Fe3O4 particles were surface coated with a layer of polyvinyl acetate (PVAc), which could improve their compatibility with EVA composite hot melt adhesives and then further induce EVA segments to orientate.

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High performance cement slurry polymer modifiers are increasingly in demand in the cementing process of oil and gas. A new polymer modifier with outstanding fluid loss control and high strength and toughness was synthesized by the main monomers butyl acrylate (BA), methyl methacrylate (MMA), acrylamide (AM), the functional monomers vinyltriethoxysilane (VTS), glycidyl methacrylate (GMA) and the initiator of ammonium persulfate (APS) through emulsion polymerization. By using Fourier transform infrared (FTIR) spectrometer, a laser particle analyzer, a scanning electron microscope and a differential scanning calorimeter, we studied the mechanism of fluid loss control and microstructure of polymer latex cement slurries. The experimental results showed that the copolymer could be crosslinked at 160°C and have the lowest fluid loss control, 12 ml, when the polymer content reached 5%. Acrylate latex modified by the silane coupling agent VTS had excellent performance on fluid loss control, as well as mechanical properties for oil well cement. These results have a potential significant value for the development of a new polymer cement modifier with high thermal stability and durability.