a combination of at least two thereof.

Preferably, the compatibilizer comprises any one of ethylene-maleic anhydride copolymer, ethylene-acrylate-glycidyl ester copolymer, maleic anhydride, bismaleimide resin, or styrene-maleic anhydride copolymer, or a combination of at least two thereof.

Preferably, the PBT-PC composite material further comprises 0.01-0.05 part of antioxidant in parts by weight, for example, the antioxidant can be 0.015 part, 0.02 part, 0.025 part, 0.03 part, 0.035 part, 0.04 part or 0.045 part, and specific values therebetween are limited by space and for the sake of brevity, and the invention is not exhaustive enumeration of specific values included in the range.

In the invention, the PBT-PC composite material contains an optional antioxidant, the PBT-graphene oxide composite material contains the optional antioxidant, and the two antioxidants have the same selection range.

Preferably, the antioxidant comprises any one of hindered phenol antioxidants, aromatic amine antioxidants, phosphite antioxidants or thioester antioxidants or a combination of at least two of the hindered phenol antioxidants, the aromatic amine antioxidants and the phosphite antioxidants.

Preferably, the antioxidant comprises a primary antioxidant and an optional secondary antioxidant, wherein the primary antioxidant is a hindered phenol antioxidant and/or an aromatic amine antioxidant, and the secondary antioxidant is a phosphite antioxidant and/or a thioester antioxidant.

Preferably, the mass ratio of the primary antioxidant to the secondary antioxidant is 1 (0.2-5), and may be, for example, 1:0.3, 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.2, 1:2.5, 1:2.8, 1:3, 1:3.2, 1:3.5, 1:3.8, 1:4, 1:4.2, 1:4.5, or 1: 4.8.

Preferably, the hindered phenol-based antioxidant includes n-octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, 2, 6-tributyl-4-methylphenol, bis (3, 5-tributyl-4-hydroxyphenyl) sulfide, 2, 6-di-tert-butyl-p-cresol, 1,3, 5-trimethyl-2, 4,6- (3, 5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,3, 5-tris (3, 5-di-tert-butyl-4-hydroxybenzyl) isocyanuric acid, 2' -thiobis (4-methyl-6-tert-butylphenol), diethyleneglycol bis-beta- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, di-tert-butyl-4-hydroxyphenyl) propionate, di-tert-butyl-4-hydroxy-5-methylphenyl) propionate, di-tert-butyl-2, 5-methyl-p-butyl-2-cresol, di-methyl-2, di-ethylene glycol bis-4-hydroxy-4-hydroxybenzyl-4-methyl-p-propionate, di-tert-butyl-4-hydroxy-4-hydroxybenzyl-phenyl-isocyanurate, di-ethyl-2, di-ethyl-2, and di-ethyl-2, or 4, or a, 4,4' -butylidene-bis (2- (1, 1-dimethylethyl) -5-methyl) phenol, octadecyl (3, 5-dibutyl-4-hydroxy-phenylpropionate), pentaerythritol tetrakis (β - (3, 5-tributyl-4-hydroxyphenyl) propionate), or diethylene glycol bis (β - (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate), or a combination of at least two thereof.

Preferably, the aromatic amine-based antioxidant comprises N, N' -bis (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexamethylenediamine (antioxidant 1098).

Preferably, the phosphite antioxidant includes any one or a combination of at least two of tris (2, 4-di-t-butylphenyl) phosphite, bis (2, 4-di-t-butylphenyl) pentaerythritol diphosphite, pentaerythritol distearyl diphosphite or tetrakis (2, 4-di-t-butylphenyl-4, 4' -biphenyl) bisphosphate.

Preferably, the PBT-PC composite further includes 0.5-5 parts by weight of a toughening agent, for example, the toughening agent can be 0.6 parts, 0.8 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific values therebetween, and the invention is not exhaustive and for the sake of brevity.

Preferably, the toughening agent comprises a core-shell copolymer and/or a reactive copolymer, including but not limited to: any one or a combination of at least two of ACR acrylate polymer, MBS, PTW or E-MA-GMA.

Preferably, the toughening agent comprises any one of or a combination of at least two of polyacrylate, polymethyl methacrylate, methyl acrylate-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, ethylene-methyl acrylate-glycidyl methacrylate copolymer, or ethylene-octene copolymer elastomer.

