CN114605805A

CN114605805A - Flame-retardant polycarbonate composition and preparation method thereof

Info

Publication number: CN114605805A
Application number: CN202210399952.XA
Authority: CN
Inventors: 何彬; 何继辉
Original assignee: Guangdong Aldex New Material Co Ltd
Current assignee: Guangdong Aldex New Material Co Ltd
Priority date: 2022-04-15
Filing date: 2022-04-15
Publication date: 2022-06-10
Anticipated expiration: 2042-04-15
Also published as: CN114605805B

Abstract

The invention discloses a flame-retardant polycarbonate composition and a preparation method thereof, wherein the flame-retardant polycarbonate composition is prepared from polycarbonate resin, polysiloxane-polycarbonate copolymer, acrylonitrile-butadiene-styrene copolymer, bisphenol A bis (diphenyl phosphate), an organic silicon flame-retardant synergist, methyl methacrylate-styrene-organic silicon copolymer, styrene-acrylonitrile-glycidyl methacrylate copolymer, hindered phenol antioxidant, phosphite antioxidant, pentaerythritol stearate and modified polytetrafluoroethylene, wherein the total weight of the polycarbonate resin, the polysiloxane-polycarbonate and the acrylonitrile-butadiene-styrene copolymer is 100 parts; the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 2.5-24: 1. The raw material components are matched with each other, so that the flame-retardant polycarbonate composition has excellent flame retardant property, mechanical property, processing property, chemical resistance and antibacterial property.

Description

Flame-retardant polycarbonate composition and preparation method thereof

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to a flame-retardant polycarbonate composition and a preparation method thereof.

Background

With the development of the medical industry in the world more and more rapidly, the traditional materials show fatigue gradually, and the requirements of modern medical instruments on high strength, high precision and high durability are more and more difficult to meet. The polycarbonate PC serving as an engineering plastic with wide application has excellent performances such as high strength, high impact resistance, high and low temperature resistance and the like, and can be widely applied to the fields of aerospace, automobile interior and exterior decoration, electronic products, household appliances, food, medical appliances and the like. In addition, the PC product can be sterilized by light irradiation, high-temperature high-pressure steam and other modes, the performance of the PC product can not be reduced due to the environmental influence in the sterilization process, and the PC product is widely applied to high-pressure injectors, hemodialyzers, shell operation masks, disposable medical consumables, minimally invasive surgical instruments such as laparoscopes and the like due to the characteristics of transparency, no toxicity, no smell, difficult pollution, good heat resistance, good drug resistance and the like, and particularly has application in the manufacture of artificial lung tissues and artificial kidney organs.

Although PC materials have excellent material properties that cannot be compared with other engineering plastics, PC also has the defect that stress cracking is easily generated. The reason for stress cracking is that during the injection molding process, because the melt viscosity of the PC material is high and the rigidity of the molecular chain is relatively high, a high degree of elastic deformation is generated and cannot be released to be retained in the product, which forms internal stress. When the internal stress is induced by external factors, the energy of elastic deformation needs to be released, and when the energy is greater than the tearing resistance of a PC molecular chain product, the balance in the product is broken, namely, stress cracking is generated. In order to reduce the problems of large internal stress and poor flowability of PC, an ABS material is added into PC resin to reduce the melt temperature and the internal stress of the material.

The flame retardants commonly used in PC materials at present are mainly halogen-based, phosphorus-based and some inorganic flame retardants. Because the material performance and the environmental protection requirement are more and more strict, some halogen-containing flame retardants can not meet the environmental protection requirement in practical application, the promotion of the inorganic flame retardants to the flame-retardant upper limit of the material is limited, and although the phosphorus flame retardants effectively solve the problems of the two, the phosphorus flame retardants have larger dosage and larger damage to the mechanical properties of the material under the same flame-retardant condition due to the poor flame-retardant efficiency. The organic silicon flame-retardant synergist is a novel non-halogen char-forming type flame-retardant synergist which is efficient and eco-friendly and has little smoke suppression, and the problem of large using amount of phosphorus flame retardants can be improved in a limited way by compounding the rest phosphorus flame retardants.

