CN115368723A - Formula and preparation method of a high-impact, low-temperature, flame-retardant PC/PBT alloy material - Google Patents

Abstract

The invention provides a formula and preparation method of a high-impact, low-temperature, and flame-retardant PC/PBT alloy material. The alloy material is composed of the following raw materials in parts by weight: 40-70 parts of PC, 30-60 parts of PBT, and 5-15 parts of flame retardant , 0-5 parts of synergistic flame retardant, 0.2-5 parts of transesterification inhibitor, 2-10 parts of toughening compatibilizer, 2-10 parts of low-temperature toughening agent, and 0.01-0.3 parts of antioxidant. Dry PC and PBT in a drying oven; mix in a high-speed mixer at a speed of 100-500r/min for 2-5 minutes to obtain a uniform mixture; melt and extrude in a twin-screw granulator, and the strips are cooled and pelletized through a water tank A PC/PBT alloy material with high impact resistance, low temperature resistance and flame retardancy is obtained. The high-impact, low-temperature and flame-retardant PC/PBT alloy material of the present invention has the advantages of excellent flame retardancy, low-temperature resistance, high impact resistance, and good processability, and the process conditions involved are easy to control, and are suitable for industrial production.

Description

Formula and preparation method of a high-impact, low-temperature, flame-retardant PC/PBT alloy material

technical field

The invention provides a formula and a preparation method of a PC/PBT alloy material with high impact resistance and low temperature resistance, and belongs to the technical field of polymer materials.

Background technique

PC/PBT alloy material has the advantages of both PC and PBT. First, relative to the impact strength of modified base resin, PC/PBT alloy usually reduces the impact strength compared with PC, but the impact strength of the alloy can be improved by technical means. It remains the same as before modification; secondly, under low temperature environment, alloy plastics usually become brittle, and the impact strength will decrease. Through technical means, the alloy also has better impact strength under low temperature conditions. Low temperature resistance is also a property of specific plastics. Not all plastics have low temperature resistance, but specifically for PC/PBT alloys, it usually refers to the range of -20 to -50 °C. It not only has PC's excellent impact resistance, heat resistance, high strength and elastic coefficient, and low molding shrinkage; at the same time, it has excellent chemical resistance of PBT, no stress cracking, and is widely used in automobiles, electronics and other fields. . The PC/PBT alloy material itself does not have flame retardancy, and with the increase of PBT content, the flame retardancy of the alloy material will decrease, and in the fields of electronics, home appliances, etc., the material is required to have a certain flame retardancy, so it is necessary It is flame retardant modified. Like other plastics, the toughness of PC/PBT plastic alloys will be greatly affected by temperature, generally manifested as low temperature brittleness, so it can be modified for low temperature resistance and impact resistance, and can still maintain high toughness and strength under low temperature conditions , to broaden the application fields of PC/PBT alloy materials.

Ma Mei et al. (Ma Mei, Lei Zubi. Research on Low Temperature Impact Modification of PBT/PC[J]. Synthetic Materials Aging and Application. 2019,48(06):19-20.) studied MBS and ACR shells Nuclear impact modifiers used alone or in combination, found that the two kinds of tougheners modified PBT/PC together, the material not only has excellent toughness at room temperature, but also can reach 50kJ/ More than m ² , no research on flame retardancy was conducted; Chen Wei et al. 46(04):44-46; Chen Wei, Chen Rui, Feng Jian, et al. Research on the Influence of Resin Viscosity and Compounding Ratio on the Properties of PBT/PC Alloy[J].Guangdong Chemical Industry.2019,46(03):45- 47.) In the flame retardant system, the influence of resin compounding ratio, different tougheners and dosage on the mechanical properties of alloy materials was studied. The notched impact strength at -30°C was about 200J/m, but the flame retardant level was not specified; Kong Wei (Kong Wei. Research on the preparation and properties of low temperature flame retardant PC/PET alloy [J]. Plastic Industry. 2021,49(08):145-148.) research shows that the increase of the amount of toughening agent will lead to Thermal, mechanical strength and flame retardant properties are reduced. In summary, the toughening agent with glycidyl methacrylate (GMA) functional group can react with PC and PBT respectively due to its special molecular structure, so as to achieve the effect of toughening and compatibilizing, but excessive use will cause As a result, the heat resistance and flame retardancy of the alloy are significantly reduced, and the low temperature resistance is poor, increasing the proportion of PC and increasing the cost.

Contents of the invention

Aiming at the deficiencies of the prior art, the present invention adjusts the ratio of PC and PBT resin, and on the basis of using toughening agent with GMA functional group, adds a low-temperature resistant silicon-containing toughening agent, which not only enhances the fusion between PC and PBT interface, Moreover, the low temperature resistance of the alloy is improved; in addition, the silicon-containing toughening agent can improve the flame retardancy of the alloy; a flame retardant system with better compatibility with the PC/PBT alloy system and less impact on its mechanical properties is selected, Finally, a PC/PBT alloy material with excellent properties such as high impact resistance, low temperature resistance and flame retardancy is obtained.