Preferably, the PBT-PC composite further includes 0.01-0.1 parts by weight of a lubricant, for example, the lubricant may be 0.02 parts, 0.03 parts, 0.04 parts, 0.05 parts, 0.06 parts, 0.07 parts, 0.08 parts, or 0.09 parts, and specific values therebetween, and the invention is not exhaustive list of specific values included in the range for brevity and conciseness.

Preferably, the lubricant comprises any one of or a combination of at least two of a polyol ester type lubricant, montan wax, a wax ester, an oxidized PE (polyethylene) wax, a silicone lubricant, ethylene bis stearamide, a stearate, or a stearate ester.

Preferably, the polyol ester based lubricant comprises pentaerythritol stearate and/or sorbitol partial ester.

Preferably, the PBT-PC composite material comprises the following components in parts by weight:

in a second aspect, the present invention provides a process for preparing a PBT-PC composite as described in the first aspect, the process comprising: and mixing the PBT-graphene oxide composite material, PC resin, a flame retardant and glass fiber, and then melting and extruding to obtain the PBT-PC composite material.

Preferably, the melt extrusion temperature is 210-.

Preferably, the melt extrusion is carried out in a screw extruder.

Preferably, the mixing is performed in a blender.

Preferably, the mixing speed is 300-700rpm, for example, 350rpm, 400rpm, 450rpm, 500rpm, 550rpm, 600rpm or 650rpm, and specific values therebetween are limited for brevity and conciseness, and the invention is not exhaustive.

Preferably, the mixed material further comprises any one or a combination of at least two of a transesterification inhibitor, an anti-dripping agent, a compatilizer, an antioxidant, a toughening agent or a lubricant.

Preferably, the PBT-graphene oxide composite material is pre-baked before mixing, and the temperature is 80-120 ℃.

Preferably, the extrusion is followed by the steps of cooling, drying and pelletizing.

In a third aspect, the invention provides a use of the PBT-PC composite material of the first aspect in an engine part, an electric appliance shell or a lamp.

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

in the PBT-PC composite material provided by the invention, the PBT-graphene oxide composite material, the PC resin, the flame retardant and the glass fiber which are specifically composed are compounded, so that the overall comprehensive performance of the composite material is greatly improved, and the PBT-PC composite material is prepared by compounding the PBT-graphene oxide composite material, the PC resin, the flame retardant and the glass fiberThe crystallinity of the PBT-PC composite material is 13-22, the crystallization rate is more than 0.9, even more than or equal to 1.2, and the crystallization performance is obviously improved; meanwhile, the PBT-PC composite material has the Vicat softening temperature higher than 130 ℃, the thermal deformation temperature higher than 85 ℃, even higher than or equal to 100 ℃, and excellent heat resistance; the impact strength of the cantilever beam notch is 90-130J/m, and the impact strength of the simply supported beam notch is more than or equal to 9kJ/m ² The composite material has high impact toughness, good mechanical property, excellent dimensional stability and the warping degree A/D of the composite material is less than or equal to 0.0035, and reaches the flame retardant level of 0.8mm V-0. The invention fundamentally solves the problems of warping and the like caused by nonuniform heating of the PBT, and the provided PBT-PC composite material has excellent crystallization property, heat resistance, impact toughness, dimensional stability and flame retardance, and can fully meet the performance requirements of peripheral parts of electrical equipment and engines on the material.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

The following preparations, examples and comparative examples according to the invention relate to materials comprising:

(1) PBT resin: an intrinsic viscosity of 1.0dL/g, available from Langshen, Germany;

(2) and (3) graphene oxide: 1-5 thin graphene oxide layers with a diameter of 10-200 μm, available from Hexagon materials;

(3) PC resin: bisphenol A polycarbonate with a melt index of 15g/10min at 300 ℃ under 1.2 kg;

(4) the flame retardant is a phosphorus-inorganic compound flame retardant which is prepared by compounding triphenyl phosphate and talcum powder in a mass ratio of 9: 1;

(5) glass fiber: alkali-free glass fiber, commercially available;

(6) ester exchange inhibitor: ammonium phosphite; anti-dripping agent: amorphous polytetrafluoroethylene, commercially available; a compatilizer: maleic anhydride; antioxidant: 2, 6-tributyl-4-methylphenol; a toughening agent: methyl acrylate-butadiene-styrene copolymers (MBS); lubricant: sorbitol partial esters; silane coupling agent: KH 550.

