PBT / PC (polybutylene terephthalate / polycarbonate) composition as well as preparation method and application thereof

Abstract

The invention relates to a PBT / PC (polybutylene terephthalate / polycarbonate) composition as well as a preparation method and application thereof. The PBT / PC composition is prepared from the following components in parts by weight: 30 to 50 parts of PBT resin, 15 to 20 parts of PC resin, 15 to 35 parts of brominated PC, 2 to 9 parts of other brominated flame retardants, 0.1 to 1 part of antimony flame retardants, 3 to 7 parts of phosphate flame retardants and 8 to 15 parts of silicon flexibilizers. According to the invention, PBT and PC are taken as base materials, brominated PC, other brominated flame retardants, antimony flame retardants and phosphate flame retardants are taken as compound flame retardants, and a silicon flexibilizer is taken as a special flexibilizer, so that the toughness, fluidity, flame retardancy and electrical properties of the material are synergistically improved, and the requirements of the fields of connectors, wiring terminals and the like on material properties can be well met; the problem that the electrical property of a nylon material is reduced due to water absorption is solved, and the material has high practical application value.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer material processing, and relates to a PBT / PC composition, a preparation method thereof, and an application thereof. Background Art

[0002] In the fields of connectors, terminal blocks, etc., nylon materials have been widely used and have developed well due to their good toughness, good fluidity, and good mechanical properties. However, as people's requirements for the electrical properties of materials become higher and higher, the problem of the decline in electrical properties after nylon absorbs moisture gradually appears.

[0003] CN105440597A discloses a high glow wire flame retardant reinforced PBT composite material and a preparation method thereof. The high glow wire flame retardant reinforced PBT composite material comprises the following components: polybutylene terephthalate 50-60 wt%, a composite flame retardant 20 wt%, glass fiber 20 wt%, and a graft compatibilizer 0-10 wt%. However, this system is a halogen-free flame retardant system and has poor mechanical properties.

[0004] CN111808405A discloses a polyester material with a high glow wire ignition temperature, comprising the following components in parts by weight: polyester resin 25-40 parts, non-alkali glass fiber 25-40 parts, bromine-based flame retardant 18-30 parts, nitrogen-containing smoke suppressant 3-8 parts, and phosphate flame retardant synergist 2-10 parts; the non-alkali glass fiber is non-alkali glass fiber treated with a coupling agent. However, 25-40 parts of glass fiber are added to this system, and the deflection is low.

[0005] CN109486123A discloses an impact-resistant high glow wire ignition temperature PBT material, which is composed of the following mass percentages: PBT resin 50-65%, toughening agent 5-15%, flame retardant 18-30%, antioxidant 0.1-0.6%, lubricant 0.3-0.8%, anti-dripping agent 0.1-0.5%, and calcium carbonate 1-3%. However, its ISO notched impact strength is low, only 7-8 kg / cm 2 .

[0006] Therefore, it is necessary to develop a PBT / PC composition with high flame retardancy and high toughness to meet the requirements of electronic components for materials. Summary of the Invention

[0007] To solve the above technical problems, the present invention provides a PBT / PC composition, its preparation method and application. The present invention uses polybutylene terephthalate (PBT) and polycarbonate (PC) as the base materials, brominated PC, other brominated flame retardants, antimony-based flame retardants and phosphate flame retardants as the compound flame retardants, and a silicon-based toughening agent as a special toughening agent, synergistically improving the toughness, fluidity, flame retardancy and electrical properties of the material, which can well meet the requirements of the material properties in the fields such as connectors and terminal blocks, solve the problem that the electrical properties of nylon materials decrease due to water absorption, and has high practical application value.

