Synthesis Of Norbornene Benzyl Amido Acid Salt Nucleating Agent And Study Of Nnucleating Property On Polypropylene

Nucleating agent can accelerate polypropylene crystallization rate and then improve the mechanical properties of polypropylene. Amide nucleating agent, as a new class (3-form nucleating agent, can improve toughness of iPP while decrease its stiffness. Carboxylate nucleating agent, as a new class a-form nucleating agent, can improve stiffness of iPP while decrease its toughness. Based on that amide and carboxylic acid salt are two kinds of good polypropylene nucleating agent, we mainly designed the norbornene benzyl amide salt nucleating agent and then studied the influence of it on crystallization process and mechanical properties. As far as I know, nucleating effect of this kind nucleating agent has not been reported.First of all, we got norbornene benzyl acid amide through the amidation reaction and eight kinds of norbornene benzyl amido acid salt by carbic anhydride and benzylamine, which were characterized by IR. The effect of nucleating agents on the mechanical, crystal and optical property of iPP were investigated. We found that norbornene benzyl amido acid monovalent salt including Li, Na and K, are good nucleating agent, which can make peak temperature of iPP increased by10℃and flexural modulus of iPP increased by ahout fifteen percent compared with pure iPP. Compared with pure iPP, flexural modulus of polypropylene nucleated by AM-11at the concentration of0.1wt%is increased by19%compared with pure iPP, from1314Mpa to1558Mpa. Among bivalent salt, only norbornene benzyl amido acid calcinm salt can make the flexural modulus of iPP increased by4.9%. Norbornene benzyl amido acid aluminum salt can make the flexural modulus of iPP decreased by13%。Concentration effect of AM-11was studied based on good property of it. The adding concentration is0、0.05、0.1、0.2、0.4、0.6、0.8wt%respectively. With the increase of AM-11concentration, crystallization peak temperature of polypropylene is increased first. Crystallization peak temperature nucleated by AM-11at the concentration of0.1wt%is increased from112.3℃to122.3℃. Crystallization peak temperature does not increase with concentration of AM-11above0.1wt%. With the increase of AM-11concentration, flexural modulus of polypropylene is increased first. Flexural modulus of iPP nucleated by AM-11at the concentration of0.1wt%is increased from930Mpa to1208Mpa. Flexural modulus does not increase with concentration of AM-11above0.1wt%. With the increase of AM-11 concentration, tensile strength of polypropylene is increased first. Tensile strength of iPP nucleated by AM-11at the concentration of0.1wt%is increased from29.33Mpa to31.97Mpa. Tensile strength does not increase with concentration of AM-11above0.1wt%. All in all,0.1wt%is the optimal concentration.Non-isothermal crystallization kinetics of iPP nucleated by AM-11was studied by means of Caze, and the Kissinger method was applied to calculate the crystallization activation energy. The results showed that the crystal growth mode was not changed by the adding of AM-11. With the increase of AM-11concentration, crystallization activation energy of polypropylene is increased first. Crystallization activation energy of iPP nucleated by AM-11at the concentration of0.05wt%is increased from239.5KJ/mol to290.5KJ/mol. Crystallization activation energy does not change much with concentration of AM-11above0.05wt%. Macromolecular chain movement is opposed because of interaction of nucleating agent and iPP. This conclusion is proved by increase of viscosity of iPP added nucleating agent.Finally, crystallization rate and final crystallization form of iPP nucleated by different concentration of AM-11was investigated. The spherulite size of nucleated iPP is dramatically decreased than that of pure iPP and its crystallization rate is accelerated compared with pure iPP by means of POM.