CN114395239B

CN114395239B - Stable polycarbonate composition and preparation method and application thereof

Info

Publication number: CN114395239B
Application number: CN202210181431.7A
Authority: CN
Inventors: 田征宇; 刘贤文; 刘志雄; 董相茂
Original assignee: Shanghai Kingfa Science and Technology Co Ltd; Jiangsu Kingfa New Material Co Ltd
Current assignee: Shanghai Kingfa Science and Technology Co Ltd; Jiangsu Kingfa New Material Co Ltd
Priority date: 2022-02-25
Filing date: 2022-02-25
Publication date: 2023-08-11
Anticipated expiration: 2042-02-25
Also published as: CN114395239A

Abstract

The application discloses a stable polycarbonate composition, a preparation method and application thereof, and relates to the field of engineering plastics. The flame retardant comprises polycarbonate, ABS, BDP flame retardant, toughening agent, wet heat stabilizer and anti-dripping agent, wherein the wet heat stabilizer comprises carbodiimide and epoxy compatilizer, the carbodiimide comprises carbodiimide with average molecular weight of 2000-6000 monomers and polycarbodiimide with average molecular weight of 12000-20000, and the water content of the BDP flame retardant is less than or equal to 0.23%. According to the application, through adding the polycarbodiimide and the epoxy compatilizer with epoxy groups, active hydrogen in a damp-heat environment can be stabilized, hydrolysis of esters is synergistically stabilized, meanwhile, the moisture content of the BDP flame retardant is controlled, the reaction response speed of the damp-heat stabilizer is accelerated, meanwhile, the influence of excessive moisture on the damp-heat stabilization effect is avoided, the damp-heat aging stability is integrally improved, and meanwhile, excellent flame retardance and mechanical strength functions are provided.

Description

Stable polycarbonate composition and preparation method and application thereof

Technical Field

The application relates to the field of engineering plastics, in particular to a stable polycarbonate composition, a preparation method and application thereof.

Background

The halogen-free flame-retardant polycarbonate ABS alloy composition is a very general material with wide application, in order to meet the technology updating and changing requirements of the material in application, the polycarbonate composition has stable humid heat aging stability, and enough mechanical properties are ensured in the working and service process, any component added into the polycarbonate can lead to the reduction of humid heat aging stability, such as some residues in ABS, small molecules such as a toughening agent and the like, and the addition of the flame retardant can lead to the reduction of heat resistance, so that the humid heat stability is further deteriorated. The contents of the toughening agent and the flame retardant are increased to ensure that the retention rate of flame retardance and impact strength further deteriorates the phenomenon of wet heat aging, accelerates the degradation of the polycarbonate resin, and cannot provide guarantee for the service safety of mechanical properties.

The prior flame retardant and toughening technology has certain limitations, so that the application of the material is limited to a certain extent, and the problems of unstable flame retardance, reduced toughness, deteriorated appearance and the like after humid heat aging are always plagued by the development of the high performance of the material under the development trend of the industry of particularly service safety thinning.

The prior art mainly adopts PE wax with good mobility to form a barrier, thereby reducing the influence of damp and hot environment on halogen-free flame retardant PCABS, and improving the damp and heat resistance, but the PC matrix and the PE matrix are well known to have poor compatibility, so that appearance defects are easy to be caused, and the PE wax has a larger negative effect on the flame retardance and has a large influence on the fluctuation of mechanical properties. Secondly, there is also disclosed a technology for improving the wet and hot properties by a hydrophobing agent, and the problem of poor compatibility is also presented. The maleic anhydride graft modifier has limited improvement on the humid heat aging performance, but has great negative influence on the flowability.

Therefore, the prior art has various defects, and especially aims at the application fields of consumer electronics, new energy automobiles, outdoor communication and the like with ultrahigh requirements on fluidity and appearance, and the prior art is insufficient for supporting the requirement on high-performance materials.

Disclosure of Invention

The application provides a stable polycarbonate composition, a preparation method and application thereof, and provides a polycarbonate composition product with excellent flame retardance and humid heat aging stability.

In order to solve the technical problems, one of the purposes of the application is to provide a stable polycarbonate composition, which comprises the following components in parts by weight:

polycarbonate: 60-72 parts;

ABS: 5-20 parts;

BDP flame retardant: 5-16 parts;

toughening agent: 2-10 parts;

wet heat stabilizer: 0.2-2 parts;

anti-drip agent: 0.3-1 part;

the wet heat stabilizer comprises polycarbodiimide and an epoxy compatilizer, wherein the polycarbodiimide comprises monomer carbodiimide A with an average molecular weight of 2000-6000 and polycarbodiimide B with an average molecular weight of 12000-20000, and the water content of the BDP flame retardant is less than or equal to 0.23%.

