Study On Preparation And Properties Of Polyamide6/Modified Carbon Black Nanocomposite Materials By In-Situ Polymerization

Polyamide is the most thermoplastic polyamide application engineering plastics.It is many groups with the structure of the unit were connected to a long chain ofpolymer compound. PA6has good comprehensive performance, including mechanicalproperties, heat resistance, wear resistance, chemicals resistance and self lubrication,and low friction coefficient, easy to processing, suitable for using glass fiber and otherpacking filling enhance modification, and improve the performance and expand thescope of application.In-situ polymerization is a new method to prepare composite materials. It canmake the rigid chain inorganic particles and the matrix form in-situ at the same time,make nascent state of two kinds of material well mixed together, try to dispel theseparation of the tendency inorganic polymer particles and the buckling polymer, reachhigher level of scattered, and the process is simple, overcome the general moltenblending method, solution blending of the intrinsic defects of precipitation. It is one ofthe hot spot in the field of blend polymer materials in recent years that addingcarbon black in polymer preparation conductive polymer blend polymer materialsThis paper mainly includes two parts: study on preparation of PA6/carbon blackcomposites by the in-situ polymerization method and isothermal crystallizationkinetics of PA6/carbon black composites.1. Polyamide6/modified carbon black (PA6/MCB) composites were prepared byin situ polymerization method with carbon black particles as conductive particle, andpolyamide6as polymer matrix. DSC, FT-IR, SEM etc analytical method were used tocharacterizate Polyamide6/carbon black composites. The results show that, modifiedcarbon black (MCB) particles disperse well in PA6and have nuclear influence on PA6molecular chain. Compared with polyamide6, the crystallization temperature ofPA6/MCB offset high temperature direction. But with high carbon black fillingcontent, the crystallinity of PA6/MCB decline. The volume resistivity of PA6/MCBprepared by in situ polymerization method was higher than the composites’ preparedby molten blend duo to carbon black particles good dispersion in the matrix materials.2. In order to further investigate the crystallization and the crystal growth processof PA6/MCB, the non-isothermal crystallization kinetics of PA6/MCB was conductedin this chapter by DSC method. There are many theory and method of data processing about the non-isothermal crystallization kinetics on polymers. In this study, Jeziornyequation, Ozawa equation and Liu method were used to calculate. The result showsthat in the same cooling rate, the crystallization temperature of molten peak（Tmc）ofPA6/MCB was higher than that of PA6, half crystallization time（t1/2） of PA6thanthat of PA6/MCB, which proof MCB has good nuclear effect on PA6. At the start ofthe crystallization of PA6/MCB, Avrami index shows that the crystallization of PA6grow more complicated. Ozawa equation can describe the pure PA6crystallizationkinetics, but can’t describe PA6/MCB crystallization kinetics, mainly because thecrystallization process is obviously two crystallization. Kissinger and Friedman of thedifferential and conversion method to calculate activation energy of the two samplesof the crystallization, and the results show that both the crystallization of calculationby the trend of the activation energy is consistent, PA6are bigger than PA6/MCB,explain to join after the crystallization of PA6carbon that become easier.