The invention provides a PC/PBT alloy material with high impact resistance and low temperature resistance and a preparation method thereof. Toughening agent, improve the low temperature resistance of PC/PBT alloy and reduce the difficulty of flame retardancy of alloy materials; thirdly, use high-efficiency flame retardant to improve the flame retardancy of PC/PBT.

The present invention proposes the scheme for solving the existing problem as follows:

A formulation of a high-impact, low-temperature, and flame-retardant PC/PBT alloy material, consisting of the following components in parts by weight:

The melt index of the PC is 5-20 g/min; the intrinsic viscosity of the PBT is 0.8-1.3 dL/g (25° C.).

The flame retardant is brominated flame retardant; synergistic flame retardant contains antimony flame retardant.

The brominated flame retardant is phenoxy tetrabromobisphenol A carbonate oligomer or tris(tribromophenoxy) triazine; the synergistic flame retardant is antimony trioxide or modified trioxide Antimony.

The transesterification inhibitor is ESC-PGP.

The toughening compatibilizer is ethylene-methyl acrylate-glycidyl methacrylate or ethylene-butyl acrylate-glycidyl methacrylate.

The low-temperature toughening agent is a product of cross-linked acrylate and silicone copolymer as the core, and grafted polymethyl methacrylate as the shell, specifically S-2001, S-2030 and other silicon-containing toughening agents . .

The described antioxidant is tetrakis [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester and phosphorous acid tris (2,4-di-tert-butylphenyl) A mixture of esters, the mass ratio of the two is 1:1.

10. A preparation of a high-impact, low-temperature and flame-retardant PC/PBT alloy material, characterized in that it comprises the following steps:

(1) Pre-drying of raw materials: drying PC and PBT in a drying oven; drying conditions: drying at 120°C for 4 to 6 hours;

(2) take each component according to the PC/PBT alloy material formula of claim 1, mix 2～5min with the rotating speed of 100～500r/min in high mixer, the homogeneous mixture that obtains;

(3) The homogeneous mixture obtained in step (2) is melted and extruded in a twin-screw granulator at 240-280°C, and the strip is cooled and pelletized in a water tank to obtain a high-impact, low-temperature, flame-retardant PC/PBT alloy material.

The adjustment of the resin ratio in the present invention reduces the PC ratio and reduces the cost; it proposes the synergistic effect of the toughening compatibilizer and the low-temperature toughening agent, which has an incomparable effect compared with using a single toughening agent. The current formula mostly uses GMA toughening agent or traditional ABS toughening agent, which is limited in improving impact performance and flame retardancy; Improve the flame retardant performance of the material.

The present invention uses bromine-based flame retardants and antimony-based synergistic flame retardants, which can greatly improve the flame-retardant performance of PC/PBT alloy materials, and use the toughening agent with GMA (glycidyl methacrylate) functional structure It can be used in combination with low-temperature toughening agent to greatly improve the low-temperature and high-impact performance of PC/PBT alloy materials.

Concrete beneficial effect of the present invention is:

1. The PBT content in the PC/PBT alloy material prepared by the present invention is relatively high, which improves the rigidity of the PC/PBT alloy material and is not affected by temperature.

2. The PC/PBT alloy material prepared by the present invention has an impact strength of 900J/m at normal temperature (23°C), and 200J/m at low temperature (-30°C) while the flame retardancy level reaches 0.6mmV0.

3. The flame retardancy of the PC/PBT alloy material prepared by the present invention reaches V0 level (UL94 0.6mm), which improves the flame retardancy of the PC/PBT alloy material.

Detailed ways

The present invention will be described in further detail below in conjunction with specific embodiments.

Preferred materials are as follows:

PC: PC-141R, SABIC Corporation.

PBT: PBT-1100A, Taiwan Changchun Chemical Company.

Brominated flame retardants: BC-58, Great Lakes, USA.

Synergistic flame retardant: antimony trioxide (purity 99.5%), Yiyang Tianxing Antimony Industry Co., Ltd.

Transesterification inhibitor: ESC-PGP, Nanjing Fuju Chemical Co., Ltd.

Toughening compatibilizer: ethylene-methyl acrylate-glycidyl methacrylate, Arkema, France.

Low temperature toughening agent: S2030, Mitsubishi Corporation of Japan.

Antioxidant: Irganox1010, Irganox168, BASF

The formula is shown in Table 1.