[0008] To achieve this purpose, the present invention adopts the following technical solutions:

[0009] In the first aspect, the present invention provides a PBT / PC composition, and the PBT / PC composition comprises the following components by weight:

[0010]

[0011] In the present invention, the PBT resin can be 30 parts, 34 parts, 38 parts, 42 parts, 46 parts, 50 parts, etc.; the PC resin can be 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, etc.; the brominated PC can be 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, etc.; the other brominated flame retardants can be 2 parts, 4 parts, 6 parts, 8 parts, 9 parts, etc.; the antimony-based flame retardants can be 0.1 part, 0.2 part, 0.4 part, 0.6 part, 0.8 part, 1 part, etc.; the phosphate flame retardants can be 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, etc.; the silicon-based toughening agent can be 8 parts, 10 parts, 12 parts, 14 parts, 15 parts, etc.

[0012] The present invention uses PBT and PC as the base materials, avoiding the addition of glass fibers, so it has very good toughness and fluidity; uses brominated PC, other brominated flame retardants, antimony-based flame retardants and phosphate flame retardants as the compound flame retardants, and the compounding of four different types of flame retardants has a synergistic effect, jointly improving the flame retardancy of the product and making it have a higher glow wire ignition temperature; uses a silicon-based toughening agent as a special toughening agent, which not only improves the notched Izod impact strength and fluidity of the material, but also the silicon-containing toughening agent can cooperate with the above four compound flame retardants to synergistically improve the flame retardancy.

[0013] In the present invention, the compound flame retardant uses brominated PC as the main flame retardant, which not only has a flame retardant effect, but also has little influence on the properties of the material. At the same time, other flame retardants are compounded to jointly improve the flame retardancy of the product on the basis of ensuring the product performance.

[0014] The PBT / PC composition provided by the present invention is combined with specific types and dosages, and each component can play a synergistic role. The resulting product has good toughness, fluidity, flame retardancy and electrical properties, can well meet the material property requirements in the fields of connectors, terminal blocks, etc., solve the problem that the electrical properties of nylon materials decrease due to water absorption, and has high practical application value.

[0015] Preferably, the mass percentage content of PBT resin in the PBT / PC composition is 30-50% (for example, it can be 30%, 34%, 38%, 42%, 46%, 50%, etc.).

[0016] Preferably, the mass percentage content of PC resin in the PBT / PC composition is 12-25% (for example, it can be 12%, 15%, 16%, 17%, 18%, 19%, 20%, 25%, etc.).

[0017] Preferably, the mass percentage content of brominated PC in the PBT / PC composition is 15-35% (for example, it can be 15%, 20%, 25%, 30%, 35%, etc.).

[0018] Preferably, the mass percentage content of other brominated flame retardants in the PBT / PC composition is 1-10% (for example, it can be 1%, 2%, 4%, 6%, 8%, 9%, 10%, etc.).

[0019] Preferably, the mass percentage content of antimony-based flame retardants in the PBT / PC composition is 0.05-1% (for example, it can be 0.05%, 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1%, etc.).

[0020] Preferably, the mass percentage content of phosphate ester flame retardants in the PBT / PC composition is 2-8% (for example, it can be 2%, 3%, 4%, 5%, 6%, 7%, 8%, etc.).

[0021] Preferably, the mass percentage content of silicone-based toughening agents in the PBT / PC composition is 8-15% (for example, it can be 8%, 10%, 12%, 14%, 15%, etc.).

[0022] Preferably, the intrinsic viscosity of the PBT resin is 0.73-1.3 dl / g, for example, it can be 0.73 dl / g, 0.8 dl / g, 0.9 dl / g, 1 dl / g, 1.1 dl / g, 1.2 dl / g, 1.3 dl / g, etc. The intrinsic viscosity can be measured by method A in the standard GB / T14190-2008. The specific method is: measure the efflux time of the solvent at 25°C and the PBT solution with a concentration of 0.005 g / mL, and calculate its intrinsic viscosity according to the measured efflux time and the solution concentration of the sample.

[0023] Preferably, the melt index of the PC resin under the conditions of 300 °C and 1.2 kg is 2-25 g / 10 min. For example, it can be 2 g / 10 min, 5 g / 10 min, 10 g / 10 min, 15 g / 10 min, 20 g / 10 min, 25 g / 10 min, etc. The melt index is obtained by testing according to ASTM D1238 standard.