In recent years, the stress resistance of polycarbonate is improved at home and abroad, a methyl methacrylate-styrene-butadiene copolymer and a copolymer of styrene and glycidyl methacrylate are generally selected for synergistic toughening, but the addition of a large amount of toughening agent can increase the processing temperature of a PC material, reduce the fluidity and reduce the flame retardant property. At present, polytrimethylene polycarbonate in the prior art has poor flame retardance and processability, and some patents make some researches on practical application systems of flame retardant polycarbonate for medical use to improve the difficult-to-process characteristics of the flame retardant polycarbonate, such as: chinese patent CN107227012A discloses a medical flame-retardant and easily-formed polycarbonate material and a preparation method thereof, the invention firstly adopts zinc oxide and boric acid as reaction raw materials, ammonium persulfate is used as an initiator, the zinc oxide and the zinc borate generated by the boric acid have good flame retardance and play a good synergistic effect with hexachlorocyclotriphosphazene, then the obtained polymer is subjected to electrostatic spinning to obtain flame-retardant fibers, and then the flame-retardant fibers are subjected to hydroxylation and amination reaction, finally polyamide is grafted on the surface of the flame-retardant fibers, and then the flame-retardant fibers are mixed with a carbonate monomer to participate in carbonate polymerization reaction to obtain the polycarbonate material with good flame retardance and high mechanical strength; chinese patent CN 107325513A discloses a nano-silver deposition medical bacteriostatic polycarbonate material, which is composed of the following raw materials in parts by weight: 50-75 parts of polycarbonate, 20-25 parts of initiator solution, 10-15 parts of polyvinylpyrrolidone, 10-15 parts of acrylonitrile, 0.5-1 part of chitosan and 0.5-1 part of potassium sorbate; the invention mainly focuses on improving the bacteriostatic effect of polycarbonate, and has the defects of unobvious improvement on the flame retardant effect and the chemical resistance reagent effect and difficult injection molding in the processing process; chinese patent CN 107164824A discloses a medical sol type polycarbonate material with high antibacterial activity, which is composed of the following raw materials in parts by weight: 40-50 parts of polytrimethylene carbonate, 40-50 parts of bacteriostatic agent, 8-12 parts of titanyl sulfate, 5-8 parts of acrylonitrile, 0.5-1 part of methyl nylon acid ester and 0.05-0.1 part of 8-hydroxyquinoline; the invention mainly improves the antibacterial property of the polycarbonate material by adopting a physical modification method, but the modified polycarbonate material has high processing temperature and insufficient fluidity and cannot be better applied to large-scale parts.

Disclosure of Invention

Based on the above, one of the objectives of the present invention is to provide a flame retardant polycarbonate composition, which has good flame retardant properties, excellent mechanical properties, flowability, and organic solvent resistance, and can be applied in the industries of medical devices and the like.

The specific technical scheme for realizing the aim of the invention comprises the following steps:

the flame-retardant polycarbonate composition is prepared from the following raw materials in parts by weight:

wherein the total of the parts by weight of the polycarbonate resin, the polysiloxane-polycarbonate and the acrylonitrile-butadiene-styrene copolymer is 100 parts; the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 2.5-24: 1.

In some embodiments, the flame retardant polycarbonate composition is prepared from the following raw materials in parts by weight:

the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 4-10: 1.

In some embodiments, the polycarbonate composition is prepared from the following raw materials in parts by weight:

the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 4-5: 1.

In some embodiments, the styrene-acrylonitrile-glycidyl methacrylate copolymer is a reactive compatibilizer, wherein the mass fraction of glycidyl methacrylate is 2 wt% to 4 wt%.

In some of these embodiments, the melt index of the polycarbonate resin is 10g/10min to 12g/10 min.

In some of these embodiments, the polysiloxane-polycarbonate copolymer has a melt index of 3g/10min to 10g/10min and a siloxane content of 6 wt% to 14 wt%.

In some of these embodiments, the hindered phenolic antioxidant is octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, and/or the phosphite antioxidant is bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate.

In some of these embodiments, the silicone flame retardant synergist is FAC-107 and/or STR-100.

In some of these embodiments, the antimicrobial agent is an Ag-based carrier-based inorganic antimicrobial agent.

Another object of the present invention is to provide a method for preparing the above flame retardant polycarbonate composition.

a method of making a flame retardant polycarbonate composition, comprising the steps of:

(1) mixing the dried polycarbonate resin, polysiloxane-polycarbonate copolymer, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-styrene-organic silicon copolymer and styrene-acrylonitrile-glycidyl methacrylate copolymer;

(2) mixing bisphenol A bis (diphenyl phosphate), an organic silicon flame-retardant synergist, a hindered phenol antioxidant, a phosphite antioxidant, pentaerythritol stearate and modified polytetrafluoroethylene and an antibacterial agent;

(3) mixing the mixed material obtained in the step (1) with the mixed material obtained in the step (2);

(4) and (4) adding the mixture mixed in the step (3) into a parallel double-screw extruder through a feeder, and performing melt extrusion granulation in the parallel double-screw extruder to obtain the composite material.

In some of these embodiments, the process parameters for melt extrusion granulation include: the temperature of the first zone is 210-240 ℃, the temperature of the second zone is 230-260 ℃, the temperature of the third zone is 235-260 ℃, the temperature of the fourth zone is 220-260 ℃, the temperature of the fifth zone is 220-260 ℃, the temperature of the sixth zone is 220-260 ℃, the temperature of the seventh zone is 220-260 ℃, the temperature of the eighth zone is 220-260 ℃, the temperature of the die head is 240-275 ℃, and the rotating speed of the screw is 200-600 rpm.