Table 1 composition formula

name Example 1 Example 2 Example 3 Example 4 Example 5 PC 70 60 50 50 40 PBT 30 40 50 50 60 BC-58 5 7 10 12 15 Antimony trioxide 0 1 3 3 5 toughening compatibilizer 2 3 5 10 10 Low temperature toughener 2 10 7 5 10 antioxidant 0.01 0.1 0.2 0.3 0.1

The above formula is just an example, and other substances in the formula cited in the summary of the invention can achieve the same effect, so details will not be repeated here.

Preparation:

After mixing the dried PC and PBT and other components according to the formula in Table 1, they are added to the main barrel of the twin-screw extruder for melting and extrusion; the processing technology of the twin-screw extruder is as follows: the twin-screw extruder The processing temperature is 240-280°C. The extruder includes seven temperature zones, one of which is 240°C, the second section is 250°C, the third section is 255°C, the fourth section is 255°C, the fifth section is 255°C, the sixth section is 250°C, and the seventh section is 250°C. 245°C, screw speed 500r/min. The product of the present invention is obtained after the final granulation, drying and other processes.

Dry the above product in a drying oven at 100°C for 4 hours, and inject it into an ASTM standard sample with a plastic injection molding machine at an injection temperature of 255°C; place the injected sample at 50% relative humidity and 23°C for 24 hours After testing the performance, the low-temperature notched impact strength was placed at -30°C for 3 hours to test the performance.

Product performance testing methods are as follows:

Tensile strength test: according to ASTM D638 standard.

Bending strength test: according to ASTM D790 standard.

Notched impact strength test: according to ASTM D256 standard.

Vertical burning level test: according to UL94 standard.

The performance test results are shown in Table 2.

Table 2 performance test results

The high-impact, low-temperature and flame-retardant PC/PBT alloy material prepared by the present invention has excellent flame-retardant properties, processing properties and mechanical properties. Compared with the background technology, the impact performance and flame-retardant properties are improved at the same time; it can be widely used in It is suitable for fields with flame retardant requirements such as automobiles and electronic appliances, and is easy to industrialized production, so it has great market prospects.

The above-mentioned embodiments are only descriptions of preferred implementations of the present invention, and are not intended to limit the scope of the present invention. Variations and improvements should fall within the scope of protection defined by the claims of the present invention.

Claims (9)

1. A formulation of high-impact, low-temperature and flame-retardant PC/PBT alloy material, characterized in that it consists of the following components in parts by weight:

2. The formula of high-impact, low-temperature and flame-retardant PC/PBT alloy material as claimed in claim 1, characterized in that, the melt index of PC is 5-20g/min; the intrinsic viscosity of PBT is 0.8-1.3dL/g (25°C ). 3. The formula of high-impact, low-temperature and flame-retardant PC/PBT alloy material as claimed in claim 1, wherein the flame retardant is a brominated flame retardant; the synergistic flame retardant contains antimony flame retardant. 4. the formula of high-impact low-temperature flame-retardant PC/PBT alloy material as claimed in claim 1, is characterized in that, brominated flame retardant is phenoxytetrabromobisphenol A carbonate oligomer or three (three bromophenoxy) triazine; the synergistic flame retardant is antimony trioxide or modified antimony trioxide. 5. The formula of high-impact and low-temperature flame-retardant PC/PBT alloy material as claimed in claim 1, wherein the transesterification inhibitor is ESC-PGP. 6. The formula of high-impact, low-temperature and flame-retardant PC/PBT alloy material as claimed in claim 1, wherein the toughening compatibilizer is ethylene-methyl acrylate-glycidyl methacrylate or ethylene-butyl acrylate Esters - Glycidyl Methacrylate. 7. The formula of high-impact, low-temperature and flame-retardant PC/PBT alloy material according to claim 1, wherein the low-temperature toughening agent is S-2001, S-2051, S-2030 or S-2050. 8. The formula of high-impact and low-temperature flame-retardant PC/PBT alloy material as claimed in claim 1, wherein the antioxidant is tetrakis[β-(3,5-di-tert-butyl-4- A mixture of hydroxyphenyl) propionate] pentaerythritol ester and tris (2,4-di-tert-butylphenyl) phosphite, the mass ratio of the two is 1:1. 9. A preparation of a high-impact, low-temperature and flame-retardant PC/PBT alloy material, characterized in that it comprises the following steps: (1) Pre-drying of raw materials: drying PC and PBT in a drying oven; drying conditions: drying at 120°C for 4 to 6 hours; (2) take each component according to the PC/PBT alloy material formula of claim 1, mix 2～5min with the rotating speed of 100～500r/min in high mixer, the homogeneous mixture that obtains; (3) The homogeneous mixture obtained in step (2) is melted and extruded in a twin-screw granulator at 240-280°C, and the strip is cooled and pelletized in a water tank to obtain a high-impact, low-temperature, flame-retardant PC/PBT alloy material.