CN114836019A - A kind of polycarbonate composite material and preparation method thereof - Google Patents

Abstract

The invention provides a polycarbonate composite material, comprising the following raw materials in parts by weight: 55-90 parts of polycarbonate; 5-40 parts of basalt fiber; 2-10 parts of blocked isocyanate; and 1-5 parts of toughening agent; 0.1-2 parts of dispersant; 0.1-5 parts of lubricant; 0.1-5 parts of antioxidant. In the present invention, the blocked isocyanate is well compatible with the polycarbonate, so as to achieve the purpose of improving the mechanical properties and various mechanical properties of the polycarbonate without increasing the cost. The basalt fiber is well compatible with polycarbonate through the effect of modified blocked isocyanate, which improves the mechanical properties of polycarbonate. Its tensile strength is increased by nearly three times, elongation at break is increased by about three times, The notched impact strength is increased by about 2.5 times, the bending strength is increased by about 2.5 times, the water absorption rate of salt spray is decreased by nearly 10 times, and the high temperature resistance temperature is increased by about 15 °C. Significantly improved the properties of polycarbonate materials.

Description

A kind of polycarbonate composite material and preparation method thereof

technical field

The invention relates to the technical field of materials, in particular to a polycarbonate composite material and a preparation method thereof.

Background technique

Polycarbonate is a common material in our daily life, referred to as PC, which is a polymer containing carbonate groups in the molecular chain. It can be divided into aliphatic, aromatic, aliphatic-aromatic and other types according to the structure. type. Among them, the low mechanical properties of aliphatic and aliphatic-aromatic polycarbonates limit their application in engineering plastics, and only aromatic polycarbonates have been industrially produced. Bisphenol A (BPA) type PC polycarbonate material is a representative engineering plastic, not only has high transparency and good heat resistance, but also has excellent mechanical properties, high tensile strength, good impact performance, Has good dimensional stability. Although it has many advantages, its disadvantages are also obvious, such as: it is easy to age rapidly under long-term ultraviolet irradiation; the melt viscosity is large and the fluidity is poor, which makes the molding process difficult and prone to stress cracking. Although the application of polycarbonate in engineering plastics is increasing year by year, due to its own shortcomings, the application of polycarbonate is limited to a certain extent. With the increase of R&D investment and the continuous progress of technology, as people's requirements for its performance, the modification and enhancement of polycarbonate has become more and more hot, and people need to continue to explore. As a fiber reinforced material, basalt fiber has the characteristics of low cost, good fire resistance and excellent mechanical properties, while isocyanate, as a commonly used curing agent (compatibilizer), has strong activity and is easy to react. Blocked isocyanates are widely developed and applied, and the two ends of the isocyanate are blocked, thereby blocking the reaction between the hydroxyl groups, and can be unblocked under heating conditions, so that the isocyanate groups are released to participate in the reaction. The unsealing process makes the polycarbonate and basalt fibers combine well, thus preparing a composite material with excellent performance.

At present, there are some modification technologies for polycarbonate composite reinforcement materials. Covestro Germany Co., Ltd. has applied for a patent "polycarbonate composition" and applied for patent number 201880081846.9. However, this patent is cut from one or two relatively single angles. Polycarbonate will encounter various problems during the modification process. Therefore, it is necessary to solve the polycarbonate material from multiple angles. It is necessary to modify the approach encountered and thus propose a new solution.

SUMMARY OF THE INVENTION

In view of this, the technical problem to be solved by the present invention is to provide a polycarbonate composite material. The composite material provided by the present invention has good high temperature resistance, high water absorption and good mechanical properties.

The invention provides a polycarbonate composite material, comprising the following raw materials by weight:

Preferably, the polycarbonate is an aromatic polycarbonate; the molecular weight of the polycarbonate ranges from 25,000 to 30,000.

Preferably, the blocked isocyanate includes one or more of caprolactam blocked diisocyanate and blocked silane-containing polyisocyanate.

Preferably, the diisocyanate monomer in the caprolactam-terminated diisocyanate is selected from toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and one or more of lysine diisocyanate.

Preferably, the preparation method of the end-blocked silane-containing polyisocyanate is specifically:

a) condensation of isophorone diisocyanate and formic acid to obtain biuret polyisocyanate;

b) The biuret polyisocyanate is reacted with double-terminated hydroxyl polyether modified silicone oil, and ε-caprolactam is added to obtain a blocked polyisocyanate containing siloxane.

Preferably, the toughening agent is one or more of MBS toughening agent, Mitsubishi s2001, ARKEMA 8900 and ABS toughening agent.

