Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A method of processing ultra-high molecular weight polyethylene by spark plasma sintering

A spark plasma, ultra-high molecular weight technology, applied in the field of material processing, can solve the problems of limited chain motion, low crystallinity, difficult chain lamellae, etc., and achieve the effects of improving motion activity, improving wear performance, and reducing melting defects

Active Publication Date: 2022-03-25
SOUTH CHINA UNIV OF TECH
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the entanglement density of random coils increases in the molten state, the free volume of molecular chains decreases under high pressure, the movement of the chains is restricted, and it is difficult to recrystallize and grow folded chain lamellae, resulting in interfacial melting defects, low crystallinity, oxidative degradation, poor mechanical properties

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
  • A method of processing ultra-high molecular weight polyethylene by spark plasma sintering
  • A method of processing ultra-high molecular weight polyethylene by spark plasma sintering
  • A method of processing ultra-high molecular weight polyethylene by spark plasma sintering

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] The powdered ultra-high molecular weight polyethylene was placed in an oven at 60° C. for 4 hours, and 0.847 g of ultra-high molecular weight polyethylene was filled and cold-pressed in a graphite mold with a pressure of 10 MPa. Then spark plasma sintering was performed in a vacuum (7Pa) atmosphere with a pulse time of 10 ms and an on-off ratio of 5:1. The initial sintering pressure was 10MPa, the initial sintering temperature was room temperature, the temperature was raised to 100°C at a rate of 25°C / min, and the temperature was maintained for 2 minutes; The sintering temperature was raised from 100 °C to 200 °C; then, the temperature was maintained for 1 min; finally, the pressure was maintained at 30 MPa, water cooled to 100 °C with the furnace, and then cooled to room temperature naturally, the mold was taken out, and the mold was disassembled to obtain UHMWPE-1.

[0030] The characterization of the obtained sample 1 is shown in Figure 2 and image 3 , where Figure...

Embodiment 2

[0032] The powdered ultra-high molecular weight polyethylene was placed in an oven at 50° C. for 5 hours, and 0.984 g of ultra-high molecular weight polyethylene was taken and filled in a graphite mold for cold pressing, and the pressure was 20 MPa. Sintering was then carried out in a vacuum (10Pa) atmosphere with a pulse time of 15 ms and an on-off ratio of 10:1. The initial sintering pressure was 10MPa, the initial sintering temperature was room temperature, the temperature was raised to 100°C at a rate of 25°C / min, and the pressure was maintained for 2 minutes; The sintering temperature was raised from 100°C to 150°C; then, the temperature was maintained for 2 minutes; finally, the pressure was maintained at 50MPa, water-cooled to 120°C with the furnace, then cooled to room temperature naturally, and the mold was taken out to obtain UHMWPE-2. The SEM of the surface of the obtained sample 2 after the friction and wear test is shown in Figure 4 , showing that there are no p...

Embodiment 3

[0034] The powdered ultra-high molecular weight polyethylene was placed in an oven at 70° C. for 3 hours, and 1.052 g of ultra-high molecular weight polyethylene was taken and filled in a graphite mold for cold pressing at a pressure of 5 MPa. Sintering was carried out in a vacuum (4Pa) atmosphere with a pulse time of 3 ms and an on-off ratio of 3:1. The initial sintering pressure was 10MPa, the initial sintering temperature was room temperature, the temperature was raised to 100°C at a rate of 25°C / min, and the pressure was maintained for 2 minutes; then, the sintering pressure was maintained at 10MPa, and the sintering was carried out at a speed of 100°C / min. The temperature was raised from 100°C to 300°C; finally, the pressure was kept at 50 MPa, water cooled to 90°C with the furnace, and then cooled to room temperature naturally, and the mold was taken out to obtain UHMWPE-3. The infrared spectrum of the obtained sample 3 is shown in Figure 5 , not seen 900cm -1 (-CH=CH...

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
heat deflection temperatureaaaaaaaaaa
melting pointaaaaaaaaaa
compressive modulusaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for processing ultra-high molecular weight polyethylene blocks by using spark plasma sintering technology. The method includes the following steps: (1) After drying the UHMWPE powder, it is prepared into a blank by cold pressing as a pre-sintered body; (2) The pre-sintered body is sintered and shaped by spark plasma sintering. The surface of the powder is melted by heating and sintered under a certain pressure to improve the movement activity of the macromolecular chain in the melt on the powder surface, accelerate the diffusion and fusion of the molecular chain between adjacent powders, and retain the primary ecological structure inside the powder, thereby Realize low-temperature, rapid, uniform densification and consolidation of UHMWPE powder, reduce melting defects in the product, and improve its wear performance. The invention helps to solve the problems of high viscosity and poor processability of UHMWPE melt, and expands the application of the spark plasma sintering method in the high-efficiency and low-cost preparation of high-performance and difficult-to-process polymer materials.

Description

technical field [0001] The invention belongs to the field of material processing, and in particular relates to a method for processing ultra-high molecular weight polyethylene by using spark plasma sintering. Background technique [0002] Ultrahigh molecular weight polyethylene (UHMWPE) is a linear polyethylene with a molecular weight of more than 1.5 million. Molecular formula: –(–CH 2 –CH 2 –) n –, Density: 0.920~0.940g / cm 3 . Heat distortion temperature (0.46MPa): 85℃, melting point: 130~136℃, with ultra-long, linear, flexible, non-polar molecular chain structure. On the one hand, this structure endows it with excellent performance beyond other engineering plastics, and has broad application prospects in extremely special environments; its promotion and application. Therefore, studying the molding processing of UHMWPE has always been one of the problems that the polymer academia and industry are concerned about. [0003] At present, UHMWPE is mainly formed and pro...

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
Patent Type & Authority Patents(China)
IPC IPC(8): B29C67/04B29B13/06B29C33/38
CPCB29C67/04B29B13/065B29C33/38
Inventor 方立明潘西满祁海生储康杰任富增王勇强
Owner SOUTH CHINA UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com