[0024] Preferably, the brominated PC is a random copolymer of phosgene, tetrabromobisphenol A and bisphenol A.

[0025] Preferably, the structural formula of the brominated PC is as follows:

[0026]

[0027] Wherein, X:Y = 1:2 - 1:5. For example, it can be 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, etc. The bromine content (by mass) in the corresponding brominated PC is 15-30%. For example, it can be 15%, 18%, 20%, 22%, 25%, 28%, 30%, etc.

[0028] In the present invention, the values of X and Y should satisfy that the bromine element content (mass ratio) in the brominated PC ≥ 15%. If the bromine content is too low, the flame retardant effect is not good.

[0029] Preferably, the other bromine-based flame retardants include any one or a combination of at least two of brominated epoxy, brominated polystyrene, decabromodiphenylethane, brominated polycarbonate, pentabromobenzyl acrylate or brominated imide;

[0030] Preferably, the antimony-based flame retardants include any one or a combination of at least two of antimony white, sodium antimonate or antimony chloride.

[0031] Preferably, the phosphate ester flame retardants include any one or a combination of at least two of resorcinol bis[bis(2,6-dimethylphenyl) phosphate], hydroquinone bis(diphenyl phosphate) or triphenyl phosphate.

[0032] The silicone-based toughening agent includes a copolymer of (meth)acrylate monomer and siloxane monomer.

[0033] Preferably, the acrylate monomers include any one or a combination of at least two of methyl methacrylate, ethyl acrylate or butyl acrylate.

[0034] Preferably, the siloxane monomers include any one or a combination of at least two of dimethyl siloxane, methyl siloxane or siloxane.

[0035] Preferably, the silicone-based toughening agent comprises a copolymer of methacrylate, acrylate and dimethylsiloxane.

[0036] In the present invention, the toughening agent can be selected, for example, from METABLEN of Mitsubishi Chemical. TM The S-type toughening agent includes, but is not limited to, S-2001, S-2501, S-2100, etc.

[0037] Preferably, the PBT / PC composition further comprises 0.01-1 part by weight of an auxiliary agent, for example, it can be 0.01 part, 0.05 part, 0.1 part, 0.2 part, 0.5 part, 0.8 part, 1 part, etc.

[0038] Preferably, the auxiliary agent comprises any one or a combination of at least two of an antioxidant, a lubricant or a drip retardant.

[0039] Preferably, the auxiliary agent comprises 0-0.5 part by weight of an antioxidant (for example, it can be 0 part, 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part, etc.), 0-1 part by weight of a lubricant (for example, it can be 0 part, 0.2 part, 0.4 part, 0.6 part, 0.8 part, 1 part, etc.) and 0-0.8 part by weight of a drip retardant (for example, it can be 0 part, 0.2 part, 0.4 part, 0.6 part, 0.8 part, etc.).

[0040] Preferably, the antioxidant comprises any one or a combination of at least two of a hindered phenol antioxidant, a phosphite antioxidant or a thio antioxidant.

[0041] Preferably, the lubricant comprises any one or a combination of at least two of low molecular weight polyethylene, oxidized polyethylene wax or ethylene acrylic acid copolymer.

[0042] Preferably, the rotational viscosity of the lubricant at 140 °C is 300-600 cps, for example, it can be 300 cps, 350 cps, 400 cps, 450 cps, 500 cps, 550 cps, 600 cps, etc., and the viscosity is obtained by testing according to ASTM D2196-2018 standard.

[0043] Preferably, the drip retardant comprises polytetrafluoroethylene.

[0044] In a second aspect, the present invention provides a preparation method of the PBT / PC composition according to the first aspect, and the preparation method comprises: mixing a PBT resin, a PC resin, a brominated PC, other bromine-based flame retardants, an antimony-based flame retardant, a phosphate ester flame retardant, a silicone-based toughening agent and optionally an auxiliary agent, and subjecting the mixture to melt extrusion granulation to obtain the PBT / PC composition.