Preparation example 1

A PBT-graphene oxide composite material A1 comprises the following components in parts by weight: 99 parts of PBT resin, 0.5 part of graphene oxide, 0.04 part of silane coupling agent and 0.1 part of antioxidant.

The preparation method of the PBT-graphene oxide composite material A1 is as follows: mixing the PBT resin after drying, the graphene oxide, the silane coupling agent and the antioxidant in a mixer at a high speed according to the formula amount, wherein the rotating speed is 700rpm, and the mixing time is 10min, so that the PBT resin, the graphene oxide, the silane coupling agent and the antioxidant are kept uniform; the mixed materials are added into a double-screw extruder through a main feeding material, and the temperature of each area is as follows: the temperature of the first zone is 215 ℃, the temperature of the second zone is 225 ℃, the temperature of the third zone is 235 ℃, the temperature of the fourth zone is 235 ℃, the temperature of the fifth zone is 235 ℃, the temperature of the sixth zone is 235 ℃, the temperature of the seventh zone is 235 ℃, the temperature of the eighth zone is 230 ℃, the temperature of the ninth zone is 230 ℃, the temperature of the tenth zone is 230 ℃, and the temperature of the eleventh zone is 225 ℃; and the rotating speed of the screw is 600rpm, and the PBT-graphene oxide composite material A1 is obtained by cooling, drying and granulating after extrusion.

Preparation examples 2 to 5

A PBT-graphene oxide composite material, which is respectively marked as A2-A5, is different from the composite material in example 1 only in that the amounts of the components are different, and are specifically shown in Table 1; the kinds of components and the preparation method were the same as in example 1.

Comparative preparation example 1

The PBT master batch D1 is different from the PBT master batch in example 1 only in that graphene oxide is not contained, and other components, the using amount and the preparation method are the same as those of example 1.

TABLE 1

The performance test methods in table 1 are as follows:

(1) impact strength: ASTM 3.2mm notched Izod impact strength, the test ambient temperature is 23 ℃, and the test method is ASTM D256-2010;

(2) degree of crystallinity: testing was performed according to the method in standard ASTM F2625;

(3) heat distortion temperature: testing according to the method in the standard ASTM D648, wherein the parameters are 1.82MPa and 120 ℃/h;

(4) vicat softening temperature: the test was carried out according to the method in standard ASTM D1525, B120.

According to the performance test results in table 1, in the PBT-graphene oxide composite materials provided in preparation examples 1 to 5, graphene oxide and PBT resin in a specific ratio are adsorbed and reacted in the composite process to become heterogeneous nucleation points of PBT, so that crystallization is promoted, and the heat resistance and impact toughness of the materials are improved; however, when the amount of the graphene oxide is large, the crystallization process may be affected, so that the crystallinity of the PBT-graphene oxide composite material is reduced.

Example 1

The PBT-PC composite material comprises the following components in parts by weight:

the preparation method of the PBT-PC composite material comprises the following steps: mixing the PBT-graphene oxide composite material after drying, PC resin, a flame retardant, glass fiber, an ester exchange inhibitor, an anti-dripping agent, a compatilizer, an antioxidant, a toughening agent and a lubricant in a mixer according to the formula amount, wherein the mixing speed is 500rpm, and the mixing time is 15 min; the mixed materials were fed into a twin screw extruder, the temperatures in the zones being set as follows: the temperature of the first zone is 220 ℃, the temperature of the second zone is 230 ℃, the temperature of the third zone is 240 ℃, the temperature of the fourth zone is 240 ℃, the temperature of the fifth zone is 240 ℃, the temperature of the sixth zone is 240 ℃, the temperature of the seventh zone is 240 ℃, the temperature of the eighth zone is 235 ℃, the temperature of the ninth zone is 235 ℃, the temperature of the tenth zone is 235 ℃, and the temperature of the eleventh zone is 230 ℃; the rotating speed of the screw is 550rpm, and the PBT-PC composite material is obtained after extrusion, cooling, drying and grain cutting.

Examples 2 to 20, comparative examples 1 to 5

PBT-PC composites were prepared in the amounts (in parts) shown in tables 2, 3, 4 and 5.

TABLE 2

TABLE 3

TABLE 4

In table 4, the PBT-graphene oxide composites in examples 15 to 17 were PBT-graphene oxide composites a2, and the PBT-graphene oxide composites in examples 18 to 20 were PBT-graphene oxide composites A3, respectively.

