Titanium alloy nano injection molding polyethylene glycol terephthalate composite material and application thereof

Abstract

The invention belongs to the field of composite materials, and discloses a nano injection molding polyethylene glycol terephthalate composite material capable of being used for titanium alloy and application of the nano injection molding polyethylene glycol terephthalate composite material. The composite material comprises the following components in percentage by weight: 24.7%-81.85% of PCR PET (Polymerase Chain Reaction Polyethylene Terephthalate); 3%-7% of PBT; 3%-10% of polyarylsulfone; 2%-8% of a reactive flexibilizer; 0.05% to 0.1% of zinc diethyl hypophosphite; 0.1%-0.2% of zinc oxide; 0-1% of an antioxidant; 0-1% of a release agent; and 10%-50% of glass fiber. The composite material provided by the invention can realize high PCR content, has high titanium alloy binding force, and is smooth in demolding and stable in process. The problem that the existing nano injection molding material cannot realize high PCR content is solved.

Description

Technical Field

[0001] The invention belongs to the field of composite materials, and particularly relates to a nano injection-molded polyethylene terephthalate composite material that can be used for titanium alloys and an application thereof. Background Art

[0002] In recent years, nano injection molding of the middle frame has become the mainstream process for mid-to-high-end mobile phones. Whether it is an aluminum alloy middle frame, a stainless steel middle frame, or a titanium alloy middle frame, the nano injection molding process can be used to realize the design of the antenna partition strip. Polybutylene terephthalate (PBT) is currently the most used plastic material in the nano injection molding process due to its good comprehensive performance. In addition, polyphenylene sulfide (PPS) and high-temperature polyamide (PPA) are also used in some products. With the enhancement of environmental awareness and the promulgation of relevant regulations, the environmental protection requirements of consumer electronic products for raw materials are gradually increasing. Plastic products produced with consumer recycled raw materials (PCR) are increasingly favored by the market. However, for the plastic materials used in nano injection molding, whether it is PBT, PPS or PPA, due to the lack of a single large-scale consumer market, the lack of PCR raw materials makes it difficult to produce PCR-type products. Some companies use the method of adding some PCR-grade polyethylene terephthalate (PET) to PBT products to achieve PCR in the final product. However, the PCR content obtained by this method is low, generally not more than 20%. Otherwise, due to the slow crystallization and easy thermal decomposition of PET, it will cause defects such as difficulty in injection molding and demolding, decreased material properties, etc., which seriously affect the performance of the product. Summary of the invention

[0003] In order to overcome the shortcomings and deficiencies of the above-mentioned prior art, the primary purpose of the present invention is to provide a polyethylene terephthalate composite material that can be used for titanium alloy nano-injection molding, which can achieve a high PCR content, has a high titanium alloy bonding force, and has smooth demolding and stable process. The problem that the current nano-injection molding materials cannot achieve a high PCR content is solved.

[0004] Another object of the present invention is to provide a method for preparing the above-mentioned nano-injection-molded polyethylene terephthalate composite material that can be used for titanium alloy.

[0005] Another object of the present invention is to provide the application of the above-mentioned nano-injection-molded polyethylene terephthalate composite material for titanium alloy in smart phones and consumer electronic products.

[0006] The purpose of the present invention is achieved through the following solutions:

[0007] A PET composite material that can be used for titanium alloy nano-injection molding comprises the following components in percentage by weight:

[0008]

[0009] Preferably, the melting point of the PCR PET is 245-260°C and the intrinsic viscosity is 0.7-0.9 dL / g.

[0010] Preferably, the intrinsic viscosity of the PBT is 0.6-0.8 dL / g.

[0011] Preferably, the PPSU is a powdered raw material, and its particle size is preferably less than 100 mesh.

[0012] Preferably, the reactive toughening agent is a toughening agent containing glycidyl ether, preferably ethylene methyl acrylate methacrylate glycidyl ether copolymer.

[0013] Preferably, the mass ratio of the diethyl zinc hypophosphite to zinc oxide is 1:2.

[0014] The antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant, preferably antioxidant 1010; the release agent is at least one of polyvinyl alcohol and a long-chain fatty acid ester.

[0015] A method for preparing the above-mentioned PET composite material that can be used for titanium alloy nano-injection molding comprises the following steps: mixing the components and extruding and granulating them through an extruder, and the granulation temperature is 200-280°C.

[0016] The above-mentioned PET composite material for titanium alloy nano-injection molding is used in the manufacture of mobile phones and consumer electronic products, especially in the nano-injection molding titanium alloy middle frame.

[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0018] The PET composite material of the present invention can achieve high PCR content, has high titanium alloy binding force, and has smooth demolding and stable process. At the same time, the preparation method of the present invention is simple and easy to implement, and is suitable for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the plastic test piece, where 1 represents the titanium alloy part and 2 represents the plastic part. DETAILED DESCRIPTION

[0020] The present invention is further described in detail below in conjunction with the examples and drawings, but the embodiments of the present invention are not limited thereto. If specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially. The details are as follows: PCR PET is Linuo PCR PET810-NA (intrinsic viscosity 0.8dL / g), PBT1 is Changchun Chemical 1200-211D (intrinsic viscosity 0.75dL / g), PBT2 is Bluestar Chemical PBT1100A (intrinsic viscosity 1.05dL / g), PPSU is Solvay Radel R-5000, glass fiber is Chongqing International ECS3031H, ethylene methyl acrylate methacrylate glycidyl ether copolymer is Arkema AX8900, antioxidant 1010 is Tianjin Lianlong 1010, release agent pentaerythritol tetrastearate (PETS) is purchased from Hubei Longxin Chemical Co., Ltd., zinc diethylphosphinate is Clariant OP950, and zinc oxide is Sinopharm analytical grade zinc oxide. The materials used in the examples are directly used without any treatment after purchase. The PPSU particles in the examples are PPSU particles that have not been treated after purchase. The PPSU powder is PPSU that has been ground after purchase, and the particle size range after grinding is less than 100 mesh.

