CN107474531B

CN107474531B - Glass fiber-graphene-carbon nanotube mixed filled PA66/PC composite material and preparation method thereof

Info

Publication number: CN107474531B
Application number: CN201710648520.7A
Authority: CN
Inventors: 卢运来
Original assignee: Hubei Yunlai Plastic Technology Co ltd
Current assignee: Hubei Yunlai Plastic Technology Co ltd
Priority date: 2017-08-01
Filing date: 2017-08-01
Publication date: 2020-11-10
Anticipated expiration: 2037-08-01
Also published as: CN107474531A

Abstract

The invention relates to a glass fiber-graphene-carbon nanotube mixed filled PA66/PC composite material and a preparation method thereof, wherein the composite material is composed of a PA66-PC matrix, a modified graphene-carbon nanotube mixture, glass fibers, a silane coupling agent and epoxy resin. The injection product prepared by the composite material has good surface quality, internal layering phenomenon and excellent heat conduction and mechanical properties.

Description

Glass fiber-graphene-carbon nanotube mixed filled PA66/PC composite material and preparation method thereof

Technical Field

The invention belongs to the technical field of engineering plastics, and particularly relates to a glass fiber-graphene-carbon nanotube mixed-filled PA66/PC composite material and a preparation method thereof.

Background

PA66 (polyamide 66 or nylon 66) has better impact resistance and higher strength, and is widely applied to manufacturing parts of mechanical, automobile, chemical and electrical devices, such as gears, rollers, pulleys, roller shafts, impellers in pump bodies, fan blades, high-pressure sealing rings, valve seats, gaskets, bushings, various handles, supporting frames, inner layers of wire wraps and the like. The PA66 has good wear resistance, heat resistance, oil resistance and chemical resistance, the water absorption rate and the shrinkage rate of raw materials are greatly reduced, the shrinkage rate of the PA66 is 1-2%, the shrinkage rate can be reduced to 0.2-1% by adding glass fiber, and the surface defects such as fiber floating, glass fiber leakage and the like are easily generated on the surface of a product after the glass fiber is added.

PA66 can be blended with other polymers (such as PC) to meet special requirements of different industries, and is widely used as a substitute for traditional materials such as metal, wood and the like. Polycarbonate (PC) has outstanding impact resistance and creep resistance, good cold resistance and heat resistance, low water absorption and stable product size. But also has the defects of poor processing fluidity, poor solvent resistance, easy stress cracking, sensitivity to notches and the like. The nylon (PA) has high mechanical strength and good melt fluidity and oil resistance, so that the PC and PA materials have good complementarity in performance. The PA66/PC composite material generally has the characteristics of good impact toughness, excellent chemical corrosion resistance and the like, and is an important synthetic material.

Disclosure of Invention

The invention aims to provide a glass fiber-graphene-carbon nanotube mixed and filled PA66/PC composite material, which is prepared from raw materials including a matrix composed of PA66 and PC, a modified graphene mixture, glass fibers, a silane coupling agent and epoxy resin, wherein the weight ratio of the matrix to the glass fibers to the modified graphene mixture is 7:3:0.6-1.2, and the use amounts of the silane coupling agent and the epoxy resin are 0.1-0.2% and 0.2% of the weight of the composite material respectively, wherein the modified graphene mixture is prepared by uniformly mixing graphene and carbon nanotubes according to the mass ratio of 1-5:1, adding the mixture into a concentrated sulfuric acid solution with the mass fraction of 82-86%, stirring at normal temperature for 7-14min, filtering, neutralizing, washing, redispersing an ethanol solution, standing, and freeze-drying.

In the scheme, the weight ratio of the PA66 to the PC in the matrix is 1: 0.5-1.5.

In the above scheme, the silane coupling agent is Si 550.

The invention also aims to provide a preparation method of the glass fiber-graphene-carbon nanotube mixed filled PA66/PC composite material, which specifically comprises the following steps: (1) uniformly mixing graphene and carbon nanotubes in proportion, adding the graphene mixture into a concentrated sulfuric acid solution, stirring at normal temperature for 7-14min, adding water to dilute, filtering, washing filter residues with an alkali solution for multiple times, washing with water to be neutral, dispersing the filter residues in an ethanol solution, adding glass fibers, stirring, refrigerating at 0-4 ℃ for 12-18h, and freeze-drying to obtain a modified graphene-glass fiber mixture; (2) and uniformly mixing the modified graphene-glass fiber mixture, the PA66/PC matrix, the silane coupling agent and the epoxy resin, and performing melt granulation by a double-screw extruder to obtain the modified graphene-glass fiber composite material.

In the scheme, graphene and carbon nano tubes are mixed according to the mass ratio of 1-5:1, the mass fraction of concentrated sulfuric acid is 82-86%, the alkali solution is 0.1-0.3mol/L NaOH solution, and the volume fraction of the ethanol solution is 40-60%.

In the scheme, the weight ratio of the PA66/PC matrix to the glass fiber to the modified graphene mixture is 7:3:0.6-1.2, and the use amounts of the silane coupling agent and the epoxy resin are respectively 0.1-0.2% and 0.2% of the weight of the composite material.