The dispersant is one or more of 691, 693 or 694 from Euroceras, Germany.

The lubricant is one or more of PETS, GTS, GMS, silicone oil or white oil.

The antioxidant is one or more of hydroxyphenylbenzotriazole, ethyl acetohydroxamate and 168 phosphite.

The present invention provides a method for preparing a polycarbonate composite material according to any one of the above technical solutions, comprising the following steps:

A) Polycarbonate powder, blocked isocyanate, toughening agent, dispersant, antioxidant and lubricant are stirred to obtain a mixture;

B) the mixture is extruded to obtain extruded material; the extruded material and basalt fiber are impregnated and blended, and pulled out to obtain a polycarbonate-coated basalt fiber material;

C) granulating the polycarbonate-coated basalt fiber material, and compression molding to obtain the result.

Preferably, the mixing temperature in step A) is 70-100° C.; and the time is 50-90 min.

Preferably, the extrusion pressure in step B) is 4-6 MPa.

The feed rate of the blending is 300kg/h; the temperature of the blending is 180-250°C.

Preferably, the compression molding pressure in step C) is 8t, the compression speed is 6mm/s, and the compression time is 13s.

Compared with the prior art, the present invention provides a polycarbonate composite material, comprising the following raw materials by weight: 55-90 parts of polycarbonate; 5-40 parts of basalt fiber; 2-10 parts of blocked isocyanate; 1-5 parts of toughness agent; 0.1-2 parts of dispersant; 0.1-5 parts of lubricant; 0.1-5 parts of antioxidant. The invention achieves the purpose of improving the mechanical properties and various mechanical properties of the polycarbonate through the blocked isocyanates being well compatible with the polycarbonate without increasing the cost. The basalt fiber is well compatible with polycarbonate through the effect of modified blocked isocyanate, which improves the mechanical properties of polycarbonate. Its tensile strength is increased by nearly three times, elongation at break is increased by about three times, The notched impact strength is increased by about 2.5 times, the bending strength is increased by about 2.5 times, the water absorption rate of salt spray is decreased by nearly 10 times, and the high temperature resistance temperature is increased by about 15 °C. The performance of polycarbonate material is significantly improved, and its broadness, stability and safety in various fields are improved.

Detailed ways

The present invention provides a polycarbonate composite material and a preparation method thereof, and those skilled in the art can learn from the content of this article and appropriately improve the process parameters to achieve. It should be particularly pointed out that all similar replacements and modifications are obvious to those skilled in the art, and they all belong to the protection scope of the present invention. The method and application of the present invention have been described through the preferred embodiments, and it is obvious that relevant persons can make changes or appropriate changes and combinations of the methods and applications herein without departing from the content, spirit and scope of the present invention to realize and apply the present invention. Invention technology.

The invention adopts two methods of physical modification and chemical modification, adopts basalt composite material to strengthen polycarbonate, and uses caprolactam-modified blocked isocyanate to increase the compatibility of the two, and provides a better performance of polycarbonate/basalt fiber composites.

The invention provides a polycarbonate composite material, comprising the following raw materials by weight:

When the above-mentioned total amount is 100, the above-mentioned parts by weight are equivalent to the percentage by weight.

A polycarbonate composite material provided by the present invention comprises 55-90 parts by weight of polycarbonate; specifically, it can be 55, 60, 65, 70, 75, 80, 85 or 90 parts by weight; point value.

The polycarbonate of the present invention is an aromatic polycarbonate; the molecular weight of the polycarbonate ranges from 25,000 to 30,000.

The polycarbonate composite material provided by the present invention includes 5-40 parts by weight of basalt fibers; specifically, it can be 5, 10, 20, 25, 30, 35 or 40 parts by weight; or a point value between any of the above.

The basalt fiber of the present invention is the 816 (2400) model produced by Sichuan Qianyi Composite Materials Co., Ltd.

The polycarbonate composite material provided by the present invention comprises 2-10 parts by weight of blocked isocyanate; preferably 2-8 parts by weight of blocked isocyanate; more preferably 2-6 parts by weight of blocked isocyanate; , 4, 5, or 6 parts by weight; or a point value between any of the above.

The blocked isocyanates of the present invention include one or more of caprolactam-blocked diisocyanates and blocked silane-containing polyisocyanates; more preferably, caprolactam-blocked diisocyanates and blocked silane-containing polyisocyanates are included. Wherein, the mass ratio of the caprolactam-terminated diisocyanate and the blocked silane-containing polyisocyanate is (1-2): (0-2); specifically, it may be 1:1; 2:0.