In some of these embodiments, the process parameters for melt extrusion granulation include: the temperature of the first zone is 225-235 ℃, the temperature of the second zone is 235-245 ℃, the temperature of the third zone is 245-255 ℃, the temperature of the fourth zone is 245-255 ℃, the temperature of the fifth zone is 245-255 ℃, the temperature of the sixth zone is 245-255 ℃, the temperature of the seventh zone is 240-250 ℃, the temperature of the eighth zone is 240-250 ℃, the temperature of the die head is 255-265 ℃ and the rotating speed of the screw is 350-500 rpm.

In some of these embodiments, the drying conditions in step (1) comprise: the temperature is 80-110 ℃, and the time is 4-8 hours.

In some embodiments, the drying conditions in step (1) comprise: the temperature is 100-110 ℃, and the time is 4-6 hours.

In some of these embodiments, the mixing in step (1) is carried out at a stirring speed of 400 rpm to 600 rpm.

In some of these embodiments, the mixing in step (2) is performed at a stirring speed of 400 rpm to 600 rpm.

In some embodiments, the mixing in step (3) is performed at a stirring speed of 400 rpm to 600rpm for 8min to 12 min.

In some of these embodiments, the screw shape of the parallel twin screw extruder is a single flight.

In some of the embodiments, the ratio L/D of the length L and the diameter D of the screw of the parallel double-screw extruder is 35-50; the screw is provided with more than 1 meshing block area and more than 1 reverse thread area.

In some of these embodiments, the ratio L/D of the length L of the screw to the diameter D of the screw is 35 to 45; and 2 meshing block areas and 1 reverse thread area are arranged on the screw rod.

The flame-retardant polycarbonate composition and the preparation method thereof have the following principles:

different from the traditional bromine antimony flame retardant, the environment-friendly halogen-free flame retardant bisphenol A bis (diphenyl phosphate) and the organic silicon flame retardant synergist are selected for compounding, the bisphenol A bis (diphenyl phosphate) belongs to a flame retardant plasticizer and has better capability of improving the flame retardant effect of the polycarbonate composition, but the bisphenol A bis (diphenyl phosphate) can enable the material to reach V0 only under the condition of larger using amount, and the excessive addition of the bisphenol A bis (diphenyl phosphate) can greatly improve the fluidity of the material and simultaneously reduce the toughness; the organic silicon flame-retardant synergist belongs to a siloxane grafted flaky solid flame retardant, the flame retardance of PC is improved, meanwhile, negative effects on other performances are hardly generated, and organic silicon molecules can accelerate the surface of the polycarbonate composition to be carbonized, so that the release of smoke is reduced. Compared with the traditional methyl methacrylate-styrene-butadiene copolymer, the methyl methacrylate-styrene-organosilicon copolymer has the advantages that the organosilicon is used for replacing butadiene, so that the weather resistance and the impact resistance of the material can be effectively improved, the polycarbonate composition has higher toughness and chemical resistance, the material can be applied to a harsher environment for a long time, and the performance retention rate is not reduced. In addition, the Si-O-Si bond on the main chain of the methyl methacrylate-styrene-organic silicon copolymer is easier to graft with a PC matrix under the action of the styrene-acrylonitrile-glycidyl methacrylate copolymer, so that the flame retardance of the PC matrix is effectively improved, and the styrene-acrylonitrile-glycidyl methacrylate copolymer (SAG-001) is used as a compatilizer and an interface improver to solve the problems of difficult compounding and difficult uniform dispersion when the methyl methacrylate-styrene-organic silicon copolymer is added into the PC in a physically mixed form, so that the compatibility of each component in the formula is improved, the integral fluidity of the material is increased, and the performances after melt blending are more excellent.

The antioxidant is beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate, the thermal stability of the antioxidant in the blending process of the polycarbonate composition is good, and the hindered piperidyl of the antioxidant can provide an antioxidant effect and improve the dyeability of the copolymer; the melting point of bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate is 239 ℃, the thermal decomposition temperature exceeds 350 ℃, and the bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate has good heat resistance and hydrolysis resistance and can be modifiedThe polycarbonate material provides excellent color stability and melt stability during high-speed blending, while preventing thermal degradation of polycarbonate, flame retardant and other small-molecular auxiliary agents during high temperature, and suppressing thermal oxidative discoloration due to long-term exposure, and also provides a method for producing the same_x) Color stability in gas environment, and prevention of discoloration due to fumigation. The Ag-series carrier inorganic antibacterial agent is selected, so that the heat-resistant stability is stronger, the propagation of bacteria on the surface of a workpiece can be effectively inhibited, and the antibacterial efficiency can reach 99.99%.

The pentaerythritol stearate has the effects of improving the stripping performance of the material and increasing the thermal stability, and when the pentaerythritol stearate is independently used as a lubricant, the shearing force of the screw on the material can be effectively weakened, and the performance damage of the material subjected to physical shearing can be reduced.

