CN-122011756-A - Polyamide composition and preparation method and application thereof

Abstract

The invention relates to a polyamide composition, a preparation method and application thereof. The polyamide composition comprises polyamide resin, biotite, MCA flame retardant and carbon black. The polyamide composition disclosed by the invention has good flame retardant property, is a material with high blackness, has high whiteness of a laser marking area and high contrast of the laser marking area and an unlabeled area, and is very suitable for preparing parts which have requirements on flame retardant property and blackness and need to form marks through laser marking and have a safety key marking effect through the marks, such as an electric appliance shell.

Inventors

• YI XIN
• DING CHAO
• YE NANBIAO
• WU CHANGBO
• OUYANG QI
• LI XIANGQIAN

Assignees

• 上海金发科技发展有限公司
• 江苏金发科技新材料有限公司

Dates

Publication Date

20260512

Application Date

20260122

Claims (10)

1. 1. The polyamide composition is characterized by comprising the following components in parts by weight: 69-90 parts of polyamide resin, 1.8-5 Parts of biotite, 6-10 Parts of MCA flame retardant, 0.05 To 0.15 part of carbon black, The average particle size of the MCA flame retardant is 5-10 mu m, and the average particle size of the carbon black is 5-40 nm.
2. 2. The polyamide composition of claim 1, wherein the polyamide resin is at least one of PA66, PA6, PA56, PA12, PA610, or PA 1012.
3. 3. The polyamide composition according to claim 1, wherein the polyamide resin has a relative viscosity of 2.0 to 4.0.
4. 4. The polyamide composition according to claim 1, wherein the biotite has a mesh number of 1200 to 3500.
5. 5. The polyamide composition according to claim 1, wherein the mass percentage of biotite in the polyamide composition is 1.5% -6.3%.
6. 6. The polyamide composition according to claim 1, further comprising 0-2 parts of other auxiliary agents, preferably at least one of antioxidants, lubricants or nucleating agents.
7. 7. The method for preparing the polyamide composition according to any one of claims 1 to 6, which is characterized by comprising the steps of mixing the components, melt-extruding, and granulating to obtain the polyamide composition.
8. 8. Use of the polyamide composition according to any one of claims 1 to 6 for the preparation of connectors, coil formers, electrical appliance housings or switches.
9. 9. A polyamide article, characterized by being produced from the polyamide composition of any one of claims 1 to 6.
10. 10. The polyamide article of claim 9 comprising non-laser marked areas and laser marked areas, wherein the non-laser marked areas have an L value of no greater than 27 and the laser marked areas have an L value of no greater than 61.

Description

Polyamide composition and preparation method and application thereof Technical Field The invention relates to the technical field of high polymer materials, in particular to a polyamide composition, a preparation method and application thereof. Background The polyamide resin has excellent mechanical property, barrier property, heat resistance, wear resistance, chemical corrosion resistance and the like, and the composite material thereof is widely applied to the fields of machinery manufacturing industry, household appliances, electric tools, electronic appliances, transportation and the like. Melamine Cyanurate (MCA) has high nitrogen content, generates non-combustible gases such as NH 3、H2O、N2、CO2、H2 NCN and the like when being heated and decomposed, has the functions of absorbing heat, reducing temperature and diluting the concentration of the combustible gases and oxygen, and is commonly used as a flame retardant modifier of thermoplastic resin. Meanwhile, the MCA has a wide source, and has higher cost performance compared with the traditional bromine-antimony flame retardant material and organic phosphorus flame retardant material, so the MCA has wide application in the fields of low-voltage appliances, electronic and electric appliances and household appliances. The polyamide material generally shows matte finish due to crystallization property and easy water absorption property, and after the MCA is further added, the MCA is white substance, so that the flame-retardant nylon product with high blackness is very difficult to realize. On the other hand, such products may also have laser marking requirements (e.g., electrical appliance housings) that require the marking location to be white. However, the prior art is difficult to realize flame retardance, high blackness and laser marking at the same time, the addition of MCA is not beneficial to improving the blackness of the material, and in order to improve the blackness of the material, the dosage of carbon black is usually increased, but too much dosage of carbon black brings obvious negative effects to the laser marking of the material, and the marking is particularly characterized in that the marking of infrared laser marking is yellow and deep, and is carbonized and blackened when serious, so that white marks are difficult to form, and the marking effect is poor. Moreover, the white mark is formed only to meet the requirement of general readability, and with the improvement of safety standard standards and the like, the black shell and the white mark are required to form high contrast (namely, the difference between the L value of the marked area and the L value of the unmarked area is large) so as to meet the requirement of safety key marks (such as warning), and the laser marking is realized only by carbon black, so that even if the white mark is formed, the requirement of high contrast is still difficult to meet, and the effect of the safety key marks cannot be achieved. At present, three effects of high blackness of the MCA flame-retardant polyamide material, easiness in forming white marks by laser marking and high contrast between marked areas and unmarked areas are not reported in the industry. Disclosure of Invention The primary object of the present invention is to overcome the problems or disadvantages of the prior art and to provide a polyamide composition. It is a further object of the present invention to provide a process for the preparation of the above polyamide composition. It is a further object of the present invention to provide the use of the polyamide composition described above for the preparation of automotive parts. The above object of the present invention is achieved by the following technical solutions: a polyamide composition comprises the following components in parts by weight: 69-90 parts of polyamide resin, 1.8-5 Parts of biotite, 6-10 Parts of MCA flame retardant (melamine cyanurate), 0.05 To 0.15 part of carbon black, The average particle size of the MCA flame retardant is 5-10 mu m, and the average particle size of the carbon black is 5-40 nm. The inventor of the invention regulates and controls the dosage of the carbon black within a certain range in order to avoid the problems of obvious yellowing, deep and even carbonization of marks during laser marking of the polyamide composition. However, the amount of carbon black in the range is insufficient to allow the polyamide composition itself to be visibly black. The inventor of the invention researches and discovers that a certain amount of biotite is added and the average particle size of carbon black is regulated within a certain range, so that the polyamide composition can reach enough blackness, the whiteness of the area of the polyamide composition after laser marking is high, and the contrast ratio of the marked area and the unmarked area can be improved. In the formula system of the polyamide composition, the light absorption effect of the carbon black is