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CN-115989272-B - Polyamide composition with slope leakage tracking resistance

CN115989272BCN 115989272 BCN115989272 BCN 115989272BCN-115989272-B

Abstract

The present invention relates to a method for improving the slope tracking (IPT) performance at voltages above 1kV by using a polyamide composition. The polyamide composition comprises a) 10-50 wt.% of at least one semi-crystalline aliphatic polyamide, each amide group having on average 3-5 carbon atoms, excluding carbon atoms in the carbonyl group, b) 1-40 wt.% of at least one long chain aliphatic polyamide, each amide group having on average equal to or more than 6 carbon atoms, excluding carbon atoms in the carbonyl group, c) 0-35 wt.% of a flame retardant, d) 0-50 wt.% of a fibrous and/or particulate filler, e) 1-25 wt.% of an impact modifier, and f) 0-20 wt.% of other additives.

Inventors

  • YAN DONG
  • Dou rui
  • DENG JIAYAN

Assignees

  • 巴斯夫欧洲公司

Dates

Publication Date
20260505
Application Date
20210816
Priority Date
20200828

Claims (20)

  1. 1. A method of improving the tracking performance of a bevel electrical leakage at a voltage greater than 1 kV by using a polyamide composition comprising: a) 10-50% by weight of at least one semi-crystalline aliphatic polyamide, each amide group having an average of 3-5 carbon atoms, excluding the carbon atoms in the carbonyl group; b) 1 to 40% by weight of at least one long-chain aliphatic polyamide, each amide group having on average equal to or more than 6 carbon atoms, excluding the carbon atoms in the carbonyl group; c) 0-35 wt% of a flame retardant; d) 0-50% by weight of fibrous and/or particulate filler; e) 1 to 25% by weight of an impact modifier, and F) 0-20% by weight of other additives.
  2. 2. The method of claim 1, wherein the semi-crystalline aliphatic polyamide is selected from polyamide 4, polyamide 6, polyamide 56, polyamide 46, polyamide 66, and/or polyamide 6/66.
  3. 3. The method of claim 2, wherein the semi-crystalline aliphatic polyamide is polyamide 66.
  4. 4. The process according to claim 1 or 2, wherein the amount of component a) is from 15 to 45% by weight, based on the total weight of the polyamide composition.
  5. 5. The process according to claim 1 or 2, wherein the amount of component a) is from 20 to 40% by weight, based on the total weight of the polyamide composition.
  6. 6. The method of claim 1 or 2, wherein the at least one long chain aliphatic polyamide is selected from the group consisting of polyamide 1212, polyamide 610, polyamide 612, polyamide 1010, and polyamide 6/6.36.
  7. 7. The process according to claim 1 or 2, wherein the amount of component b) is from 5 to 30% by weight, based on the total weight of the polyamide composition.
  8. 8. The process according to claim 1 or 2, wherein the amount of component b) is from 8 to 25% by weight, based on the total weight of the polyamide composition.
  9. 9. The process according to claim 1 or 2, wherein the amount of component b) is from 10 to 25% by weight, based on the total weight of the polyamide composition.
  10. 10. The method of claim 1 or 2, wherein the flame retardant comprises (c 1) 3-15 weight percent red phosphorus and (c 2) 1-10 weight percent triazine flame retardant, based on the total weight of the polyamide composition.
  11. 11. The method of claim 10, wherein the triazine flame retardant is selected from melamine phosphate, bis-melamine phosphate, melamine pyrophosphate, bis-melamine pyrophosphate, dimethyl oxazine phosphate, or melamine polyphosphate.
  12. 12. The process according to claim 1 or 2, wherein the amount of flame retardant c) is from 4 to 25 wt.%, based on the total weight of the polyamide composition.
  13. 13. The process according to claim 1 or 2, wherein the amount of flame retardant c) is from 8 to 18 wt.%, based on the total weight of the polyamide composition.
  14. 14. The method of claim 1 or 2, wherein the fibers are glass fibers.
  15. 15. The method of claim 1 or 2, wherein the fibers are alkali-free E-glass fibers.
  16. 16. The method of claim 1 or 2, wherein the impact modifier is selected from maleic anhydride functionalized polyolefin, glycidyl methacrylate functionalized ethylene terpolymer, or a combination thereof.
  17. 17. The method of claim 16, wherein the maleic anhydride functionalized polyolefin is selected from maleic anhydride functionalized polyethylene copolymers.
  18. 18. The process according to claim 1 or 2, wherein the weight ratio of components a) and b) in the polyamide composition is from 5:1 to 1:1.
  19. 19. The process according to claim 1 or 2, wherein the weight ratio of polyamide components a) and b) in the polyamide composition is from 4:1 to 1:1.
  20. 20. The process according to claim 1 or 2, wherein the weight ratio of polyamide components a) and b) in the polyamide composition is from 3.5:1 to 2.5:1.