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

1. according to the invention, the phosphate flame retardant bisphenol A bis (diphenyl phosphate) and the organic silicon flame retardant synergist are compounded, so that the processing melt temperature of the polycarbonate composition is effectively reduced, and the processing fluidity is improved; the comprehensive performance of the polycarbonate composition is improved by adding polysiloxane-polycarbonate copolymer, methyl methacrylate-styrene-organosilicon copolymer and reaction type compatilizer styrene-acrylonitrile-glycidyl methacrylate copolymer, and the internal stress of the PC material is reduced by introducing a large amount of siloxane graft, and the notch sensitivity and the thick wall brittleness of the PC material are improved at the same time. Meanwhile, the addition of a small amount of acrylonitrile-butadiene-styrene copolymer greatly reduces the overall processing temperature of the material on the basis of further reducing the internal stress of the PC resin, so that the improved polycarbonate composition has better processability. The raw material components are matched with each other, so that the obtained flame-retardant polycarbonate composition has excellent flame retardant property, mechanical property, processability, chemical resistance and antibacterial property, and is suitable for medical products.

2. The preparation method of the flame-retardant polycarbonate composition provided by the invention has the advantages of simple process, easiness in control and low requirements on equipment, and the used equipment is general polymer processing equipment, so that the investment is low, and the industrial production is facilitated.

Drawings

FIG. 1 is a flow chart of a process for preparing a flame retardant polycarbonate composition of the present invention.

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 examples of the invention and the comparative examples used the following raw materials:

polycarbonate resin with weight-average molecular weight of 17000-19000 and melt index of 10g/10min, selected from the group consisting of Japanese emperor Co;

a polysiloxane-polycarbonate copolymer with a weight-average molecular weight of 21000-23000, a melt index of 3.5g/10min and a siloxane content of 14 wt%; selected from Korea Sanyangtai Co Ltd;

bisphenol a bis (diphenyl phosphate) selected from shanghai kunjin chemical company ltd;

an organosilicon flame-retardant synergist FCA-107 selected from Corning, Inc., USA;

a methyl methacrylate-styrene-silicone copolymer selected from mitsubishi corporation;

styrene-acrylonitrile-glycidyl methacrylate copolymer, the mass fraction of Glycidyl Methacrylate (GMA) being 3 wt%, selected from sigma aldrich (shanghai) trade ltd;

octadecyl-beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, selected, for example, from Pasteur GmbH, Germany;

bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate selected from Shanghai Yaozao Fine chemical Co., Ltd;

pentaerythritol stearate selected from chemical industry, Inc. of Sendeli, Zhaoqing;

modified polytetrafluoroethylene, type: SN3300B7 selected from Guangzhou entropy energy Innovation materials GmbH;

antibacterial BM-102SD selected from Fuyu corporation of Japan.

The poly-spiro-phosphate diamide is selected from Yino chemical technology, Inc., Guangzhou city;

a methyl methacrylate-styrene-butadiene copolymer selected from the group consisting of koilou, japan;

styrene maleic anhydride copolymer selected from Dongguan raw chemical Co., Ltd;

the present invention will be described in detail with reference to specific examples.

Example 1A flame retardant polycarbonate composition and method of making the same

The flame-retardant polycarbonate composition of the embodiment is prepared from the following raw materials in parts by weight:

the method for preparing the flame retardant polycarbonate composition of the embodiment comprises the following steps:

(1) the polycarbonate resin, the polysiloxane-polycarbonate copolymer and the acrylonitrile-butadiene-styrene copolymer are dried at the temperature of 100 ℃ for 4 hours, cooled and added into a stirrer (the rotating speed is 500 revolutions per minute) together with the methyl methacrylate-styrene-organosilicon copolymer and the styrene-acrylonitrile-glycidyl methacrylate copolymer for mixing.

(2) Adding bisphenol A bis (diphenyl phosphate), an organosilicon flame-retardant synergist, beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate, bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate, pentaerythritol stearate, modified polytetrafluoroethylene and an antibacterial agent into another stirrer (the rotating speed is 500 revolutions per minute) for mixing.

(3) And (3) pouring the mixed materials obtained in the steps (1) and (2) into the same high-speed stirrer (the rotating speed is 500 revolutions per minute) and mixing for 10 min.

(4) Adding the mixture mixed in the step (3) into a parallel double-screw extruder through a feeder, and performing melt extrusion granulation in the parallel double-screw extruder (total eight zones), wherein the process parameters comprise: the temperature of the first zone is 230 ℃, the temperature of the second zone is 240 ℃, the temperature of the third zone is 250 ℃, the temperature of the fourth zone is 250 ℃, the temperature of the fifth zone is 250 ℃, the temperature of the sixth zone is 250 ℃, the temperature of the seventh zone is 245 ℃, the temperature of the eighth zone is 245 ℃, the temperature of the die head is 260 ℃ and the rotating speed of the screw is 500 rpm; the screw of the parallel double-screw extruder is in a single-thread shape, the ratio L/D of the length L and the diameter D of the screw is 35, and the screw is provided with 2 meshing block areas and 1 back-thread area.

