Amine-Functionalized Poly(styrene) Microspheres as Thermoplastic Toughener for Epoxy Resin

作者：Chaudhary S; Surekha P; Kumar D; Rajagopal C; Roy P K^*

来源：Polymer Composites, 2015, 36(1): 174-183.

DOI：10.1002/pc.22927

In this article, the potential of amine-functionalized poly(styrene) (PS) microspheres as toughening agent for epoxy resin has been explored. PS microspheres were prepared by suspension polymerization, where the monomer concentration and stirring speed was varied to control the microsphere dimensions (52-183 mu m). The obtained microspheres were chemically functionalized with an aim to improve its dispersion within the epoxy matrix. The amine groups generated on the microsphere surface offer a potential site of covalent linkage with the epoxy matrix, thereby resulting in increased compatibility and improved properties. Epoxy composites containing varying amounts of microspheres (1-7% w/w) were prepared and their mechanical properties were evaluated under both quasi-static as well as dynamic conditions. The amination of poly(styrene) (APS) led to improved dispersion of the rigid microspheres in the epoxy matrix, which was evident from higher impact strength and fracture energies (G(IC)) as compared to its neat analogs. The izod impact strength and G(IC) increased by 33% and 150%, respectively, on introduction of 3% APS. This was accompanied with an increase in the tensile modulus and strength of the epoxy resin. Further increase in loading led to agglomeration of the microspheres, which in turn resulted in lowering of impact strength and toughness. Excellent agreement was found between the experimentally measured modulae and the predictions made on the basis of Halpin-Tsai and Lewis-Neilson models. Fracture surface morphology was studied to arrive at the principal toughening mechanisms behind the experimental findings. POLYM. COMPOS., 36:174-183, 2015.

• 出版日期2015-1