改性马来酸酐橡胶接枝物增韧尼龙6的制备及表征

Preparation and characterization of modified maleic anhydride graft rubber toughened nylon 6

为了促进橡胶接枝物与尼龙6(PA6)的相容性并提高增韧效果,利用马来酸酐和对苯二胺合成了一种含酰胺键的二元羧酸,命名为对苯马来二酰胺二酸(改性马来酸酐,MDMA),并将MDMA接枝到三元乙丙橡胶(EPDM)上,制备出不同接枝率的改性马来酸酐橡胶接枝物(EPDM-g-MDMA),以EPDM-g-MDMA与PA6质量比为30∶70,通过共混挤出制备了含不同接枝率接枝物的EPDM-g-MDMA/PA6共混物。通过核磁共振和红外光谱对MDMA进行了测试,表明成功合成了所需要的二元羧酸。对共混物进行了相容性测试、DSC、熔融指数(MI)、SEM、拉伸和冲击力学性能测试。结果表明:随着接枝率的增大,共混物的熔融峰温度略有降低,其熔体黏度不断增大,橡胶接枝物在PA6基体中有良好的分散性,使EPDM-g-MDMA/PA6共混物的冲击强度提高了5.5倍,说明EPDM-g-MDMA对PA6的增韧效果较为明显。

In order to promote the compatibility between rubber graft and nylon 6 （PA6） and its toughening effect, the anhydride and p-phenylene diamine were used to compound a dicarboxylic acid containing an amide bond and named terephthalic diamide of maleic acid （modified maleic anhydride, MDMA）. MDMA was grafted onto ethylene propylene diene monomer（EPDM） to prepare modified maleic anhydride grafted rubbers（EPDM-g-MDMA）. EP- DM-g-MDMA/PA6 blends containing different graft ratio grafts were prepared when mass ratio of EPDM-g-MDMA to nylon6 （PA6） is 30 ： 70. MDMA was tested by NMR and FTIR for indicating the successful synthesis of the desired dicarboxylic acid. The results of compatibility test, DSC, melting index （MI） test, SEM, tensile and impact mechanical property tests of blends were preformed. Results show that with the graft ratio increasing, the melting peak temperature of the blend is slightly reduced, increasing the melt viscosity. The grafted rubber has good dispersion in PA6 matrix to make the impact strength of EPDM-g-MDMA/PA6 blends increased by 5.5 times, indicating EPDM-g-MDMA toughening PA6 effect is more obvious.