CN112322015A

CN112322015A - Polycarbonate/polystyrene alloy and preparation method and application thereof

Info

Publication number: CN112322015A
Application number: CN202011112652.6A
Authority: CN
Inventors: 王培涛; 岑茵; 黄险波; 艾军伟; 丁超; 叶南飚
Original assignee: Kingfa Science and Technology Co Ltd
Current assignee: Kingfa Science and Technology Co Ltd
Priority date: 2020-10-16
Filing date: 2020-10-16
Publication date: 2021-02-05
Anticipated expiration: 2040-10-16
Also published as: WO2022077861A1; CN112322015B

Abstract

The invention discloses a polycarbonate/polystyrene alloy which comprises the following components in parts by weight: 80 parts of polycarbonate; 8-25 parts of polystyrene; 5-25 parts of carboxylic acid ionomer; rubber particle size distribution in polystyrene: the difference between the D (3, 2) value and the D (4,3) value is less than or equal to 0.5. The density and dielectric loss of the polycarbonate/polystyrene alloy are reduced by adding a certain amount of carboxylic acid-based ionomer to the polycarbonate/polystyrene alloy.

Description

Polycarbonate/polystyrene alloy and preparation method and application thereof

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a polycarbonate/polystyrene alloy and a preparation method and application thereof.

Background

Polycarbonates (PC for short) are high molecular polymers containing carbonate groups in the molecular chain, and are classified into various types, such as aliphatic, aromatic, aliphatic-aromatic, and the like, depending on the structure of the ester group. Due to the structural particularity of polycarbonate, the polycarbonate is the universal engineering plastic with the highest growth speed in five engineering plastics. Polycarbonate is a synthetic material that has begun to develop in the late fifties. The polycarbonate resin has outstanding impact resistance, creep resistance and dimensional stability, is widely applied to the fields of electronic and electric appliances, rail transit and aerospace, and has a dosage exceeding nylon in recent years, thereby jumping the leading position.

However, when the polycarbonate is applied to signal transmission equipment, the defect of high dielectric loss exists, and the transmission strength of signals can be affected. In order to solve the technical defects, polystyrene can be added to prepare the alloy. But the compatibility of polystyrene material and polycarbonate material is poor, and the problems of peeling and delamination of the product and deterioration of mechanical property exist.

Disclosure of Invention

The present invention is directed to overcoming the above-mentioned deficiencies and providing a polycarbonate/polystyrene alloy having a relatively low dielectric constant, while having the advantage of a relatively low density.

Another object of the present invention is to provide a method for preparing the polycarbonate/polystyrene alloy.

The invention is realized by the following technical scheme:

a polycarbonate/polystyrene alloy comprises the following components in parts by weight:

80 parts of polycarbonate;

8-25 parts of polystyrene;

5-25 parts of carboxylic acid ionomer;

rubber particle size distribution in polystyrene: the difference between the D (3, 2) value and the D (4,3) value is less than or equal to 0.5.

The rubber particle size distribution in polystyrene is obtained by a laser particle size analyzer test, and the smaller the difference value between the D (3, 2) value and the D (4,3) value is, the more round the rubber is.

Preferably, the weight ratio of polystyrene to carboxylic acid-based ionomer is from 3:1 to 1: 2.

the carboxylic acid group ionomer is an ethylene/methacrylic acid copolymer, wherein 40mol% -90mol% of carboxyl groups in methacrylic acid units are neutralized by metal ions, the melt index range is 0.5-15 g/10min, and the test conditions are 190 ℃ and 2.16 kg.

The metal ions are at least one of sodium ions, zinc ions, magnesium ions and potassium ions

The melt index of the polystyrene is 2-15 g/10min, and the test conditions are 200 ℃ and 5 kg.

The melt index of the polycarbonate is 3-22 g/10min, and the test conditions are 300 ℃ and 1.2 kg.

Polycarbonates, which are branched thermoplastic polymers or copolymers obtained by reaction of dihydroxy compounds or their mixtures with small amounts of polyhydroxy compounds and phosgene (phosgene) or carbonic acid diesters. The polycarbonate resin can be produced by a phosgene method (interfacial polymerization method) or a melt method (transesterification method). The polycarbonate resin is also provided by subjecting a polycarbonate resin produced by a melt process to a post-treatment for adjusting the amount of terminal hydroxyl groups.

