WO2022141602A1

WO2022141602A1 - Pc/abs composite material having high chemical resistance, and preparation method therefor

Info

Publication number: WO2022141602A1
Application number: PCT/CN2020/142582
Authority: WO
Inventors: 段浩; 朱从山; 司胜仁
Original assignee: 佳易容聚合物(上海)有限公司
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2022-07-07

Abstract

Provided are a PC/ABS composite material having high chemical resistance and a preparation method therefor. The composite material comprises the following components in percentage by weight: 60-85% of polycarbonate; 15-40% of ABS; 0.5-5% of a compatibilizer; and 3-10% of a rheology modifier. The preparation method comprises the following steps: mixing raw material components according to a certain ratio at room temperature, and melting and extruding by means of twin screws, so as to prepare a PC/ABS composite material that is easy to process, and has excellent mechanical properties and high chemical resistance. The preparation method therefor is also provided. The prepared composite material has excellent mechanical properties, is easy to process, and maintains high chemical resistance and good product appearance.

Description

High chemical resistance PC/ABS composite material and preparation method thereof

technical field

The invention belongs to the field of macromolecules, and in particular relates to a PC/ABS composite material with easy processing, excellent mechanical properties and high chemical resistance, a preparation method thereof, and a preparation method thereof.

Background technique

PC/ABS combines the comprehensive characteristics of PC (polycarbonate) and ABS (polyacrylonitrile-butadiene-styrene). Compared with PC, it improves fluidity, improves processing performance, and reduces product stress. Sensitivity and better thermal stability than ABS. Therefore, it can be used in many fields such as household appliances, office equipment, communication equipment, photographic equipment, medical equipment, construction and lighting appliances, aerospace, electronic computers, optical fibers and so on. Especially in automotive interiors, exteriors, lamps and other high-strength, high heat-resistant parts have been widely used.

In recent years, the PC/ABS market has maintained a growth rate of more than 10%. With the development of automobiles, home appliances and other industries, people's demand for more beautiful and higher-performance PC/ABS is increasing. PC/ABS alloy series materials not only need to have excellent mechanical properties, but also need to include a series of new characteristics such as hydrolysis resistance stability, spray-free, ultra-low humidity, and chemical resistance.

Especially with the improvement of the social aesthetic concept, PC/ABS needs to be painted on PC/ABS products in order to meet the customer's various needs for product weather resistance and aesthetics. Due to the poor chemical resistance of PC/ABS, it will cause defects such as product cracking, dimensional deformation of parts, and material embrittlement after painting, which limits its application in this area.

Generally speaking, PC molecular chain contains ester group, which is easy to absorb water and has poor chemical resistance, especially alkali resistance. Even in weak alkaline environment, it will degrade due to saponification. The resistance is large, the residual stress of the product is large, and the cracking of the product is aggravated after being eroded by chemical reagents. When the ester group of PC is subjected to long thermal processing conditions or strong shearing conditions, it will further promote free radical chain degradation of PC, resulting in poor solvent resistance of PC/ABS.

The prior art discloses a modified polycarbonate plastic, and the mass ratio of the components includes: 50 parts of polycarbonate, 2-4 parts of barium carbonate, 1-2 parts of barium sulfate, 1-2 parts of barium dioxide, 2-4 parts of methyl methacrylate, 1-2 parts of phenethyl ether, 1-2 parts of polystyrene, and 1-2 parts of silicone, through the above method, the modified polycarbonate plastic of the present invention has high strength and ductility Good toughness, high impact strength, good transparency, good corrosion resistance, excellent electrical properties, good self-lubrication, good solvent resistance, safety and practicality; the prior art discloses a light absorption function and solvent resistance. The cracked transparent polyester material, based on the total weight of 100%, the raw material composition includes: 65-99.5% of polyester resin; 0.4-30% of multifunctional auxiliary; 0.1-5% of processing auxiliary; The composite particles with multiple core-shell structures, including the core, the middle layer and the shell layer, provide a transparent polyester material that can simultaneously absorb ultraviolet light and blue light efficiently, and has excellent solvent cracking resistance, processing performance and high transmittance.

However, at present, there is no good solution to solve the solvent resistance problem of PC/ABS. Adding chemical-resistant components, such as highly crystalline materials (PBT, PA, etc.), improves the chemical resistance of the material. However, the first Too much addition of the three components will often lead to a decrease in the heat resistance and impact strength of the material; the end-capping method is used to improve the chemical resistance of PC, such as isocyanates, oxazolines, epoxy and dimethacrylates. Anhydrides. By reacting with polymer end groups in a step-by-step polymerization manner, the end groups of PC are reduced, thereby improving its chemical resistance, but the problem it brings is the loss of processability. Due to the poor processability of high-viscosity PC, the apparent Poor, its residual internal stress will also become a weak point in chemical resistance, which often requires increasing the processing temperature, resulting in thermal cracking losses.

