CN111019317B

CN111019317B - Low-melting-point transparent hydrolysis-resistant modified PC material and preparation method thereof

Info

Publication number: CN111019317B
Application number: CN201911370386.4A
Authority: CN
Inventors: 王晶; 张天荣; 王帅; 王凯; 王明义
Original assignee: Shanghai Juwei New Material Co ltd
Current assignee: Shanghai Juwei New Material Co ltd
Priority date: 2019-12-26
Filing date: 2019-12-26
Publication date: 2022-04-15
Anticipated expiration: 2039-12-26
Also published as: CN111019317A

Abstract

The invention discloses a low-melting-point transparent hydrolysis-resistant modified PC material and a preparation method thereof, wherein the low-melting-point transparent hydrolysis-resistant modified PC material comprises the following components in parts by weight: 80-100 parts of polycarbonate resin, 5-15 parts of polystyrene copolymer, 1-3 parts of hydrolysis resistance agent, 0-0.3 part of antioxidant and 0-0.2 part of light stabilizer; according to the invention, the hydrolysis resistance agent is added, so that the integral lubricating property of the material is improved, the hydrolysis resistance modified PC material with excellent performance is obtained, the transparency and the thermal hydrolysis resistance of the product are ensured by controlling the proportion of the raw materials, the quality of the material is improved, and the application range of the material is widened.

Description

Low-melting-point transparent hydrolysis-resistant modified PC material and preparation method thereof

Technical Field

The invention relates to the technical field of high polymer material modification, in particular to a low-melting-point transparent hydrolysis-resistant modified PC material and a preparation method thereof.

Background

Polycarbonate (PC) is a general engineering plastic with excellent mechanical properties, electrical properties and heat resistance, is especially known as excellent impact strength and creep resistance, has high light transmittance, low water absorption and stable product size, and is the general engineering plastic with the highest production and application quantity growth speed among five engineering plastics.

Because of the wide application of PC materials, the specific requirements of different products are different, and the performance needs to be improved to meet the use requirements on the basis of the original material performance. The traditional PC material has high injection molding temperature, can generate serious trailing phenomenon with a matching part when secondary injection molding is carried out, is not beneficial to product forming, and thus the melting point of the PC material is required to be reduced, so that the injection molding temperature is reduced, and further the processing requirement is met, but the transparency, the high temperature resistance and the moisture resistance of the material are seriously influenced after the melting point of the PC material is changed, and the application range of the material is limited.

Therefore, it is an urgent need to solve the problem of providing a modified PC that can lower the PC temperature while maintaining its transparency and high temperature and humidity resistance, and the preparation thereof.

Disclosure of Invention

In view of the above, the invention provides a low-melting-point transparent hydrolysis-resistant modified PC material and a preparation method thereof, which start from raw material selection and formula combination, and study on a base material to improve the overall performance of the material, improve the overall lubricating performance of the material to ensure that the material has excellent hydrolysis resistance, improve the quality of the material, and widen the application range of the material.

In order to achieve the purpose, the invention adopts the following technical scheme:

a low-melting-point transparent hydrolysis-resistant modified PC material comprises the following components in parts by weight: 80-100 parts of polycarbonate resin, 5-15 parts of polystyrene copolymer, 1-3 parts of hydrolysis resistance agent, 0-0.3 part of antioxidant and 0-0.2 part of light stabilizer.

Preferably, the polycarbonate is bisphenol A type resin with the molecular weight of 24000-27000.

Preferably, the polystyrene copolymer is an emulsion polymerization resin.

Preferably, the hydrolysis resistant agent is one or more of castor oil, carbodiimide or dicarboxylic acid.

Preferably, the antioxidant is a phosphite antioxidant.

Preferably, the light stabilizer is a benzotriazole light stabilizer.

The invention also provides a preparation method of the modified PC material, which comprises the following steps:

(1) weighing polycarbonate resin, polystyrene copolymer, hydrolysis resistance agent, antioxidant and light stabilizer in proportion, and respectively drying to obtain dry raw materials;

(2) and (2) uniformly mixing the dried raw materials in the step (1), adding the mixture into a double-screw extruder, controlling the temperature of an extruder barrel and the rotating speed of a screw, and extruding, cooling and granulating to obtain a finished product.

Preferably, the temperature in the extruder barrel from the feed inlet to the discharge outlet is 230 ℃, 250 ℃, 300 ℃, 305 ℃ and 290 ℃ in sequence, and the rotating speed of the screw is 300 r/min.