[0021] The tensile strength in the following examples is tested using the ISO527 standard method, and the notched impact strength is tested using the ISO180 standard method.

[0022] The titanium alloy nano-injection molding sample used in the present invention is prepared by the following process: Grade 5 titanium alloy material, size specifications, length 45mm, width 18mm, thickness 1.6mm; surface treatment process: sequentially immerse in NaOH solution alkaline washing (2mol / L, 50℃, 20 seconds), hydrochloric acid corrosion (1.5mol / L, 35℃, 40 seconds), and ammonia solution (2mol / L, 30℃, 4 minutes), and then the immersed sample is cleaned with water and dried to obtain a titanium alloy sample with nanopores on the surface.

[0023] Preparation of the plastic titanium alloy test monolith used in the present invention:

[0024] The present invention refers to the method of Japanese Dacheng nano injection molding related patent (8057890) to prepare the plastic metal test integral part. Figure 1 This is a schematic diagram of the structure of the titanium alloy plastic test piece. The size of the titanium alloy sheet is 18mm×45mm×1.6mm, the size of the plastic part is 10mm×45mm×3mm, and the bonding area between the plastic and the titanium alloy is 0.5cm 2In all experiments, the injection molding maintained the same injection molding conditions, barrel temperature 250-280°C, mold temperature 150°C, and the plastic compound was injected onto the titanium alloy sheet to obtain a plastic titanium alloy test piece.

[0025] Plastic-metal bonding performance test:

[0026] The plastic-metal bonding strength test standard used in the present invention refers to the standard in Japanese Taisei Chemical Patent 8057890, and the bonding area between plastic and metal is 0.5 cm 2 , perform biaxial tensile test on the plastic metal test piece.

[0027] The processing performance test method is as follows: use a single-mouth 60*60*2mm mold, injection temperature 270C, mold temperature 150C, molding cycle 40s continuous injection 13 molds. Discard the first 3 molds and start counting from the 4th mold. If 10 molds can be automatically demolded, the processing performance is excellent. If 7-9 molds can be automatically demolded, the processing performance is average, and if 0-6 molds can be automatically demolded, the processing performance is poor.

[0028] Examples 1 to 13

[0029] The PET composite materials in Examples 1 to 13 were prepared by the following steps: weighing the components in corresponding amounts according to weight percentage, then mixing the components, and granulating the PET composites using a twin-screw extruder at a granulation temperature of 200 to 280° C. The weight percentages (%) of the components in Examples 1 to 11 and the various properties of the prepared PET composite materials are shown in Table 1 below.

[0030] Table 1. Product properties and processing properties of PET composites.

[0031]

[0032]

[0033] From the data in Table 1, it can be seen that when PBT and PPSU exist at the same time, the processing performance of the product can be significantly improved. However, the titanium alloy bonding strength is still insufficient (it is generally believed that 35MPa can meet most production needs). As in Examples 4 and 5, when zinc diethyl hypophosphite is added to the system, although the titanium alloy bonding strength can be improved, the tensile strength, notch impact and processing performance are all deteriorated. However, after adding ZnO on the basis of Example 5, not only the bonding strength of the product is greatly improved, but also good processing performance can be maintained. At the same time, from the comparison of Examples 8 and 12, it can be seen that powdered PPSU has better comprehensive performance than granular PPSU.

[0034] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A PET composite material that can be used for titanium alloy nano-injection molding, characterized in that The composition comprises the following components in weight percentage:

2. The PET composite material for titanium alloy nano-injection molding according to claim 1, characterized in that: The PCR PET has a melting point of 245-260°C and an intrinsic viscosity of 0.7-0.9 dL / g.

3. The PET composite material for titanium alloy nano-injection molding according to claim 1, characterized in that: The intrinsic viscosity of the PBT is 0.6-0.8 dL / g.

4. The PET composite material for titanium alloy nano-injection molding according to claim 1, characterized in that: The PPSU is a powdered raw material with a particle size of less than 100 meshes.

5. The PET composite material for titanium alloy nano-injection molding according to claim 1, characterized in that: The mass ratio of the diethyl zinc hypophosphite to zinc oxide is 1:

2.

6. The PET composite material for titanium alloy nano-injection molding according to claim 1, characterized in that: The reactive toughening agent is a toughening agent containing glycidyl ether, preferably ethylene methyl acrylate methacrylate glycidyl ether copolymer.

7. The PET composite material for titanium alloy nano-injection molding according to claim 1, characterized in that: The antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant; the release agent is at least one of polyvinyl alcohol and a long-chain fatty acid ester.

8. A method for preparing a PET composite material for titanium alloy nano-injection molding according to any one of claims 1 to 7, characterized in that The following steps are involved: The components are mixed and extruded into granules through an extruder at a granulation temperature of 200-280°C.

9. Use of the PET composite material for titanium alloy nano-injection molding according to any one of claims 1 to 7 in the manufacture of mobile phones and consumer electronic products.

10. Use of the PET composite material for titanium alloy nano-injection molding according to any one of claims 1 to 7 in a nano-injection molding titanium alloy middle frame.

Images