Preparation method of polycarbonate microporous material with bimodal distribution

A technology of polycarbonate and microporous materials, which is applied in the field of preparation of polycarbonate microporous materials, can solve problems such as easy pollution of the environment and single-peak distribution of thermoplastic foam, and achieve excellent dielectric properties, improved storage modulus, The effect of excellent mechanical properties

Active Publication Date: 2015-07-15
NORTHWESTERN POLYTECHNICAL UNIV
View PDF9 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] In order to overcome the deficiency that the thermoplastic foam prepared by the existing preparation method has only unimodal distribution or is easy to pollute the environment, the present invention provides a method for preparing polycarbonate microporous material with bimodal distribution

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
  • Preparation method of polycarbonate microporous material with bimodal distribution
  • Preparation method of polycarbonate microporous material with bimodal distribution
  • Preparation method of polycarbonate microporous material with bimodal distribution

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Embodiment 1: polycarbonate sheet is placed in autoclave, passes into supercritical CO 2 fluid to make polycarbonate sheets in supercritical CO 2 Carry out saturation in the fluid, the saturation pressure is 35MPa, the saturation temperature is 60°C, and the saturation time is 6h. After complete saturation, a uniform PC / CO 2 Mixture; depressurize for the first time in 20s, so that the saturation pressure in the autoclave is reduced to an intermediate pressure of 20MPa, the temperature remains constant, and the first nucleation occurs in the polycarbonate matrix and forms nuclei; After maintaining the constant temperature and pressure for 3 hours in this state, the pressure was released for the second time within 20 seconds to lower the pressure to atmospheric pressure to initiate the second nucleation; the polycarbonate sheet was quickly transferred to a constant temperature glycerin bath for nucleation Foaming, the foaming temperature is 100 ° C, and the foaming time ...

Embodiment 2

[0022]Embodiment 2: polycarbonate sheet is placed in autoclave, passes into supercritical CO 2 fluid to make polycarbonate sheets in supercritical CO 2 Saturation in the fluid, the saturation pressure is 25MPa, the saturation temperature is 25°C, and the saturation time is 3h. After complete saturation, a uniform PC / CO 2 Mixture; depressurize for the first time in 30s, so that the saturation pressure in the autoclave is reduced to an intermediate pressure of 20MPa, the temperature remains constant, and the first nucleation occurs in the polycarbonate matrix and forms nuclei; After maintaining the constant temperature and pressure in this state for 0.5h, the second pressure relief is carried out within 30s to reduce the pressure to atmospheric pressure to initiate the second nucleation; the polycarbonate sheet is quickly transferred to a constant temperature glycerin bath for Foaming, the foaming temperature is 160 ° C, and the foaming time is 5s, then the foamed material is p...

Embodiment 3

[0023] Embodiment 3: polycarbonate sheet is placed in autoclave, feeds supercritical CO 2 fluid to make polycarbonate sheets in supercritical CO 2 Carry out saturation in the fluid, the saturation pressure is 20MPa, the saturation temperature is 60°C, and the saturation time is 6h. After complete saturation, a uniform PC / CO 2 Mixture; within 10s, the pressure is relieved for the first time, so that the saturation pressure in the autoclave is reduced to an intermediate pressure of 14MPa, and the temperature is kept constant, and the first nucleation occurs in the polycarbonate matrix and forms nuclei; After maintaining constant temperature and pressure in this state for 1 hour, release the pressure for the second time within 10 seconds to reduce the pressure to atmospheric pressure to initiate the second nucleation; quickly transfer the polycarbonate sheet to a constant temperature glycerin bath for nucleation Foaming, the foaming temperature is 150 ° C, and the foaming time i...

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
pore sizeaaaaaaaaaa
pore sizeaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of a polycarbonate microporous material with bimodal distribution, aiming at solving the technical problem that the thermoplastic foam prepared by adopting the existing preparation method only has unimodal distribution or easily pollutes the environment. According to the technical scheme, the preparation method disclosed by the invention comprises the steps of: placing a polycarbonate sheet in CO2 fluid under a super-critical state to carry out saturation to obtain an even PC (polycarbonate) / CO2 mixture after being entirely saturated; carrying out first-time fast pressure relief within the time of 4-30 seconds, and keeping for 0.5-3 hours under the constant-temperature and constant-pressure state; carrying out second-time fast pressure relief within the time of 4-30 seconds, thus relieving the pressure in an autoclave to the atmospheric pressure; fast taking out the CO2 gas-containing polycarbonate sheet, transferring to a constant-temperature glycerol bath to carry out foaming; and finally, shaping the foamed polycarbonate sheet in an ice-water bath for 30 minutes to obtain the polycarbonate microporous material with bimodal distribution. The supercritical CO2 fluid used in the preparation method is low-cost, non-toxic and non-inflammable, and has no pollution to the atmosphere and water body, as well as no damage role to ozone sphere, thus being an environment-friendly physical foaming agent.

Description

technical field [0001] The invention relates to a preparation method of polycarbonate microporous material, in particular to a preparation method of polycarbonate microporous material with bimodal distribution. Background technique [0002] Compared with traditional foam plastics, polymer microporous materials have excellent properties such as high specific strength, high impact strength, long fatigue life, good thermal stability, low thermal conductivity and low dielectric constant, and are widely used in aerospace, microelectronics, and automobile industries. , insulation materials and many other high-tech fields have extremely important application value. [0003] The preparation of microporous materials is mainly divided into physical foaming method and chemical foaming method. with supercritical CO 2 The physical foaming method in which the fluid is a blowing agent is superior to the chemical foaming method because of its controllability in operation and environmental...

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): B29C67/20B29K69/00
Inventor 张广成马忠雷杨全史学涛
Owner NORTHWESTERN POLYTECHNICAL UNIV
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