Structure control method of outer surface of polypropylene separation membrane

A technology of structure control and polypropylene, applied in semi-permeable membrane separation, chemical instruments and methods, membrane technology, etc., can solve the problems of low membrane flux and dense skin on the outer surface of the membrane, and achieve simple methods, increased porosity, The effect of eliminating the possibility of large pores

Active Publication Date: 2015-06-17
CHINA PETROLEUM & CHEM CORP +1
View PDF8 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] The technical problem solved by the present invention: the present invention provides a method for controlling the structure of the outer surface of the polypropylene separation membrane, by controlling the type and temperature of the coagulation bath, to solve the problem of using TIPS to prepare polypropylene hollow fibers in the prior art. When using a membrane, the skin on the outer surface of the membrane is dense and the membrane flux is low

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
  • Structure control method of outer surface of polypropylene separation membrane
  • Structure control method of outer surface of polypropylene separation membrane
  • Structure control method of outer surface of polypropylene separation membrane

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] A method for controlling the structure of the outer surface of a polypropylene separation membrane, the specific steps are as follows:

[0041] (1) Add polypropylene and diluent in the spinning kettle with stirring device, the mass fraction of polypropylene is 25%, the melt index is 2.7g / 10min, with soybean oil as diluent, the mass fraction of diluent is 75% %, heated to 200°C, and stirred for 0.5h under the condition of nitrogen flow, and left to defoam for 0.5h after stopping the stirring to obtain the casting solution;

[0042] (2) The casting liquid is filtered through a stainless steel filter, and the casting liquid is transported to the spinneret by a gear-type metering pump, and nitrogen is used as the inner core liquid to introduce into the spinneret to form a hollow fiber. The temperature of the spinneret is 175°C ; Extrude the hollow fiber, first pass through an air gap of 1 cm, and then enter 100% soybean oil at 20°C for cooling and solidification.

[0043] (3...

Embodiment 2

[0046] A method for controlling the structure of the outer surface of a polypropylene separation membrane, the specific steps are as follows:

[0047] (1) Add polypropylene and diluent to the spinning kettle with a stirring device, the mass fraction of polypropylene is 40%, the melt index is 8g / 10min, dilute with the mixture of soybean oil and dioctyl phthalate agent, the mass fraction of dioctyl phthalate in the mixture is 10%, the mass fraction of the diluent is 60%, heated to 175°C, and stirred for 3h under the condition of nitrogen flow, after stopping the stirring, let stand for defoaming for 2h, and obtain Casting solution;

[0048] (2) The casting solution is filtered through a stainless steel filter, and the casting solution is transported to the spinneret by a gear-type metering pump, and nitrogen is used as the inner core liquid to introduce into the spinneret to form a hollow fiber. The temperature of the spinneret is 140°C ; The hollow fiber is extruded, first pas...

Embodiment 3

[0052] A method for controlling the structure of the outer surface of a polypropylene separation membrane, the specific steps are as follows:

[0053] (1) Add polypropylene resin and diluent in the spinning kettle with stirring device, the mass fraction of polypropylene resin is 27%, and the melt index is 3g / 10min, with the mixture of soybean oil and dibutyl phthalate As a diluent, the mass fraction of dibutyl phthalate in the mixture is 90%, the mass fraction of the diluent is 73%, heat to 180°C, and stir for 1h under the condition of nitrogen flow, stop stirring and stand for defoaming for 1h , to obtain the casting solution;

[0054] (2) After the casting solution is filtered by a stainless steel filter, the casting solution is transported to the spinneret by a gear-type metering pump, and nitrogen is introduced into the spinneret as the inner core liquid to form a hollow fiber. The temperature of the spinneret is 145 °C; the hollow fiber is extruded, first passes through ...

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
melt flow indexaaaaaaaaaa
melt flow indexaaaaaaaaaa
melt flow indexaaaaaaaaaa
Login to view more

Abstract

The invention relates to a structure control method of the outer surface of a polypropylene separation membrane. The method comprises the steps that: (1) polypropylene and a diluent are added into a kettle with a stirring device; the mixture is heated and stirred, such that a membrane casting solution is prepared; (2) the membrane casting solution is filtered by using a filter; an inner core liquid is introduced into a spinning nozzle; the inner core liquid and the membrane casting solution are extruded by the spinning nozzle; the mixture is cooled and cured through 0-20 DEG C coagulation bath, such that a hollow fiber membrane is obtained; (3) the hollow fiber membrane is wound by using a winding machine, and is extracted in one or a plurality of extraction agents; and (4) the extracted membrane is fetched and dried; and the extraction agent is removed, such that the polypropylene hollow fiber separation membrane is obtained. According to the invention, variety and temperature conditions of the coagulation bath are improved, such that a problem of polypropylene separation membrane outer surface compact skin is solved. Polypropylene separation membrane porosity is improved from 44% to approximately 70%, and polypropylene separation membrane pore size is reduced from 0.45 to approximately 0.25. The increasing of porosity and the reduction of pore size show that the membrane pores are more uniform, and the probability of large pores is reduced or eliminated.

Description

technical field [0001] The invention belongs to the field of polymer material science, relates to a preparation method of a polymer separation membrane, and more particularly relates to a method for controlling the structure of the outer surface of a polyolefin separation membrane. Background technique [0002] A polymer separation membrane is a polymer interface that separates two homogeneous substances. With the development of membrane science and technology, polymer separation membranes have been widely used in water treatment, chemical industry, electronics, steel, medical treatment, food and other industries. As a polyolefin material, polypropylene is a highly crystalline thermoplastic resin polymerized mainly from propylene monomers. It has high transparency, non-toxicity, light specific gravity, easy processing, high impact strength, chemical corrosion resistance, and Flexibility, good electrical insulation and other excellent properties. Due to its excellent perfor...

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): B01D69/08B01D71/26B01D67/00
Inventor 王玉杰奚振宇杨永强赵鹏
Owner CHINA PETROLEUM & CHEM CORP
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