The water content of the flame retardant is tested by an infrared method according to the condition of 120 ℃ for 5 min.

Through the adoption of the scheme, carbodiimide which can react with phosphate groups and accumulate double bonds and the epoxy compatilizer with epoxy groups are added, so that hydrolysis of esters can be synergistically stabilized, the influence of moisture content of components on performance is reduced, the moisture content of BDP flame retardant is controlled, the failure of stabilizing effect caused by the existence of excessive moisture when the flame retardant interacts with a wet heat stabilizer can be avoided, the humidity and heat aging resistance is integrally improved, and excellent flame retardance and mechanical strength functions are simultaneously provided.

As a preferable scheme, the wet heat stabilizer is prepared from monomer diimmonium carbide A, polycarbodiimide B and epoxy compatilizer according to the mass ratio of (1-3): (1-2): and (3) compounding the components in proportion.

As a preferable scheme, the wet heat stabilizer is prepared from monomer diimmonium carbide A, polycarbodiimide B and epoxy compatilizer according to the mass ratio of 3:1:2, compounding the components in proportion.

By adopting the scheme, the mass ratio of the monomer diimmonium carbide A, the polycarbodiimide B and the epoxy compatilizer is specifically limited, so that the synergistic effect can be improved, and the damp-heat resistance and stability can be improved.

Preferably, the average molecular weight of the monomer carbodiimide A is 2500-4500, and the average molecular weight of the polycarbodiimide B is 13500-17500.

Preferably, the epoxy compatilizer is a ternary random copolymer of styrene-acrylonitrile-glycidyl methacrylate.

Preferably, the BDP flame retardant has a water content ranging from 0.06 to 0.15 percent.

Preferably, the BDP flame retardant has a water content ranging from 0.09 to 0.12 percent.

Preferably, the toughening agent is a silicon-based toughening agent.

As a preferable scheme, the silicon toughening agent has a silica gel content of 25% -50% and a silica gel particle size of 500nm-1000nm.

Preferably, the anti-dripping agent is polytetrafluoroethylene.

Preferably, the polycarbonate has an average molecular weight of 19000-23000, a hydroxyl end group content of less than 50ppm and a BPA content of less than 20ppm.

In order to solve the above technical problems, a second object of the present application is to provide a method for preparing a stable polycarbonate composition, comprising the steps of:

(1) Weighing polycarbonate, ABS, a flame retardant, a toughening agent, a wet heat stabilizer and an anti-dripping agent according to the proportion, and stirring and blending in a high-speed mixer to obtain a premix;

(2) And extruding and granulating the premix to obtain the polycarbonate composition.

In order to solve the technical problems, the application provides a stable polycarbonate composition applied to the fields of security protection, new energy and communication.

Compared with the prior art, the embodiment of the application has the following beneficial effects:

1. according to the application, through adding the polycarbodiimide which can react with the phosphate group and accumulate double bonds and the epoxy compatilizer with the epoxy group, the wet heat stabilizer with specific average molecular weight can stabilize active hydrogen in a wet heat environment, comprises water in the wet heat environment and polar end groups of PC resin, synergistically stabilizes hydrolysis of esters, integrally improves the humidity and heat aging resistance, and simultaneously endows excellent flame retardance and mechanical strength functions.

2. Meanwhile, the moisture content of the BDP flame retardant is controlled, the reaction response speed of the wet heat stabilizer can be accelerated due to the existence of certain moisture content, and meanwhile, the failure of the stabilizing effect caused by the existence of excessive moisture when the flame retardant interacts with the wet heat stabilizer can be avoided.

Detailed Description

The technical solutions of the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

TABLE 1 sources and types of raw materials used in examples and comparative examples of the present application

Example 1

A stable polycarbonate composition comprising 70kg of polycarbonate, 10kg of ABS, 12kg of BDP flame retardant, 5kg of toughening agent, 0.5kg of moisture and heat stabilizer, 0.8kg of anti-drip agent; weighing polycarbonate, ABS, flame retardant, toughening agent, wet heat stabilizer and anti-dripping agent according to the proportion, stirring and blending in a high-speed mixer to obtain premix, and then performing double-screw extrusion and granulation procedures to obtain the polycarbonate alloy composition.

