PDMS/PEI (Polydimethylsiloxane/Polyetherimide) separating membrane and preparation and application thereof

Abstract

The invention belongs to the field of membrane materials and discloses a PDMS / PEI (Polydimethylsiloxane / Polyetherimide) separating membrane and a preparation method of the separating membrane as well as the application of the separating membrane. The preparation method comprises the following steps of: preparing high polymer emulsion of organic silicon by adopting an emulsion polymerization method, further crosslinking into silicone rubber under the effects of a catalytic agent and a cross-linking agent, and forming the PDMS / PEI composite membrane on a basement membrane through high temperature curing. The siloxane prepared by the preparation method has high molecular weight; the prepared membrane has smooth and compact surfaces without defects and is tightly combined with PEI. The membrane prepared by the method is pollution-free and non-toxic. The prepared separating membrane is used for separating and recovering organic gases, thereby higher selectivity is obtained.

Description

technical field [0001] The invention belongs to the field of membrane materials and relates to a novel high-efficiency organic gas separation membrane and its preparation method and application, in particular to a PDMS / PEI separation membrane and its preparation method and application. Background technique [0002] A large amount of volatile organic vapors (VOCs) will be produced during the refining, storage and transportation of petroleum, which not only causes a large amount of waste of petroleum resources and huge economic losses, but also directly endangers the safety of human life and the living environment. increasingly people's attention. It is estimated that in 2005, the VOCs emissions from gas stations alone in my country reached 314×10 3 t, the resulting economic loss has reached 1.26 billion yuan, and the VOCs emissions will reach 1196×10 by 2030 under the condition of maintaining the current control level. 3 t, and the current market oil price keeps rising, ass...

AI Technical Summary

Problems solved by technology

[0004] In recent years, polydimethylsiloxane (PDMS) is the most widely used membrane material for VOCs separation in foreign laboratories. Since the permeability of VOCs gas in the PDMS membrane layer is much higher than that of inert gases, good results have been obtained. separation effect, but currently there are very few domestic manufacturers that can industrialize, and the reported preparation methods all use organic solvents to dissolve PDMS to prepare membrane solutions, causing environmental pollution and increasing costs

And because it is difficult to find a suitable solvent for PDMS materials with higher molecular weight, the molecular weight of PDMS materials generally used is lower, which causes the membrane to easily swell during use and cause membrane damage, thereby reducing its service life.