Preparation And Properties Of NBR/PA6 Thermoplastic Vulcanizates

This paper prepares nitrile rubber (NBR)/nylon 6 (PA6) thermoplastic elastomer (TPV) by dynamic vulcanization method, the study is about the effects of formulation and process of NBR/PA6 TPV on mechanical properties, morphology and rheological properties to prepare NBR/PA6 TPV with perfect morphology, excellent mechanical properties and outstanding manufacturing performance.HVA-2/DM and SP-1045/SnCl2 vulcanization systems are studied particularly, the changes of blends during different stages are discussed via the contrast of dynamic vulcanization characteristic curves, the instruction significance for twin-screw extrusion of the curves are illustrated, the influence of vulcanization agent content on NBR/PA6 TPV is also investigated.The effects of acrylonitrile content of NBR on NBR/PA6 TPV properties are examined. The influence of rubber/plastic mass ratio on mechanical properties, morphology and rheological properties are investigated respectively. There are several plasticizers to prepare NBR/PA6 TPV by dynamic vulcanization, especially high density Oxidized Polyethlene wax(AC-316A) and N-Butyl-benzenesulfonamide. Carboxylic butyl rubber with reactive carboxyl groups is adopted to compatibilize phase interface between rubber and plastic to improve the properties of NBR/PA6 TPV.The parameters of twin-screw extruder are studied, raising temperature accelerates vulcanization reactions and reduce shear force transmission efficiency because of the improvement of molten degree of continuous nylon phase, the increase of rotation speed improves shear force transmission efficiency, however, the retention time of the blends in the twin-screw extruder barrel reduces, which leads to vulcanization reacts and crush inadequately, thus there are proper technological parameters to prepare NBR/PA6 TPV with better properties.