Wherein the polycarbonate is prepared by a phosgene method, the average molecular weight of the polycarbonate is 23000, the hydroxyl end content is 47ppm, the BPA content is 12ppm, and the brand of Mitsubishi engineering in Shanghai is specifically selected as S-2000F; ABS is polymerized by a bulk method, the glue content is 15%, and the brand of Shanghai high bridge is 275; the BDP flame retardant is prepared by mixing bisphenol A bis (diphenyl phosphate) with the water content of less than 0.01 percent and the water content of 0.23 percent to obtain the BDP flame retardant with the water content of 0.09 percent; the toughening agent is a silicon toughening agent, the silica gel content is 30%, the silica gel particle size is 800nm, and the brand of Mitsubishi Li yang is specifically selected as S-2130; the anti-dripping agent is polytetrafluoroethylene; the wet heat stabilizer is prepared from monomer carbodiimide with average molecular weight of 3000 and polycarbodiimide with average molecular weight of 12000 according to mass ratio of 3:1:2, wherein the epoxy compatilizer is a ternary random copolymer of styrene-acrylonitrile-glycidyl methacrylate, and SAG-001 is specifically selected.

Example two

A stable polycarbonate composition comprising 60kg of polycarbonate, 15kg of ABS, 5kg of BDP flame retardant, 10kg of toughening agent, 0.2kg of moisture and heat stabilizer, 1kg of anti-drip agent; weighing polycarbonate, ABS, flame retardant, toughening agent, wet heat stabilizer and anti-dripping agent according to the proportion, stirring and blending in a high-speed mixer to obtain premix, and then performing double-screw extrusion and granulation procedures to obtain the polycarbonate alloy composition.

Wherein the polycarbonate is prepared by a phosgene method, the average molecular weight of the polycarbonate is 23000, the hydroxyl end content is 47ppm, the BPA content is 12ppm, and the brand of Mitsubishi engineering in Shanghai is specifically selected as S-2000F; ABS is polymerized by a bulk method, the glue content is 15%, and the brand of Shanghai high bridge is 275; the BDP flame retardant is prepared by mixing bisphenol A bis (diphenyl phosphate) with the water content of less than 0.01 percent and the water content of 0.23 percent to obtain the BDP flame retardant with the water content of 0.09 percent; the toughening agent is a silicon toughening agent, the silica gel content is 30%, the silica gel particle size is 800nm, and the brand of Mitsubishi Li yang is specifically selected as S-2130; the anti-dripping agent is polytetrafluoroethylene; the wet heat stabilizer is prepared from monomer carbodiimide with average molecular weight of 3000 and polycarbodiimide with average molecular weight of 12000 according to mass ratio of 3:1:2, wherein the epoxy compatilizer is a ternary random copolymer of styrene-acrylonitrile-glycidyl methacrylate, and SAG-002 is specifically selected.

Example III

A stable polycarbonate composition comprising 72kg of polycarbonate, 20kg of ABS, 16kg of BDP flame retardant, 2kg of toughener, 2kg of moisture and heat stabilizer, 0.3kg of anti-drip agent; weighing polycarbonate, ABS, flame retardant, toughening agent, wet heat stabilizer and anti-dripping agent according to the proportion, stirring and blending in a high-speed mixer to obtain premix, and then performing double-screw extrusion and granulation procedures to obtain the polycarbonate alloy composition.

Example IV

The stabilized polycarbonate composition was prepared in the same manner as in example one, except that the moisture and heat stabilizer was prepared from a monomer carbodiimide having an average molecular weight of 3000 and a polycarbodiimide having an average molecular weight of 12000, and an epoxy-based compatibilizer in a mass ratio of 1:1:1, and mixing the materials in proportion.

Example five

The stabilized polycarbonate composition was prepared in the same manner as in example one, except that the moisture and heat stabilizer was prepared from a monomer carbodiimide having an average molecular weight of 3000 and a polycarbodiimide having an average molecular weight of 12000, and an epoxy-based compatibilizer in a mass ratio of 1:2:3, and mixing the materials in proportion.

Example six

A stable polycarbonate composition was prepared using the same reagents and process parameters as in example one, except that BDP flame retardant was mixed with bisphenol A bis (diphenyl phosphate) having a water content of less than 0.01% and a water content of 0.23% to give a flame retardant having a water content of 0.12% (the water content was measured by infrared method at 120 degrees for 5 minutes).