Example 2A flame retardant polycarbonate composition and method of making the same

(3) And (3) pouring the mixed materials obtained in the step (1) and the step (2) into the same high-speed stirrer (the rotating speed is 500 revolutions per minute), and mixing for 10 min.

Example 3A flame retardant polycarbonate composition and method of making the same

Example 4A flame retardant polycarbonate composition and method of making the same

(4) Adding the mixture mixed in the step (3) into a parallel double-screw extruder through a feeder, and performing melt extrusion granulation in the parallel double-screw extruder (total eight zones), wherein the process parameters comprise: the temperature of the first zone is 230 ℃, the temperature of the second zone is 240 ℃, the temperature of the third zone is 250 ℃, the temperature of the fourth zone is 250 ℃, the temperature of the fifth zone is 250 ℃, the temperature of the sixth zone is 250 ℃, the temperature of the seventh zone is 245 ℃, the temperature of the eighth zone is 245 ℃, the temperature of the die head is 260 ℃ and the rotation speed of the screw is 500 rpm; the screw of the parallel double-screw extruder is in a single-thread shape, the ratio L/D of the length L and the diameter D of the screw is 35, and the screw is provided with 2 meshing block areas and 1 back-thread area.

Example 5A flame retardant polycarbonate composition and method of making the same

Example 6A flame retardant polycarbonate composition and method of making the same

(1) and drying the polycarbonate resin, the polysiloxane-polycarbonate copolymer and the acrylonitrile-butadiene-styrene copolymer at the temperature of 100 ℃, cooling the dried products after 4 hours, and adding the cooled products, the methyl methacrylate-styrene-organosilicon copolymer and the styrene-acrylonitrile-glycidyl methacrylate copolymer into a stirrer (the rotating speed is 500 revolutions per minute) for mixing.

Example 7A flame retardant polycarbonate composition and method of making the same

Example 8A flame retardant polycarbonate composition and method of making the same

(4) Adding the mixture mixed in the step (3) into a parallel double-screw extruder through a feeder, and performing melt extrusion granulation in the parallel double-screw extruder (total eight zones), wherein the process parameters comprise: the temperature of the first zone is 230 ℃, the temperature of the second zone is 240 ℃, the temperature of the third zone is 250 ℃, the temperature of the fourth zone is 250 ℃, the temperature of the fifth zone is 250 ℃, the temperature of the sixth zone is 250 ℃, the temperature of the seventh zone is 245 ℃, the temperature of the eighth zone is 245 ℃, the temperature of the die head is 260 ℃ and the rotating speed of the screw is 500 rpm; the shape of a screw of the parallel double-screw extruder is double-thread, the ratio L/D of the length L and the diameter D of the screw is 50, and the screw is provided with 2 meshing block areas and 1 back-thread area.

Comparative example 1 a flame retardant polycarbonate composition and a method for preparing the same

The flame-retardant polycarbonate composition of the comparative example is prepared from the following raw materials in parts by weight:

the method of preparing the flame retardant polycarbonate composition of this comparative example comprises the steps of:

(2) Adding bisphenol A bis (diphenyl phosphate), beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate, bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate, pentaerythritol stearate, modified polytetrafluoroethylene and an antibacterial agent into another stirrer (the rotating speed is 500 r/min) for mixing.

Comparative example 2 flame retardant polycarbonate composition and preparation method thereof

(2) Adding the organosilicon flame-retardant synergist, beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) octadecyl propionate, bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate, pentaerythritol stearate, modified polytetrafluoroethylene and an antibacterial agent into another stirrer (the rotating speed is 500 revolutions per minute) for mixing.

Comparative example 3a flame retardant polycarbonate composition and method for preparing the same

the method of making the flame retardant polycarbonate composition of this comparative example comprises the steps of:

(1) and drying the polycarbonate resin and the acrylonitrile-butadiene-styrene copolymer at the temperature of 100 ℃, cooling after 4 hours, adding the polycarbonate resin and the acrylonitrile-butadiene-styrene copolymer into a stirrer (the rotating speed is 500 revolutions per minute) together with the methyl methacrylate-styrene-organosilicon copolymer and the styrene-acrylonitrile-glycidyl methacrylate copolymer for mixing.

Comparative example 4a flame retardant polycarbonate composition and a method for preparing the same

(1) the polysiloxane-polycarbonate copolymer and the acrylonitrile-butadiene-styrene copolymer are dried at the temperature of 100 ℃ for 4 hours, cooled and added into a stirrer (the rotating speed is 500 revolutions per minute) together with the methyl methacrylate-styrene-organosilicon copolymer and the styrene-acrylonitrile-glycidyl methacrylate copolymer for mixing.

