Research Of Polystyrene/Sepiolite Composite

As for Polymer/layered silicate composites shave excellent mechanical properties,heat-resistant and blocking performance, they gain widely popularity by material science.Using the characteristics of silicate clay to explore new and effective disperse methods,decentralized state and interfacial interaction effect on the composites’ properties of thesilicate clay is always the focus of such researches.In this study, polystyrene was matrix, PS/sepiolite composite materials were preparedwith two different forms of sepiolite as added materials. First usedHexadecyltrimethylammonium bromide (CTAB) through ion exchange method to intercalatethe surface of sepiolite, then used it with styrene monomer to polymerize by the in-situintercalated emulsion polymerization, and then intercalated the product and polystyrene withmelt intercalated, finally obtained PS/sepiolite composite materials.The microscopic structure and thermal, mechanical properties PS/sepiolitenanocomposites were tested, by means of X-ray diffraction (XRD), scanning electronmicroscopy(SEM), transmission electron microscopy (TEM), thermogravimetric analysis(TGA), mechanical property testing. XRD results showed that the lamellar spacing ofsepiolite increased obviously after many inserted layer, maximum reached2.81nm. Throughthe SEM, TEM photos found that in polystyrene/pure sepiolite composite materials, thesepiolite without surface treatment with its original morphology existed in polymer matrix,but the sepiolite after three times intercalated processing most evenly dispersed in polymermatrix, only a little appeared reunion phenomenon. Furthermore, images also indicated thatsepiolite reached the nanoscale at least in one direction, and had good interface combinationwith matrix. TGA analysis showed that PS/sepiolite composites compared with purepolystyrene, whose starting weightlessness temperature increased24℃, end thermogravimetictemperature increased16℃, and the biggest thermogravimetic temperature increased18℃.The mechanical performance tests showed that the impact strength of PS/sepiolite nanocomposites had greatly improved compared with pure polystyrene. Inpolystyrene/sepiolite (nap) composite materials, when modified4%, the impact strength ofcomposite materials achieved the maximum, in which2-1series were optimal. While, inPS/sepiolite (powder) composite materials, when additive amount of sepiolite was2%in1:2series, the impact strength of materials were best, and the impact strength increased37.7%than pure polystyrene.