TABLE 5

The performance test methods in tables 2-5 are as follows:

(1) notched izod impact strength: ASTM 3.2mm notched Izod impact strength, test environment temperature 23 ℃, test method ASTM D256-2010;

(2) impact strength of the simply supported beam notch: the test was carried out according to the method in ISO 179-1993, with an ambient temperature of 23 ℃;

(3) heat distortion temperature: ISO heat distortion temperature, tested according to the method in the standard ASTM D648, 1.82MPa, 120 ℃/h;

(4) vicat softening temperature: ISO vicat softening temperature, measured according to the method in standard ASTM D1525, B120;

(5) flame retardancy: flame retardancy of 0.8mm and 1.6mm was measured according to UL94 method;

(6) degree of crystallization and crystallization rate: testing was performed according to the method in standard ASTM F2625;

(7) warping degree A/D: the warping degree of the material is represented by the ratio of the maximum height A to the diameter D of the circular plate, and the samples are stored at the normal temperature of 23 ℃ for 24 hours and then tested.

As can be seen from the data in tables 2, 3, 4 and 5, compared with the comparative examples 1 to 4 containing no graphene oxide, the PBT-PC composite materials provided in examples 1 to 14 of the present invention were prepared by compounding the PBT-graphene oxide composite material having specific components, the PC resin, the flame retardant, the glass fiber and other additives, so that the notched Izod impact strength of the PBT-PC composite material was 90 to 130J/m, and the notched Izod impact strength of the simply-braced beam was 9 to 13.5kJ/m ² The thermal deformation temperature is more than or equal to 85 ℃, the temperature can reach 100-150 ℃, the Vicat softening temperature is more than 110 ℃, even more than 130 ℃, the temperature can reach 132-187 ℃, the crystallinity is 13-22, the crystallization rate is more than 0.9 and can be 1.2-1.6, the warpage A/D of the composite material is as low as 0.001-0.0035, the composite material has excellent crystallization property, heat resistance, impact toughness, dimensional stability and flame retardance, and the problems of warpage and the like caused by nonuniform heating of PBT are solved. Meanwhile, the combination of the components and the performances of the PBT-PC composite material in the embodiments 1 to 14 shows that the combination property of the PBT-PC composite material can be more optimized by adjusting the dosage of each component.

In the PBT-PC composite material provided by the invention, the PBT resin and the graphene oxide are compounded at first, the PBT-graphene oxide composite material is formed through a melt blending reaction, and the PBT-graphene oxide composite material is further compounded with the PC resin, the flame retardant, the glass fiber and other components, so that the temperature conduction rate of the whole material is accelerated, uniform crystallization is promoted, the ester exchange reaction of the PBT and the PC is inhibited, the migration of the flame retardant is prevented, and the crystallinity, the heat resistance, the impact toughness, the size stability and the flame retardance of the PBT-PC composite material are greatly improved. In comparative examples 5 and 6, graphene oxide GO is directly added, and is not compounded with PBT resin, and is separately melt-blended with PBT master batches, PC resin, glass fiber and other components in a filler form, so that the PBT master batches cannot be in complete contact with PBT materials, the number of the constructed nucleation points is limited, the crystallinity of the PBT cannot be improved, and the active reaction groups of ester groups in the PBT structure cannot be consumed, so that the PBT master batches cannot be subjected to transesterification reaction with PC, and the obtained composite materials have poor crystallinity, low heat distortion and Vicat softening point temperatures and high warping degree A/D values.

The applicant states that the invention is illustrated by the above examples to the PBT-PC composite material of the invention, the preparation method and the application thereof, but the invention is not limited by the above examples, i.e. the invention is not meant to be implemented only by relying on the above examples. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims

1. The PBT-PC composite material is characterized by comprising the following components in parts by weight:

2. The PBT-PC composite of claim 1, wherein the PBT resin has an intrinsic viscosity of 0.5 to 2.5 dL/g;

preferably, the sheet diameter of the graphene oxide is 10-200 μm;

preferably, the PBT-graphene oxide composite material further comprises 0.01-5 parts by weight of a coupling agent;

preferably, the coupling agent comprises a silane coupling agent;

preferably, the PBT-graphene oxide composite material further comprises 0.01-0.5 part of antioxidant in parts by weight.

3. The PBT-PC composite of claim 1 or 2, wherein the PBT-graphene oxide composite is prepared by a process comprising: mixing PBT resin with graphene oxide, reacting and extruding to obtain the PBT-graphene oxide composite material;

preferably, the temperature of the reaction is 210-250 ℃;

preferably, the reaction is carried out in a screw extruder;

preferably, the screw rotation speed of the screw extruder is 350-750 rpm.

