Preparation And Property Of Mesoscopic Lamellar Vermiculite/Heat Resistant Polymer Composite Membrane

Polymer/lamellar vermiculite composite material can dramatically enhance the thermodynamics and mechanical properties of the polymer.To prepare high performance composite material with simple process is expected to become a new method.At present,studies on uniform mixing of polymer material and nano inorganic particles such as montmorillonite, silicon dioxide et al,as well as the properties of the polymer/organic compound composite membranes have attracted much scientific and industrial attention.However,the report on polymer/lamellar vermiculite composite material has not been found yet.Vermiculite,a type of clay minerals,will have a dramatic expansion when subjected to high temperature roasting and obtains excellent fire resistant and heat insulation properties.Polyaromaticethersulfone with cardo group(PES-C) and poly phthalazinone ether ketone sulfon(PPESK) are both heat-resistant polymers with high-grade heat-resistant property,good dimensional stability and easy processing property etc.It has very important significance to optimize the performance of heat-resistant polymer by uniform mixing mesoscopic lamellar vermiculite and heat-resistant polymer and preparing polymer/lamellar vermiculite composite membrane through L-S phase inversion technique.In this paper,firstly,the organic vermiculite and exfoliated vermiculite are prepared.Then vermiculite after first sand milling or organic vermiculite or exfoliated vermiculite and PES-C or PPESK are mixed using ultrasonic disruption.Finally,the lamellar vermiculite/heat-resistant polymer composite membranes are obtained through L-S phase inversion technique.The thermal stabilities,thermal isolating properties and mechanical properties of the composite membranes are studied.The main results obtained are as follows:Organic vermiculites intercalated with different kinds of organic quaternary ammonium salts are obtained through cation exchange in water.X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR) and thermogravimetric analyses(TGA) are used to characterize the effect of intercalation.The organic vermiculite intercalated with C 12,C 16,C22,Cdl8 were then treated by sand milling with dispersant and ultra-high pressure homogenizer for 5 times,and then characterized by XRD,FTIR,TGA and X-ray fluorescence analysis.Experimental results showed that the organic vermiculite with larger basal spacing can be exfoliated after sand milling and ultra-high pressure homogenizer treatment.Lamellar vermiculite/heat-resistant polymer composite membranes are obtained using L-S phase inversion technique.The thermal stabilities,thermal isolating properties and mechanical properties of the composite membranes are studied and compared.The results showed that adding with certain amount of lamellar vermiculite can enhance the thermal stabilities and mechanical properties of the polymer which,however,would be undermined if too much lamellar vermiculite were added.Adding certain amount of lamellar vermiculite can enhance the thermal isolating properties of the composite effectively,after that, with the increasing amount of lamellar vermiculite,the thermal isolating properties of the composite membranes can not be enhanced effectively.