Study On The Polymer-inorganic Compound System Under High Pressure

Polymer-based organic/inorganic nanocomposite is supposed to improve the performance of polymer by filling it with inorganic material, making polymer's application field broader. When polymer is filled in with the inorganic part in the criterion of nanometer, it takes only a small percentage (<10%, <5% in most circumstances)to improve the polymer's performance greatly, such as mechanical strength, thermal stability, gas barrier property, and it can even be the electrical and Magnetic characteristics.Polymer/Layered Silicate nanocomposite is a new type of organic-inorganic nanocomposite which prepared by exfoliating layered silicate into Nano-layers and dispersing in the polymer matrix. Graphite, which has the same crude nanometer sheet structure, is a hot choice to compound in the field of function material, too.Intercalation method is the main method which is used to prepare Polymer/Layered Silicate nanocomposites. Different from the traditional method, using domestic cubic hinge press, under several GPa press, rectorite(without surface modification)/phenolic resin nanocomposite is prepared ,at the same time ,we start to study the performance of graphite phenolic resin nanocomposite under high Pressure. High pressure method was used to produce phenolic resin (PF)/rectorite (REC) nanocomposites (REC contents 9wt%) under the pressure from 2GPa to 4GPa . The structure and performance of the material phase was studied by X-ray diffraction(XRD),transmission electron microscope(TEM),and thermal analysis. XRD test shows that, the diffraction peak intensity about crystal face(OOl) and crystal face(002) was singnificantly decreased after high-pressured processing. Exfoliated rectorite Nano-layers can be Clear observed by TEM, and TGA shows that the nanocomposite's thermal decomposition concentrates in the temperature sector of 497.8℃-510.9℃. The experimental results show that ,without interlayer polymerization, exfoliated PF/Clay nanocomposites can be formed by intercalating polymeric molecules into the interlayer space of clay.Contrasting with the F-2 graphite ,The structure and the material phase of the expanded graphite/phenolic resin nanocomposite which dealing with 2GPa～4GPa high Pressure(contain Expanded Graphite 20wt%), was studied by X-ray diffraction(XRD), transmission electron microscope (TEM). We direct current two point probe method to measure the difference of its resistance, and use three-point bending to test the difference of its flexural strength before and after the procedure of high pressure. The experimental results show that, after oxidation and expansion, the diffraction peak intensity of graphite's (002)crystal face weaken, and Nano graphite layers can be observed by TEM. From atmosphere to 4GPa high Pressure, Resistivity of EG/PF nanocomposite rises From 0.4MΩ·cm to 33MΩ·cm,flexural strength of EG/PF nanocomposite rises From 24.9MPa to 51.4MPa.But flexural strength of F-2/PF nanocomposite (contain Expanded Graphite 20wt%) rises only from 15.4MPa to 20.2MPa.