Specifically, the diisocyanate monomer in the caprolactam-terminated diisocyanate is selected from toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and one or more of lysine diisocyanate.

In some preferred embodiments of the present invention, the preparation method of the caprolactam-terminated diisocyanate is specifically:

The ε-caprolactam-toluene solution and stannous octoate were added to a four-necked flask equipped with a reflux condenser, a stirrer, a dropping funnel and a nitrogen protection, and the temperature was raised to a reaction temperature of 50-100°C. The diisocyanate monomer solution of 0.5mol/L-2mol/L is added dropwise to the four-necked flask within a certain period of time 1-10min, and the reaction solution is transferred to the beaker while the reaction is hot. After cooling, add an appropriate amount of petroleum ether and stir for a while to separate out a large amount of white solids. Suction filtration and rinse the filter cake with a small amount of frozen petroleum ether. The filter cake obtained is placed in a vacuum drying oven at 60 °C for constant temperature drying to obtain a white powdery solid crude product, which is purified to obtain the product.

In some preferred embodiments of the present invention, the preparation method of the blocked silane-containing polyisocyanate is specifically:

a) isophorone diisocyanate and formic acid are condensed at 50～80℃ to obtain biuret polyisocyanate;

b) After the biuret polyisocyanate and the double-terminated hydroxyl polyether modified silicone oil were reacted at 65 °C for 1 h, ε-caprolactam was added to continue the reaction for 6 h, the solvent was removed by rotary evaporation, and vacuum dried at 50 °C for 5 h to obtain a sealant. Siloxane terminated polyisocyanates.

A polycarbonate composite material provided by the present invention includes 1 to 5 parts by weight of a toughening agent; specifically, it can be 1, 2, 3, 4, or 5 parts by weight; or a point value between any of the above two.

The toughening agent of the present invention is one or more of MBS toughening agent, Mitsubishi s2001, ARKEMA 8900 and ABS toughening agent; more preferably, it is two kinds of MBS toughening agent, Mitsubishi s2001, ARKEMA 8900 and ABS toughening agent species or two or more;

The polycarbonate composite material provided by the present invention comprises 0.1-2 parts by weight of dispersant; preferably 0.1-1 part by weight; specifically, 0.1, 0.2, 0.3, 0.4, 0.5 or 1 part by weight; or any two of the above point value between.

The dispersant of the present invention is one or more of 691, 693 or 694 of euroceras in Germany.

The polycarbonate composite material provided by the present invention comprises 0.1-5 parts by weight of lubricant; preferably 0.1-4 parts by weight; more preferably 0.2-3 parts by weight; most preferably 0.3-2 parts by weight;

The lubricant of the present invention is one or more of PETS, GTS, GMS, silicone oil or white oil.

The polycarbonate composite material provided by the present invention includes 0.1-5 parts by weight of antioxidant. Preferably, it is 0.5 to 4 parts by weight; more preferably, it is 1 to 3 parts by weight.

The antioxidant of the present invention is one or more of hydroxyphenylbenzotriazole, ethyl acetohydroxamate and 168 phosphite.

The present invention provides a method for preparing a polycarbonate composite material according to any one of the above technical solutions, comprising the following steps:

A) Polycarbonate powder, blocked isocyanate, toughening agent, dispersant, antioxidant and lubricant are stirred to obtain a mixture;

B) the mixture is extruded to obtain extruded material; the extruded material and basalt fiber are impregnated and blended, and pulled out to obtain a polycarbonate-coated basalt fiber material;

C) granulating the polycarbonate-coated basalt fiber material, and compression molding to obtain the result.

The preparation method of the polycarbonate composite material provided by the present invention firstly stirs the polycarbonate powder, blocked isocyanate, toughening agent, dispersing agent, antioxidant and lubricant to obtain a mixture. Preferably, the mixture is uniformly mixed at 70 to 100° C. for 50 to 90 minutes in a low-speed mixer, and then dewatered and dried at 105° C.

The present invention has clearly described the above-mentioned components and specific ratios, and will not be repeated here.

The mixture is extruded to obtain extrudates.

The extrusion pressure of the present invention is 4-6MPa.

Impregnating and blending the extruded material and basalt fiber, and pulling it out to obtain a polycarbonate-coated basalt fiber material;

By controlling the feeding speed, the basalt fiber and the mixed A material are blended in a dipping mold at a temperature of 180-250 °C, and directly pulled out after blending to form a polycarbonate-coated basalt fiber material.

The feed rate of the blending in the present invention is 300kg/h and the temperature of the blending is 180-250°C.