In the polycarbonate segment obtained by the phosgene method reaction, the repeating unit is formed by the reaction of bisphenol A and phosgene. In the polycarbonate segment obtained by the transesterification process, the repeating units are formed by reacting diphenyl carbonate with bisphenol A.

0-2 parts of lubricant is also included according to the parts by weight.

The lubricant is at least one selected from stearate lubricant, fatty acid lubricant and stearate lubricant; the stearate lubricant is at least one selected from calcium stearate, magnesium stearate and zinc stearate; the fatty acid lubricant is at least one selected from fatty acid, fatty acid derivative and fatty acid ester; the stearate lubricant is at least one selected from glyceryl monostearate and pentaerythritol stearate.

The preparation method of the polycarbonate/polystyrene alloy comprises the steps of uniformly mixing the components according to the proportion, and then extruding and granulating the mixture by a double-screw extruder to obtain the polycarbonate composite material, wherein the temperature range of a screw is 190-250 ℃, and the rotating speed range is 180-500 r/min.

The application of the polycarbonate/polystyrene alloy is used for preparing plastic products of signal transmission electronic components.

The invention has the following beneficial effects:

according to the invention, the polystyrene parameter with a specific rubber distribution particle size is selected, and the carboxylic acid ionomer is added, so that the polycarbonate and the polystyrene can form a bicontinuous phase structure, and the structure enables the area of a phase interface formed between the polycarbonate and the polystyrene to be larger under the condition of a certain polystyrene content. Such a structure is advantageous in reducing dielectric loss and also in reducing alloy density.

Detailed Description

The present invention will be further illustrated by the following specific examples and comparative examples, which are preferred embodiments of the present invention, but the present invention is not limited to the following examples, and is not particularly limited to the types of raw materials of the components used in the following specific examples.

The raw materials used in the invention are as follows:

polycarbonate (C): the melt index was 5.7 g/10min, the test conditions were 300 ℃ and 1.2kg, PC WY-106BR, the monomers bisphenol A (BPA) and diphenyl carbonate (DPC), commercially available;

carboxylic acid group ionomer a: the main chain is ethylene/methacrylic acid copolymer, the melt index is 0.7g/10min, the test condition is 190 ℃, 2.16kg, 78mol percent of carboxyl in methacrylic acid unit is neutralized by sodium ion, and the copolymer is commercially available.

Carboxylic acid group ionomer B: the main chain is ethylene/methacrylic acid copolymer, the melt index is 4.5g/10min, the test condition is 190 ℃, 2.16kg, 45mol percent of carboxyl in methacrylic acid unit is neutralized by zinc ion, and the copolymer is commercially available.

Carboxylic acid group ionomer C: the main chain is ethylene/methacrylic acid copolymer, the melt index is 5.9g/10min, the test condition is 190 ℃, 2.16kg, 26mol percent of carboxyl in methacrylic acid unit is neutralized by zinc ions.

Polystyrene A: the melt index is 2.3g/10min, the test conditions are 200 ℃ and 5 kg; the difference between the D (3, 2) value and the D (4,3) value of the rubber particle size distribution was 0.2, and it was commercially available.

And (2) polystyrene B: the melt index is 4.5g/10min, the test conditions are 200 ℃ and 5 kg; the difference between the D (3, 2) value and the D (4,3) value of the rubber particle size distribution was 0.5, and it was commercially available.

Polystyrene C: the melt index is 7.3g/10min, the test conditions are 200 ℃ and 5 kg; the difference between the D (3, 2) value and the D (4,3) value of the rubber particle size distribution was 0.8, and it was commercially available.

Zinc stearate: ZINC STEARATE (BS-2818), commercially available;

the preparation methods of the polycarbonate polystyrene alloy of the examples and the comparative examples of the present invention are as follows: according to the proportion, after the carboxylic acid ionomer, the polycarbonate, the polystyrene and the zinc stearate are uniformly mixed, the mixture is extruded and granulated by a double-screw extruder to obtain the polycarbonate composite material, wherein the temperature range of a screw is 200-260 ℃, and the rotating speed range is 300-400 r/min.