Therefore, how to balance processability, mechanical properties and chemical resistance has become an important topic. How to simultaneously improve the chemical resistance of PC/ABS in a stable, simple and effective manner and improve mechanical properties and processability is even more important for the preparation of high The key to performance PC/ABS alloys.

technical problem

The purpose of the present invention is to propose a simple, effective, easy-to-use, easy-to-process, and easy-to-use PC/ABS alloy material in view of the above-mentioned problems in the prior art, which are difficult to meet the requirements of higher requirements and stability. , A PC/ABS composite material with excellent mechanical properties and high chemical resistance and a preparation method thereof.

technical solutions

The object of the present invention is achieved through the following technical solutions: the high chemical resistance PC/ABS composite material of the present invention is prepared from raw materials consisting of polycarbonate, ABS, a compatibilizer, and a modifier; the compatibilizer is aromatic Terpolymer of vinyl monomer, acrylonitrile-based monomer and glycidyl methacrylate (GMA); the modifier is copolymerized of aromatic vinyl monomer and acrylonitrile-based monomer binary copolymer.

In the preparation method of the above-mentioned high-chemical-resistant PC/ABS composite material, polycarbonate, ABS, a compatibilizer and a modifier are extruded through twin screws to obtain a high-chemical-resistant PC/ABS composite material.

In the present invention, the amount of compatibilizer is 0.5-5% of the weight of polycarbonate and ABS; the amount of modifier is 3-10% of the weight of polycarbonate and ABS; in polycarbonate and ABS, polycarbonate is The mass percentage is 60-85%, and the balance is ABS, which has the advantages of easy processing and excellent mechanical properties. In terms of weight percentage, each component of the present invention is as follows: polycarbonate 60-85%; ABS 15-40%; compatibilizer 0.5-5%; modifier 3-10%.

Preferably, the amount of the compatibilizer is 1-3% of the weight of polycarbonate and ABS; the amount of modifier is 6-8% of the weight of polycarbonate and ABS.

The compatibilizer of the present invention is a terpolymer obtained by copolymerizing an aromatic vinyl monomer, acrylonitrile-based monomer and glycidyl methacrylate (GMA); preferably, the number average of the terpolymer is The molecular weight is 50000-90000; preferably, in the terpolymer, the content of aromatic vinyl monomers is 50wt%-85wt%, the content of acrylonitrile-based monomers is 10wt%-40wt%, methacrylic acid shrinks The content of glyceride is the balance, for example, 0.3wt% to 10wt%, preferably 0.5wt% to 5wt%. Further preferably, the terpolymer is composed of terpolymers with different glycidyl methacrylate contents; it is beneficial to PC/ABS processing, can maintain good thermal stability, the compatibilizer itself is simple to prepare, and the polymerization process is easy to control, It has a wide range of downstream processing technology options, and also prevents excessive PC reaction to form cross-linking, which is not conducive to mechanical properties. Different content of GMA end capping reduces the end groups of PC, which is beneficial to improve its chemical resistance.

The modifier of the present invention is a binary copolymer obtained by copolymerizing an aromatic vinyl monomer and an acrylonitrile-based monomer; preferably, in the binary copolymer, the content of the acrylonitrile-based monomer is 15wt% to 50wt% %, and the content of aromatic vinyl monomers is the remainder; further preferably, in the binary copolymer, the content of acrylonitrile-based monomers is 20wt% to 35wt%, and the content of aromatic vinyl monomers is the remainder. quantity. Preferably, the weight average molecular weight of the binary copolymer is 5,000-40,000.

In the present invention, the aromatic vinyl monomers include styrene-based monomers, and the acrylonitrile-based monomers include acrylonitrile monomers or α-methacrylonitrile monomers; preferably, the styrene-based monomers The monomers include styrene monomer, α-methylstyrene monomer, α-chlorostyrene monomer or p-methylstyrene monomer, and the acrylonitrile-based monomer is acrylonitrile monomer; further Preferably, the styrene-based monomer is a styrene monomer. The terpolymer of the present invention includes ST-AN-GMA terpolymer, and the binary copolymer includes ST-AN copolymer.