[0045] Preferably, the PBT resin is dried before mixing.

[0046] Preferably, the drying temperature is 100 - 140°C, such as 100°C, 110°C, 120°C, 130°C, 140°C, etc., and the drying time is 3 - 5h, such as 3h, 3.5h, 4h, 4.5h, 5h, etc.

[0047] Preferably, the melt extrusion granulation is carried out using a twin - screw extruder.

[0048] Preferably, the temperature of the first zone of the twin - screw extruder is 30 - 200°C (such as 30°C, 50°C, 100°C, 150°C, 200°C, etc.), the temperature of the second zone is 220 - 260°C (such as 220°C, 230°C, 240°C, 250°C, 260°C, etc.), the temperature of the third zone is 220 - 260°C (such as 220°C, 230°C, 240°C, 250°C, 260°C, etc.), the temperature of the fourth zone is 200 - 240°C (such as 200°C, 210°C, 220°C, 230°C, 240°C, etc.), the temperature of the fifth zone is 170 - 240°C (such as 170°C, 180°C, 200°C, 220°C, 240°C, etc.), the temperature of the sixth zone is 170 - 230°C (such as 170°C, 180°C, 200°C, 220°C, 230°C, etc.), the temperature of the seventh zone is 170 - 230°C (such as 170°C, 180°C, 200°C, 220°C, 230°C, etc.), the temperature of the eighth zone is 170 - 230°C (such as 170°C, 180°C, 200°C, 220°C, 230°C, etc.), the temperature of the ninth zone is 170 - 240°C (such as 170°C, 180°C, 200°C, 220°C, 240°C, etc.), the temperature of the die head is 210 - 250°C (such as 210°C, 220°C, 240°C, 250°C, etc.), the total residence time is 1 - 3min (such as 1min, 1.5min, 2min, 2.5min, 3min, etc.), and the main machine speed is 300 - 600r / min (such as 300r / min, 350r / min, 400r / min, 450r / min, 500r / min, 550r / min, 600r / min, etc.).

[0049] In the third aspect, the present invention provides an application of the PBT / PC composition according to the first aspect in electronic components.

[0050] Compared with the prior art, the present invention has at least the following beneficial effects:

[0051] The PBT / PC composition provided by the present invention is combined with specific types and dosages, and the components can synergistically function together. The resulting product has good toughness, fluidity, flame retardancy and electrical properties. Specifically, at a thickness of 0.8 mm, it can pass the GWIT at 750 °C, the CTI at 250 V, its Izod notched impact is ≥175 J / m, the melt index at 270 °C / 2.16 kg is ≥15 g / 10 min, the resistance value is ≥645 MΩ / mm, which can well meet the requirements of material properties in the fields of connectors, terminal blocks, etc., solve the problem that the electrical properties of nylon materials decrease due to water absorption, and has high practical application value. Detailed Embodiments

[0052] To facilitate the understanding of the present invention, the following examples are listed. Those skilled in the art should understand that the said examples are only for helping to understand the present invention and should not be regarded as specific limitations to the present invention.

[0053] The material information used in the following examples is shown as follows:

[0054] Component A1: PBT GX112, with an intrinsic viscosity of 0.8 dl / g, purchased from Yangzi Petrochemical Co., Ltd.;

[0055] Component A2: PBT GX121, with an intrinsic viscosity of 1.0 dl / g, purchased from Yangzi Petrochemical Co., Ltd.;

[0056] Component B1: PC 1300-03NP, with a melt index of 3 g / 10 min, purchased from LG Chem, South Korea;

[0057] Component B2: PC 1300-22NP, with a melt index of 22 g / 10 min, purchased from LG Chem, South Korea;

[0058] Component C1: Brominated PC, PC CH6305 BR, with a bromine element mass content of 20%, purchased from Cangzhou Dahua Group Co., Ltd.

