Filled modified teflon seal material and its preparation method

A polytetrafluoroethylene and sealing material technology, applied in the field of polymer sealing material modification, can solve the problem that the sealing material effect is not very ideal, etc.

Inactive Publication Date: 2012-08-08
LANZHOU UNIVERSITY OF TECHNOLOGY
View PDF4 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Currently used more fillers are glass fiber (GF), carbon fiber (CF), Al 2 o 3 , BaSO 4 , SiO 2 , SiC, potassium titanate whiskers, etc. Filling modified materials can improve some properties, but the effect as a sealing material is still not very ideal

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Filled modified teflon seal material and its preparation method

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0016] A preparation method for filling a modified polytetrafluoroethylene sealing material, the steps of which are:

[0017] (1) Mixing: Nano-Fe with oleic acid surface modified 3 o 4 Mix with the pretreated polytetrafluoroethylene powder by the above-mentioned mass percentage;

[0018] (2) Molding: Put the uniformly mixed raw materials in a compression mold and press molding, the molding pressure is 50-60MPa, the pressurization speed is 5-10MPa / min, and the pressure is maintained for 15-30min;

[0019] (3) Sintering: heat preservation at 28-30°C for 24 hours, heat up to 300-320°C at a rate of 60-100°C / hour for 0.5-1 hour, and continue to heat up to 370-390°C for 1 hour;

[0020] (4) Cooling: Cool in the furnace to 300-320°C and keep warm for 0.5-1 hour, then cool to room temperature, and store at constant temperature after simple processing and inspection of appearance and size.

[0021] The polytetrafluoroethylene powder in the present invention is a suspended polytetraf...

Embodiment 1

[0025] By mass percentage, get 95% polytetrafluoroethylene and 5% oleic acid surface modification nano-Fe 3 o 4 Add to the powder horizontal mixer and stir twice at high speed, each time for 10 minutes; place the uniformly mixed raw materials in the compression mold for molding, the molding pressure is 50MPa, the pressurization speed is 5MPa / min, and the pressure is kept for 15 minutes; keep warm at 28°C For 24 hours, heat up to 320°C at a rate of 100°C / hour for 1 hour, then continue to heat up to 370°C for 1 hour; cool to 320°C with the furnace and hold for 0.5 hours, then cool to room temperature, after simple processing and inspection of appearance dimensions Test material properties.

Embodiment 2

[0031] By mass percentage, get 92% polytetrafluoroethylene and 8% oleic acid surface modification nano-Fe 3 o 4 Add to the powder horizontal mixer and stir at high speed for 2 times, each time for 10 minutes; place the uniformly mixed raw materials in the compression mold for molding, the molding pressure is 55MPa, the pressurization speed is 10MPa / min, and the pressure is kept for 10 minutes; keep warm at 28°C For 24 hours, heat up to 300°C at a rate of 60°C / hour for 0.5 hours and then continue to heat up to 390°C for 1 hour; cool to 300°C with the furnace and hold for 1 hour to obtain a sealing material. The hardness of the material is 23.05, the tensile strength is 18.7MPa, the elongation at break is 286%, and the coefficient of linear expansion is 112.310 -6 .℃ -1 .

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Tensile strengthaaaaaaaaaa
Linear expansion coefficientaaaaaaaaaa
Tensile strengthaaaaaaaaaa
Login to view more

Abstract

Disclosed are a filled modified teflon seal material and its preparation method. The filled modified teflon seal material comprises the following components of: by weight, 5-15% of nanometer Fe3O4 with its surface modified by oleic acid and 95-85% of a teflon powder. The preparation method comprises the following steps of: firstly mixing the nanometer Fe3O4 with its surface modified by oleic acid and the pretreated teflon powder according to the above mass percent; placing the uniformly mixed raw materials into a pressing die for compression molding while the molding pressure is 50-60MPa, the pressurization speed is 5-10MPa / min and pressure maintaining lasts for 15-30min; insulating at the temperature of 28-30 DEG C for 24 hours, heating to 300-320 DEG C at the heating rate of 60-100 DEG C / h, insulating for 0.5-1 hour, continuously heating to 370-390 DEG C, insulating for 1 hour; cooling to 300-320 DEG C in a furnace, insulating for 0.5-1 hour, cooling to room temperature, followed by simple processing and outside dimension detection, and preserving at constant temperature.

Description

technical field [0001] The invention relates to the technology of polymer sealing material modification. Background technique [0002] Polytetrafluoroethylene is a perfluorinated polymer obtained by free radical polymerization of monomer tetrafluoroethylene. Due to its special structural characteristics, it has high chemical stability, strong high and low temperature resistance, and outstanding Non-viscous, good lubricity, excellent electrical insulation, aging resistance, minimal water absorption, etc., making it very suitable for the manufacture of seals that require high corrosion resistance and a wide temperature range, such as heat exchangers, Seals for high-pressure vessels, grooved flanges, shafts, piston rods, valve stems, packings for worm gear pumps, etc. However, due to its poor mechanical properties, large linear expansion coefficient, poor creep resistance, poor wear resistance, low hardness, and difficulties in forming and secondary processing, its application...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C08L27/18C08K9/04C08K3/22B29C67/04B29C43/00
Inventor 何世权饶文武苏清苗郑耀龙郭俊德景然
Owner LANZHOU UNIVERSITY OF TECHNOLOGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products