Polymer Hollow Nano-sphere Modified Silicone Rubber Membrane And Its Application In Gas Separation

Gas separation can separate and purify gas mixtures.The separation methods are various.Gas membranes separation is an important branch of membrane separation technology.In many fields,the transformations from the laboratory to the large-scale industrial production have been completed.As a new separation technology,separation by membrane is energy efficient and environmentally friendly.The polymer hollow nanoparticle is a type of microsphere materials with cavities and special topologies.Due to its low density,large specific surface area and good light scattering properties,the polymer hollow nanoparticle has many superior properties and becomes a common transportation carrier.In order to overcome the trade-off effect in gas separation of the polymer membrane material in gas separation,the polymer was prepared into the hollow nanoparticle with a dense shell and filled into the polymer matrix to prepare the polymer/polymer hollow nanoparticle mixed matrix membrane,which can reduce the mass transfer path of the gas in the membrane,and then reduce the mass transfer resistance,the gas permeation and separation performance were improved.Firstly,the polyamide hollow nanoparticles were prepared in the surfactant-free microemulsion by using m-phenylenediamine and trimesoyl chloride as the aqueous phase and oil phase reaction monomer,and then blended into silicone rubber(PDMS sylgard 184).The PDMS/polyamide hollow nanoparticle mixed matrix membrane was prepared,and the effect of the intracavity cavity on the permeation and separation performance of gas was investigated.The results showed that the prepared polyamide hollow nanoparticles have a diameter of about 50 nm with a shell thickness of 10 nm.Compared with the pure PDMS membrane,the permeation and separation performance of the PDMS/polyamide hollow nanoparticle mixed matrix membrane reduced as the increase of the polyamide hollow nanoparticles loading,and aggregation of nanoparticles was observed is the mixed matrix membrane.Then,using silicone rubber as raw material,PDMS hollow nanoparticles were prepared in the surfactant-free microemulsion and blended with polyethylene oxide(PEO)to prepare the PEO/PDMS hollow nanoparticle mixed matrix membrane.The effect of the cavity structure on the permeation and separation performance of gas was investigated.The results showed that the prepared PDMS hollow nanoparticles have a diameter of about 60 nm with a shell thickness of 10 nm.The gas permeability of PEO/PDMS hollow nanoparticle mixed matrix membranes obvious improved as the increase of the PDMS hollow nanoparticles loading.When the loading of the PDMS hollow nanoparticles is 34 wt.%,the PEO/PDMS hollow nanoparticle mixed matrix membrane has the highest O2 permeability coefficient(10200 Barrer)and O2/N2 permselectivity(3.33).Compared with the pure membrane of PDMS,the O2 permeability coefficient increased by 12.35 times and the CO2 permeability coefficient increased by 10.17 times and the separation coefficient is also improved of the PEO/PDMS-34%mixed matrix membrane,exceeded the 2008 Robeson upper bound.At this loading,the CO2 permeability coefficient(35300 Barrer)and the CO2/N2 permselectivity(11.53)also exceeded the bound.