Example seven

A stable polycarbonate composition was prepared in the same manner as in example I except that BDP flame retardant was prepared by mixing bisphenol A bis (diphenyl phosphate) having a water content of less than 0.01% and a water content of 0.23% to give a flame retardant having a water content of 0.09% (the water content was measured by infrared method under the condition of 120 degrees for 5 minutes). Example eight

The stabilized polycarbonate composition was prepared in the same manner as in example one, except that the moisture and heat stabilizer was prepared from a monomer carbodiimide having an average molecular weight of 2500 and a polycarbodiimide having an average molecular weight of 17500, and an epoxy-based compatibilizer in a mass ratio of 3:1:2, and mixing the materials in proportion.

Example nine

The stabilized polycarbonate composition was prepared in the same manner as in example one, except that the moisture and heat stabilizer consisted of a monomeric carbodiimide having an average molecular weight of 4500 and a polycarbodiimide having an average molecular weight of 13500, and an epoxy-based compatibilizer in a mass ratio of 3:1:2, and mixing the materials in proportion.

Comparative example one

A stable polycarbonate composition was prepared in the same manner as in example one, except that the wet heat stabilizer was replaced with an aziridine.

Comparative example two

The stabilized polycarbonate composition, the reagents and process parameters used in each step are the same as in example one, except that the wet heat stabilizer is replaced with melamine.

Comparative example three

The stabilized polycarbonate compositions were prepared in the same manner as in example one, except that the wet heat stabilizer was replaced with isocyanate.

Comparative example four

A stable polycarbonate composition was prepared using the same reagents and process parameters as in example one, except that the BDP flame retardant was bisphenol A bis (diphenyl phosphate) having a water content of 1.2%.

Comparative example five

The stable polycarbonate composition, the reagents and process parameters used in each step are the same as those in the first embodiment, except that the moisture-heat stabilizer is prepared from monomer carbodiimide with molecular weight of 3000 and epoxy compatilizer according to the mass ratio of 2:1, and mixing the materials in proportion.

Comparative example six

The stabilized polycarbonate composition was prepared in the same manner as in example one, except that the moisture and heat stabilizer was prepared from a polycarbodiimide having a molecular weight of 12000 and an epoxy compatibilizer in a mass ratio of 2:1, and mixing the materials in proportion.

Comparative example seven

A stable polycarbonate composition was prepared in the same manner as in example I except that the polycarbodiimide having an average molecular weight of 12000 was replaced with a polycarbodiimide having an average molecular weight of 10000.

Comparative example eight

A stable polycarbonate composition was prepared in the same manner as in example one, except that the monomer carbodiimide having an average molecular weight of 3000 was replaced with a carbodiimide having an average molecular weight of 1000.

Comparative example nine

The stabilized polycarbonate composition, the reagents and process parameters used in each step are the same as in example one, except that the wet heat stabilizer is an epoxy-based compatibilizer.

Performance test

1) Flame retardant rating: the flammability test was performed according to the protocol of "flammability test of plastic materials, UL94-2013", to derive flame retardant rating based on burn rate, extinguishing time, ability to resist low drop, and whether low drop is burning; sample for testing: 125mm length 13mm width and thickness 1.0mm, the flame retardant rating of the material can be classified as (UL 94-HB) according to UL94 protocol: v0, V1, V2, 5VA and/or 5VB; meanwhile, the flame retardant rating of the sample was measured under the same conditions after the sample was subjected to a humid heat aging treatment of 85% at a set temperature of 85℃in a constant temperature and humidity cabinet for 500 hours, and the test results are shown in Table 2.

2) Impact strength retention: IZOD notched impact strength of 3.0mm was tested according to ASTM D256-2010; the notch type is an injection molding notch, and after the samples are subjected to the humid heat aging treatment of 500 hours, 1000 hours and 2000 hours with the humidity of 85% at the temperature of 85 ℃ in a constant temperature and humidity box, the samples are placed in the environment with the humidity of 50% at the room temperature of 25 ℃ for more than 48 hours, then tested and recorded, and the performance retention rate before and after aging is compared to judge whether the humid heat performance is good or not, wherein the higher the performance retention rate is, the better the humid heat stability is, and the detection results are shown in table 2.