Comparative example 5 a flame retardant polycarbonate composition and a method for preparing the same

the method of making the polycarbonate composition of this comparative example comprises the steps of:

Comparative example 6 a flame retardant polycarbonate composition and a method for preparing the same

Comparative example 7 flame retardant polycarbonate composition and method for preparing the same

(2) Adding bisphenol A bis (diphenyl phosphate), polyspiro phosphate diamide, beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid octadecyl ester, bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate, pentaerythritol stearate, modified polytetrafluoroethylene and an antibacterial agent into another stirrer (the rotating speed is 500 revolutions per minute) for mixing.

(4) Adding the mixture mixed in the step (3) into a parallel double-screw extruder through a feeder, and performing melt extrusion granulation in the parallel double-screw extruder (total eight zones), wherein the process parameters comprise: the temperature of the first zone is 230 ℃, the temperature of the second zone is 240 ℃, the temperature of the third zone is 250 ℃, the temperature of the fourth zone is 250 ℃, the temperature of the fifth zone is 250 ℃, the temperature of the sixth zone is 250 ℃, the temperature of the seventh zone is 245 ℃, the temperature of the eighth zone is 245 ℃, the temperature of the die head is 260 ℃ and the rotating speed of the screw is 500 rpm; the shape of a screw of the parallel double-screw extruder is a single thread, the ratio L/D of the length L and the diameter D of the screw is 35, and the screw is provided with 2 meshing block areas and 1 reverse thread area.

Comparative example 8A flame retardant polycarbonate composition and method for preparing the same

(1) the polycarbonate resin, the polysiloxane-polycarbonate copolymer and the acrylonitrile-butadiene-styrene copolymer were dried at 100 ℃ for 4 hours, cooled, and mixed with the methyl methacrylate-styrene-butadiene copolymer and the styrene-acrylonitrile-glycidyl methacrylate copolymer in a mixer (at 500 rpm).

Comparative example 9 a flame retardant polycarbonate composition and method of making the same

(1) and drying the polycarbonate resin, the polysiloxane-polycarbonate copolymer and the acrylonitrile-butadiene-styrene copolymer at the temperature of 100 ℃, cooling after 4 hours, adding the polycarbonate resin, the polysiloxane-polycarbonate copolymer and the acrylonitrile-butadiene-styrene copolymer into a stirrer (the rotating speed is 500 revolutions per minute) together with the methyl methacrylate-styrene-organosilicon copolymer and the styrene maleic anhydride copolymer, and mixing.

TABLE 1 summary of the composition parts by weight of the raw materials of the examples and comparative examples

Note: a, changing a screw structure; PC is a polycarbonate resin; Si-PC is a polysiloxane-polycarbonate copolymer; ABS is an acrylonitrile-butadiene-styrene copolymer; BDP is bisphenol a bis (diphenyl phosphate); s-2001 is a methyl methacrylate-styrene-silicone copolymer; SAG-001 is a styrene-acrylonitrile-glycidyl methacrylate copolymer. A is polyspirocyclic phosphate diamide; b is methyl methacrylate-styrene-butadiene copolymer; c is styrene maleic anhydride copolymer.

The polycarbonate compositions prepared in the above examples and comparative examples were subjected to the following property tests:

flame retardant property: the test was carried out according to UL-94 standard, and the specimens had a thickness of 0.7 mm.

Melt index: the test temperature is 260 ℃ and the load is 2.16kg according to the test of GB/T3682-2000-plus-2000 standard.

And (3) solvent resistance test: preparing 0.25-0.33 wt% of benzethonium chloride and 15-18 wt% of isopropanol solution, covering the surface of the sample strip in a stressed state after soaking the sample strip in a paper towel, and recording the breaking time (h) of the sample strip, wherein the higher the value, the better the value.

Impact properties: the thickness of the sample strip is 4mm according to GB/T1843-2008 standard test, and the higher the value, the better the value.

The results of the performance tests are shown in table 2.

TABLE 2 Properties of the polycarbonate compositions of the examples and comparative examples

Examples 1 to 7 are polycarbonate compositions prepared by adjusting the amounts of polycarbonate, polysiloxane-polycarbonate copolymer, acrylonitrile-butadiene-styrene copolymer, bisphenol a bis (diphenylphosphate), silicone flame retardant synergist, methyl methacrylate-styrene-silicone copolymer, and copolymer of styrene and glycidyl methacrylate.

In the preparation raw materials of the polycarbonate composition, a flame-retardant system comprises 5-12 parts by weight of bisphenol A bis (diphenyl phosphate) and 0.5-2 parts by weight of an organosilicon flame-retardant synergist; when the component amount of the single bisphenol A bis (diphenyl phosphate) or the single organosilicon flame-retardant synergist is relatively large, namely the bisphenol A bis (diphenyl phosphate) is close to 12 parts (the organosilicon flame-retardant synergist is not close to 2 parts) or the organosilicon flame-retardant synergist is close to 2 parts (the bisphenol A bis (diphenyl phosphate) is not close to 12 parts), the flame-retardant performance of the polycarbonate composition cannot reach 0.7mmV0 (as in examples 1-4). When the bisphenol A bis (diphenyl phosphate) and the organosilicon flame-retardant synergist are in a proper proportion range, although the total addition amount of the bisphenol A bis (diphenyl phosphate) and the organosilicon flame-retardant synergist is reduced to a certain extent, the flame-retardant effect on the polycarbonate composition is better, and can reach 0.7mmV0, thereby showing that the bisphenol A bis (diphenyl phosphate) and the organosilicon flame-retardant synergist have synergistic effect in the polycarbonate composition. When the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 8:2, the polycarbonate composition has the optimal flame-retardant effect, and the solvent resistance effect and the notch impact strength effect are also good.