[0059] Component C2: Brominated PC, PC 105B, with a bromine element mass content of 26%, purchased from Sabic;

[0060] Component D1: Brominated epoxy, F-2100, purchased from Israel Chemicals;

[0061] Component D2: Brominated polystyrene, Phlamoon-103L, purchased from Taizhou Baili Chemical Co., Ltd.;

[0062] Component E1: Antimony white, S-05N, purchased from Hunan Yiyang Flash Star Antimony Industry Co., Ltd.;

[0063] Component F1: phosphate flame retardant, resorcinol bis[di(2,6-dimethylphenyl) phosphate], PX-200, purchased from Daihachi Chemical of Japan;

[0064] Component F2: phosphate flame retardant, hydroquinone bis(diphenyl phosphate), WSFR-PX-220, purchased from Zhejiang Wansheng Chemical Co., Ltd.;

[0065] Component G1: Silicone toughener, S-2001, copolymer of methacrylate, acrylate and dimethylsiloxane, purchased from Mitsubishi Chemical, Japan;

[0066] Component G2: Silicone toughener, S-2501, a copolymer of methacrylate, acrylate and dimethylsiloxane, purchased from Mitsubishi Chemical of Japan;

[0067] Component G3: butadiene toughening agent, M-521, purchased from Kaneka Chemical Industry Co., Ltd., Japan;

[0068] Component F: additives: antioxidant 1010, lubricant PETS, anti-dripping agent polytetrafluoroethylene, the mass ratio of the three is 1:6:3, all of which are commercially available products.

[0069] Examples 1-8, Comparative Examples 1-7

[0070] The above examples and comparative examples respectively provide a PBT / PC composition, and the types and weight proportions of the components are shown in Table 1-2 (“-” indicates that the formulation does not contain the component);

[0071] The preparation method of the PBT / PC composition comprises the following steps:

[0072] (1) drying the PBT resin at 120° C. for 4 h, and then mixing it with other components to obtain a mixed product;

[0073] (2) The mixed product is melt-extruded and granulated through a twin-screw extruder to obtain a PBT / PC composition; wherein the temperatures of zones 1 to 9 of the twin-screw extruder are set to 60° C., 230° C., 230° C., 230° C., 210° C., 200° C., 200° C., and 210° C., respectively, the die temperature is 230° C., the total residence time is 2 min, and the main engine speed is 450 r / min.

[0074] Performance Testing

[0075] The performance of the PBT / PC compositions provided in the above embodiments and comparative examples was tested, and the specific testing method is as follows:

[0076] Resistance test: Use a multimeter to test the resistance of the material at 1mm thickness. The sample needs to be adjusted for 24 hours at 23℃ and 50% RH before testing.

[0077] Glow-wire ignition temperature (GWIT): Test whether a 0.8 mm thick sample will ignite at 750 °C according to the UL94-2003 standard;

[0078] Comparative tracking index (CTI): Test according to the IEC 60112-2020 standard to see if the sample can resist the dripping of 50 drops of electrolyte without generating tracking marks at a test voltage of 250 V;

[0079] Izod impact strength with notched specimen: Test according to the ASTM D256 standard;

[0080] Melt index: Measured according to the ISO 1133 standard at 270 °C under a condition of 2.16 kg.

[0081] Table 1

[0082]

[0083]

[0084] Table 2

[0085]

[0086]

[0087] The test results show that the PBT / PC composition provided by the present invention has good flame retardancy and toughness, and also has good electrical properties and fluidity. Specifically, it can pass the GWIT at 750 °C, the CTI at 250 V, its Izod impact strength with notched specimen ≥ 175 J / m, the melt index at 270 °C / 2.16 kg ≥ 15 g / 10 min, and the resistance value ≥ 645 MΩ / mm at a thickness of 0.8 mm.