The present invention provides a method for preparing the above-mentioned high-chemical-resistant PC/ABS composite material, comprising the following steps: after each component raw material is blended in proportion, extruded through twin-screw to obtain a high-chemical-resistant PC/ABS composite material, Specifically, the twin-screw extrusion processing temperature is controlled at 220~280°C, and the rotation speed is 180~600rpm. After discharging, the PC/ABS with easy processing, excellent mechanical properties and high chemical resistance is obtained after being water-cooled and pelletized by a pelletizer. composite material.

The composite material prepared by the invention has excellent chemical resistance, good mechanical properties, good appearance and good processability.

beneficial effect

Compared with the prior art, the present invention has the following beneficial effects: the terpolymer with compatibilizing effect of the present invention can react with PC, can effectively reduce the end group concentration, thereby effectively improving the chemical resistance of PC or PC/ABS Stability; easy to use, no need for master batching, no secondary pollution, and no side effects such as PC degradation.

The rheology modifier of the invention has excellent plasticizing effect, is easier to plasticize compared with similar products on the market, can be matched with high-viscosity PC, balances the excellent performance and processability of high-viscosity PC, and is highly resistant to chemicals. The preparation of the composite material provides a suitable method; it does not need to introduce other high crystalline materials of the third component, and thus does not bring about problems such as compatibility, the formula structure is simple, and the processing is convenient.

Description of drawings

FIG. 1 is a surface view of Example 4 after solvent swelling.

FIG. 2 is a surface view of Comparative Example 1 after solvent swelling.

Embodiments of the present invention

The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

The high-chemical-resistant PC/ABS composite material of the present invention is prepared from four types of raw materials: polycarbonate, ABS, ST-AN-GMA terpolymer and ST-AN binary copolymer, without adding other components.

In embodiment and comparative example: described polycarbonate selects low, medium and high viscosity polycarbonate respectively, the melt index of 300 ℃/1.2Kg is respectively 22 g/10min, 15g/10min, 5g/10min, Japan Emperor.

The ABS was purchased from Kumho PD190, Korea.

In the ST-AN-GMA terpolymer, the content of aromatic vinyl monomers is 50wt% to 85wt%, the content of acrylonitrile monomers is 10wt% to 40wt%, and the content of glycidyl methacrylate is is the remainder; the number-average molecular weight of the terpolymer is 50,000-90,000, and the melt index at 235°C/2.16kg is 5-15g/10min. The preferred terpolymer of the present invention is composed of terpolymers with different glycidyl methacrylate contents, and in the terpolymers with different glycidyl methacrylate contents, the glycidyl methacrylate content is 0.5wt %～3wt% of two or three kinds, most preferably, in the terpolymers with different glycidyl methacrylate contents, the glycidyl methacrylate content is 0.5wt%, 1 wt%, 2 Two or three of wt% and 3 wt%; the terpolymer is composed of a terpolymer with a content of 0.5% glycidyl methacrylate and a terpolymer with a content of 1% glycidyl methacrylate, Preferably, the terpolymer is composed of 0.5% glycidyl methacrylate content terpolymer and 1% glycidyl methacrylate content terpolymer in equal weight; the best mechanical properties and chemical resistance can be obtained. Effect.

In the ST-AN binary copolymer, the number average molecular weight is 5000-40000, the melt index at 190°C/5kg is 40-200 g/10min, the ST content is 65 wt%-75 wt%, and the AN content is 25 wt%～35wt%.

The specific components and weight percentages of each embodiment and comparative example are shown in Table 1. All raw materials are commercially available conventional products. Among them, ST-AN-GMA (GMA=0.5%), ST content is 59.5wt%, AN The content is 40wt%, the GMA content is 0.5wt%, and the number average molecular weight is 30000; in ST-AN-GMA (GMA=1%), the ST content is 59wt%, the AN content is 40wt%, the GMA content is 3wt%, and the number of The average molecular weight is 33000; in ST-AN-GMA (GMA=5%), the ST content is 55wt%, the AN content is 40wt%, the GMA content is 5wt%, and the number average molecular weight is 50000. There are three kinds of ST-AN binary copolymers: ST-AN (Mw=5000, AN=25wt%), ST-AN (Mw=20000, AN=25wt%), ST-AN (Mw=20000, AN=33wt%) %), ST-AN (Mw=40000, AN=25wt%).

The raw materials are conventionally mixed uniformly in proportion, and the processing temperature is controlled to be 190~230°C and the rotational speed is 180~600rpm through a twin-screw extruder. ABS composite material.

.

The above examples and comparative examples were tested for tensile strength (D638, 50 mm/min), notched impact strength (1/8 inch, ASTM D256) and chemical resistance according to conventional test methods. The results are shown in Table 2.