The larger the content of acrylonitrile-butadiene-styrene copolymer and bisphenol A bis (diphenyl phosphate) in the formula, the larger the melt index of the polycarbonate composition, and the longer the solvent break resistance and the notch impact are gradually reduced, mainly because the molecular weight of the acrylonitrile-butadiene-styrene copolymer is gradually reduced, and the more bisphenol A bis (diphenyl phosphate) promotes the accelerated plasticization of the polycarbonate to weaken the molecular acting force.

The data of various properties of the polycarbonate compositions prepared in comparative examples 1 to 7 show that the polycarbonate composition prepared in example 7 has the best overall performance and the best mixture ratio of the raw materials under the comprehensive action of various factors.

Example 7 in comparison with example 8, the parallel twin-screw extruder used in example 8 had a twin-screw shape and a ratio L/D of the length L of the screw to the diameter D of the screw was 50, and the parallel twin-screw extruder used in example 7 had a single-screw shape and a ratio L/D of the length L of the screw to the diameter D of the screw was 35, and it was found by comparison that the polycarbonate composition obtained by using the parallel twin-screw extruder described in example 7 had better solvent resistance and processability.

Compared with example 7, comparative example 1 only adds one flame retardant bisphenol A bis (diphenyl phosphate) and does not add an organosilicon flame retardant synergist, and the obtained polycarbonate composition has obviously poor flame retardant performance, solvent resistance and impact strength, because the flame retardant performance of the polycarbonate composition can not reach V0 due to the single flame retardant bisphenol A bis (diphenyl phosphate) under the addition amount, and because the single flame retardant bisphenol A bis (diphenyl phosphate) has a certain plasticizing promoting effect on polycarbonate, the acting force between material molecular chains is weakened, and the macro expression is that the solvent resistance of the material is poor, the impact strength is reduced and the fluidity is increased.

Compared with example 7, in comparative example 2, only one flame retardant, namely the organosilicon flame retardant synergist, is added, and bisphenol a bis (diphenyl phosphate) is not added, so that the flame retardant performance of the obtained polycarbonate composition is deteriorated, the solvent resistance and the toughness are remarkably improved, meanwhile, the reduction of the bisphenol a bis (diphenyl phosphate) on the performance of the polycarbonate composition is laterally proved, and the solvent resistance and the toughness of the polycarbonate composition can be greatly improved by the specific siloxane group of the organosilicon flame retardant synergist.

Comparative example 3 in comparison with example 7, in comparative example 3 in which no polysiloxane-polycarbonate copolymer was added, the resulting polycarbonate composition had significantly reduced solvent resistance and impact strength, indicating that a siloxane-polycarbonate copolymer is essential for the polycarbonate composition to have improved solvent resistance and impact strength.

Comparative example 4 compared to example 7, in comparative example 4, where no polycarbonate was added, but a single polysiloxane-polycarbonate copolymer was used, the resulting polycarbonate composition, although having significantly improved solvent resistance and impact strength, had a significantly reduced melt index, which made the material difficult to process; and because polysiloxane-polycarbonate copolymers are expensive, they are difficult to apply to mass production.

Comparative example 5 compared with example 7, in comparative example 5, 6 parts of methyl methacrylate-styrene-organosilicon copolymer is added, the impact strength of the obtained polycarbonate composition is slightly improved, the difference of the material solvent resistance is not large, but the melt index is remarkably reduced, the obtained polycarbonate composition is difficult to process, and the mass production is difficult to advance.

Comparative example 6 compared with example 7, the polycarbonate composition obtained by adding 15 parts of acrylonitrile-butadiene-styrene copolymer in comparative example 6 has a significantly improved melt index, but the flame retardance, solvent resistance and impact strength of the material are obviously reduced due to the increase of the addition amount of the acrylonitrile-butadiene-styrene copolymer.

Compared with example 7, the flame retardant composition in comparative example 7 is bisphenol a bis (diphenyl phosphate) and poly spiro phosphate diamide, the flame retardant performance of the obtained flame retardant polycarbonate composition is not obviously reduced, the melt index is obviously improved, and the solvent resistance and impact strength of the material are obviously reduced, which shows that the organic silicon flame retardant synergist is obviously better than the poly spiro phosphate diamide in the aspect of improving the solvent resistance of the polycarbonate composition, so that the prepared flame retardant polycarbonate composition is more suitable for medical products.