The polycarbonate-coated basalt fiber material is granulated and compression-molded to obtain it.

The compression molding pressure of the present invention is 8t, the compression speed is 6mm/s, and the compression time is 13s.

This was cut to obtain pellets and compression-molded.

The invention provides a polycarbonate composite material, comprising the following raw materials in parts by weight: 55-90 parts of polycarbonate; 5-40 parts of basalt fiber; 2-10 parts of blocked isocyanate; and 1-5 parts of toughening agent; 0.1-2 parts of dispersant; 0.1-5 parts of lubricant; 0.1-5 parts of antioxidant. The invention achieves the purpose of improving the mechanical properties and various mechanical properties of the polycarbonate through the blocked isocyanates being well compatible with the polycarbonate without increasing the cost. The basalt fiber is well compatible with polycarbonate through the effect of modified blocked isocyanate, which improves the mechanical properties of polycarbonate. Its tensile strength is increased by nearly three times, elongation at break is increased by about three times, The notched impact strength is increased by about 2.5 times, the bending strength is increased by about 2.5 times, the water absorption rate of salt spray is decreased by nearly 10 times, and the high temperature resistance temperature is increased by about 15 °C. The performance of polycarbonate material is significantly improved, and its broadness, stability and safety in various fields are improved.

In order to further illustrate the present invention, a polycarbonate composite material provided by the present invention and its preparation method are described in detail below with reference to the examples.

Examples 1 to 8

Preparation method: Add polycarbonate powder, blocked isocyanate, toughening agent, dispersant, antioxidant, lubricant, etc. into a low-speed mixer, mix uniformly at 90°C for 80 minutes, and then dewater and dry at 105°C. Add the twin-screw extruder and extrude it at 4-6MPa to obtain the A material. By controlling the feeding speed to 300kg/h, the basalt fiber and the mixed A material are blended in the dipping die, and the temperature is 180～ 250°C, directly pulled out after blending to form a polycarbonate-coated basalt fiber material, which was then cut to obtain pellets, which were compression molded under the conditions of a pressure of 8t, a compression speed of 6mm/s, and a compression time of 13s.

Table 1

Table 2: The test results of the mechanical properties of the materials of the embodiments 1-8#

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. The polycarbonate composite material is characterized by comprising the following raw materials in parts by weight:

2. the material of claim 1, wherein the polycarbonate is an aromatic polycarbonate; the molecular weight range of the polycarbonate is 25000-30000.

3. The material of claim 1, wherein the blocked isocyanate comprises one or more of a caprolactam blocked diisocyanate and a blocked silane-containing polyisocyanate.

4. A material according to claim 3, wherein the diisocyanate monomer in the caprolactam-terminated diisocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and lysine diisocyanate.

5. The material according to claim 3, wherein the blocked silane-containing polyisocyanate is prepared by a method comprising:

a) condensing isophorone diisocyanate and formic acid to obtain biuret polyisocyanate;

b) reacting the biuret polyisocyanate with double-end hydroxyl polyether modified silicone oil, and adding epsilon-caprolactam to obtain the blocked siloxane-containing polyisocyanate.

6. The material according to claim 1,

the toughening agent is one or more of MBS toughening agent, Mitsubishi 2001, ARKEMA 8900 and ABS toughening agent;

the dispersant is one or more of 691, 693 or 694 of euroceras Germany;

the lubricant is one or more of PETS, GTS, GMS, silicone oil or white oil;

the antioxidant is one or more of hydroxyphenyl benzotriazole, ethyl acetylhydroxamate and 168 phosphite antioxidant.

7. A method for preparing the polycarbonate composite material as defined in any one of claims 1 to 6, comprising the steps of:

A) stirring polycarbonate powder, blocked isocyanate, a toughening agent, a dispersing agent, an antioxidant and a lubricating agent to obtain a mixture;

B) extruding the mixture to obtain an extruded material; dipping, blending and pulling out the extruded material and the basalt fiber to obtain a polycarbonate-coated basalt fiber material;

C) and granulating the basalt fiber material coated by the polycarbonate, and performing compression molding to obtain the polycarbonate-coated basalt fiber material.

8. The method according to claim 7, wherein the temperature of the mixing in step A) is 70 to 100 ℃; the time is 50-90 min.

9. The method according to claim 7, wherein the extrusion pressure in step B) is 4 to 6 MPa;

the feeding speed of the blending is 300 kg/h; the blending temperature is 180-250 ℃.

10. The method of claim 7, wherein the compression molding in step C) is carried out at a compression speed of 6mm/s for a compression time of 13s at a pressure of 8 t.