In the scheme, the length-diameter ratio of a double-screw extruder used for extrusion granulation is 1:30-40, the rotating speed is 330rad/s, and the melting temperature is 240-.

Compared with the prior art, the invention has the following beneficial effects: (1) the glass fiber and the modified graphene are mixed in advance and are uniformly dispersed in advance by using ethanol, so that the glass fiber and the modified graphene can be conveniently dispersed in a PA66/PC matrix, and the surface quality of an injection molding product can be improved; (2) the silane coupling agent and the epoxy resin in the formula are beneficial to compounding the filler and the matrix, so that the phenomenon of layering is avoided, and the mechanical property of the composite material is improved; (3) the addition of the graphene can endow the composite material with better heat conduction and mechanical properties.

Detailed Description

In order to make those skilled in the art fully understand the technical solutions and advantages of the present invention, the following embodiments are further described.

The raw materials used in the invention are all sold in the common market.

Example 1

The glass fiber-graphene-carbon nanotube mixed filled PA66/PC composite material is prepared from the following raw materials in parts by weight: PA 6635 parts, PC35 parts, modified graphene mixture 6 parts (the mass ratio of graphene to carbon nano tube is 5:1), glass fiber 30 parts, silane coupling agent Si5500.15 parts and epoxy resin about 0.2 part.

Firstly, uniformly mixing weighed graphene and carbon nano tubes according to a proportion, then adding the mixture into a concentrated sulfuric acid solution with the mass fraction of 82%, stirring at normal temperature for 7-14min, adding water for dilution, filtering, washing filter residues for multiple times by using a 0.1-0.3mol/L NaOH solution, then washing with water to be neutral, dispersing the filter residues in an ethanol solution with the volume fraction of 60%, then adding glass fibers, stirring, then placing in an environment with the temperature of 0-4 ℃, refrigerating for 12-18h, and freeze-drying to obtain the modified graphene-glass fiber mixture.

And then uniformly mixing the modified graphene-glass fiber mixture, the PA66/PC matrix, the silane coupling agent and the epoxy resin, and performing melt granulation by a double-screw extruder to obtain the graphene/PC/PA/PC/PA. The technological parameters are as follows: the length-diameter ratio of the double-screw extruder is 1:30-40, the rotating speed is 330rad/s, and the melting temperature is 240-.

Example 2

The glass fiber-graphene-carbon nanotube mixed filled PA66/PC composite material is prepared from the following raw materials in parts by weight: PA 6640 parts, PC30 parts, modified graphene mixture 10 parts (the mass ratio of graphene to carbon nano tube is 3:1), glass fiber 30 parts, silane coupling agent Si5500.11 parts and epoxy resin about 0.22 part.

Firstly, uniformly mixing weighed graphene and carbon nano tubes according to a proportion, then adding the mixture into a concentrated sulfuric acid solution with the mass fraction of 85%, stirring at normal temperature for 7-14min, adding water for dilution, filtering, washing filter residues for multiple times by using a 0.1-0.3mol/L NaOH solution, then washing the filter residues to be neutral by using water, dispersing the filter residues in an ethanol solution with the volume fraction of 40%, then adding glass fibers, stirring, then placing in an environment with the temperature of 0-4 ℃, refrigerating for 12-18h, and freeze-drying to obtain the modified graphene-glass fiber mixture.

The plastic part formed by injection molding of the PA66/PC composite material prepared by the invention has the advantages that no fiber floating and glass fiber leakage phenomena exist on the surface of the product immediately under high filling, the tensile strength and the heat resistance are improved to a certain degree, no layering phenomenon is found through further microscopic observation, and the product is good in public praise of customers.

Claims

1. The glass fiber-graphene-carbon nanotube mixed and filled PA66/PC composite material is characterized in that raw materials of the composite material comprise a matrix consisting of PA66 and PC, a modified graphene mixture, glass fibers, a silane coupling agent and epoxy resin, wherein the weight ratio of the matrix to the glass fibers to the modified graphene mixture is 7:3:0.6-1.2, and the use amounts of the silane coupling agent and the epoxy resin are respectively 0.1-0.2% and 0.2% of the weight of the composite material; the weight ratio of PA66 to PC in the matrix is 1:0.5-1.5, and the silane coupling agent is Si 550; the preparation method of the composite material comprises the following steps: (1) mixing graphene and carbon nanotubes according to a mass ratio of 1-5:1, adding the obtained mixture into a concentrated sulfuric acid solution with a mass fraction of 82-86%, stirring at normal temperature for 7-14min, adding water for dilution, filtering, washing filter residues with 0.1-0.3mol/L NaOH solution for multiple times, and washing with water until the filter residues are neutral, wherein the obtained filter residues are the modified graphene mixture; dispersing the modified graphene mixture in 40-60% ethanol solution by volume, adding glass fiber, stirring, refrigerating at 0-4 ℃ for 12-18h, and freeze-drying to obtain a modified graphene-glass fiber mixture; (2) uniformly mixing the modified graphene-glass fiber mixture, a PA66/PC matrix, a silane coupling agent and epoxy resin, and performing melt granulation by using a double-screw extruder, wherein the length-diameter ratio of the double-screw extruder is 1:30-40, the rotating speed is 330rad/s, and the melting temperature is 240-.