Comparative example 8 compared to example 7, in comparative example 8, using a methyl methacrylate-styrene-butadiene copolymer as a toughening agent, the flame retardant polycarbonate composition obtained exhibited a significant decrease in flame retardant performance, solvent resistance and impact strength, in addition to an increase in melt index.

Comparative example 9 in comparison with example 7, in comparative example 9 in which a styrene maleic anhydride copolymer was used as a compatibilizer, the melt index of the resulting flame retardant polycarbonate composition was greatly reduced although the flame retardant properties, solvent resistance and impact strength were not significantly changed.

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

1. The flame-retardant polycarbonate composition is characterized by being prepared from the following raw materials in parts by weight:

wherein the total of the parts by weight of the polycarbonate resin, the polysiloxane-polycarbonate and the acrylonitrile-butadiene-styrene copolymer is 100 parts;

the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 2.5-24: 1.

2. The flame retardant polycarbonate composition of claim 1, wherein the flame retardant polycarbonate composition is prepared from the following raw materials in parts by weight:

the weight part ratio of the bisphenol A bis (diphenyl phosphate) to the organosilicon flame-retardant synergist is 3-10: 1.

3. The flame retardant polycarbonate composition of claim 2, wherein the polycarbonate composition is prepared from the following raw materials in parts by weight:

4. The flame retardant polycarbonate composition of any of claims 1-3, wherein the silicone flame retardant synergist is STR-100 and/or FAC-107.

5. The flame retardant polycarbonate composition according to any one of claims 1 to 3, wherein the mass fraction of glycidyl methacrylate in the styrene-acrylonitrile-glycidyl methacrylate copolymer is 2 to 4 wt%.

6. The flame retardant polycarbonate composition of any one of claims 1 to 3, wherein the polycarbonate resin has a melt index of 10g/10min to 12g/10 min;

and/or the melt index of the polysiloxane-polycarbonate copolymer is 3g/10 min-10 g/10min, and the siloxane content is 6 wt% -14 wt%.

7. The flame retardant polycarbonate composition of any one of claims 1 to 3, wherein the hindered phenolic antioxidant is octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate;

and/or the phosphite antioxidant is bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate;

and/or the antibacterial agent is an Ag-based carrier inorganic antibacterial agent.

8. The method of any of claims 1 to 7, comprising the steps of:

(1) mixing the dried polycarbonate resin, polysiloxane-polycarbonate copolymer, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-styrene-organosilicon copolymer and styrene-acrylonitrile-glycidyl methacrylate copolymer;

(2) mixing bisphenol A bis (diphenyl phosphate), an organosilicon flame-retardant synergist, a hindered phenol antioxidant, a phosphite antioxidant, pentaerythritol stearate, modified polytetrafluoroethylene and an antibacterial agent;

(4) and (4) adding the mixed material obtained in the step (3) into a parallel double-screw extruder through a feeder, and performing melt extrusion granulation in the parallel double-screw extruder to obtain the material.

9. The method of claim 8, wherein the melt extrusion pelletization process parameters comprise: the temperature of the first zone is 210-240 ℃, the temperature of the second zone is 230-260 ℃, the temperature of the third zone is 235-260 ℃, the temperature of the fourth zone is 220-260 ℃, the temperature of the fifth zone is 220-260 ℃, the temperature of the sixth zone is 220-260 ℃, the temperature of the seventh zone is 220-260 ℃, the temperature of the eighth zone is 220-260 ℃, the temperature of the die head is 240-275 ℃, and the rotating speed of the screw is 200-600 rpm;

and/or, the drying conditions in step (1) comprise: the temperature is 80-110 ℃, and the time is 4-8 hours;

and/or the mixing stirring speed in the step (1) is 400-600 r/m;

and/or the mixing stirring speed in the step (2) is 400-600 r/m;

and/or, the mixing in the step (3) is carried out at a stirring speed of 400-600 rpm for 8-12 min;

and/or the shape of the screw of the parallel double-screw extruder is a single 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 35-50; the screw is provided with more than 1 meshing block area and more than 1 reverse thread area.

10. The method of claim 9, wherein the melt extrusion pelletization process parameters comprise: the temperature of the first zone is 225-235 ℃, the temperature of the second zone is 235-245 ℃, the temperature of the third zone is 245-255 ℃, the temperature of the fourth zone is 245-255 ℃, the temperature of the fifth zone is 245-255 ℃, the temperature of the sixth zone is 245-255 ℃, the temperature of the seventh zone is 240-250 ℃, the temperature of the eighth zone is 240-250 ℃, the temperature of the die head is 255-265 ℃, and the rotating speed of the screw is 350-500 rpm;

and/or, the drying conditions in step (1) comprise: the temperature is 100-110 ℃, and the time is 4-6 hours;

and/or the ratio L/D of the length L of the screw to the diameter D of the screw is 35-45; and 2 meshing block areas and 1 reverse thread area are arranged on the screw rod.