Research Of Carbon Nanotube Modified Polyformaldehyde

Polyoxymethylene (POM) is a kind of high crystalline linear chain thermoplasticpolymer. Its regular conformation causes POM to structured highly and to get highcrystallinity (60~80%) and large spherical crystals in the cooling process. POM iswidely used in electronics, mechanical automoations and the car instrumentations, etc,because that it owned of wear-resistance, self-lubricating and excellent mechanicalproperties. But there are also some problems, such as low notched impact strength,toughness, and easy to decomposition, and so on, these will be greatly limited with theapplication of the POM. At present thermoplastic polyurethane elastomer (TPU) isprimarily used to modify POM. POM modified by adding TPU has wear performanceand lower rigid. Therefore, in this thesis, we added three kinds of modifiers,carbonnano tube (CNT_S)、 thermoplastic polyurethane elastomer (TPU)、 copolymerizationnylon (COPA) to POM to resolve these problems.Small amount of modifiers were added into POM. The influence of content ofmodifiers on the crystallization behavior and properties of POM were studied bymeans of differential scanning calorimeter (DSC)、polarized light microscopy (PLM)、mechanical properties test and scanning electron microscope(SEM). The resultsshowed that modifiers did not change the nucleating way of POM inPOM/TPU/COPA/CNT_S blends. With the increase of modifiers content, modifierspenetrated in the spherulites of POM and the spherulites became larger. At the sametime, three kinds of modifiers play good toughening effect in POM.When the contentof TPU was4%, COPA was4%, CNT_S was0.3%, the blending materials mechanicsperformance is the best. The impact strength and elongation at break were more thanpure POM about111%and4.5%.