3) Color stability: the sample is measured, subjected to wet heat aging treatment with the temperature of 85 ℃ and the humidity of 85% in a constant temperature and humidity box, the Lab value is subjected to numerical difference before and after the wet heat aging treatment for 500 hours by a color difference instrument, 3 points are tested at different positions on a color plate with the thickness of 2.0mm by a calculation formula of a color difference delta E, the corresponding test value is recorded, the final result is obtained by calculating the average value, the larger the color difference delta E is, the worse the color stability is, the lower the color difference delta E is, the better the color stability is, and the detection result is shown in a table 2.

TABLE 2 Performance test results for examples 1-9 and comparative examples 1-9

As is clear from the results of performance tests of examples 1 and comparative examples 5 to 6 and 9 in Table 2, by adding carbodiimide which can react with phosphate groups and accumulate double bonds and an epoxy-based compatibilizer having an epoxy group, hydrolysis of esters can be synergistically stabilized, polycarbodiimide having a certain molecular weight can stabilize active hydrogen in a humid and hot environment, and a small amount of moisture contained in BDP flame retardance can also promote the reaction rate of a humid and heat stabilizer, thereby improving the efficient effect of resistance to humid and heat aging.

As is clear from the results of the performance tests of example 1 and comparative examples 7 to 8 in Table 2, by specifically limiting the molecular weights of the monomeric and polycarbodiimides, the reaction is prevented from being too severe and unstable due to too small molecular weight of the monomeric carbodiimide, and the reaction rate is prevented from being too low due to too high melting point of the polycarbodiimide, thereby affecting the resistance to humid and heat aging.

As can be seen from the performance test results of example 1 and comparative example 4 in Table 2, the preferred BDP water content of the present application is less than or equal to 0.23%, which can better maintain the water content of the polycarbonate composition, and avoid the influence of excessive water on the interaction stability of the flame retardant and the moisture and heat stabilizer, and on the moisture and heat stability resistance.

The finally obtained polycarbonate composition has the humidity and heat aging resistance and excellent flame retardance and mechanical strength functions, can be applied to the fields of security protection, new energy, communication and the like, and is particularly used for coffee machines, new energy batteries, monitoring cameras and the like.

The foregoing embodiments have been provided for the purpose of illustrating the general principles of the present application, and are not to be construed as limiting the scope of the application. It should be noted that any modifications, equivalent substitutions, improvements, etc. made by those skilled in the art without departing from the spirit and principles of the present application are intended to be included in the scope of the present application.

Claims

1. A stable polycarbonate composition characterized by comprising the following components in parts by weight:

polycarbonate: 60-72 parts;

ABS: 5-20 parts;

BDP flame retardant: 5-16 parts;

toughening agent: 2-10 parts;

wet heat stabilizer: 0.2-2 parts;

anti-drip agent: 0.3-1 part;

the wet heat stabilizer comprises carbodiimide and an epoxy compatilizer, wherein the carbodiimide comprises monomer carbodiimide A with an average molecular weight of 2000-6000 and polycarbodiimide B with an average molecular weight of 12000-20000, and the water content of the BDP flame retardant is less than or equal to 0.23%; the wet heat stabilizer is prepared from monomer carbodiimide A, polycarbodiimide B and epoxy compatilizer according to the mass ratio of (1-3): (1-2): compounding the components in the proportion of (1-3); the epoxy compatilizer is a ternary random copolymer of styrene-acrylonitrile-glycidyl methacrylate.

2. A stable polycarbonate composition as defined in claim 1, wherein the monomeric carbodiimide a has an average molecular weight of 2500 to 4500 and the polymeric carbodiimide B has an average molecular weight of 13500 to 17500.

3. A stabilized polycarbonate composition as defined in claim 1 wherein said BDP flame retardant has a moisture content in the range of 0.06 to 0.15%.

4. A stabilized polycarbonate composition as defined in claim 3 wherein said BDP flame retardant has a moisture content in the range of 0.09 to 0.12%.

5. A stabilized polycarbonate composition as defined in claim 1 wherein the toughening agent is a silicon based toughening agent and the anti-drip agent is polytetrafluoroethylene.

6. A stable polycarbonate composition as defined in claim 1, wherein the silicon based toughening agent has a silica gel content of 25% to 50% and a silica gel particle size of 500nm to 1000nm.

7. A process for the preparation of a stabilized polycarbonate composition, characterized in that it comprises the steps of:

8. Use of the stabilized polycarbonate composition of any of claims 1-6 in security, new energy and communications applications.