.

The chemical resistance test is as follows: after the particles are conventionally compressed (0.5mm), they are immersed in a mixture of ethanol and ethyl acetate with a volume ratio of 3:1 at room temperature, and taken out every 1 minute to observe whether there are cracks on the surface.

It can be seen from the results in Table 2 that the present invention is suitable for PCs with different viscosities, and has improved chemical resistance. In the present invention, the combination of modifier, compatibilizer and PC can make the PC/ABS composite material have both excellent resistance. Chemical and mechanical properties. Fig. 1 and Fig. 2 are respectively the observation of the surfaces of Example 4 and Comparative Example 1 after solvent swelling (time in Table 2). It can be seen that the surface of Example 4 has less obvious cracks. Chemical resistance and apparent properties; the melt index (260°C/5Kg) of the examples is 15-40g/10min.

.

In Example 11, ABS came from Takahashi Petrochemical, in which 15 wt % of butadiene, 25 wt % of acrylonitrile, and a weight-average molecular weight of 140,000; The test method in Table 3 is the same as that in Table 2.

To sum up, the PC/ABS composite material prepared by the present invention, which is easy to process, has excellent mechanical properties, and has high chemical resistance, has excellent electrical properties and mechanical properties.

In the prior art, high AN content is selected to improve chemical corrosion resistance and oil resistance, but the solubility parameter difference becomes larger and the compatibility is poor, and the mechanical properties decline seriously; the prior art adds chemical-resistant components, such as high crystallinity In order to improve the chemical resistance of the material (PBT, PA, etc.), the addition of too much third component will often lead to the reduction of heat resistance and impact strength of the material or cause new compatibility problems. , thereby affecting the loss of other mechanical properties; in addition, the prior art discloses that polycarbonate, ABS, ST-AN-GMA terpolymer, and ST-AN binary copolymer are extruded and granulated in the presence of a conductive agent, without The chemical resistance of the product is involved, and the mechanical properties of the modified product are lower than that of pure PC/ABS, especially the notched impact strength.

There are many specific application ways of the present invention, and the above are only the preferred embodiments of the present invention. It should be noted that the above embodiments are only used to illustrate the present invention, but not to limit the protection scope of the present invention. For those skilled in the art, without departing from the principle of the present invention, several improvements can also be made, and these improvements should also be regarded as the protection scope of the present invention.

Claims

A PC/ABS composite material with high chemical resistance, characterized in that the composite material comprises the following components by weight percentage:

Polycarbonate 60～85%

ABS 15～40%

Compatibilizer 0.5～5%

modifier 3～10%

The compatibilizer is a terpolymer formed by copolymerization of aromatic vinyl monomer, acrylonitrile monomer and glycidyl methacrylate; the rheology modifier is aromatic vinyl monomer, propylene A binary copolymer made of nitrile monomers.
The PC/ABS composite material with high chemical resistance according to claim 1, wherein, in the terpolymer, the content of the aromatic vinyl monomer is 50wt% to 85wt%, and the acrylonitrile monomer The content of the body is 10wt% to 40wt%, and the balance is the content of glycidyl methacrylate.
The PC/ABS composite material with high chemical resistance according to claim 2, wherein, in the terpolymer, the content of glycidyl methacrylate is 0.5wt% to 5wt%.
The PC/ABS composite material with high chemical resistance according to claim 1, wherein the number-average molecular weight of the terpolymer is 50,000-90,000, and the weight-average molecular weight of the binary copolymer is 5,000 ~50000.
The PC/ABS composite material with high chemical resistance according to claim 1, wherein, in the binary copolymer, the content of the aromatic vinyl monomer is 50wt% to 85wt%, and the acrylonitrile monomer The content is 15wt% to 50wt%.
The PC/ABS composite material with high chemical resistance according to claim 1, wherein the weight percentage of the compatibilizer is 1-3%.
The PC/ABS composite material with high chemical resistance according to claim 1, wherein the weight percent of the rheology modifier is 4-8%.
The method for preparing a PC/ABS composite material with high chemical resistance according to claim 1, characterized in that it comprises the steps of: mixing polycarbonate, ABS, compatibilizer and rheology modifier through twin-screw extrusion out to obtain the PC/ABS composite material with high chemical resistance.
The method for preparing a PC/ABS composite material with high chemical resistance according to claim 8, wherein the temperature of the screw extrusion is 220-280° C., and the rotational speed is 180-600 rpm.
The application of the high chemical resistance PC/ABS composite material of claim 1 in the preparation of chemical resistance materials.