Description

Polyamide composition with slope leakage tracking resistance Technical Field The present invention relates to a method for improving the slope tracking (IPT) performance at voltages above 1kV by using a polyamide composition. The polyamide composition comprises a) 10-50 wt.% of at least one semi-crystalline aliphatic polyamide, each amide group having on average 3-5 carbon atoms, excluding carbon atoms in the carbonyl group, b) 1-40 wt.% of at least one long chain aliphatic polyamide, each amide group having on average equal to or more than 6 carbon atoms, excluding carbon atoms in the carbonyl group, c) 0-35 wt.% of a flame retardant, d) 0-50 wt.% of a fibrous and/or particulate filler, e) 1-25 wt.% of an impact modifier, and f) 0-20 wt.% of other additives. The invention also relates to polyamide compositions and articles produced therefrom. Background After the epoxy resin is introduced in the 50 th century of 20 th year, the polymer material is widely used as a high-voltage insulating material. Initially, the polymers were used in indoor environments. The rosentaer company introduced in 1976 a composite insulator made of silica gel. The polymer insulators may be complex in shape and their components may be thinner than ceramic insulators. Unfortunately, polymers are many times less resistant to surface discharge than ceramic materials. For this reason, several methods have been proposed to improve the polymer's resistance to high pressure degradation. Polyamide 66 (PA 66) is a very important engineering thermoplastic polymer because it combines several desirable properties such as high strength and rigidity, high toughness, high heat resistance, excellent abrasion resistance, good electrical and chemical resistance, high flowability and excellent processability. PA 66 is widely used as an insulating material in the fields of automobiles, electricity and electronics. According to IEC 60112, the relative tracking index (CTI) is the most common test to evaluate the susceptibility of plastics to surface tracking, providing an indicator of the performance of insulating materials. CTI is an accelerated test method under humid and contaminated conditions, which applies a voltage between two electrodes placed on the surface of a material. Slope tracking (IPT) is an effective method for evaluating corrosion resistance and tracking resistance caused by discharge effect of insulating materials under humid conditions under high voltage effect (> 1 kV). Polymers are organic materials composed of molecules that are not as tightly bound as molecules in inorganic materials such as ceramics and glass. They can degrade at much lower temperatures than ceramics. The carbon formed during degradation renders the surface conductive and causes electrical failure, and is no longer able to withstand the applied voltage. The formation of carbon conductive paths on the surface is known as tracking. The most common polymeric materials for high pressure applications are silicone rubber, EPR rubber, cycloaliphatic epoxy resins, polycarbonates, as they have excellent properties in terms of tracking and corrosiveness, hydrophobicity, uv stability, etc. Factors such as the type of organic filler, filler size, filler conductivity, carbon content of the base polymer, etc., all affect the IPT value. Normally, the voltage test range of IPT is not higher than 1kV. CN 102732002a discloses a glass fiber reinforced PA66/PA 11 alloy with a high CTI value. The CTI value is increased by a combination of iron-removing red phosphorus, an anti-migration agent and a high CTI value reagent. However, this patent application does not disclose the definition of a high CTI value reagent. CN 102105119a discloses the use of PA 1010 and polypropylene resins to improve the toughness and flexibility of PA 66. CN 103224703a discloses that styrene-acrylonitrile can improve the toughness of polyamide composites comprising PA 66 and PA 1212. The combination of such polyamides is mainly to improve toughness, irrespective of the tracking resistance of the polyamide resin. The photovoltaic ("PV") market is moving from a 1kVA grid to a 1.5kVA grid, and this transition has led to new regulations for photovoltaic connectors and junction boxes. In the field of engineering plastics there are many products for photovoltaic applications, however, there has been little attention previously paid to high voltage applications, in particular 1.2kV, 1.5kV or 2kV applications. Polyamides with low carbon number dicarboxylic acids or lactams, such as PA 6 and PA 66, are widely used in the photovoltaic market due to their good mechanical and processing properties. However, such polyamides do not meet the requirements of photovoltaic applications with voltages higher than 1.5 kV. Disclosure of Invention It is an object of the present invention to provide a method for improving the tracking performance of a bevel electrical under a voltage higher than 1kV by using a long-chain aliphatic