4. The PBT-PC composite of any of claims 1-3, wherein the PC resin comprises a bisphenol A polycarbonate;

preferably, the PC resin has a melt index of 5-40g/10min at 300 ℃ under 1.2 kg;

preferably, the mass ratio of the PC resin to the PBT-graphene oxide composite material is 1 (1.5-2.5).

5. The PBT-PC composite of any one of claims 1-4, wherein the flame retardant comprises a phosphorus-based flame retardant;

preferably, the phosphorus-based flame retardant comprises any one of resorcinol bis (phenyl phosphate), bisphenol a bis (diphenyl phosphate), tris (2, 2-dibromomethyl-3-bromopropyl phosphonate), ammonium polyphosphate, aluminum phosphinate, pentaerythritol phosphate, triphenyl phosphate, tricresyl phosphate, tris (2, 6-dimethylphenyl) phosphine, brominated aromatic phosphate, red phosphorus, or a phosphorus-nitrogen complex flame retardant, or a combination of at least two thereof;

preferably, the flame retardant further comprises an inorganic filler flame retardant;

preferably, the inorganic filler flame retardant comprises any one or a combination of at least two of talcum powder, calcium carbonate, mica, silica lime, glass beads, montmorillonite, kaolin, aluminum hydroxide or magnesium hydroxide;

preferably, the flame retardant comprises a combination of a phosphorus flame retardant and an inorganic filler flame retardant, and the mass ratio of the phosphorus flame retardant to the inorganic filler flame retardant is (1-10): 1.

6. The PBT-PC composite of any one of claims 1 to 5, further comprising 0.01 to 0.5 parts by weight of a transesterification inhibitor;

preferably, the transesterification inhibitor comprises any one of sodium dihydrogen phosphate, ammonium hypophosphite, sodium acid pyrophosphate, ammonium phosphite, triphenyl phosphite or triphenyl phosphate or a combination of at least two of the above;

preferably, the PBT-PC composite material also comprises 0.05 to 1.5 parts by weight of anti-dripping agent;

preferably, the anti-drip agent comprises amorphous polytetrafluoroethylene;

preferably, the grain size of the amorphous polytetrafluoroethylene is 0.5-300 nm;

preferably, the PBT-PC composite material also comprises 0.1-5 parts of a compatilizer in parts by weight;

7. The PBT-PC composite of any one of claims 1 to 6, further comprising 0.01 to 0.05 parts by weight of an antioxidant;

preferably, the antioxidant comprises any one of or a combination of at least two of hindered phenol antioxidants, aromatic amine antioxidants, phosphite antioxidants or thioester antioxidants;

preferably, the antioxidant comprises a primary antioxidant and an optional secondary antioxidant, wherein the primary antioxidant is a hindered phenol antioxidant and/or an aromatic amine antioxidant, and the secondary antioxidant is a phosphite antioxidant and/or a thioester antioxidant;

preferably, the mass ratio of the main antioxidant to the auxiliary antioxidant is 1 (0.2-5);

preferably, the PBT-PC composite material also comprises 0.5-5 parts of a toughening agent in parts by weight;

preferably, the toughening agent comprises any one of or a combination of at least two of polyacrylate, polymethyl methacrylate, methyl acrylate-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, ethylene-methyl acrylate-glycidyl methacrylate copolymer or ethylene-octene copolymer elastomer;

preferably, the PBT-PC composite material also comprises 0.01 to 0.1 part of lubricant in parts by weight;

preferably, the lubricant comprises any one of or a combination of at least two of a polyol ester lubricant, montan wax, a wax ester, an oxidized PE wax, a silicone lubricant, ethylene bis stearamide, a stearate, or a stearate ester.

8. A process for the preparation of a PBT-PC composite according to any one of claims 1 to 7, wherein the process comprises: and mixing the PBT-graphene oxide composite material, PC resin, a flame retardant and glass fiber, and then carrying out melt extrusion to obtain the PBT-PC composite material.

9. The method as claimed in claim 8, wherein the temperature of the melt extrusion is 210-250 ℃;

preferably, the melt extrusion is carried out in a screw extruder;

preferably, the screw rotating speed of the screw extruder is 350-750 rpm;

10. Use of a PBT-PC composite according to any of claims 1-7 in an engine part, an electrical housing or a luminaire.