Through the technical scheme, compared with the prior art, the invention provides the low-melting-point transparent hydrolysis-resistant modified PC material and the preparation method thereof, the added hydrolysis-resistant agent is used for improving the integral lubricating property of the material and improving the hydrolysis resistance of the material, the transparency of the product is not affected by adjusting and limiting the adding types and the adding proportions of the materials, the high-melting-point transparent hydrolysis-resistant modified PC material also has high pyrolysis resistance, the preparation process is simple and convenient and easy to control, and the high popularization value is realized.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The modified PC material is prepared by the following method:

(2) and (2) uniformly mixing the dried raw materials in the step (1), adding the uniformly mixed raw materials into a double-screw extruder with a screw diameter of 35mm and a length-diameter ratio L/D of 36, controlling the temperature of a main machine barrel in a segmented manner, controlling the rotating speed of the screw from a feed inlet to a machine head outlet at 230 ℃, 250 ℃, 300 ℃, 305 ℃, 290 ℃, 300r/min, and cooling extruded strips through a water tank and then pelletizing to obtain the product.

Wherein, polycarbonate resin (PC): bisphenol A type resin having molecular weight of 24000-27000;

polystyrene (GPPS): emulsion synthetic resin, PG 383M;

hydrolysis resistance agent: 1) castor oil: colorless or light yellow viscous liquid;

2) carbodiimide (B): rhine chemistry, hydrolysis resistant agent Stabaxol P;

3) dimer acid: chemical purity, 99.9%;

antioxidant: phosphites 168;

light stabilizer: benzotriazoles 234;

in the performance test of the prepared product, firstly, the injection molded sample bar is immediately put into a glass drier and is placed at room temperature for at least 24 hours, and then the test is carried out, wherein the test standards are as follows:

1) transparency: evaluated according to ASTM D1003;

2) tensile strength: evaluated according to the method of ISO 527-2.

Specific examples and test results are shown in tables 1-4 below:

table 1.

As can be seen from the test results in Table 1, the injection molding temperature of the modified PC material can be reduced and the melting point can be reduced by adding the polystyrene GPPS material into the polycarbonate PC material, the injection molding temperature of common PC is generally 270-310 ℃, while the injection molding temperature of examples 1-3 is reduced; because the refractive index of GPPS is similar to that of PC, the high transparency is still maintained; by adding different substances, the hydrolysis resistance of the whole material is improved, the castor oil has the best effect, and the castor oil is a lubricant with excellent lubricating effect, and can play a role in hydrolysis resistance when added into the transparent PC material, so that the hydrolysis resistance of the whole material is improved.

Table 2.

From the test results of the above examples and comparative examples, it can be seen that the injection molding temperature is significantly decreased as the addition amount of the GPPS material is increased, but the transparency of the material is rapidly decreased and poor compatibility is exhibited at a higher content, and it can be seen that the addition amount of the GPPS material should be appropriate.

Table 3.

From the test results of the above examples, it can be seen that the hydrolysis resistance is slightly increased with the increase of the content of castor oil, but the transparency is obviously reduced, and the injection molding temperature is increased, which indicates that the addition of a large amount of castor oil causes the chain extension reaction of the whole material, thereby increasing the injection molding temperature.

Table 4.

As can be seen from the test results of the above examples, increasing the contents of the antioxidant 168 and the light stabilizer 234 decreases the transparency of the material and increases the aging resistance of the material.

The hydrolysis resistance agent added in the invention improves the integral lubricating property of the material, and simultaneously obtains the hydrolysis resistance modified PC material with excellent performance, thereby improving the quality of the material and widening the application range of the material.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low-melting-point transparent hydrolysis-resistant modified PC material is characterized by comprising the following components in parts by weight: 80-100 parts of polycarbonate resin, 5-15 parts of polystyrene, 1-3 parts of hydrolysis resistance agent, 0-0.3 part of antioxidant and 0.1-0.2 part of light stabilizer;

the hydrolysis resistant agent is castor oil, the antioxidant is phosphite 168, and the light stabilizer is benzotriazole 234.

2. The low-melting-point transparent hydrolysis-resistant modified PC material as claimed in claim 1, wherein the polycarbonate is bisphenol A type resin with molecular weight of 24000-27000.

3. The low melting point transparent hydrolysis-resistant modified PC material of claim 2, wherein the polystyrene is an emulsion polymerization resin.

4. A method for preparing the low-melting-point transparent hydrolysis-resistant modified PC material according to any one of claims 1 to 3, comprising the steps of:

(1) weighing polycarbonate resin, polystyrene, a hydrolysis resistance agent, an antioxidant and a light stabilizer according to a proportion, and then respectively drying to obtain dry raw materials;

5. The method for preparing the low-melting-point transparent hydrolysis-resistant modified PC material as claimed in claim 4, wherein the temperature of the extruder barrel from the feed inlet to the discharge outlet is 230 ℃, 250 ℃, 300 ℃, 305 ℃, 290 ℃ in sequence, and the screw rotation speed is 300 r/min.