[0088] Compared with Example 1, when a butadiene-based toughening agent is used in Comparative Example 1, not only does the Izod impact strength with notched specimen of the material decrease and the fluidity become poor, but the product also ignites at 750 °C and the flame retardancy effect weakens.

[0089] Compared with Example 1, when any one of brominated PC, other bromine-based flame retardants, antimony-based flame retardants, and phosphate flame retardants is not contained in Comparative Examples 2-5, the flame retardancy effect of the product weakens and the fluidity becomes poor.

[0090] Compared with Example 1, when PC resin is not contained in Comparative Example 6, the flame retardancy effect of the product weakens and the Izod impact strength with notched specimen decreases.

[0091] The applicant declares that the above is only a specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by any person skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A PBT / PC composition, characterized in that: The PBT / PC composition comprises the following components in parts by weight:

2. The PBT / PC composition according to claim 1, characterized in that The intrinsic viscosity of the PBT resin is 0.73 to 1.3 dl / g; Preferably, the PC resin has a melt index of 2-25 g / 10 min at 300° C. and 1.2 kg.

3. The PBT / PC composition according to claim 1, characterized in that The brominated PC is a random copolymer of phosgene, tetrabromobisphenol A and bisphenol A; Preferably, the structural formula of the brominated PC is as follows: Among them, X:Y=1:2-1:

5.

4. The PBT / PC composition according to claim 1, characterized in that The other brominated flame retardants include any one or a combination of at least two of brominated epoxy, brominated polystyrene, decabromodiphenylethane, brominated polycarbonate, polypentabromobenzyl acrylate or imine bromide; Preferably, the antimony-based flame retardant includes any one of antimony white, sodium antimonate or antimony chloride, or a combination of at least two of them.

5. The PBT / PC composition according to claim 1, characterized in that The phosphate flame retardant includes any one of resorcinol bis[di(2,6-dimethylphenyl)phosphate], hydroquinone bis(diphenylphosphate) or triphenyl phosphate, or a combination of at least two thereof.

6. The PBT / PC composition according to claim 1, characterized in that The silicon-based toughening agent includes a copolymer of a (meth)acrylate monomer and a siloxane monomer; Preferably, the acrylic ester monomer includes any one of methyl methacrylate, ethyl acrylate or butyl acrylate, or a combination of at least two thereof; Preferably, the siloxane monomer includes any one or a combination of at least two of dimethylsiloxane, methylsiloxane or siloxane; Preferably, the silicon-based toughening agent includes a copolymer of methacrylate, acrylate and dimethylsiloxane.

7. The PBT / PC composition according to claim 1, characterized in that The PBT / PC composition further comprises 0.01-1 parts of auxiliary agent by weight; Preferably, the auxiliary agent includes any one or a combination of at least two of an antioxidant, a lubricant or an anti-dripping agent; Preferably, the auxiliary agent comprises 0-0.5 parts of antioxidant, 0-1 parts of lubricant and 0-0.8 parts of anti-dripping agent by weight.

8. The PBT / PC composition according to claim 7, characterized in that The antioxidant includes any one of a hindered phenol antioxidant, a phosphite antioxidant or a thio antioxidant or a combination of at least two thereof; Preferably, the lubricant comprises any one or a combination of at least two of low molecular weight polyethylene, oxidized polyethylene wax or ethylene acrylic acid copolymer; Preferably, the rotational viscosity of the lubricant at 140° C. is 300-600 cps; Preferably, the anti-drip agent comprises polytetrafluoroethylene.

9. A method for preparing a PBT / PC composition according to any one of claims 1 to 8, characterized in that: The preparation method comprises: mixing PBT resin, PC resin, brominated PC, other brominated flame retardants, antimony flame retardants, phosphate flame retardants, silicon toughening agents and optional auxiliary agents, and performing melt extrusion granulation to obtain the PBT / PC composition.

10. Use of the PBT / PC composition according to any one of claims 1 to 8 in electronic components.

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