The performance test method comprises the following steps:

(1) density: the test is carried out at normal temperature according to ISO 1183-1-2019 test standard.

(2) Dielectric loss: the test is carried out by the SPDR method according to IPC-TM-650 standard, and the test frequency is 2.5 GHz.

Table 1: EXAMPLES proportions (parts by weight) of polycarbonate-polystyrene alloy ingredients and test results

	Example 1	Example 2	Example 3	Example 4	Example 5	Example 6	Example 7
								Polycarbonate resin	80	80	80	80	80	80	80
Polystyrene A	25	18	12	10	8		12
								Polystyrene B						12
Carboxylic acid radical ionomers A	5	6	12	20	24	12	12
								Zinc stearate	0.2	0.2	0.2	0.2	0.2	0.2
Density of	1.156	1.152	1.150	1.147	1.150	1.148	1.149
								Dielectric loss	0.0044	0.0038	0.0034	0.0039	0.0042	0.0032	0.0034

From examples 1-5, it is preferred that the weight ratio of polystyrene to carboxylic acid-based ionomer is from 3:1 to 1: 2, a more stable bicontinuous phase structure can be formed in the resin matrix, and the density and the dielectric loss are further reduced.

Table 2: example 7 and comparative example polycarbonate polystyrene alloy respective component ratios (parts by weight) and test results

	Example 7	Comparative example 1	Comparative example 2	Comparative example 3	Comparative example 4
						Polycarbonate resin	80	80	80	80	80
Polystyrene A	12		12	4	12
						Polystyrene C		12
Carboxylic acid radical ionomers A		12	2	12
						Carboxylic acid radical ionomers B	12
Zinc stearate	0.2	0.2	0.2	0.2	0.2
						Density of	1.153	1.159	1.164	1.160	1.168
Dielectric loss	0.0033	0.0048	0.0050	0.0057	0.0053

As is clear from comparative example 1, the difference between the values of D (3, 2) and D (4,3) of the rubber particle size distribution of polystyrene is too large, and it is difficult to form a bicontinuous phase structure in the resin matrix, resulting in poor dielectric loss and density.

It is understood from comparative example 2/3 that when the compounding ratio is outside the range of the present invention, it is difficult to form a bicontinuous phase structure in the resin matrix.

Claims

1. The polycarbonate/polystyrene alloy is characterized by comprising the following components in parts by weight:

80 parts of polycarbonate;

8-25 parts of polystyrene;

5-25 parts of carboxylic acid ionomer;

2. The polycarbonate/polystyrene alloy of claim 1, wherein the weight ratio of polystyrene to carboxylic acid-based ionomer is from 3:1 to 1: 2.

3. the polycarbonate/polystyrene alloy of claim 1, wherein the carboxylic acid based ionomer is an ethylene/methacrylic acid based copolymer in which 40mol% to 90mol% of the carboxylic acid groups in the methacrylic acid units are neutralized with metal ions, and the melt index is in the range of 0.5 to 15 g/10min, under the test conditions of 190 ℃ and 2.16 kg.

4. The polycarbonate/polystyrene alloy of claim 3, wherein said metal ions are selected from at least one of sodium ions, zinc ions, magnesium ions, and potassium ions.

5. The polycarbonate/polystyrene alloy of claim 1, wherein the polystyrene has a melt index of 2 to 15 g/10min, and the test conditions are 200 ℃ and 5 kg.

6. The polycarbonate/polystyrene alloy of claim 1, wherein the polycarbonate has a melt index of 3 to 22 g/10min, and the test conditions are 300 ℃ and 1.2 kg.

7. The polycarbonate/polystyrene alloy of claim 1, further comprising 0-2 parts by weight of a lubricant; the lubricant is at least one selected from stearate lubricants, fatty acid lubricants and stearate lubricants.

8. The method for preparing the polycarbonate/polystyrene alloy as claimed in any one of claims 1 to 7, wherein the polycarbonate composite material is obtained by uniformly mixing the components according to the mixture ratio and then extruding and granulating the mixture by a double-screw extruder, wherein the temperature range of the screw is 190-250 ℃, and the rotating speed range is 180-500 r/min.

9. Use of the polycarbonate/polystyrene alloy of any of claims 1 to 7 for the preparation of plastic articles for signal transmission electronic components.